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Billy Madison

July 27, 2018

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Helium

July 1, 2018

https://geology.com/articles/helium/

Where Does Helium Come From?

Very little helium is present in Earth’s atmosphere. It is such a light element that Earth’s gravity cannot hold it. When present at Earth’s surface, unconfined helium immediately begins rising until it escapes the planet. That’s why party balloons rise!

The helium that is produced commercially is obtained from the ground. Some natural gas fields have enough helium mingled with the gas that it can be extracted at an economical cost. A few fields in the United States contain over 7% helium by volume. Companies that drill for natural gas in these areas produce the natural gas, process it and remove the helium as a byproduct.

Why is Helium in Some Natural Gas?

Most of the helium that is removed from natural gas is thought to form from radioactive decay of uranium and thorium in granitoid rocks of Earth’s continental crust. As a very light gas, it is buoyant and seeks to move upward as soon as it forms. The richest helium accumulations are found where three conditions exist: 1) granitoid basement rocks are rich in uranium and thorium; 2) the basement rocks are fractured and faulted to provide escape paths for the helium; and, 3) porous sedimentary rocks above the basement faults are capped by an impermeable seal of halite or anhydrite. [1] When all three of these conditions are met, helium might accumulate in the porous sedimentary rock layer.

Helium has the smallest atomic radius of any element, about 0.2 nanometers. So, when it forms and starts moving upward, it can fit through very small pore spaces within the rocks. Halite and anhydrite are the only sedimentary rocks that can block the upward migration of helium atoms. Shales that have their pore spaces plugged with abundant organic materials (kerogen) sometimes serve as a less effective barrier.

helium-deposit-model

Helium-bearing natural gas deposits: Deposit model for helium-bearing natural gas fields in the United States. Helium is produced by the decay of uranium and thorium in granitoid basement rocks. The liberated helium is buoyant and moves toward the surface in porosity associated with basement faults. The helium then moves upward through porous sedimentary cover until it is trapped with natural gas under beds of anhydrite or salt. These are the only laterally-persistent rock types that are able to trap and contain the tiny, buoyant helium atoms. This geological situation only occurs at a few locations in the world and is why rich helium accumulations are rare.

Where is Natural Gas Rich in Helium?

Most unprocessed natural gas contains at least trace amounts of helium. Very few natural gas fields contain enough to justify a helium recovery process. A natural gas source must contain at least 0.3% helium to be considered as a potential helium source.

World Helium Resources
Country Billion Cubic Meters
United States 20.6
Qatar 10.1
Algeria 8.2
Russia 6.8
Canada 2.0
China 1.1
The values above are estimated helium resources from USGS Mineral Commodity Summaries. [3]

In 2010, all of the natural gas processed for helium in the United States came from fields in Colorado, Kansas, Oklahoma, Texas, Utah, and Wyoming as shown on the accompanying map. The Hugoton Field in Oklahoma, Kansas and Texas; the Panoma Field in Kansas; the Keyes Field in Oklahoma; the Panhandle West and Cliffside Fields in Texas, and the Riley Ridge Field in Wyoming account for most of the helium production in the United States. [2]

During 2010, the United States produced 128 million cubic meters of helium. Of that amount, 53 million cubic meters of helium were extracted from natural gas, and 75 million cubic meters were withdrawn from the National Helium Reserve. Other countries with known production amounts were: Algeria (18 mcm), Qatar (13 mcm), Russia (6 mcm), and Poland (3 mcm). Canada and China produced small but unreported amounts of helium. [3]

helium-map

Helium-bearing natural gas deposits: Map showing the natural gas fields that serve as important sources of helium in the United States. The natural gas produced from these fields contains between 0.3% to over 7% helium. The helium is removed from the gas for commercial sale. Image by Geology.com using location data from the United States Geological Survey. [2]

Vox: “Electric vehicles are gaining momentum, despite Trump”… Because S-curve!

June 28, 2018

Guest post by David Middleton

From the never-ending font of infotainment, David Roberts of Vox…

Electric vehicles are gaining momentum, despite Trump

Policymakers and analysts are digging into the details of how to get more EVs on the road.

By David Roberts Jun 28, 2018

The transportation sector today emits more carbon than any other sector of the US economy. And it is shaping up to be the next big battle in the long fight to decarbonize.

On one side of that battle: the Trump administration, a few US automakers, and Koch Industries, who would like to stymie or at least delay the electrification of vehicles and continue the use of fossil fuels.

On the other side: California, a coalition of like-minded states, most automakers, a growing roster of utilities, and climate hawks. All of them are eager to accelerate the shift to electric vehicles (EVs), so that the sector can be run on increasingly clean grid power.

Lately, the Trumpian side has had the upper hand. EPA Administrator Scott Pruitt has signaled that he wants to freeze fuel-economy standards at 2020 levels, while Koch-funded groups are fighting EV incentives and blocking public-transit projects around the country. And low oil prices have kept gas prices down, which means American consumers are once again opting for SUVs and trucks. Cars are practically disappearing from the market; Ford plans to stop selling almost all its cars by 2020.

bloomberg_suvs (1)

But underneath the surface, there is a frenzy of activity on the other side. It’s not just that states are pushing back and beginning to set their own stringent goals (like California’s, to put 5 million EVs on the street by 2030). It’s also that a broader coalition is taking on the real nuts and bolts of electrifying the US fleet, working out the details and best practices that will be necessary to put ambitious plans into motion.

[…]

Vox

Are EV’s gaining momentum?  Or does Mr. Roberts assume they are gaining momentum because the Peoples Republic of California is gaining momentum in setting goals?  Or, do futurists simply have difficulty conjugating verbs?

Mr. Roberts included a nice Bloomberg chart of SUV’s overtaking boring old cars in US sales.  If the article is about EV’s gaining momentum on the “front end of a steeply rising S-curve”… Why not plot a graph of EV’s gaining momentum relative to SUV’s… or at least gaining momentum relative to the cars that “are practically disappearing from the market”?  Well, the short answer is that EV’s fall about 190,000 monthly units below the bottom of the Bloomberg chart.

Mr. Roberts…

Mr. Data just can’t stop laughing at you.

However, Mr. Roberts does have a point: EV sales are what they are, despite Trump.

Regarding “gaining momentum”…

Definition of gather/gain momentum
: to move faster * The wagon gathered/gained momentum as it rolled down the hill.

Merriam-Webster

I don’t think so…

EVSales

Linear ≠ Gaining Momentum

Oh… Wait a second, Mr. Roberts also wrote this:

We are on the front end of a steeply rising S-curve, a rate of change not seen in the US transportation sector for decades. The temporary triumphs of the luddites in power should not obscure the fact that the work of making those forecasts real is beginning in earnest.

Are EV’s on the front end of an S-curve?  Or are they on the steeply rising bit of an S-curve?

An S-curve is a logistic function.  If EV sales are “gaining momentum,” they are somewhere between 10% and 50% of their ultimate market penetration.

Peak_EVs

An S-curve is a logistic function. The peak rate of growth occurs when half of the total is achieved. Peak Oil (AKA the Hubbert equation) is also a logistic function.

If EV sales are following an S-curve and are on the cusp of the “gaining momentum” bit, they have already achieved about 10% of their ultimate market penetration.  With a current market share of 1%, EV sales will max out at about 10% of US auto sales and peak EV sales growth will occur at about 5% market penetration.

Tony Stark Elon Musk and other futurists often claim that EV sales will follow an S-curve.  This leads to the question, “Do they know that an S-curve is a logistic function?”  I’m fairly certain that Tony Stark Elon Musk is aware of this… David Roberts of Vox, on the other hand…

 

 

So… Is the “S-curve” meme just a green propaganda tool to explain away the glacially slow pace of EV sales growth?   Or do the S-curve aficionados not understand what a logistic function is?

Here’s the really funny bit:  The longer EV sales plod along at a slow, linear rate of growth, the deeper the ultimate market share will be… if they are truly following an S-curve.

The Single Biggest Problem With the Younger Dryas Impact Hypothesis: Uniformitarian Impact Craters, Part Cinq

June 28, 2018

Guest commentary by David Middleton

  • YDIH = Younger Dryas Impact Hypothesis
  • YDB = Younger Dryas Boundary

Last month I shot a big hole in the latest YDIH paper.  This Science News article shoots another big hole in it.  The irony is that both of these particular holes were preexisting conditions: The contradictory data were either unknown to or ignored by the YDIH proponents.

Why won’t this debate about an ancient cold snap die?

Despite mainstream opposition, a controversial comet impact hypothesis persists

BY CAROLYN GRAMLING 2:00PM, JUNE 26, 2018

[…]

Geologists call this blip of frigid conditions the Younger Dryas, and its cause is a mystery. Most researchers suspect that a large pulse of freshwater from a melting ice sheet and glacial lakes flooded into the ocean, briefly interfering with Earth’s heat-transporting ocean currents. However, geologists have not yet found firm evidence of how and where this happened, such as traces of the path that this ancient flood traveled to reach the sea (SN: 12/29/12, p. 11).

But for more than a decade, one group of researchers has stirred up controversy by suggesting a cosmic cause for the sudden deep freeze. About 12,800 years ago, these researchers say, a comet — or perhaps its remnants — hit or exploded over the Laurentide Ice Sheet that once covered much of North America (SN: 6/2/07, p. 339).

[…]

The latest salvo came in March, when West and more than two dozen researchers published a pair of papers in the Journal of Geology. The papers include data from ice cores as well as sediment cores from land and sea. The cores contain signatures of giant wildfires that support the idea of a widespread burning event about 12,800 years ago, West says.

[…]

The March papers focus mainly on the wildfires, a long-standing aspect of the original hypothesis. Greenland ice cores show peaks in ammonium dating to the onset of the Younger Dryas, which the researchers say, suggests large-scale biomass burning. These data were previously presented in 2010 by astrophysicist Adrian Melott of the University of Kansas in Lawrence and colleagues. They suggested that the ammonium ions in those ice cores could be best explained by an extraterrestrial impact. A similar spike dating to 1908 — the year of the airburst over Siberia — had also been found in those same cores. The papers also describe finding peaks in charcoal that date to the start of the cold snap.

“The big thing here is a careful comparison of [many possible impact markers], normalized to the same dating method,” says Melott, one of the authors on the new impact papers. Those markers, including previously described evidence of microspherules, iridium and platinum dust, are consistent with having been caused by the same event, he says.

However, Jennifer Marlon, a paleoecologist and paleoclimatologist at Yale University and an expert on biomass burning, has taken her own look at sediments in North America dated to between 15,000 and 10,000 years ago. She sees no evidence for continent-wide fires dating specifically to the onset of the Younger Dryas.

“I’ve studied charcoal records for many years now,” Marlon says. In 2009, she and colleagues reported data on charcoal and pollen in lake sediments across North America. Importantly, the sediment records in her study encompassed not only the years of the Younger Dryas cold episode, but also a few thousand years before and after.

Her team found multiple small peaks of wildfires, but none of them were near the beginning of the Younger Dryas. “Forests burn in North America all the time,” she says. “You can’t find a cubic centimeter of sediment in any lake on this continent that doesn’t have charcoal in it.”

070718_cg_dryas_inline_6_graph_730

Missing peak: Charcoal records from 15 lake sediment cores from across North America show how often fires occurred at each site over 5,000 years. The records show no peak in burning about 12,800 years ago, as would be expected if there were continent-scale fires.

Such fires could be triggered by rapid climate change, when ecosystems are quickly reorganizing and more dead fuel might be available. “That can cause major vegetation changes and fires,” Marlon says. “We don’t need to invoke a comet.”

The problem with the data in the recent papers, Marlon says, is that the researchers look only at a narrow time period, making it difficult to evaluate how large or unusual the signals really were. From her data, there appeared to have been more burning toward the end of the Younger Dryas, when the planet began to warm abruptly again.

“That speaks to my fundamental problem with the biomass burning part of the papers,” Marlon says. “I don’t understand why they’re zooming in. It’s what makes me skeptical.”

Holliday echoes that criticism. “Most of the time they sample only around this time interval,” he says. What would be more convincing, he says, are data from cores that span 15,000 to 20,000 years, sampled every five centimeters or so. “If this is a unique event, then we shouldn’t see anything like it in the last 15,000 years.”

West says that other peaks are irrelevant, because the impact hypothesis doesn’t imply that there was only one wildfire, just that one occurred around 12,800 years ago. He adds that the new papers suggest that Marlon and her colleagues didn’t correctly calibrate the radiocarbon dates for their samples. When done correctly, he says, one spike in fires that Marlon estimated at around 13,200 years ago actually occurred several hundred years later — right around 12,800 years ago.

[…]

Science News

Why won’t the YDIH debate die?  Mostly because its fun and also because its proponents tunnel-vision on the YDB and ignore any observations that are inconsistent with the YDIH.

While the YDIH has a lot of problems, this is the biggest…

West says that other peaks are irrelevant, because the impact hypothesis doesn’t imply that there was only one wildfire, just that one occurred around 12,800 years ago. He adds that the new papers suggest that Marlon and her colleagues didn’t correctly calibrate the radiocarbon dates for their samples. When done correctly, he says, one spike in fires that Marlon estimated at around 13,200 years ago actually occurred several hundred years later — right around 12,800 years ago.

This is analogous to the biggest problem with AGW: There is no genuine anomaly to explain.

The Medieval Warm Period, Holocene Climatic Optimum and Eemian are said to be irrelevant because past warming not driven by CO2 has no relevance to recent warming which surely must be driven by CO2.  Recent warming is simply not anomalous.

 Temperature reconstruction (Ljungqvist, 2010), northern hemisphere instrumental temperature (HadCRUT4) and Law Dome CO2 (MacFarling Meure et al., 2006). Temperatures are 30-yr averages to reflect changing climatology.  The Good, the Bad and the Null Hypothesis.

Over the past 2,000 years, the average temperature of the Northern Hemisphere has exceeded natural variability (defined as two standard deviations (2σ) from the pre-1865 mean) three times: 1) the peak of the Medieval Warm Period 2) the nadir of the Little Ice Age and 3) since 1998.  Human activities clearly were not the cause of the first two deviations.  70% of the warming since the early 1600’s clearly falls within the range of natural variability.

