A core project to watch

On March 6, 2012 when Isabel Israde-Alcántara et al. reported Evidence from central Mexico supporting the Younger Dryas extraterrestrial impact hypothesis their new paper in PNAS immediately superseded Firestone et al. (2007) as the flagship paper for the Younger Dryas impact hypothesis. They reported a 10 cm thick impact layer in Lake Cuitzeo that’s similar to the Cretaceous/Tertiary boundary which marks the impact event that’s blamed for the extinction of the dinosaurs 65 million years ago.

Meanwhile Terry Jones of Cal Poly has reported that the California archaeological record is consistent with Younger Dryas disruptive event. He tells us that there is  a 700 year gap in human occupation in California beginning at the start of the Younger Dryas cooling. Also D.J. Kennet et al. reported Wildfire and abrupt ecosystem disruption on California’s Northern Channel Islands at the Ållerød–Younger Dryas boundary (13.0–12.9 ka)

And in central California some of the foothills of the western slope of the Sierra Nevada mountains are blanketed with pristine burnt facies that can’t be attributed to terrestrial volcanism.

We have a bit of a mystery here in California concerning what kind of catastrophe happened at the beginning of the Younger Dryas Cooling. There is compelling evidence that it is related to a large cluster airburst event that hit the western half of the continent 12,900 YA. And there is currently a core drilling project underway in northern California that has the potential shed a great deal of light on things.

Scientists core into Clear Lake to explore past climate change

By Robert Sanders, Media Relations | May 3, 2012

BERKELEY —

University of California, Berkeley, scientists are drilling into ancient sediments at the bottom of Northern California’s Clear Lake for clues that could help them better predict how today’s plants and animals will adapt to climate change and increasing population.

UC Berkeley professor Cindy Looy and graduate student Liam Reidy explain how drilling into Clear Lake can reveal the consequences of past climate change, and help us predict the future consequences of global warming. (Video produced by Roxanne Makasdjian)

The lake sediments are among the world’s oldest, containing records of biological change stretching back as far as 500,000 years.

The core drilling is part of a unique, multifaceted effort at UC Berkeley to determine how Earth’s flora and fauna responded to past changes in climate in order to improve models that project how life on Earth will adapt to today’s environmental pressures. What the researchers learn from their look-back in time will be crucial for state or local planners clamoring for better predictive tools to guide policies crucial to saving ecosystems threatened by climate change.

“We are reconstructing the past to better forecast the future, because we need to know what’s coming in order to adequately prepare for it,” said project leader Cindy Looy, UC Berkeley assistant professor of integrative biology.

Looy and 16 other UC Berkeley faculty members – including paleontologists, pollen experts, botanists, ecologists and climate modeling experts – will examine the lake cores for pollen grains, charcoal and fresh-water organisms going back at least 130,000 years, long before humans arrived in the area. Using isotope and chemical analysis as well as carbon dating, the researchers will obtain a long series of detailed snapshots – ideally, every 10 years – of the plant and animal communities in the Clear Lake area and how the communities changed in response to “natural” global warming events. The analysis will also provide a measure of the temperature, oxygen content and nutrient levels of the lake, which reflect rainfall and water level.

One way to check our predictions is to go back in time to a state very similar to today, with the same plants and animals and about the same temperature. The fossilized plant and animal remains from Clear Lake will give us a baseline for what this region of California looked like under similar climatic conditions, and when it was colder or warmer. We use that information to fine-tune predictive models being developed today,” Looy said. “Rates of global warming almost as fast as what we see today last happened during the shift from the last glacial to the current interglacial roughly 12,000 years ago, so that is one time interval we will focus on.”

Clear Lake, which is about 19 miles by 8 miles at its widest, is located about 100 miles north of San Francisco.

Focusing on two glacial-to-interglacial transitions

Looy and her team also will look at an even earlier transition from a glaciated Earth 130,000 years ago to a time 113,000 years ago when it may have been locally warmer than today. Learning what the area looked like during that time will help Northern Californians anticipate how conditions will change as global temperature continues to rise over the coming decades.