While it is possible that the current warm period is about 0.2 °C warmer than the peak of the Medieval Warm Period, this could be due to the differing resolutions of the proxy reconstruction and instrumental data.

There is no wildfire anomaly associated with the YDB.  Even if you shift the dates, there’s no anomaly.  Because none of the peaks are anomalous.  An anomaly is a deviation from the norm.  If the norm is a fluctuation between wildfire frequencies of  0.0002 and 0.0003 peaks/site/year, a peak of 0.0003 peaks/site/year is not an anomaly, even it it was exactly at the YDB.  A YDB wildfire anomaly would significantly exceed (>2σ) the normal peak amplitude.

Note: The does not mean that it is incorrect to refer to HadCRUT4, GISTEMP, UAH or RSS as temperature anomalies.  The “norm” in these time series is an average temperature over a reference period.

A lot of the evidence for the YDIH has been very interesting.  Some of it has even been compelling.  However a lot of it has been poorly documented, unrepeatable, found to lack uniqueness and seriously unscientific (Carolina Bays… Argh).

 

No. The Miocene is not an example of the “last time it was as warm as it’s going to get later this century”… Argh!

June 19, 2018

Guest ridicule by David Middleton

From ARS Technica, one of the most incoherent things I’ve ever read…

WAIT, THERE IS HOPE! —

What happened last time it was as warm as it’s going to get later this century?

Kids today will be grandparents when most climate projections end—does the past have more hints?

HOWARD LEE – 6/18/2018

The year 2100 stands like a line of checkered flags at the climate change finish line, as if all our goals expire then. But like the warning etched on a car mirror: it’s closer than it appears. Kids born today will be grandparents when most climate projections end.

And yet, the climate won’t stop changing in 2100. Even if we succeed in limiting warming this century to 2ºC, we’ll have CO2 at around 500 parts per million. That’s a level not seen on this planet since the Middle Miocene, 16 million years ago, when our ancestors were apes. Temperatures then were about 5 to 8ºC warmer not 2º, and sea levels were some 40 meters (130 feet) or more higher, not the 1.5 feet (half a meter) anticipated at the end of this century by the 2013 IPCC report.

Why is there a yawning gap between end-century projections and what happened in Earth’s past? Are past climates telling us we’re missing something?

[…]

Can the Miocene tell our future?

The Mid-Miocene Climate Optimum (MMCO) was an ancient global warming episode when CO2 levels surged from less than 400ppm to around 500ppm.

[…]

ARS Technica

The shocking thing is that Howard Lee has a degree in geology.  The fact that he makes his living as an “Earth Science writer” and not as a geologist might just be relevant.

Can the Miocene tell our future?  I’ll let Bubba’s mom answer that question:

The fact that atmospheric CO2 levels may have surged from 400 to 500 ppm during the Middle Miocene Climatic Optimum is completely and totally fracking irrelevant in the Quaternary Period.

While the configuration of the continents was superficially similar to the modern world, there were substantial differences.

Middle Miocene paleogeography (Scotese, Paelomap)

Estimates of MMCO atmospheric CO2 levels range from less than 200 to about 500 ppm…

Neogene CO2

Neogene-Quaternary atmospheric CO2 levels.

Modern atmospheric CO2 levels are already within the MMCO range, but temperatures are MUCH, MUCH cooler than they were during the Miocene.

Neogene T

High Latitude SST (°C) From Benthic Foram δ18O (Zachos, et al., 2001) and HadSST3 ( Hadley Centre / UEA CRU via http://www.woodfortrees.org) plotted at same scale, tied at 1950 AD.

Oceanic and atmospheric circulation patterns were totally different in the Miocene.  Atmospheric CO2 levels are not the reason the Miocene was warmer than the Pliocene and Quaternary.

Tectonics and paleoclimate

The Miocene saw a change in global circulation patterns due to slight position changes of the continents and globally warmer climates. Conditions on each continent changed somewhat because of these positional changes, however it was an overall increase in aridity through mountain-building that favored the expansion of grasslands. Because the positions of continents in the Miocene world were similar to where they lie today, it is easiest to describe the plate movements and resulting changes in the paleoclimate by discussing individual continents.

In North America, the Sierra Nevada and Cascade Mountain ranges formed, causing a non-seasonal and drier mid-continent climate. The increasing occurrences of drought and an overall decrease in absolute rainfall promoted drier climates. Additionally, grasslands began to spread, and this led to an evolutionary radiation of open-habitat herbivores and carnivores. The first of the major periods of immigration via the Bering land connection between Siberia and Alaska occurred in the middle of the Miocene, and by the end of the Miocene the Panama isthmus had begun to form between Central and South America.

Plate tectonics also contributed to the rise of the Andes Mountains in South America, which led to the formation of a rain shadow effect in the southeastern part of the continent. The movement of the plates also facilitated trends favoring non-desert and highland environments.

In Australia, the climate saw an overall increase in aridity as the continent continued to drift northwards, though it went through many wet and dry periods. The number of rainforests began to decrease and were replaced by dry forests and woodlands. The vegetation began to shift from closed broad-leaved forests to more open, drier forests as well as grasslands and deserts.

Eurasia also experienced increasing aridification during the Miocene. Extensive steppe vegetation began to appear, and the grasses became abundant. In southern Asia, grasslands expanded, generating a greater diversity of habitats. However, southern Asia was not the only area to experience an increase in habitat variability. Southern Europe also saw an increase in grasslands, but maintained its moist forests. Although most of Eurasia experienced increasing aridity, some places did not. The climate in some Eurasian regions, such as Syria and Iran, remained wet and cool.

During the Miocene, Eurasia underwent some significant tectonic rearrangements. The Tethys Sea connection between the Mediterranean and Indian Ocean was severed in the mid-Miocene causing an increase in aridity in southern Europe (see next paragraph for more on this). The Paratethys barrier, which isolated western Europe from the exchange of flora and fauna, was periodically disrupted, allowing for the migration of animals. Additionally, faunal routes with Africa were well established and occasional land bridges were created.

Africa also encountered some tectonic movement, including rifting in East Africa and the union of the African-Arabian plate with Eurasia. Associated with this rifting, a major uplift in East Africa created a rain shadow effect between the wet Central-West Africa and dry East Africa. The union of the continents of Africa and Eurasia caused interruption and contraction of the Tethys Sea, thereby depleting the primary source of atmospheric moisture in that area. Thus rainfall was significantly reduced, as were the moderating effects of sea temperature on the neighboring land climates. However, this union enabled more vigorous exchanges of flora and fauna between Africa and Eurasia.

Antarctica became isolated from the other continents in the Miocene, leading to the formation of a circumpolar ocean circulation. Global ocean and atmospheric circulation were also affected by the formation of this circumpolar circulation pattern, as it restricted north-south circulation flows. This reduced the mixing of warm, tropical ocean water and cold, polar water causing the buildup of the Antarctic polar ice cap. This enhanced global cooling and accelerated the development of global seasonality and aridity.

UCMP Berkeley

Notice anything missing from the UCMP Berkeley discussion of the Miocene paleoclimate?

We’ve already experienced nearly 1 ºC of warming since pre-industrial time.  Another 0.5 to 1.0 ºC between now and the end of the century doesn’t even put us into Eemian climate territory, much less the Miocene.

Back to the ARS Technica nonsense…

130 feet of sea level rise

Between a third and three-quarters of Antarctic ice melted. Land liberated by retreating ice sprouted tundra and forests of beech and conifers, which can’t have happened unless Antarctic summers were warmer than 10ºC (50ºF—much warmer than the -5ºC/23ºF it is today). It’s not clear what Greenland was up to, but there may have been a small ice sheet in Northern Greenland that melted substantially.

Consequently, sea levels rose by a whopping 40 meters or so (~130 feet). To put that in perspective, Mid-Miocene-like sea levels today would draw a new US Atlantic coast roughly along Interstate 95 through Philadelphia, Baltimore, Richmond and Fayetteville, North Carolina, inundating the New York-New Jersey-Connecticut metro area, Boston, most of Florida, and the coastal Gulf of Mexico. Similar things would happen across densely populated lowland areas around the globe, home to a quarter of the world’s people.

Forty meters is just a bit more than the latest projections for modern sea level rise of 1-3 feet by 2100, and 4.5 to 5.25 feet (1.4-1.6 meters—home to about 5 percent of the world’s population) by 2300, assuming we stabilize warming to around 2ºC. The difference is, once again, partly explained by time. According to the 2017 US National Climate Assessment, 2ºC of warming would commit us to a loss of three-fifths of Greenland’s ice and one third of Antarctic ice, resulting in 25m (80ft) of sea level rise—but occurring over 10,000 years.

Even so, the Miocene hints that modern sea level rise could be larger and more rapid.

[…]

ARS Technica

2 ºC of warming would commit us to a loss of three-fifths of Greenland’s ice and one third of Antarctic ice, resulting in 25m (80ft) of sea level rise—but occurring over 10,000 years.

The East Antarctic ice sheet, 86% of Antarctica’s ice, hasn’t substantially melted in 8 million years.

Pages from pp1386a-2-web-23

Table 3 from USGS Professional Paper 1386-A-2.. 65 out of 80 potential meters of ice-related potential sea-level rise resides in the East Antarctic Ice Sheet. The Statue of Liberty has been saved!

You can’t get there from here!

Zachosetal2001_Cenozoic d18O_4

The East Antarctic Ice Sheet is stable below and probably a little above the dashed red line. Zachos temperature calculation on the right vertical axis is only for an ice-free ocean. The left vertical axis uses a conversion suitable for the Quaternary; however, the baseline is probably wrong.  SST’s shouldn’t be negative.  However, the relative change should be reasonably accurate.

The Greenland Ice Sheet didn’t even shrink by 3/5’s during the Eemian, when the Arctic was more than 5 ºC warmer than it is today.

The Greenland Ice Sheet only shrank by 1/3 relative to today during the much warmer Eemian interglacial.  X-axis is in calendar years AD(BC). A Geological Perspective of the Greenland Ice Sheet.

“Even so, the Miocene hints that modern sea level rise could be larger and more rapid.”

To paraphrase the judge in the Donny Berger case in That’s My Boy… “That  is just fracking mental.”  But she didn’t say “fracking.”

SL4_zps22bee1aa

Projected sea level rise through 2100 AD.

It really takes a special kind of stupid to base a wacked out climate catastrophe fantasy on the 400-500 ppm rise in atmospheric CO2 during of the Middle Miocene Climatic Optimum.

References

There’s a bunch of them.  I’ll get…

RoundTuit

Detailed references will be added when I get “a round tuit”… Get it? A round tuit!

The Mystery of Upheaval Dome: Uniformitarian Impact Craters, Part Quatre

May 30, 2018

Guest post by David Middleton

In my previous three posts on uniformitarian impact craters, we examined the pitfalls of drawing cartoons on Google Earth images without ever looking at the geology; how the Carolina Bays are as antithetical to impact features as any dents in the ground possibly could be; and poked a big hole in the latest Younger Dryas impact paper.

In part quatre (four for those who don’t pretend to speak French), we will look at Upheaval Dome in Canyonlands National Park, Utah… a supposedly confirmed impact crater.  In particular, we will examine how the world’s leading experts in impact craters and salt tectonics drew diametrically opposing conclusions from the same data.  This is another rather long post, with a lot of geology jargon.  I have included a glossary at the end of the post.

updome1

Figure 1. Aerial view of Upheaval Dome. Utah Geological Survey.

Upheaval Dome is a very enigmatic geological feature in Canyonlands National Park, Utah.  Since it was first described in 1927, several hypotheses have been put forward to explain its origin:

  • underlying salt dome
  • pinched-off salt diapir
  • cryptovolcanic explosion
  • fluid escape
  • meteoritic impact
  • and my personal favorite…

Over the years, all but two of these hypotheses have been shot down.

Pinched-off salt diapir or impact crater?

GEOSIGHTS: UTAH’S BELLY BUTTON, UPHEAVAL DOME

By William Case

Upheaval Dome in Canyonlands National Park, Utah, is a colorful circular “belly button,” unique among the broad mesas and deep canyons of the Colorado Plateau.

The rim of Upheaval Dome is 3 miles across and over 1000 feet above the core floor. The central peak in the core is 3000 feet in diameter and rises 750 feet from the floor.

Since the late 1990s, the origin of the Upheaval Dome structure has been considered to be either a pinched-off salt dome or a complex meteorite impact crater; in other words the “belly button” is either an “outie” (dome) or “innie” (crater).

Both origin hypotheses account for the overall structure of Upheaval Dome, assuming approximately a mile of overlying rock has been eroded. The main differences between the two hypotheses are the amount of time and the pressures needed to produce the structure.

A salt dome is produced when a subsurface layer of salt (originally deposited when a large body of saline water evaporated) is eventually squeezed upward because of the weight of overlying rock. At Upheaval Dome, the upward flow would have to have been “pinched off” by rock that fell into voids left by salt dissolved by surface water.

The pinched-off salt dome hypothesis assumes that up to 20 million years of moderate pressures produced the feature, compared to only a few minutes of extremely high to low pressure changes for the impact crater hypothesis.

Until recently, “smoking gun” evidence for either origin was absent because of erosion. No remnant pieces of salt or related rocks and minerals have been found to support the pinched-off salt dome hypothesis; neither were formerly molten rocks, ejected and crushed rock, or minerals altered by high pressure found to support the impact crater hypothesis.

Then, in 2007, German scientists Elmar Buchner and Thomas Kenkmann reported finding quartz crystals that were “shocked” by the high pressure of a meteorite impact. Many geologist now consider the mystery of Upheaval Dome’s origin to be solved (and it’s an “innie”!).

The core consists of the oldest rock formations at Upheaval Dome. The Organ Rock Shale and White Rim Sandstone of the Permian Cutler Group, and Triassic Moenkopi Formation were injected and pushed upward in a chaotic jumble. The Triassic Chinle Formation, Triassic-Jurassic Wingate Sandstone, and Jurassic Kayenta Formation and Navajo Sandstone are stacked, oldest to youngest, from the core to the rim.