“There are indications from ice cores and ocean drilling cores that the beginning of the previous interglacial may have been warmer than it is now, which is where it becomes interesting,” said Looy. “We know what the Earth is like at today’s temperature, but a lot of people are trying to predict what will happen if the earth warms 1 or 2 degrees Celsius (2-4 degrees Fahrenheit), or even more.”

Charcoal in the lake sediments will also tell the researchers how Native Americans altered the environment through deliberate fires designed, for example, to increase acorn production by oaks.

One member of the team, Anthony Barnosky, UC Berkeley professor of integrative biology, will correlate this information with mammalian fossils collected from cave deposits in the area and that have been stored for decades in the Museum of Paleontology.

“You can view the core as a time machine by which we can define a continuous record of change, both climatic and vegetational, though the past 130,000 years, and then we have all these floating snapshots of the ecosystem – the mammal communities – from cave deposits around here,” Barnosky said. “We can put names on these fossils and radiocarbon-date them and begin to build a 3-D picture of change through time from the late Pleistocene, some 130,000 years ago, through the last glacial/interglacial transition 13,000 to 11,000 years ago, all the way up to the present.”

The study will help to evaluate and refine current models that predict how plants and animals will adapt to a changing world by testing predictions of the models against what actually happened during past times of climate change. Such models are important for state and local planning agencies that must deal with future consequences of climate change, including sea level rise, water shortages and increasing fire incidence that can threaten ecosystems.

“Based on this type of research at UC Berkeley, we want to make the case that adaptation to a changing climate is an issue we have to take more seriously, we have to bring it more into the mainstream of Bay Area planning,” said Bruce Riordan, director of the Bay Area Joint Policy Committee, which coordinates regional planning agencies in responding to climate adaptation. “By starting planning now and understanding the problems, the strategies we need to implement and the costs involved, we may find less costly solutions today rather than later. The research can really help inform about both the problems and about the solutions.”

Half million years of sediment

Clear Lake is unusual in having survived the advance and retreat of glaciers that scoured and obliterated most lakes outside the tropics, including the large lakes in California’s Sierra Nevada. Previous coring in Clear Lake by the U.S. Geological Survey (USGS) in 1973 and 1980 revealed lake sediments half a million years old, with only three breaks in continuity. At the site where UC Berkeley plans to obtain cores, in the upper arm of the lake about 1-3 miles west southwest of the town of Lucerne, the USGS obtained a continuous core in 1973 going back 130,000 years.

Looy and her team hired Utah-based DOSECC (Drilling, Observation and Sampling of the Earths Continental Crust), a non-profit scientific drilling company, to obtain two 120 meter-long (400-foot) cores, each about 8 centimeters (3 inches) in diameter. The cores are obtained in 3-meter (10-foot) chunks that are capped and labeled at the site and will be shipped to a cold-storage facility in Minnesota operated by LacCore (National Lacustrine Core Facility), a non-profit organization funded by the National Science Foundation and the University of Minnesota. In the facility’s cold lab, the team will split each chunk longitudinally, photograph the halves, and then bring one half of each chunk back to UC Berkeley for analysis.

While the USGS sampled its cores once every meter, Looy and her team will sample parts of their cores every centimeter, the equivalent of about 10 years of sediment.

“We will get 100 times better time resolution, and can follow what happens when you rapidly warm the Earth up,” Looy said.

“The detail we can get from Clear Lake is really impressive,” she added. “The material is well preserved, and the USGS did a great job in describing the whole time interval so that now we know what the interesting areas are to focus on. We know this is not a shot in the dark.”

The Clear Lake drilling project is one of seven research projects involving global change forecasting funded by a $2.5 million grant from the Gordon and Betty Moore Foundation to UC Berkeley’s Berkeley Initiative in Global Change Biology, or BiGCB. Each project focuses on a particular California environment and leverages UC Berkeley’s unique museum collections of vertebrates, insects, plants and fossils to provide details about past changes in plant and animal populations.

Related information:

• Berkeley Initiative in Global Change Biology
• Cindy Looy’s Web site
• Tony Barnosky’s Web site

so

The Younger Dryas Impact Hypothesis Revisited

Update 3/16/2012:

Since I’ve been talking about Cluster Airburst events since I started this little amateur blog back in 2009, and in light of recent developments in the Younger Dryas Impact Hypothesis, I think it’s time for this humble amateur take this opportunity to write an update.