[…]

Utah Geological Survey

Regional Setting

UHD_1

Figure 2. Schematic cross section of the Canyonlands National Park area.  The Paradox Salt Formation is the manila colored bulge underlying Canyonlands NP.  Upheaval Dome is out of the plane of the cross section, between Stillwater Canyon and Grandview Point. Capitol Reef Geological Cross Section, Capitol Reef Natural History Association.

UHD_2

Figure 3.  Canyonlands NP Stratigraphic Column.  Capitol Reef Natural History Association and Utah Geological Survey.

Canyonlands National Park and the entire Colorado Plateau are a “geologist’s paradise.”

From 2004-2007, we made several “field trips” to the region.  Upheaval Dome is almost dizzying.  These are some photos Mrs. Middleton (a fellow geo) took in 2007:

IMG_0159 140IMG_0150 131

IMG_0155 136

Figures 4, 5 & 6.  Photos of Upheaval Dome by Mrs. Middleton.

Can you believe that we forgot to include a lens cap for scale?

The light colored, greenish rock in the central part of the dome is the highly deformed Lower Triassic Moenkopi Formation.

UHD_3

Figure 7.  Upheaval Dome.  Utah Geological Survey.

Salt domes and impact craters are often surrounded by rim synclines.

Figure 8.  Examples of rim synclines. Cramez 2006.

Upheaval Dome has a rim syncline, surrounded by a rim monocline.  Salt domes often exhibit rim monoclines, impact craters don’t.

UHD_8

Figure 9.  Dome Encircling Monocline (DEM) = Rim Monocline or Ring Monocline.  Dome Encircling Syncline (DES) = Rim Syncline or Ring Syncline.  Geesaman 2015.

UHD_9

Figure 11.  Northern Paradox Basin Stratigraphic Column.  Geesaman 2015.

Upheaval Dome and Barringer Crater

The Colorado Plateau is also the host to one of the world’s most well-preserved and extensively studied impact features: Barringer Crater.  For a tremendous reference on Barringer Crater, I highly recommend David Kring’s Guidebook to the Geology of Barringer Meteorite Crater, Arizona (a.k.a. Meteor Crater).  

Barringer Crater is well-worth the price of admission.  While not as dizzying as Upheaval Dome, it is very impressive.

Meteor Crater_Arizona

Figure 12.  Barringer Crater (aka Meteor Crater), Arizona.  Photo by Mrs. Middleton.

Once again… We forgot to use a lens cap for scale… D’oh!

Barringer Crater is a “simple” impact crater.  If Upheaval Dome was an impact crater, it would be a “complex” crater.

simple-a-and-complex-b-crater-structure-credit-nasa

Figure 13.  Simple vs. complex impact craters. Brunetti 2014, original image from NASA.

About 145 million years of erosion has removed about 1 km of rock thickness from Upheaval Dome.  So the melt layers, impact breccia, ejecta fields and most other potential evidence for a meteoric impact are long-gone.  The highly deformed central uplift is assumed to be a remnant rebound feature of a complex crater.   On the other hand, the Barringer Crater impact occurred only 40-50 thousand years ago.  It is a nearly intact simple crater.

Here’s how the two geologic features compare:

Crater_map

Figure 14.  Geologic maps of Upheaval Dome and Barringer Crater plotted at the same scale.

Crater_xsect

Figure 15.  Cross sections of Upheaval Dome (Geesamen et al., 2015) and Barringer Crater (Roddy et al., 1975). Plotted at the same scale.

Honestly, at this point, I fail to see how anyone could interpret Upheaval Dome as an impact feature.

Shoemaker vs Jackson

Most readers of WUWT are familiar with the late Gene Schoemaker.

Gene Shoemaker – Founder of Astrogeology

April 28, 1928 – July 18, 1997

He once said he considered himself a scientific historian, one whose mission in life is to relate geologic and planetary events in a perspective manner. A modest statement coming from a legend of a man who almost single-handedly created planetary science as a discipline distinct from astronomy. He brought together geologic principles to the mapping of planets, resulting in more than 3 decades of discoveries about the planets and asteroids of the Solar System. He was a 1992 recipient of the National Medal of Science, the highest scientific honor bestowed by the President of the United States, then George Bush. His family, friends, former students, and the scientific community are in shock as they hear the news and feel the loss of “SuperGene.”

Dr. Gene Shoemaker died Friday, July 18, 1997 (Australian Time) in Alice Springs, Australia in a car accident. He was in the field, pursuing his lifelong passion of geologic studies to help understand impact craters with his wife and science partner, Carolyn Shoemaker. Carolyn survived the accident sustaining various injuries.

A longtime resident of Flagstaff, Arizona, in 1961 Gene invented the Branch of Astrogeology within the U.S. Geological Survey and established the Field Center in Flagstaff in 1963. Retired from the USGS in 1993, he has held an Emeritus position there and has been recently affiliated with Lowell Observatory in Flagstaff. An incredibly diverse person, he influenced science in numerous ways: most recently, in a decade-long sky survey for earth-crossing asteroids and comets, culminating in the discovery (with wife Carolyn and David Levy) of Comet Shoemaker-Levy, which impacted Jupiter in 1994, giving the world of science a major new insight into both the dynamics of comets and the planetary science of Jupiter. He has spent numerous summers (Australian winters) exploring ancient parts of the earth for records of meteorite and comet impacts, resulting in the discovery of a number of new craters. In much of his asteroid and comet work, Shoemaker collaborated closely with his wife, Carolyn, a planetary astronomer. A close and devoted couple, their work was recently featured in a 1997 National Geographic documentary “Asteroids: Deadly Impact.” They considered their work a “Mom and Pop” operation and together they initiated the Palomar Planet-crossing Asteroid Survey in 1973, and the Palomar Asteroid and Comet Survey in 1983.

Gene Shoemaker seems to have been a geologist from the day he was born in Los Angeles, California, in 1928. He did not even need to complete his higher education (B.S. and M.S., California Institute of Technology, 1947 and 1948; Ph.D. Princeton University after an interrupted career, 1960) before starting the practice of astrogeology that was to lead him to the planets. He began exploring for uranium deposits in Colorado and Utah in 1948, and these studies brought him geographically and intellectually near the many volcanic features and the one impact structure on the Colorado Plateau in the western United States, namely Hopi Buttes and Meteor Crater. In the period 1957-1960, he did his classic research on the structure and mechanics of meteorite impact. This work–including the discovery of coesite (a high pressure form of silica created during impacts) with E.C.T. Chao–provided the definitive work on basic impact cratering. It was work that he continued throughout his life–both by exploration of the earth–particularly in Australia–and the planets by remote sensing and mapping.

A man of vision, he believed geologic studies would be extended into space and in his early career he dreamed of being the first geologist to map the Moon. During the 1960’s he lead teams who were investigating the structure and history of the Moon and developing methods of planetary geologic mapping from telescope images of the Moon. A health problem prevented his being the first astronaut geologist, but he personally helped train the Apollo Astronauts and sat beside Walter Cronkite in the evening news giving geologic commentary during the Moon walks. He was involved in the Lunar Ranger and Surveyor programs, continued with the manned Apollo programs, and culminated his moon studies in 1994 with new data on the Moon from Project Clementine, for which he was the science-team leader.

Gene was the recipient of numerous awards including: Doctorate of Science Arizona State College, Flagstaff, 1965. Wetherill Medal of the Franklin Institute, co-recipient with E.C.T. Chao, 1965. Arthur S. Flemming Award, 1966. Doctorate of Science, Temple University, 1967. NASA Medal for Scientific Achievement, 1967. U.S. Department of the Interior Honor Award for Meritorious Service, 1973. Member, U.S. National Academy of Sciences, 1980. U.S. Department of the Interior Distinguished Service Award, 1980. Arthur L. Day Medal of the Geological Society of America, 1982. G.K. Gilbert Award of the Geological Society of America, 1983. Reiser Kulturpreis, co-recipient with E.C.T. Chao and Richard Dehm, 1983. Honorary Doctorate of Science, University of Arizona, 1984. Barringer Award of the Meteoritical Society, 1984. Kuiper Prize of the American Astronomical Society, Division for Planetary Sciences, 1984. Leonard Medal of the Meteoritical Society, 1985. Distinguished Alumni Award of the California Institute of Technology, 1986. Rittenhouse Medal of the Rittenhouse Astronomical Society, co-recipient with C.S. Shoemaker, 1988. U.S. National Medal of Science, 1992. Whipple Award, American Geophysical Union, 1993. Fellow, American Academy of Arts and Sciences, 1993. AIAA Space Science Award, 1996. NASA Exceptional Scientific Achievement Medal, 1996. Bowie Medal, American Geophysical Union, 1996. Special Award, American Association of Petroleum Geologists, 1997. Shoemaker Award, Texas Section of the American Institute of Professional Geologists, awarded posthumously, 1997.

From 1962 to 1985, Shoemaker blended his astrogeology research for the USGS with teaching at the California Institute of Technology (Caltech). He chaired Caltech’s Division of Geological and Planetary Sciences from 1969 to 1972. One of his doctorate students at Caltech, Dr. Susan Werner Kieffer, remembers him as being one of the most unfailingly generous, and intellectually honest mentors she has ever known. His colleagues at the USGS remember a exceptionally brilliant, exuberant, vibrant man and a warm human being whose angry antics over copy machines and loud happy laughter rang down the hallways. I remember a meeting when a newcomer to science overheard Gene’s excited conversation and laughter at a meeting and remarked “who is that loud guy?”–to which I replied that is the “god of planetary geology” and we all know that gods don’t whisper. As with his persona, Gene Shoemaker’s legacy will never be a whisper, but a loud burst onto the realm of Science that will be sorely missed. He is survived by his wife; his son, Patrick Shoemaker and wife Paula Kempchinsky; his daughters Christine Woodard and Linda Salazar and her husband Fred; and grandchildren, Sean and Adrian Woodard and Stefani Salazar, and a sister, Maxine Heath.

By Mary G. Chapman

USGS

On the other hand, I would guess that most WUWT readers and very few people outside the oil & gas industry are familiar with the work of the late Martin Jackson.

In Memoriam: Martin P. A. Jackson

June 1, 2016

Martin Jackson, world-renowned geoscientist and esteemed Bureau researcher, passed away early Tuesday, May 31.

Martin is recognized globally for his groundbreaking work in the field of salt tectonics, with over 100 papers and 3 books on the subject. Said Bureau colleague Michael Hudec in 2013: “He’s the number one person in the world by a goodly margin. His papers are universally regarded as the most authoritative on salt tectonics. And his name is associated with most of the major concepts in salt tectonics….You cannot work effectively in salt tectonics without reading Martin’s work.” In recent years, Jackson had been exploring signs of salt-tectonic activity on other planetary bodies, including Mars and Neptune’s moon Triton.

Born in Rhodesia (today, Zimbabwe), Jackson initially studied old, hard Precambrian gneisses before moving to Texas and eventually becoming immersed in, as he called it, “a subsurface world of very young, soft rocks.” He came to the Bureau in 1980 and in 1988 was instrumental in the creation of the Bureau’s first Industrial Associates program, the Applied Geodynamics Laboratory (AGL), founded to investigate the then-poorly-understood world of salt tectonics. With seed money from UT Austin and the member support of 13 oil and gas companies, Jackson’s new consortium became a model for those to follow. Over 25 years after its founding, the AGL now maintains over 30 participating companies and is widely considered the world’s preeminent salt-tectonics research laboratory. Today, it is almost impossible to talk about salt tectonics without using terms and concepts developed at the AGL, including salt canopy, salt weld, reactive diapir, squeezed diapir, extrusive salt sheet, and multidirectional extension.

Jackson’s numerous major career honors include the American Association of Petroleum Geologists’ Robert R. Berg Outstanding Research Award (2010) in recognition of outstanding innovation in petroleum geoscience research and the Geological Society of London’s William Smith Medal (2013) for outstanding research in applied geology. According to AAPG records, no one has won more AAPG technical awards, nor has anyone won in as many technical categories. Jackson’s notable publications include the AAPG Memoir Salt Tectonics: A Global Perspective (2008, with David Roberts and Sig Snelson), a definitive book on the subject, and the major 2012 atlas The Salt Mine (with Bureau colleague Hudec), an interactive resource on salt tectonics. Jackson’s publication legacy will continue as co-author (also with Hudec) of the forthcoming Salt Tectonics: Principles and Practice, to be published in September 2016 by Cambridge University Press.

In addition to his preeminence as a research scientist, Martin Jackson is equally regarded for his strength of character, gracious demeanor, and unfailing humor. His friends and peers recall his kindness, humility, insightfulness, and remarkable equanimity.

Bureau director Scott W. Tinker said, in conveying the loss of his friend to the Bureau family, that “Martin was one of the finest people I have known. Practical. Brilliant. Creative. Dedicated to his family and his science until the end. He will be missed but always remembered.”

Bureau of Economic Geology, The University of Texas at Austin

Gene Shoemaker and Martin Jackson were brilliant geologists and the leading scientists, if not founders, of their respective disciplines.  Both have written extensively on the subject of Upheaval Dome, they have built upon each other’s work and that of other geoscientists… And they couldn’t have disagreed any more profoundly.  Both of these brilliant geologists, employing the archaic principles of uniformitarianism, came to very firm and diametrically opposing conclusions.  Maybe… If they had just drawn cartoons on Google Earth images… Sorry, couldn’t resist…

Here is a sampling of the back-and-forth:

Jackson 1998…

Structure and evolution of Upheaval Dome: A pinched-off salt diapir

Abstract

Upheaval Dome (Canyonlands National Park, Utah) is an enigmatic structure previously attributed to underlying salt doming, cryptovolcanic explosion, fluid escape, or meteoritic impact. We propose that an overhanging diapir of partly extrusive salt was pinched off from its stem and subsequently eroded. Many features support this inference, especially synsedimentary structures that indicate Jurassic growth of the dome over at least 20 m.y. Conversely, evidence favoring other hypotheses seems sparse and equivocal.

In the rim syncline, strata were thinned by circumferentially striking, low-angle extensional faults verging both inward (toward the center of the dome) and outward. Near the dome’s core, radial shortening produced constrictional bulk strain, forming an inward-verging thrust duplex and tight to isoclinal, circumferentially trending folds. Farther inward, circumferential shortening predominated: Radially trending growth folds and imbricate thrusts pass inward into steep clastic dikes in the dome’s core.