Last year when I wrote A Different Kind of Climate catastrophe I pointed out that one of the major flaws in the YD impact hypothesis as written in the original 2007 paper was that Firestone et al weren’t working from a valid astronomical model. In fact, they were all over the place with their speculation as to just what the nature of the catastrophe 12,900 years ago may have been, or what had hit us. That’s what got them into trouble and gave opponents to the hypothesis the rallying cry of “Where’s the crater?” But to be fair, they were citing the work of Toon et al in their estimate that it would take a four mile wide bolide to account for a continent wide debris layer. And at the time, Toon et al’s work on impact scaling was respected as the state of the science in the impact research community.

The physicist who came out as the chief skeptic of the hypothesis, Mark Boslough, and who correctly pointed out that it is physically impossible for a four mile wide bolide to have enough time in the atmosphere to break up completely and scatter fragments, and debris, over a continent sized area without making a good sized crater somewhere just happens to be the same scientist who first considered that very large airburst phenomena might be capable of significant melting, and efficient ablation the surface of the Earth without making a crater.

Since 2007 the YD Impact hypothesis has come under fire from numerous skeptics. And it finds a current update, and a new iteration in the work of Isabel Israde-Alcántara et al in their March 2012 paper published in PNAS and titled Evidence from central Mexico supporting the Younger Dryas extraterrestrial impact hypothesis

All of the arguments of the skeptics to date have been addressed in this new version. But more importantly for my own work here is that everything I have been saying about the potential for cluster airburst events, airburst phenomena and the fact that the hypothesis should be updated to be in line with Clube & Napier’s work on the Taurid complex is supported in this new paper.

As of this date though, I think I remain the only researcher who contends that very large airbursts have produced significant ablative geomorphology in the geologically recent past. And that the YD event did indeed produce significant planetary scarring. It just wasn’t anything that anyone has ever imagined as possible in an impact event.

I immediately seized upon the work of W.M. Napier in 2010 when I cited his paper titled Paleolithic extinctions and the Taurid Complex here in this article in my own amateur expression of the hypothesis, and my description of what I interpret as some of the planetary scarring of the event. And now it’s official: The Taurid Complex is the stated astronomical model for the event.

from Evidence from central Mexico supporting the Younger Dryas extraterrestrial impact hypothesis:

Comets.

Based upon astrophysical observations and modeling,
Napier proposed that YDB impact markers were produced when Earth encountered a dense trail of material from a large already fragmented comet. His model predicts cluster airbursts and/or small cratering impacts that could account for the wide distribution of YD impact debris across more than 10% of the planet, including Cuitzeo. Most comets eventually break up as they transit the inner solar system, and previously unknown fragmented comets are discovered by space-borne telescopes, such as the Solar and Heliospheric Observatory, on average every 4 y. As evidence, Earth is bombarded at an average rate of once every 5 d by one of 72 meteor streams or “showers,” massive clouds of debris from fragmented comets. These well-known meteor showers, e.g., Perseids, Geminids, Taurids, etc., are highly dispersed, but in the recent geologic past, each stream was far more condensed, containing many large, potentially destructive fragments. Currently, the Taurid Complex contains 19 large near-earth Apollo asteroids, with diameters ranging from approximately 1.5 km to approximately 5 km. None of these currently threatens Earth but may do so in the future

Impact research is an infant science. And thanks to poor funding for Near Earth Object research, and for impact science in general, we don’t have a very good handle yet on the variety or quantity, of objects out there that might threaten our world, much less a comfortable understanding of the different kinds of devastation that might be released in a catastrophic impact besides what we see in a generic, single, solid-bolide, crater forming, kinetic impact event. But in light of the new data published in this new paper I think it’s time to realize that craters are not the only kind of planetary scarring we can expect in an impact event. And this new work clearly recognizes that single lone bolides, are not the only kind of catastrophic impact event we can expect in the future.

The radical part that the impact community is having a hard time considering is the idea that thousands of small impacts can happen in a single cluster impact event.

And since it has been assumed without question for more than 150 years that the only possible source of enough heat, and pressure to melt the surface of the Earth is terrestrial volcanism, the very idea that a very large aerial burst might be capable of efficient melting, and ablation, of surface rock without making a crater is especially difficult for planetary scientists to accept because it implies that there may be significant planetary scarring from ablative airburst events in the past that has been misdefined as volcanogenic.

Also, the consensus view held by NASA, and most mainstream planetary scientists is that impacts happen at a slow, and predictable rate, one at a time. And that you can therefore estimate the age of a planetary surface by counting the number of craters in any given surface. But the simple unassailable fact is that as W. M. Napier pointed out in his 2010 paper titled Palaeolithic extinctions and the Taurid Complex large clusters of small cometary fragments do indeed exist in short period Earth-crossing orbits that also cross the orbits of all the planets of the inner solar system. In fact they’re fairly common; as these images of comets Linear, and SW-3 can attest.

The problem for mainstream planetary scientists is that if they acknowledge that such large clusters of small fragments really do hit the planets of the inner solar system from time to time. Then decades of work estimating the age of surfaces on the Moon, Mars, and every other rocky body in the inner solar system by counting the number of craters goes right out the window.

Holes in New Mexico, and the Craters On Mars

 

In Many of my previous posts I’ve focused a lot of attention on some of the “enigmatic depressions” in New Mexico. And there seems to be a strong resistance to the idea that they could actually be impact structures. The most common assumption I hear is that since there are so many of them, they must be all sinkholes.

But as I pointed out in the post titled Sinkholes n Craters, since all material movement in the formation of a karst sinkhole is downwards, there is nothing at all in that process that could account for raised  rims between two overlapping sinkholes. And we can clearly see raised rims between craters in the image below.

Here’s a few more examples:

		Craters VIEW SLIDE SHOW DOWNLOAD ALL

Another common argument I’ve heard is that they don’t look anything like the morphology of a crater; citing the lack of obvious ejecta. I don’t know how long those folks would expect any ejecta from an impact event to survive undisturbed under the influence of the wind, and rain. But let’s look at some certifiable impact structures on mars.

Below is a hi resolution image of a fairly small location inside Gusev crater on Mars. The landing site of the Spirit rover is circled in the bottom left of the image. And if you click on the image for an enlarged view, you can make out the three petals of the landing platform the rover drove off of after landing. The largest crater in the image is Bonneville crater. It is 210 meters in diameter, 14 meters deep and its rim rises 6.4 meters above the surrounding terrain.

It does not rain there, but the wind blows. And as you can see, even with the very high resolution, there is also no obvious expression of the ejecta from any of those craters either.

I hope you’ll take your time. And closely compare the images of terrains in New Mexico with this image of the surface of Mars.

The standard assumption has always been that all impact events, great, or small, must be the result of the impact of a single lone bolide. And part and parcel with that assumption is that they rain down on any given surface in the solar system at a slow, and steady, rate.

So the consensus among planetary scientists is that one can therefore estimate the age of a planetary surface by counting the number of craters. The fewer the craters in any given surface, the younger that surface is thought to be.

But while there is nothing in the images of Mars, or the Moon, that might bring the assumption of a steady impact rate into question, from a forensic perspective those in new Mexico describe a different kind of catastrophic impact event. They all appear in surfaces that can be dated to the Late Pleistocene or Early Holocene. And they describe the almost simultaneous impact of a large cluster of small fragments sometime around the end of the last ice age. Or right about the time something caused the mass extinction of most of the megafauna in North America. And triggered a return to Ice age conditions that lasted something like 1,300 years.

Astronomer W.M. Napier proposed just such an event in his 2010 paper titled Palaeolithic extinctions and the Taurid Complex. In that paper Professor Napier points out that the breakup of comets is now a well recognized path to their destruction.

And if if you are wondering how hard clusters of fragments like I’ve described are to be found in the celestial zoo, it doesn’t take much time to find them. They’re really fairly common.

As a matter of fact take a look at a Hubble Telescope image of the fragments of Comet Linear.

 

Or the fragments of comet Swchassmann Wachmann 3

The simple fact is that clusters of comet fragments orbiting in the plane of the ecliptic, and in elliptical orbits that cross the orbits of all the inner planets are very common. Therefore cluster impact events must be far more common than has been assumed in the past.