We infer that abortive salt glaciers spread from a passive salt stock during Late Triassic and Early Jurassic time. During Middle Jurassic time, the allochthonous salt spread into a pancake-shaped glacier inferred to be 3 km in diameter. Diapiric pinch-off may have involved inward gravitational collapse of the country rocks, which intensely constricted the center of the dome. Sediments in the axial shear zone beneath the glacier steepened to near vertical. The central uplift is inferred to be the toe of the convergent gravity spreading system.

Jackson et al., 1998

Shoemaker 1999…

Geology of the Upheaval Dome impact structure, southeast Utah

Abstract. Two vastly different phenomena, impact and salt diapirism, have been proposed for the origin of Upheaval Dome, a spectacular scenic feature in southeast Utah. Detailed geologic mapping and seismic refraction data indicate that the dome originated by collapse of a transient cavity formed by impact. Evidence is as follows: ( 1) sedimentary strata in the center of the structure are pervasively imbricated by top-toward-the-center thrust faulting and are complexly folded as well; (2) top-toward-the-center normal faults are found at the perimeter of the structure; (3 ) clastic dikesa re widespread; (4 ) the top of the underlying salt horizon is at least 500 m below the surface at the center of the dome, and there are no exposures of salt or associated rocks of the Paradox Formation in the dome to support the possibility that a salt diapir has ascended through it; and (5) planar microstructures in quartz grains, fantailed fracture surfaces (shatter surfaces), an rare shatter cones are present near the center of the structure. We show that the dome formed mainly by centerward motion of rock units along listric faults. Outcrop-scale folding and upturning of beds, especially common in the center, are largely a consequence of this motion. We have also detected some centerward motion of  fault-bounded wedges resulting from displacements on subhorizontal faults that conjoin and die out within horizontal bedding near the perimeter of the structure.  The observed deformation corresponds to the central uplift and the encircling ring structural depression seen in complex impact craters.

[…]

The presence of known salt structures in the region influenced early interpretations that Upheaval Dome resulted from salt diapirism, but it is noteworthy that there are no other similar-size domal structures visible elsewhere in this part of the Colorado Plateau.

[…]

Kriens, Shoemaker and Herkenoff, 1999

Nothing described in Kriens et al., 1999 is inconsistent with a pinched-off salt diapir.  I’ve worked salt basins since 1981 (East Texas and the Gulf of Mexico) and I’ve seen plenty of salt structures that didn’t look like any other salt structures in their respective basins.

Naturally, being an oil industry geoscientist, who has spent his entire career working salt basins and learned most of what I know about salt tectonics from the works of Martin Jackson and interpreting seismic data in East Texas and the Gulf of Mexico, I am clearly biased in favor of Martin Jackson’s interpretation.  Petroleum geologists have been predisposed to various salt diapir hypotheses for a very long time.

I am fortunate enough to have an original 1972 copy of this book (along with a mimiograph copy of the errata).

×20180525_050204

Figure 17.  ‘RMAG’s Geologic Atlas of the Rocky Mountain Region was an instant classic when published in 1972 on the occasion of RMAG’s 50th Anniversary. Affectionately known as the “Big Red Book,” its extensive paleogeographic maps remain a valuable resource to this day. The Atlas was the product of six years labor with an editorial staff of 26 and authors hailing from 43 separate companies and institutions.” http://store.aapg.org/detail.aspx?id=1169

20180525_045658

Figure 18.  “The structure is a collapsed salt dome in the Paradox basin.”

Uhm… yeah.

Upheaval Dome *should* appear different than any other salt structure in the Paradox Basin:

Paradox_Top_of_Salt

Figure 19.  Structure map of top of Paradox Salt Formation. Contour interval = 1,000′. Utah Geological Survey.

The most prominent salt structures in the Paradox Basin are the elongate “salt walls” in the northeastern part of the basin.  These NW-SE striking features are up to 100 miles long, with 6,000′ of vertical relief.  The salt is subaerially exposed in several locations along the crests of the salt walls.

Upheaval Dome is in the southwestern part of the basin.  It is in an area where the salt structures are primarily low-relief salt-cored anticlines (bumps), many of which are elongated.  Upheaval Dome has much higher vertical relief (>2,000′) than any nearby salt anticline and is nearly circular.

It’s obvious from this gravity map that Upheaval Dome is unlike any other salt structure in the Paradox Basin:

Paradox_Gravity_Map

Figure 20.  Paradox Basin gavity gradient map. Geesaman 2015. Upheaval Dome sticks out like a sore thumb.

In 2000 NASA sponsored a seismic reflection and refraction survey in an effort to image the subsurface structure (Kanbur et al., 2000).  They concluded that there was no evidence of a salt diapir beneath Upheaval Dome, despite the fact that their seismic profiles didn’t cover the dome itself.  They only covered the rim monocline and rim syncline.  The seismic profiles were consistent with both hypotheses.  However, it did indicate the presence of salt beneath the rim syncline; which is unusual, but not unprecedented, for a pinched-off salt diapir.

In 2001, Martin Jackson published a book on Upheaval Dome that addressed the conclusions of Krien’s et al., 1999 (Shoemaker), particularly the crushed quartz grains and clastic dikes:

Structure and Evolution of Upheaval Dome: Pinched-Off Salt Diapir or Meteoritic Impact Structure?

Abstract

Upheaval Dome (Canyonlands National Park, Utah) is an enigmatic structure previously attributed to underlying salt doming, cryptovolcanic explosion, fluid escape, or meteoritic impact. We instead propose that an overhanging diapir of partly extrusive salt was pinched off from its stem and subsequently eroded. Many features support this inference, especially synsedimentary structures that indicate Jurassic growth of the dome over at least 20 m.y. Conversely, evidence favoring other hypotheses is sparse and equivocal.

[…]

Crushed Quartz Grains

Quartz grains that have been crushed or shattered into pieces in the clastic dikes were used as evidence of impact by Shoemaker and Herkenhoff (1984), and although we found microfractured quartz in the dikes (fig. 40), even widespread microfractured quartz is geologically common. For example, quartz grains are crushed and mechanically rearranged by compaction during burial (Milliken, 1994; Dickinson and Milliken, 1995); they are common in fault zones within 100 m of even small-displacement (~100 m) fault surfaces (Anders and Wiltschko, 1994).  Microfractures are typically masked by recementation of authigenic quartz between and in optical continuity with the shards. Electron-beam-induced cathodoluminescence of our Upheaval Dome sample reveals that the quartz undulatory extinction is caused by slightly misoriented grain fragments separated by microfractures sealed by cement (fig. 40a). Brittle deformation and sealing of this type is common in faulted rocks (Anders and Wiltschko, 1994).

Jackson et al., 2001 pg 55

The downloadable PDF is available from the Texas Bureau of Economic Geology for $15.

Jackson compiled a table of the evidence for and against both an impact feature and a pinched-off salt diapir.

Table 1 from Jackson et al., 2001…

Incompat. with impact Compat. with pinch-off Compat. with impact Incompat. with pinch-off
POSITIVE EVIDENCE
Circularity X X
Central uplift X X
Clastic dikes X X
Crushed quartz grains X X
Inner constrictional zone X X
Outer extensional zone X X
Radial flaps (dog tongues) X X
Presence of underlying salt X X
Gravity and magnetic anomalies X X
Contiguous anticline X X
Nearby salt structures X X
Rim syncline X X
Rim monocline X X
Growth folds X X
Growth faults X X
Shifting rim synclines X X
Truncations and channeling X X
Onlap X X
Multiple fracturing and cementation X X
Steep zones X X
Outward-verging  extension X X
Volume imbalance X X
Shatter cones X X
Salt below rim syncline X X
NEGATIVE EVIDENCE
Absence of salt at the surface X X
Paucity of nearby piercement diapirs X X
Absence of meteoritic material X X
Absence of melt X X
Absence of in-situ breccia X X
Absence of shock-metamorphic minerals X X
Paucity of planar microstructures in quartz X X
Absence of ejecta breccia X X
Absence of outer fault terracing X X
Absence of overturned peripheral flap X X

The evidence overwhelmingly supported the salt diapir hypothesis.  Although it clearly did not rule out an impact feature, as most of the positive evidence was consistent with both hypotheses.

At this point, the score was:

  • Pinched off salt diapir 30
  • Impact crater -2

Then along came a “smoking gun”

Upheaval Dome, Utah, USA: Impact origin confirmed

Abstract

Upheaval Dome is a unique circular structure on the Colorado Plateau in SE Utah, the origin of which has been controversially discussed for decades. It has been interpreted as a crypto volcanic feature, a salt diapir, a pinched-off salt diapir, and an eroded impact crater.  While recent structural mapping, modeling, and analyses of deformation mechanisms strongly support an impact origin, ultimate proof, namely the documentation of unambiguous shock features, has yet to be successfully provided. In this study, we document, for the first time, shocked quartz grains from this crater in sandstones of the Jurassic Kayenta Formation. The investigated grains contain multiple sets of decorated planar deformation features. Transmission electron microscopy (TEM) reveals that the amorphous lamellae are annealed and exhibit dense tangles of dislocations as well as trails of fluid inclusions. The shocked quartz grains were found in the periphery of the central uplift in the northeastern sector of the crater, which most likely represents the cross range crater sector.

Buchner & Kenkmann, 2008

This bit is laughable:

While recent structural mapping, modeling, and analyses of deformation mechanisms strongly support an impact origin…

Prior to the discovery of 2 shocked quartz grains in the Jurassic Kayenta Formation, there was no unambiguous evidence that Upheaval Dome was an impact feature.  However, the detection of planar deformation features (PDF’s) did provide clear evidence for a meteoric impact.

Final Score

  • Pinched off salt diapir 28
  • Impact crater 0

Unless… the PDF’s were examples of tectonic deformation lamellae in quartz.  Or the 2 shocked quartz grains were detrital… as are most quartz grains in sandstone.

However, the PDF’s do appear to be evidence of an impact event… somewhere in or around the Paradox Basin at some point during or earlier to the deposition of the Kayenta Formation.

End of story… Right?  Wrong.

Nothing is over until we say it’s over!

New Evidence for Long-Term, Salt Related Deformation at Upheaval Dome, SE Utah*

Patrick J. Geesaman 1, Bruce D. Trudgill 2, Thomas E. Hearon IV 3, and Mark G. Rowan 4

Search and Discovery Article #10756 (2015)**  Posted August 3, 2015  *Adapted from oral presentation given at AAPG Annual Convention & Exhibition, Denver, Colorado, May 31-June 3, 2015
**Datapages © 2015 Serial rights given by author. For all other rights contact author directly.
1 Anadarko Petroleum Corporation, Houston, TX, USA
2 Geology & GE, Colorado School of Mines, Golden, CO, USA (btrudgil@mines.edu)
3 Structure and Geomechanics, Geological Technology, ConocoPhillips Company, Houston, TX, USA
4 Rowan Consulting, Inc., Boulder, CO, USA

Abstract

Upheaval Dome is an eroded structural dome that exposes Mesozoic strata along with associated folds, faults and sand injectites in the Paradox basin, SE Utah. Multiple interpretations for its origin have been proposed, but the two remaining viable hypotheses are at opposite ends of the geologic spectrum: one proposing long-term salt-related deformation and growth of the structure, the other a catastrophic meteorite impact.  Analysis of stratigraphic field data collected in Triassic to Jurassic-aged strata adjacent to Upheaval Dome reveals: (1) stratigraphic thicknesses from measured sections for the Kayenta Formation (~199 to ~195 Ma) that range from 7 meters to 224 meters, and projected thicknesses in cross section that can exceed 400 meters; (2) distinct changes in facies distributions in relation to mapped structures; (3) localized angular unconformities and stratal-onlap surfaces; (4) blocks of Triassic Chinle Formation encased in younger Jurassic Wingate Sandstone adjacent to thinned, Wingate lobes, that apparently downlap onto the underlying Chinle. Structural analysis at Upheaval Dome reveals: (1) synclinal growth axes and associated depositional centers shift away from the center of the dome throughout the Late Triassic/Early Jurassic; (2) stratigraphic thicknesses increase across normal faults on the scale of meters to tens of meters; (3) thrust faults within the Kayenta Formation verge to the southeast regardless of location around the structure. These structural features and associated growth strata offer compelling evidence for long-term deformation compatible with salt tectonics at Upheaval Dome during the Late Triassic/Early Jurassic. Sparse indicators of catastrophic impact are present in the Kayenta Formation in the form of two shocked quartz grains, orders of magnitude less than would be expected <1 km from a meteorite impact site. We interpret these grains to be detrital and sourced from outside the Paradox basin. In our interpretation of salt-related deformation, we discuss the merits and drawbacks of a model invoking collapse over a buried salt high to a prior model of a pinched-off diapiric feeder to an eroded salt glacier. The possibility that a meteorite impact of Late Permian to Early Triassic age initiated the growth of an isolated salt pillow in the western part of the northern Paradox Basin requires further investigation.

AAPG Search and Discovery

Instead of a post-Jurassic impact event (~ 2 minutes) vs. slow, steady growth of a subsequently pinched-off salt diapir from the Late Triassic through at least the Early Jurassic (~20 million years)… Geesamen et al., 2015 put forward the hypothesis that an impact occurred much earlier, during the Early Triassic followed by the initiation of salt movement and the slow growth of a salt dome from the Early Triassic (~250-240 Ma) through at least the Early Jurassic (~195-170 Ma), a period of 45 to 80 million years.  This actually better explains the presence of at least 2 shocked quartz grains in the Early Jurassic Kayenta Formation than a post-Jurassic impact does.  It also explains the clear stratigraphic evidence for slow structural growth over millions of years.

There you have it, a hypothesis that accommodates all of the unambiguous evidence.

  • Unambiguous evidence for an impact: 2 shocked quartz grains in the Early Jurassic.
  • Unambiguous evidence for a salt diapir: Structural growth from the Late Triassic through Early Jurassic.

We have both kinds…

We have both kinds of evidence: Salt diapirism and meteoric impact.

QED

Figure 21. Evidence of syndepostional structural growth around Upheaval Dome is unambiguous evidence that the structure was formed over a period of at least 45-70 million years. Geesamen et al., 2015.

I’m sure someone is asking, “How could it be possible that two of the foremost geologists in the world could look at the same data and come away with diametrically opposing interpretations?  Furthermore, how could a geologist barely out of grad school come along and demonstrate that they were both wrong?”  

Even if no one is asking this question, or questions, I’ll answer it with a poem (and I hate poetry almost as much as I hate folk music):

Bally_Seis_Strat

Figure 22.  Geology & geophysics are often analogous to a group of blind men interpreting an elephant.  AAPG.

Since the image is probably too small to read, here’s the poem…

It was six men of Indostan,
To learning much inclined,
Who went to see the Elephant
(Though all of them were blind),
That each by observation
Might satisfy his mind.

The First approach’d the Elephant,
And happening to fall
Against his broad and sturdy side,
At once began to bawl:
“God bless me! but the Elephant
Is very like a wall!”

The Second, feeling of the tusk,
Cried, -“Ho! what have we here
So very round and smooth and sharp?
To me ’tis mighty clear,
This wonder of an Elephant
Is very like a spear!”

The Third approach’d the animal,
And happening to take
The squirming trunk within his hands,
Thus boldly up and spake:
“I see,” -quoth he- “the Elephant
Is very like a snake!”

The Fourth reached out an eager hand,
And felt about the knee:
“What most this wondrous beast is like
Is mighty plain,” -quoth he,-
“‘Tis clear enough the Elephant
Is very like a tree!”

The Fifth, who chanced to touch the ear,
Said- “E’en the blindest man
Can tell what this resembles most;
Deny the fact who can,
This marvel of an Elephant
Is very like a fan!”

The Sixth no sooner had begun
About the beast to grope,
Then, seizing on the swinging tail
That fell within his scope,
“I see,” -quoth he,- “the Elephant
Is very like a rope!”
And so these men of Indostan
Disputed loud and long,
Each in his own opinion
Exceeding stiff and strong,
Though each was partly in the right,
And all were in the wrong!

MORAL,

So, oft in theologic wars
The disputants, I ween,
Rail on in utter ignorance
Of what each other mean;
And prate about an Elephant
Not one of them has seen!

Blind Men and the Elephant – A Poem by John Godfrey Saxe via All About Philosophy

That said… It’s a salt diapir… Sorry.

Applications to climate science

The “Blind Men and the Elephant” is even more applicable to climate science than it is to geology & geophysics.  The difference is that most climate scientists don’t seem to realize this.

Did you ever notice how government and closely affiliated academic scientists seem to interpret data with the intent of finding a specific answer, while private sector and closely affiliated academic scientists interpret data with the intent of finding the answer that best explains all of the observations?  I notice this all the time.  In the case of Upheaval Dome, it seems that NASA-affiliated scientists were hell-bent on it being an impact feature.  So hell-bent as to basically ignore almost all of the evidence.  This strikes me as being very similar to the way government and closely affiliated academic climate scientists tend to view things this way:

slide12

JC at the National Press Club, Climate Etc.

Glossary

Anticline

1. n. [Geology]
An arch-shaped fold in rock in which rock layers are upwardly convex. The oldest rock layers form the core of the fold, and outward from the core progressively younger rocks occur. Anticlines form many excellent hydrocarbon traps, particularly in folds with reservoir-quality rocks in their core and impermeable seals in the outer layers of the fold. A syncline is the opposite type of fold, having downwardly convex layers with young rocks in the core.

Breccia

Breccia is a term most often used for clastic sedimentary rocks that are composed of large angular fragments (over two millimeters in diameter). The spaces between the large angular fragments are filled with a matrix of smaller particles and a mineral cement that binds the rock together.

Clastic

1. n. [Geology]
Sediment consisting of broken fragments derived from preexisting rocks and transported elsewhere and redeposited before forming another rock. Examples of common clastic sedimentary rocks include siliciclastic rocks such as conglomerate, sandstone, siltstone and shale. Carbonate rocks can also be broken and reworked to form clastic sedimentary rocks.

Clastic dike

A tabular body of clastic material transecting the bedding of a sedimentary formation, representing extraneous material that has invaded the containing formation along a crack, either from below or from above.

Detrital

1. adj. [Geology]
Pertaining to particles of rock derived from the mechanical breakdown of preexisting rocks by weathering and erosion. Detrital fragments can be transported to recombine and, through the process of lithification, become sedimentary rocks. Detrital is usually used synonymously with clastic, although a few authors differentiate between weathering of particles, which forms detrital sediments, and mechanical breakage, which produces clastic sediments.

Diapir

1. n. [Geology]
A relatively mobile mass that intrudes into preexisting rocks. Diapirs commonly intrude vertically through more dense rocks because of buoyancy forces associated with relatively low-density rock types, such as salt, shale and hot magma, which form diapirs. The process is known as diapirism. By pushing upward and piercing overlying rock layers, diapirs can form anticlines, salt domes and other structures capable of trapping hydrocarbons. Igneous intrusions are typically too hot to allow the preservation of preexisting hydrocarbons.

OGL98055-t

Listric fault

1. n. [Geology]
A normal fault that flattens with depth and typically found in extensional regimes. This flattening manifests itself as a curving, concave-up fault plane whose dip decreases with depth.

Monocline

(geology) A unidirectional dip in strata that is not a part of an anticline or syncline
(geology) A single flexure in otherwise flat-lying strata

Planar deformation features

Planar deformation features, or PDFs, are optically recognizable microscopic features in grains of silicate minerals (usually quartz or feldspar), consisting of very narrow planes of glassy material arranged in parallel sets that have distinct orientations with respect to the grain’s crystal structure.

PDFs are only* produced by extreme shock compressions on the scale of meteor impacts. They are not found in volcanic environments. Their presence therefore is a primary criterion for recognizing that an impact event has occurred.

* Except when PDF’s are produced by tectonic forces.

Rim syncline

A syncline partially surrounding a salt dome. It results from withdrawal of salt that has moved into the dome.

Syncline

1. n. [Geology]
Basin- or trough-shaped fold in rock in which rock layers are downwardly convex. The youngest rock layers form the core of the fold and outward from the core progressively older rocks occur. Synclines typically do not trap hydrocarbons because fluids tend to leak up the limbs of the fold. An anticline is the opposite type of fold, having upwardly-convex layers with old rocks in the core.

Syndepositional

(geology) Occurring at the same time as deposition

References

Billingsly, George H. and William J. Breed.  “Capitol Reef Geological Cross Section.” Published by the Capitol Reef Natural History Association, Torrey Utah 84775 ©1980 Capitol Reef Natural History Association. Reprinted 1996 Lithography by Lorraine Press Salt Lake City, Utah

Blenkinsop T. G. and Drury M. R. D. 1988. Stress estimates and fault history from quartz microstructures. Journal of Structural Geology 10:673–684.

Brunetti, Maria. (2014). “Statistics of terrestrial and extraterrestrial landslides.” PhD Thesis. 10.13140/2.1.4107.3444.

Buchner, Elmar & Kenkmann, Thomas. (2008). “Upheaval Dome, Utah, USA: Impact origin confirmed.” Geology. 36. 227-230. 10.1130/G24287A.1.

Cramez, Carlos. Glossary of Salt Tectonics.” (2006).  Universidade Fernando Pessoa. Porto, Portugal.

Geesaman, J., Patrick & Trudgill, Bruce & Hearon, Thomas & Rowan, Mark. (2015). “New Evidence for Long-Term, Salt-Related Deformation at Upheaval Dome, SE Utah.”  2015 AAPG Annual Convention and Exhibition, At Denver Colorado.

Hamers, Maartje & Drury, M.R.. (2011). “Scanning electron microscope‐cathodoluminescence (SEM‐CL) imaging of planar deformation features and tectonic deformation lamellae in quartz.” Meteoritics & Planetary Science. 46. 1814 – 1831. 10.1111/j.1945-5100.2011.01295.x.

Jackson, Martin & Schultz-Ela, Dan & Hudec, Michael & Watson, IA & L. Porter, M. (1998). “Structure and evolution of Upheaval Dome: A pinched-off salt diapir.” Geological Society of America Bulletin – GEOL SOC AMER BULL. 110. 1547-1573. 10.1130/0016-7606(1998)110<1547:SAEOUD>2.3.CO;2.

Jackson, M.P.A., D. D. Schultz-Ela, M. R. Hudec, I. A. Watson, and M. L. Porter.  RI0262. “Structure and Evolution of Upheaval Dome: Pinched-Off Salt Diapir or Meteoritic Impact Structure?”  Bureau of Economic Geology, The University of Texas at Austin. 2001.

Kanbur, Z., J. N. Louie, S. Chávez‐Pérez, G. Plank, and D. Morey (2000), Seismic reflection study of Upheaval Dome, Canyonlands National Park, Utah. J. Geophys. Res.105(E4), 9489–9505, doi:10.1029/1999JE001131.

Kriens, Bryan & M. Shoemaker, Eugene & Herkenhoff, K. (1999). “Geology of the Upheaval Dome impact structure, southeast Utah.” Journal of Geophysical Research. 104. 18867-18888. 10.1029/1998JE000587.

Kring, David A.  “Guidebook to the Geology of Barringer Meteorite Crater Arizona (a.k.a. Meteor Crater).” 2nd edition ©2017, Lunar and Planetary Institute LPI Contribution No. 2040

Naqi Mohammad, Bruce Trudgill and Charles Kluth.  “A New Insight on the Mechanism of Salt Wall Collapse in Northeastern Paradox Basin, Utah.”  Search and Discovery Article #10837 (2016).  Adapted from poster presentation given at AAPG Annual Convention & Exhibition, Denver, Colorado, May 31-June 3, 2015.

Roddy, D. J., Boyce, J. M., Colton, G. W., & Dial, A. L., Jr.  “Meteor Crater, Arizona, rim drilling with thickness, structural uplift, diameter, depth, volume, and mass-balance calculations.” Lunar Science Conference, 6th, Houston, Tex., March 17-21, 1975, Proceedings. Volume 3. (A78-46741 21-91) New York, Pergamon Press, Inc., 1975, p. 2621-2644. Research supported by the U.S. Defense Nuclear Agency.

Trudgill, Bruce. (2010). “Evolution of salt structures in the northern Paradox Basin: Controls on evaporite deposition, salt wall growth and supra-salt stratigraphic architecture: Evolution of salt structures in the northern Paradox Basin.” Basin Research. 23. 208 – 238. 10.1111/j.1365-2117.2010.00478.x.

USGS Astrogeology Science Center.  Meteor Crater Sample Collection / Interactive Map.

Utah Geological Survey. GEOSIGHTS: UTAH’S BELLY BUTTON, UPHEAVAL DOME

What Scientists really mean when they say things.

May 8, 2018

What Scientists really mean when they say things.
Authoritative statements in scientific journals should not always be taken literally. I.J.Good has made a collection of them.

“It has long been known that…”
I haven’t bothered to look up the original reference.

“While it has not been possible to provide definite answers to these questions…”
The experiment didn’t work out, but I figured I could at least get a publication out of it.

“High purity …”, “Very high purity…”, “Extremely high purity…”, “Super high purity…”
Composition unknown except for the exaggerated claim of the suppliers.

“…accidentally strained during mounting”
…dropped on the floor.

“It is clear that much additional work will be required before a complete understanding…”
I don’t understand it.

“Unfortunately a quantitative theory to account for these effects has not been formulated…”
Neither does anybody else.

“It is hoped that this work will stimulate further work in the field.”
This isn’t very good, but neither is any of the others on this miserable subject.

“The agreement with the predicted curve is excellent” …good” …satisfactory” …fair.”
Fair. Poor. Doubtful. Imaginary.

“As good as could be expected considering the approximations made in the analysis.”
Non-existent.

“Of great theoretical and practical importance.”
Interesting to me.

“Three of the samples were chosen for detailed study.”
The results on the others didn’t make sense and were ignored.

“These results will be reported at a later date.”
I might possibly get around to this some time.

“Typical results are shown.”
The best results are shown.

“Although some detail has been lost in the reproduction, it is clear from the original micrograph that…”
It is impossible to tell from the micrograph.

“It is suggested…”, “It may be believed…”, “It may be that…”
I think.

“The most reliable values are those of Jones.”
He was a student of mine.

“It is generally believed that…”
A couple of other guys think so too.

“It might be argued that…”
I have such a good answer to this question that I’ll raise it.

“Correct within an order of magnitude.”
Wrong.

“Well known.”
(i) I happen to know it, or (ii) well known to some of us.

“The reason is, of course, obvious.”
(i)Not in the least, or if it really is: (ii)I was not the first to think of it, but I think I got it independently.

From “Eureka: A book of scientific anecdotes”, by Adrian Berry.
http://people.cs.uchicago.edu/~dinoj/scilies.html

Coriolis

May 7, 2018

What is most affected by Coriolis Effect is the horizontal component of the bullet trajectory. Because of the Coriolis effect, every moving object not connected to the ground is always deflected to right in the Northern Hemisphere, and always toward left in the Southern Hemisphere. The deflection is not east or west, but specifically to the right or left with reference to the shooting direction. It doesn’t matter in which direction you shoot; it is a function of latitude and average bullet speed. Its effect is maximum at the poles, and decreases as one moves toward the Equator, where it is minimal. The explanation of this phenomenon is more difficult than the explanation of Eötvös Effect, so I won’t go into it into detail.

Here’s an example of error due to Coriolis effect: firing the same .308 175gr bullet at 2700fps muzzle velocity, from a latitude of 45° in the Northern Hemisphere, the deflection at 1000yds will be of 3in to right. At the North Pole, where the effect is maximum, the deflection will be a little more than four inches. The deflection will be the same in the Southern Hemisphere, but it will be to the left, instead.

Loadout Room dot Com

Herndon Bay GPR

May 7, 2018

GPR data are acquired in time, not depth. The data are recorded and processed relative to the ground surface. In order to present the GPR transect as something resembling a geologic cross section, it has to be surface normalized or topographically corrected.

Topographic Correction of GPR Profiles Based on Laser Data
Abstract.

Data obtained by GPR (Ground Penetrating Radar) are displayed as a continuous cross-sectional profile. Surface, generally, is not flat. As a result, the image becomes distorted and the depth calculated from the surface no longer represents the true and exact position of electrically distinctive layers and objects in materials. In order to get real geologic cross section, GPR data must be corrected. This is paper discusses a new method using the color point cloud data obtained by a Vehicle-borne laser scanning system to compensate for elevation fluctuate. Elevation profile can be extracted from topographic data of survey site acquired using laser scanner, which can then be used to offset the error of GPR data. Through the discrete points in the survey line, each trace of the profile has its own elevation value showing a vertical difference from the reference profile with maximum elevation, then time shifts value of traces vertical offset versus the reference trace of profile can be obtained. At last, the results of topographic correction for radargrams that look extremely like the real geologic cross section are presented, which allows us to get a better profile interpretation and position of the objects and layers in the subsurface.

Di Zhang et al 2014 IOP Conf. Ser.: Earth Environ. Sci. 17 012251

Zhang.png

The GPR transect in Moore et al., was also corrected for terrain (surface normalization) using LiDAR.
Moore_GPR1.png

The data were acquired with a 300 ns recording window. This is approximately 5-9 m. The depths on the GPR transect are gross approximations due to the variability of the velocity field. While a surface normalized GRP transect looks like a geologic cross section, it is not. It is a geophysical approximation of a geologic cross section.

Moore_GPR2.png

On depth sections, the top of the Black Creek Group mud facies is essentially flat from the extant basin to second oldest rim. The mud facies under the oldest rim is about 1 m higher than the rest of the rims and basin.

Geoprobe core data reveal wave ravinement into the underlying Cretaceous muds, with muddy sand incorporated throughout the oldest sand rims during the initial period of high-energy lacustrine processes (Figure 4). Coring of sand rims demonstrates the scoured nature of the underlying mud facies, with an elevation drop between the older remnant basin surface to the east and the more recent basin due to scour associated with the initial period of migration and sand rim construction (Figures 3c and 4).

pg 155

[…]

The fact that Carolina bays can migrate, yet maintain their characteristic oval shape, orientation, and rim sequences demonstrates that these landforms are oriented lakes shaped by lacustrine and eolian processes. Clear evidence of basin scour into the underlying Cretaceous sandy mud, reveals that Carolina bays are capable of migrating while backfilling remnant basins with a regressive sequence of paleoshoreline deposits as the position of the basin margin changes through time.

pg 167

moorexsect.png

 

Uniformitarian Impact Craters, Part Deux: Carolina Bays Edition

April 25, 2018

Alternate title:  Carolina Bays are as antithetical to impact craters as any dents in the ground could possibly be.

Guest essay by David Middleton

Introduction

In my previous essay, we discussed the differences between uniformitarian geology and drawing cartoons on Google Earth images.  Several commentators brought up the “Carolina Bays” in defense of crater hunter cartoonists.  Carolina Bays have also been cited as evidence for the Younger Dryas Impact Hypothesis (YDIH). Since I was already in the process of composing a post on Carolina Bays, my second post on uniformitarian impact craters will focus on Carolina Bays and other obviously wind-oriented geomorphological features.

Please note: This post is not about the pros and cons of the YDIH.  Much of the evidence presented supporting the YDIH is interesting and some of it might even be compelling.  This post is about one aspect of the evidence put forward on behalf of the YDIH: the Carolina Bays.  As “evidence” of the YDIH, the Carolina Bays might even be worse than amateur crater hunters drawing cartoons on Google Earth images.  I am happy to entertain questions and even genuine debate about the geomorphology, stratigraphy and other geological/geophysical aspects of the Carolina Bays and related features.  Comments that start out with, “But how can you explain [the black mat, nanodiamonds, microspherules, the Terminal Pleistocene extinctions, Clovis culture or the lack thereof, biomass burning, etc.] will receive the following reply:

989 (1)

Non sequitur = Does not follow from.   The Carolina Bays being impact craters does not follow from other possible evidence for the YDIH.

Please also note: This is a long post and I just made it longer with the preceding paragraph.  If you don’t want to read it… then don’t.  If you don’t read it, but insist on commenting, the reply will unlikely to be courteous… Particularly if the comment is along the lines of “TL DNR.”  These sorts of comments will likely receive this sort of reply:

The Carolina Bays: Not Impact Features

First, the Arm Waving “Science”

Firestone et al. 2007 cited the Carolina Bays as potential evidence for the YDIH.

The other sample sites were in and around 15 Carolina Bays, a group of ≈500,000 elliptical lakes, wetlands, and depressions that are up to ≈10 km long and located on the Atlantic Coastal Plain (SI Fig. 7). We sampled these sites because Melton, Schriever (20), and Prouty (21) proposed linking them to an ET impact in northern North America. However, some Bay dates are reported to be >38 ka (22), older than the proposed date for the YD event.

[…]

Glass-Like Carbon.

Pieces up to several cm in diameter (Fig. 4) were found associated with the YDB and Bays, and their glassy texture suggests melting during formation, with some fragments grading into charcoal. Continuous flow isotope ratio MS analysis of the glass-like carbon from Carolina Bay M33 reveals a composition mainly of C (71%) and O (14%). Analysis by 13C NMR of the glass-like carbon from Bay M33 finds it to be 87 at.% (atomic percent) aromatic, 9 at.% aliphatic, 2 at.% carboxyl, and 2 at.% ether, and the same sample contains nanodiamonds, which are inferred to be impact-related material (see SI Fig. 11). Concentrations range from 0.01 to 16 g/kg in 15 of 15 Bays and at nine of nine Clovis-age sites in the YDB, as well as sometimes in the black mat, presumably as reworked material. Somewhat similar pieces were found in four modern forest fires studied (see SI Text, “Research Sites”).

Discussion

Age of the YDB.

The YDB at the 10 Clovis- and equivalent-age sites has been well dated to ≈12.9 ka, but the reported ages of the Carolina Bays vary. However, the sediment from 15 Carolina Bays studied contain peaks in the same markers (magnetic grains, microspherules, Ir, charcoal, carbon spherules, and glass-like carbon) as in the YDB at the nearby Topper Clovis site, where this assemblage was observed only in the YDB in sediments dating back >55 ka. Therefore, it appears that the Bay markers are identical to those found elsewhere in the YDB layers that date to 12.9 ka. Although the Bays have long been proposed as impact features, they have remained controversial, in part because of a perceived absence of ET-related materials. Although we now report that Bay sediments contain impact-related markers, we cannot yet determine whether any Bays were or were not formed by the YD event.

PNAS

“Melton, Schriever (20), and Prouty (21)” are from 1933 and 1952 respectively.  Frey (22) is from 1955.  No one noticed the Carolina Bays as a distinct morphological feature prior to the advent of aerial photography.

↵ Melton FA, Schriever W (1933) J Geol 41:52–56.Google Scholar
↵ Prouty WF (1952) Bull GSA 63:167–224.CrossRefGoogle Scholar
↵ Frey DJ (1955) Ecology 36(4):762–763.CrossRefGoogle Scholar

When Carolina Bays were first observed on aerial photos, the first hypothesis was that they were the result of a series of meteoric impacts, because they kind of look like craters.  Subsequent work has found no evidence whatsoever that the shallow depressions were the result of impacts.  And all of the age estimates make the Carolina Bays far older than the Younger Dryas.  We will revisit the geology and age determinations of the Carolina Bays later in this essay.

This really struck me…

The other sample sites were in and around 15 Carolina Bays…

“In and around”?  How about location maps?  Lat/Lon or some other location data?

Then they cite the two papers from 60-80 years ago as a basis to investigate the Carolina Bays as potential impact sites, ignore everything published since 1955 and conclude with:

Although we now report that Bay sediments contain impact-related markers, we cannot yet determine whether any Bays were or were not formed by the YD event.

Of course you can “determine whether any Bays were or were not formed by the YD event.”  Because there is no evidence to support this idea.  Even if their “impact-related markers” constituted evidence for the YDIH, an air-bursting bolide*, 12,900 years ago would have showered the Carolina Bays with “impact-related” materials.

*Yes, I know that “air-bursting bolide” is redundant.

Impact event

The cometary impact hypothesis of the origin of the bays was popular among earth scientists of the 1940s and 50s. After considerable debate and research, geologists determined the depressions were both too shallow and lacking in any evidence for them to be impact features. Reports of magnetic anomalies turned out not to show consistency across the sites. There were no meteorite fragments, shatter cones or planar deformation features. None of the necessary evidence for hypervelocity impacts was found. The conclusion was to reject the hypothesis that the Carolina Bays were created by impacts of asteroids or comets (Rajmon 2009).

A new type of extraterrestrial impact hypothesis was proposed as the result of interest by both popular writers and professional geologists in the possibility of a terminal Pleistocene extraterrestrial impacts, including the Younger Dryas impact hypothesis. It said that the Carolina Bays were created by a low density comet exploding above or impacting on the Laurentide ice sheet about 12,900 years ago.[29] However, this idea has been discredited by OSL dating of the rims of the Carolina bays, paleoenvironmental records obtained from cores of Carolina bay sediments, and other research that shows that many of them are as old as, or older than, 60,000 to 140,000 BP.[13][14][15][30][31]

Wikipedia

The Wikipedia entry is surprisingly quite good… Probably because there’s no Gorebal Warming or any other left-wing environmental aspect to the Carolina Bays and/or the YDIH.

From Firestone et al., 2007 SI Text…

Carolina BaysThe Carolina Bays are a group of »500,000 highly elliptical and often overlapping depressions scattered throughout the Atlantic Coastal Plain from New Jersey to Alabama (see SI Fig. 7). They range from ≈50 m to ≈10 km in length (10) and are up to ≈15 m deep with their parallel long axes oriented predominately to the northwest. The Bays have poorly stratified, sandy, elevated rims (up to 7 m) that often are higher to the southeast. All of the Bay rims examined were found to have, throughout their entire 1.5- to 5-m sandy rims, a typical assemblage of YDB markers (magnetic grains, magnetic microspherules, Ir, charcoal, soot, glass-like carbon, nanodiamonds, carbon spherules, and fullerenes with 3He). In Howard Bay, markers were concentrated throughout the rim, as well as in a discrete layer (15 cm thick) located 4 m deep at the base of the basin fill and containing peaks in magnetic microspherules and magnetic grains that are enriched in Ir (15 ppb), along with peaks in charcoal, carbon spherules, and glass-like carbon. In two Bay-lakes, Mattamuskeet and Phelps, glass-like carbon and peaks in magnetic grains (16-17 g/kg) were found ≈4 m below the water surface and 3 m deep in sediment that is younger than a marine shell hash that dates to the ocean highstand of the previous interglacial.

Modern Fires. Four recent modern sites were surface-sampled. Two were taken from forest underbrush fires in North Carolina that burned near Holly Grove in 2006 and Ft. Bragg in 2007. Trees mainly were yellow pine mixed with oak. There was no evidence of carbon spherules and only limited evidence of glass-like carbon, which usually was fused onto much larger pieces of charcoal. The glass-like carbon did not form on oak charcoal, being visible only on pine charcoal, where it appears to have formed by combustion of highly flammable pine resin.

Two surface samples also were taken from recent modern fires in Arizona; they were the Walker fire, which was a forest underbrush fire in 2007 and the Indian Creek Fire near Prescott in 2002, which was an intense crown fire. Trees mainly were Ponderosa pine and other species of yellow pine. Only the crown fire produced carbon spherules, which were abundant (≈200 per kg of surface sediment) and appeared indistinguishable from those at Clovis sample sites. Both sites produced glass-like carbon fused onto pine charcoal.

PNAS SI

All told, Firestone et al., 2007 wasn’t batschist crazy.  There was a fair amount of arm waving; but they didn’t really drift off into Art Bell land.

Next, the Science Fiction

Cue the theme from Twilight Zone.  Firestone 2009 was essentially a variation of Firestone et al., 2007, with a few bits of SyFy tossed in,

West also investigated sediment from 15 Carolina Bays, elliptical depressions found along the Atlantic coast from New England to Florida (Eyton and Parkhurst, 1975), whose parallel major axes point towards either the Great Lakes or Hudson Bay as seen in Fig. 3. Similar bays have tentatively been identified in Texas, New Mexico, Kansas, and Nebraska (Kuzilla, 1988) although they are far less common in this region. Their major axes also point towards the Great Lakes. The formation of the Carolina Bays was originally ascribed to meteor impacts (Melton and Schriever, 1933) but when no meteorites were found they were variously ascribed to marine, eolian, or other terrestrial processes.

West found abundant microspherules, carbon spherules, glass-like carbon, charcoal, Fullerenes, and soot throughout the Carolina Bays but not beneath them as shown in Fig. 4. Outside of the Bays these markers were only found only in the YDB layer as in other Clovis-age sites.

Figure 3. The Carolina Bays are »500,000 elliptical, shallow lakes, wetlands, and depressions, up to »10 km long, with parallel major axes (see inset) pointing toward the Great Lakes or Hudson Bay. Similar features found in fewer numbers in the plains states also point towards the Great Lakes. These bays were not apparent topographical features until the advent of aerial photography.

Figure 4. At two sandy Carolina Bays magnetic grains, carbon spherules and glass-like carbon (vitreous charcoal) are found distributed throughout the Bay sediment.

[…]

Glass-like Carbon: Pieces of glass-like carbon, up to several cm in diameter, have been found in the YDB layer at most sites with concentrations in sediment ranging from 0.01- 16 g/kg. Glass-like carbon doesn’t exist naturally and the man-made varieties are shown to have a structure similar to Fullerenes (Harris, 2004). Nanodiamonds were found in a Carolina Bay sample. The PGAA analysis of glass-like carbon sample from the Carolina Bays is shown in Table 2. It is 90 wt.% C and analysis by 13C NMR indicated that it is 87 at.% aromatic, 9 at.% aliphatic, 2 at.% carboxyl, and 2 at.% ether. PGAA shows that the sample contains significant amounts of SiO2 (4.8 wt.%) and Al2O3 (1.0 wt.%), probably from contamination by YDB sediment. A significant quantity of nitrogen (0.66 wt.%) and trace amounts of TiO2 (0.067 wt.%) and FeO (0.08 wt.%) were found. The ratio of TiO2/FeO=0.8 is comparable to that found in magnetic grains and microspherules.

A sample from the Carolina Bays shown in Fig.8 was found to grade from glass-like carbon at one end to wood on the other. The wood was identified by Alex Wiedenhoft (private communication) as Yellow Pine, a species native to the Carolinas at the time of the YDB. Glass-like carbon can be produced by the thermal decomposition of cellulose at 3200 °C (Kaburagi et al. 2005) but such high temperatures would normally consume the entire tree. The composition of this sample is consistent with a tree that was impacted by a rapidly moving, high-temperature shockwave that produced glass-like carbon on only one side as it passed. The anoxic conditions following the shock wave would have stopped further burning.

Figure 8. A carbon sample from a Carolina Bay that varies from the shiny, melted appearance of glass-like carbon at the top to Yellow Pine on the bottom. This can occur if the sample were exposed to the 3200 ° shockwave that “melted” one side of a tree but failed to destroy it entirely due to anoxic conditions behind the shockwave.

Radiocarbon dates for six glass-like carbon samples from the Carolina Bays are summarized in Table 2. Dates range from 685-8455 yr BP, much younger than the age inferred from their statigraphic context. The discrepancies are not as large as for the carbon spherules suggesting that these samples are predominantly composed of tree cellulose with additional 14C-rich carbon mixed into the glass-like carbon by the shockwave.

Journal of Cosmology

Radiocarbon dates for six glass-like carbon samples from the Carolina Bays are summarized in Table 2 [Table 3?]. Dates range from 685-8455 yr BP, much younger than the age inferred from their statigraphic context. The discrepancies are not as large as for the carbon spherules suggesting that these samples are predominantly composed of tree cellulose with additional 14C-rich carbon mixed into the glass-like carbon by the shockwave.

The 14C dates for the “six glass-like carbon samples from the Carolina Bays” range from 685-8,455 years before present (1950 AD).  Even after calibrating the 14C dates to calendar years, the bits of burnt would are way too young to be evidence for the YDIH.

14C ky Calendar ky
9.6 11
10.2 12
11 13
12 14
12.7 15
13.3 16
14.2 17
15 18
15.9 19
16.8 20
17.6 21
18.5 22
19.3 23
20 24
0.685 0.307
8.455 9.824

Radiocarbon Year Conversion

In Firestone et al., 2007 they allowed for the possibility that the glassy bits of burnt wood could have been the product of forest fires.  Two years later and flying solo, the glassy bits of wood had been “exposed to the 3200 ° shockwave that “melted” one side of a tree but failed to destroy it entirely due to anoxic conditions behind the shockwave.”  °F or °C?  Not that it matters.

Even if the glassy bits of wood were the result of some sort of air-bursting bolide, it doesn’t constitute evidence for the Carolina Bays being impact features, much less evidence that they were suddenly created at the Younger Dryas Boundary (YDB).  The Bay ridges range from 27 ka to well over 100 ka.  The basin fill can be as young as a few hundred years old.  Stuff falling out of the sky 12,900 years ago could have easily been buried in Carolina Bays, even in the ridges.

This has become one of the most oft-repeated memes among YDIH proponents:

West also investigated sediment from 15 Carolina Bays, elliptical depressions found along the Atlantic coast from New England to Florida (Eyton and Parkhurst, 1975), whose parallel major axes point towards either the Great Lakes or Hudson Bay as seen in Fig. 3.

It’s often accompanied by variations of this image:

The wrongness of the image above is spectacular.

Carolina Bays and Similar Features Do Not Point at the Great Lakes or Hudson Bay

There are several recent detailed USGS surficial geology quadrangles in which Carolina Bays and comparable features have been mapped in detail.   Almost none of the “parallel major axes point towards either the Great Lakes or Hudson Bay.”  If the major axes were parallel (as many are in the Carolinas), they couldn’t all point at any common feature.

These examples are from the Surficial Geologic Map of the Elizabethtown 30′ × 60′ Quadrangle, North Carolina (Weems et al., 2011).

Elizabethtown2

Elizabethtown 7.5 minute quadrangle, surficial geology, Carolina Bay features generally have azimuths of 305-320° azimuths. As does much of the drainage and underlying structural geology.  USGS

Zooming in on one of the more prominent bays:

WarwickMillBay

Warwick Mill Bay. 310° azimuth.

Elizabethtown5

Map unit legend.

Big Juniper Bay and cross section B-B’…

Elizabethtown4

Elizabethtown6

Note that Qwm fills a depression in Qwb and Qhm fills depressions in Qwm and Qwb.

LiDAR images yield a similar picture:

RobesonLiDAR

“LIDAR elevation image of 300 square miles (800 km2) of Carolina bays in Robeson County, N.C.” (Wikipedia).

HerndonBayEllipse

LiDAR image of Herndon Bay. (Modified after Moore et al., 2016).

The Carolina Bays have a western cousin: Nebraska’s Rainwater Basins;  where we have a brand new, detailed map of a series of Rainwater Basins: Surficial Geology of the Fairmont 7.5 Minute Quadrangle, Nebraska (Hanson et al., 2017).

FairmontQuad

Azimuths of Rainwater Basins in the Fairmont 7.5 minute quadrangle range from 10-87°. The large Rainwater Basin in the south-central portion of the map appears to have migrated to the northwest. (Modified after Hanson et al., 2017)

FairmontQuad_Sec16

This Rainwater Basin appears to have migrated from Section 22, to Section 15/21, to Section 16.

FairmontQuad_legend

Map unit legend for Fairmont quadrangle.

Put it all to together and we have:

USGS_Map

Maybe the bolides exploded over Nebraska and North Carolina, bombarding the Great Lakes and Saskatchewan with eolian debris  (/SARC)

I could pull geologic maps all day long, and the results would only get worse for the Carolina Bays being evidence for the YDIH.  Which makes me wonder if Firestone ever looked at any geologic maps.

The older, lower resolution Quaternary geologic map of the Savannah 4 degrees x 6 degrees quadrangle (Colquhoun et al., 1987) covers all of South Carolina and much of Georgia and North Carolina.  While most of the Carolina Bays trend from NW-SE, some trend from N-S, some aren’t even particularly elliptical.

Savannah

Portion of Savannah 4×6° quadrangle. Red dashed ovals indicate N-S trending Carolina Bays.

Why Would Anyone Expect Impact Craters to be Elliptical?

Why are impact craters always round? Most incoming objects must strike at some angle from vertical, so why don’t the majority of impact sites have elongated, teardrop shapes?

Gregory A. Lyzenga, associate professor of physics at Harvey Mudd College, replies:
“When geologists and astronomers first recognized that lunar and terrestrial craters were produced by impacts, they surmised that much of the impacting body might be found still buried beneath the surface of the crater floor. (Much wasted effort was expended to locate a huge, buried nickel-iron meteorite believed to rest under the famous Barringer meteor crater near Winslow, Ariz.) Much later, however, scientists realized that at typical solar system velocities–several to tens of kilometers per second–any impacting body must be completely vaporized when it hits.

“At the moment an asteroid collides with a planet, there is an explosive release of the asteroid’s huge kinetic energy. The energy is very abruptly deposited at what amounts to a single point in the planet’s crust. This sudden, focused release resembles more than anything else the detonation of an extremely powerful bomb. As in the case of a bomb explosion, the shape of the resulting crater is round: ejecta is thrown equally in all directions regardless of the direction from which the bomb may have arrived.

“This behavior may seem at odds with our daily experience of throwing rocks into a sandbox or mud, because in those cases the shape and size of the ‘crater’ is dominated by the physical dimensions of the rigid impactor. In the case of astronomical impacts, though, the physical shape and direction of approach of the meteorite is insignificant compared with the tremendous kinetic energy that it carries.

[…]

Scientific American

“Only roughly 5% of all craters (greater than 1 km in diameter) observed on Mars, Venus, and the Moon have elliptical shapes with an ellipticity of 1.1 or greater”

Planetary and Space Science
Volume 135, January 2017, Pages 27-36

Oblique impact cratering experiments in brittle targets: Implications for elliptical craters on the Moon

Tatsuhiro Michikami, Axel Hagermann, Tomokatsu Morota, Junichi Haruyama, Sunao Hasegawa

[…]

Only roughly 5% of all craters (greater than 1 km in diameter) observed on Mars, Venus, and the Moon have elliptical shapes with an ellipticity of 1.1 or greater, where the crater’s ellipticity is defined as the ratio of its maximum and minimum rim-to-rim diameters (Bottke et al., 2000). Although elliptical impact craters may be rare on solid-surface planetary bodies, a better understanding of the formation of elliptical craters would contribute to our overall understanding of impact cratering. For instance, it is well-known that crater size depends on impact angle (e.g., Elbeshausen et al., 2009).

[…]

Fig. 2. Photographs of elliptical craters created by impacts into targets without a cavity at various impact angles. Projectiles came from the left of the photograph.

Planetary and Space Science

Do any of the simulated craters above look even remotely like Carolina Bay features?  Many Carolina Bay features are very smooth ellipses, often with ellipticities >1.5.

“Elliptical impact craters are rare among the generally symmetric shape of impact structures on planetary surfaces.”

The transition from circular to elliptical impact craters

Dirk Elbeshausen, Kai Wünnemann, Gareth S. Collins
First published: 15 October 2013 https://doi.org/10.1002/2013JE004477

Abstract

[1] Elliptical impact craters are rare among the generally symmetric shape of impact structures on planetary surfaces. Nevertheless, a better understanding of the formation of these craters may significantly contribute to our overall understanding of hypervelocity impact cratering. The existence of elliptical craters raises a number of questions: Why do some impacts result in a circular crater whereas others form elliptical shapes? What conditions promote the formation of elliptical craters? How does the formation of elliptical craters differ from those of circular craters? Is the formation process comparable to those of elliptical craters formed at subsonic speeds? How does crater formation work at the transition from circular to elliptical craters? By conducting more than 800 three‐dimensional (3‐D) hydrocode simulations, we have investigated these questions in a quantitative manner. We show that the threshold angle for elliptical crater generation depends on cratering efficiency. We have analyzed and quantified the influence of projectile size and material strength (cohesion and coefficient of internal friction) independently from each other. We show that elliptical craters are formed by shock‐induced excavation, the same process that forms circular craters and reveal that the transition from circular to elliptical craters is characterized by the dominance of two processes: A directed and momentum‐controlled energy transfer in the beginning and a subsequent symmetric, nearly instantaneous energy release.

1 Introduction

[2] The vast majority of impact craters on planetary surfaces, moons, and asteroids are circular in plan. Only 5% of the crater record—at least on Mars, Moon, and Venus—shows an elliptical morphology [see e.g., Schultz and Lutz‐Garihan1982Bottke et al., 2000]. Elliptical craters result from impacts that occur at a very shallow angle of incidence. If a cosmic object (projectile) strikes the planetary surface (target) at an angle smaller than a certain threshold angle, the resulting crater shape deviates from a circular symmetry and becomes elongated in the direction of impact. The ellipticity of the crater increases with decreasing impact angle [Gault and Wedekind1978]. From the point of view of celestial mechanics, moderately oblique impacts are the norm and the most likely angle of incidence is 45°. Half of all impacts occur at even shallower angles and only ~5% of all impacts strike the target at an angle of 12° or less [see Gilbert1893Shoemaker1962]. Accordingly, Bottke et al. [2000] concluded that the threshold angle to form elliptical craters must be 12° in order to match the observational record that 5% of all craters have an elliptical morphology.

[3] More detailed studies both by laboratory experiments [Gault and Wedekind1978Christiansen et al., 1993Burchell and Mackay1998] and numerical simulations [Collins et al., 2011] revealed that the angle below which elliptical craters form, the so‐called critical angle, depends on the properties of the target material. Based on numerical models of oblique crater formation and results from laboratory experiments, Collins et al. [2011] proposed that the critical angle for the formation of elliptical craters is a function of cratering efficiency, here defined as the ratio of crater and projectile diameter.

[…]

[11] Ellipticity ε is defined as the length of a crater divided by its width. To distinguish a circular from an elliptical shape, some sort of threshold value has to be defined for ε. This is a relatively arbitrary choice; however, to stay in line with previous studies on this subject, we follow the definition by Bottke et al. [2000], who consider craters as elliptical if the ellipticity ε is larger or equal to 1.1.

[…]

JGR

Elbeshausen et al., 2013, Figure 5
Ellipticity as a function of the impact angle and cohesion (projectile diameter L = 500 m, friction coefficient f = 0.7, impact velocity is U = 8 km/s).

The Pleistocene substratum of Carolina Bays and Rainwater Basins is largely unconsolidated sand.  Even Pleistocene “sandstone” buried at depths of 20,000′ in the Gulf of Mexico tends to be poorly consolidated (friable in geologeese).  Sand control is a major well completion issue in the Gulf of Mexico: Producing the oil & gas without filling up the wellbore with sand is often a challenge.

Herndon Bay is particularly elliptical.  If we assume that the substratum is poorly consolidated sand, we find:

  • Cohesion of sand = 0.0 MPa
  • Herndon Bay ellipticity = 1.8

The impact angle would have had to have been about 1-2° and the meteoric object would have had to have impacted intact to generate such an elliptical crater.  I don’t think there is an adequate adjective to tack onto “unlikely” to cover this bit.  The next bit gets better.

There are 190 documented, confirmed impact craters on Earth (well, 189 if you don’t count Upheaval Dome).  There are possibly 500,000 Carolina Bay type features on Earth, probably many more.

If only 5% of craters on Mars, the Moon, and Venus exhibit an elliptical morphology, generally defined as an ellipticity >1.1… What are the odds that 99.96% of the craters on Earth would be elliptical, with ellipticities often exceeding 1.5?

Now that we’ve demonstrated that Carolina Bays and similar features aren’t mysteriously pointing at the Great Lakes or Hudson Bay, were formed thousands of years prior to the YDB, that elliptical craters are rare and that it would be almost impossible for Carolina Bays to be elliptical impact craters, let’s look at one of the most well-documented Carolina Bays.

Herndon Bay

Read THE_QUATERNARY_EVOLUTION_OF_HERNDON_BAY.  The full text is available.  It’s the most thorough geological and geophysical investigation of a Carolina Bay feature I have been able to locate.

ABSTRACT

Geological investigations of Herndon Bay, a Carolina bay in the Coastal Plain of North Carolina (USA), provide evidence for rapid basin scour and migration during Marine Isotope Stage (MIS) 3 of the late Pleistocene. LiDAR data show a regressive sequence of sand rims that partially backfill the remnant older portions of the bay, with evidence for basin migration more than 600 meters to the northwest. Basin migration was punctuated by periods of stability and construction of a regressive sequence of sand rims with basal muddy sands incorporated into the oldest rims. Single grain OSL ages place the initial formation of each sand rim from oldest to most recent as ca. 36.7 +/- 4.1, 29.6 +/- 3.1, and 27.2 +/- 2.8 ka. These ages indicate that migration and rim construction was coincident with MIS 3 through early MIS 2, a time of rapid oscillations in climate. The fact that Carolina bay basins can migrate, yet maintain their characteristic shape and orientation, demonstrates that Carolina bays are oriented lakes that evolved over time through lacustrine and eolian processes. This research also indicates that Carolina bays can respond rapidly during periods of climatic transition such as Dansgaard-Oeschger or Heinrich events.

Figure 3 from Moore et al., 2016:

Moore_Fig3

Figure 3. LiDAR imagery and elevation profiles for Herndon Bay: a) 3D LiDAR view [20 percent exaggeration], b) LiDAR planview showing elevation, GPR transect [white line], and Geoprobe core locations, c) and d) elevation profiles showing Geoprobe® core and OSL sample locations/ depth. The LiDAR data are provided by the North Carolina Floodplain Mapping Program (http:// http://www.ncfloodmaps.com/) and were collected using 3-5 meter point spacing and a vertical accuracy of less than or equal to 20 cm Root Mean Squares Error (RMSE).

Cores were taken from the the four ridges (HB1, HB2, HB3 and HB4).  The latitude and longitude of each core is clearly identified and the depth from which the three Optically-Stimulated Luminescence (OSL) samples were extracted are clearly documented.  The sandy rims become progressively younger as the bay migrated from SE to NW.  It’s kind of difficult for impact craters to migrate.

The youngest sandy rim, HB1, was deposited about 15,000 years before the Younger Dryas.

Moore_Fig9

Figure 9. Single grain OSL age estimates (computed at one-sigma) for sand rims plotted over the GISP2 Oxygen Isotope curve (Ice core data provided by the National Snow and Ice Data Center, University of Colorado, Boulder [http://nsidc.org/] and the WDC-A for Paleoclimatology, National Geophysical Data Center [http://www.ncdc.noaa.gov/paleo/wdc-paleo.html], Boulder, Colorado), Grootes and others, 1993. Dansgaard-Oeschger events (2-8) are indicated by number (Dansgaard and others, 1993).

It’s funny… Since the mid-1990’s, Optically-Stimulated Luminescence (OSL) has literally revolutionized Quaternary geology and geoarchaeology.

What is OSL?

OSL is an acronym for Optically-Stimulated Luminescence.

Optically-Stimulated Luminescence is a late Quaternary dating technique used to date the last time quartz sediment was exposed to light. As sediment is transported by wind, water, or ice, it is exposed to sunlight and zeroed of any previous luminescence signal. Once this sediment is deposited and subsequently buried, it is removed from light and is exposed to low levels of natural radiation in the surrounding sediment. Through geologic time, quartz minerals accumulate a luminescence signal as ionizing radiation excites electrons within parent nuclei in the crystal lattice. A certain percent of the freed electrons become trapped in defects or holes in the crystal lattice of the quartz sand grain (referred to as luminescent centers) and accumulate over time (Aitken, 1998).

[…]

Utah State University

I wonder how many detractors of uniformitarianism also reject OSL… hmmm?

Oriented Lakes and Other Wind-Oriented Features

Maybe these impact craters are pointing at Tunguska? (/Sarc)

The oriented lakes of Tuktoyaktuk Peninsula, Western Arctic Coast, Canada: a GIS‐based analysis

M. M. Côté C. R. Burn
First published: 25 March 2002

Abstract

The orientation, size and shape of 578 lakes on Tuktoyaktuk Peninsula were obtained from 1 : 250 000 Canadian National Topographic Survey map sheets, using ArcView geographic information system. These lakes are outside the glacial limits in a tundra plain with <15m relief. The lakes range from 20 to 1900 ha, and have mean orientation N07 °E, with standard error 1.6°. The maps show 145 former lake basins, with lakes inset in 130 of these. The mean orientations of the basins and inset lakes are not statistically different from each other or the general population. Several theories have been proposed for the origin of the oriented lakes, and one theory attributes the orientation to cross winds establishing currents that preferentially erode the ends of the lakes.

[…]

Permafrost and Periglacial Processes

Or, maybe, oriented lacustrine features are fairly common occurrences…

Growth Secrets of Alaska’s Mysterious Field of Lakes

Mari N. Jensen
June 27, 2005

The thousands of oval lakes that dot Alaska’s North Slope are some of the fastest-growing lakes on the planet. Ranging in size from puddles to more than 15 miles in length, the lakes have expanded at rates up to 15 feet per year, year in and year out for thousands of years. The lakes are shaped like elongated eggs with the skinny ends pointing northwest.

How the lakes grow so fast, why they’re oriented in the same direction and what gives them their odd shape has puzzled geologists for decades. The field of lakes covers an area twice the size of Massachusetts, and the lakes are unusual enough to have their own name: oriented thaw lakes.

“Lakes come in all sizes and shapes, but they’re rarely oriented in the same direction,” said Jon Pelletier, an assistant professor of geosciences at The University of Arizona in Tucson.

Now Pelletier has proposed a new explanation for the orientation, shape and speed of growth of oriented thaw lakes. The lakes’ unusual characteristics result from seasonal slumping of the banks when the permafrost thaws abruptly, he said. The lakes grow when rapid warming melts a lake’s frozen bank, and the soggy soil loses its strength and slides into the water. Such lakes are found in the permafrost zone in Alaska, northern Canada and northern Russia.

Previous explanations for the water bodies’ shape and orientation invoked wind-driven lake circulation and erosion by waves.

[…]

University of Arizona

Even though the “thousands of oval lakes that dot Alaska’s North Slope” are oriented perpendicular to the prevailing wind direction, Pelletier’s model indicates that the cause is seasonal permafrost melting.  Whether wind-driven or permafrost driven, they aren’t impact driven.

The fact is that the cause of oriented lake features is not known with any degree of certainty.  However, meteoric impacts don’t fit any of the observations.  It does appear that wind patterns play a significant role; but other local factors are also very important.

Just for grins, here’s another wind-oriented feature:

Mobile1

Isochore Map of Porous Norphlet Sandstone. (Frost 2010). Pointing at the Great Lakes?

Unfortunately, no.  The Norphlet points at Minneapolis…

Mobile2

“Just a bit outside”… And 160 million years too early… And 20,000′ too deep.

The Norphlet is an Upper Jurassic formation deposited under very arid conditions.  The Upper Norphlet is eolian and characterized by “Seif” dunes.  Under Mobile Bay, the Norphlet is at a depth of about 20,000’… Yet, through the miracle of uniformitarian geology, it was relatively easy to characterize the Norphlet as an eolian sequence, rather than impact craters or Gulf of Mexican Ignimbrites.

 

 

 

 

 

https://esajournals.onlinelibrary.wiley.com/doi/abs/10.2307/1931316

https://esajournals.onlinelibrary.wiley.com/doi/abs/10.2307/1934924

https://www.sciencedirect.com/science/article/pii/0033589480900289

http://mcadams.posc.mu.edu/home.htm

https://nationalmap.gov/small_scale/a_plss.html
.

Norphlet

Norphlet_isochore

 https://www.sciencedirect.com/science/article/pii/S0264817217305020

Oriented lakes of Alaska

https://uanews.arizona.edu/story/growth-secrets-alaskas-mysterious-field-lakes

https://scholarworks.uni.edu/cgi/viewcontent.cgi?article=2656&context=pias

Nebraska Rainwater Basins

https://hprcc.unl.edu/datasets.php?set=WindRose#

http://snr.unl.edu/csd-esic/download/geologysoils/digitalgeologicmapscleaned/Fairmont/Fairmont_Quad.pdf

Paper No. 180-0

NEBRASKA’S CAROLINA BAYS

ZANNER, C. William, School of Natural Resource Sciences, Univ of Nebraska, 133 Keim Hall, Lincoln, NE 68583-0915, bzanner2@unl.edu and KUZILA, Mark S., Conservation and Survey Division, University of Nebraska, 113 Nebraska Hall, Lincoln, NE 68583-0517

The Carolina Bays of the Atlantic Coastal Plain are one of the more enigmatic geomorphological features in North America. These elliptical depressions occur in a variety of sizes, are oriented NW-SE, and have rims most visible on the southeast edge. They have often inspired flights of fancy as scientists and the public have sought ways to explain them. Part of the fascination stems from the perception that they are unique to the Coastal Plain. South of the Platte River in east central Nebraska, USGS DOQs reveal a multitude of oval shaped features that share SW-NE orientation. They occur in a variety of sizes and have rims on the southeast edge. Locally they are called Rainwater Basins. Bays occur in Coastal Plain sandy sediments; however, the Basins of Nebraska occur in a loess-mantled landscape. Orientation of Bays and Basins is opposite, but both are perpendicular to regional prevailing wind directions. Prior work of Kuzila suggested that the Nebraska Basins exist where a loess dated at ~27000 radiocarbon years before present provides a pre-existing topography. Soil survey maps of the area show that some rims of the Basins are sandy. Cores from the area indicate that a sandy landscape was buried by loess. Upper parts of these sandy deposits are well sorted; fluvial sands and gravels occur below these sorted sands. Using coring and OSL dating we are currently documenting the age of this sandy surface. Our hypothesis is that the Basins on the current land surface originally formed as blowouts or low spots in abandoned Platte River fluvial sands and gravels. The ~27000 radiocarbon years and later loess actually draped a pre-existing topography formed in these sands. We also offer that these features would be recognized as an analog of the Carolina Bays if not for their loess cover. This suggests that Carolina Bays are not unique features, and any explanation for their existence should also help explain Nebraska’s Rainwater Basins.
GSA Annual Meeting, November 5-8, 2001
General Information for this Meeting
Session No. 180
Quaternary Geology/Geomorphology (Posters) II
Hynes Convention Center: Hall D
1:30 PM-5:30 PM, Thursday, November 8, 2001

https://gsa.confex.com/gsa/2001AM/finalprogram/abstract_22324.htm

https://ngmdb.usgs.gov/Prodesc/proddesc_9209.htm

THE_QUATERNARY_EVOLUTION_OF_HERNDON_BAY

Radiocarbon and Luminescence Dating at Flamingo Bay (38AK469): Implications for Site Formation Processes and Artifact Burial at a Carolina Bay

Elizabethtown

Weems, R.E., Lewis, W.C., and Crider, E.A, 2011, Surficial geologic map of the Elizabethtown 30′ × 60′ quadrangle, North Carolina: U.S. Geological Survey Open-File Report 2011–1121, 1 sheet, scale 1:100,000.

Elizabethtown7HerndonBay4HerndonBay2

References

Côté, M. M. and Burn, C. R. (2002), The oriented lakes of Tuktoyaktuk Peninsula, Western Arctic Coast, Canada: a GIS‐based analysis. Permafrost Periglac. Process., 13: 61-70. doi:10.1002/ppp.407

Elbeshausen, D., Wünnemann, K., Collins, G.S., 2013. The transition from circular to elliptical impact craters. Journal of Geophysical Research Planets 118, 2295–2309.

Firestone,  R. B., A. West, J. P. Kennett, L. Becker, T. E. Bunch, Z. S. Revay, P. H. Schultz, T. Belgya, D. J. Kennett, J. M. Erlandson, O. J. Dickenson, A. C. Goodyear, R. S. Harris, G. A. Howard, J. B. Kloosterman, P. Lechler, P. A. Mayewski, J. Montgomery, R. Poreda, T. Darrah, S. S. Que Hee, A. R. Smith, A. Stich, W. Topping, J. H. Wittke, W. S. Wolbach.  Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling.  Proceedings of the National Academy of Sciences Oct 2007, 104 (41) 16016-16021; DOI: 10.1073/pnas.0706977104

Firestone, R.B. The Case for the Younger Dryas  Extraterrestrial Impact Event: Mammoth, Megafauna, and Clovis Extinction, 12,900 Years Ago.  Journal of Cosmology, 2009, Vol 2, pages 256-285.  Cosmology, October 27, 2009

Frost, Weldon G.  The Somewhat Accidental Discovery of the Mobile Bay Gas Field: A Story of Perseverance and Good Fortune.   Search and Discovery Article #110133 (2010).  Posted June 16, 2010

Hanson, P. R.,  A. R. Young, A. K. Larsen, L. M. Howard1, and J. S. Dillon.  Surficial Geology of the Fairmont 7.5 Minute Quadrangle, Nebraska. USGS 2017.

Michikami, T.,  A. Hagermann, T. Morota, J. Haruyama, S. Hasegawa.  Oblique impact cratering experiments in brittle targets: implications for elliptical craters on the Moon. Planet Space Sci, 135 (2017), pp. 27-36

Moore, Christopher & Brooks, Mark & Mallinson, David & Parham, Peter & Ivester, Andrew & K. Feathers, James. (2016). The Quaternary evolution of Herndon Bay, a Carolina Bay on the Coastal Plain of North Carolina (USA): implications for paleoclimate and oriented lake genesis. Southeastern Geology. 51. 145-171.

Weems, R.E., Lewis, W.C., and Crider, E.A, 2011, Surficial geologic map of the Elizabethtown 30′ × 60′ quadrangle, North Carolina: U.S. Geological Survey Open-File Report 2011–1121, 1 sheet, scale 1:100,000.

Zanner, C. William.  Nebraska’s Carolina Bays.  GSA Annual Meeting, November 5-8, 2001.