And all it would take is one impact by a cluster of comet fragments like we see above to make NASAs unquestioned assumption that you can estimate the age of a planetary surface by counting the number of craters, and all of the studies based on that assumption meaningless.

The Sierra Madera Cryptoexplosion Structure

In 1972 H. G. Wilshire et al published a paper for NASA titled . Geology of the Sierra Madera Cryptoexplosion Structure, Pecos County, Texas.

  
One of the major problems with getting a good handle on the impact record of the past is in the naïve assumption that round craters from the direct kinetic impact of a solid object hitting the ground are the only possible planetary scarring we should expect to find.

We are only now beginning to realize that very large airbursts might be capable of significant geologic change. And that the planetary scarring of such an event will have no resemblance whatsoever to an impact crater.

Wilshire et al didn’t have access to high resolution satellite imagery. If they had, they might have noticed that it is a close match for some structures just across the border in North Central Mexico, and that are in almost perfectly pristine condition.

See ‘A Thermal Airburst Impact Structure’  or Airburst Scar

Folks might note that the patterns of motion in the emplacement of the blast-effected materials at the Sierra Madera cryptoexplosion structure, and the numerous pristine examples like it across the border that are in even better condition, i.e. radial outwards at the periphery, and inwards and upwards, at the center, are a perfect match for the bottom of an ablative airburst vortex such as the ones depicted in Mark Boslough’s supercomputer simulations.

In 1972 Wilshire et al could never have imagined that an airburst such as the Tunguska event of 1908  could be large enough to produce significant geologic change. And since the only models for an impact structure they could imagine were the craters we see on the moon and Mars, they assumed without question that it was caused by the impact of a solid object. And they explained the lack of a crater rim by proposing that the explosive event happened in the Late Cretaceous or early Tertiary. And that the crater rim has eroded away in the millions of years since.

But using high resolution satellite imagery, a careful study of the radial patterns of flow in the emplacement of the fluidized flows of breccias and clastic materials surrounding the central uplift of it, and others like it across the border in Mexico will reveal that the structure is in almost pristine condition, and that it was never a crater with a rim.

The entire region is imaged to a resolution of better than 1 meter per pixel in Google Earth; good enough to count the number of cattle a rancher has on his place. And good enough to recognize and read the directionality of emplacement in pyroclastic materials on the surface like following spilled paint back to the can. If the structure were as old as Wilshire et al thought, the patterns of fluid motion in the flows of pyroclastic material at Sierra Madera, and places like it across the border would’ve been erased millions of years ago along with any ring structures. Yet those radial flows of breccias, and pyroclastic material surrounding the central uplifts are virtually undisturbed, and on the surface; a fact that argues for a much younger age for the explosive events that put them there.

Wilshire et al didn’t use any radiometric data. And in 1972 they were still working from the assumption that all impact structures are the result of the impact of a solid object. They couldn’t have imagined that an airburst might be capable of significant geologic change. So their estimate of great age is based on the assumption that enough time has passed to erode away a crater rim. There is no mention of isotopic analysis of specimens from there. But it would be interesting to take a piece of rock that was melted in one of those events, check for ET isotopes, and try to get a definitive age since melt from it.

Once you recognize the real nature of the above ground explosive event that formed the Sierra Madera structure, and its sisters across the border, you also come to the realization that the blast-effected materials of the event, i.e. the radial outwards flowing emplacements of  fluidized flows of pyroclastic rock, and breccias, surrounding a central uplift of shatter cones, and blast effects pointing inwards, and upwards, are not the result of a sold object hitting the ground. And that fact forces the conclusion that, contrary to the uniformitarian/gradualist assumptive theory for the mechanics if its formation as expressed by Wilson et al, There never was a crater rim to erode away. The ground at Sierra Madera wasn’t heavily eroded over millions of years, it was heavily ablated over a period of just a few seconds in a large, ablative airburst event.  The condition of the blast-effected materials of that above-ground explosion are, in fact, almost perfectly pristine, and they remain virtually undisturbed on the surface since the explosion that put them there. Whatever else the Sierra Madera structure is, geologically old it isn’t.

Did the Earth dodge a bullet in 1883?

I’ve been talking about the danger posed by fragmented comets for a couple of years now. Here’s a scary article that is supportive of that view. From MIT’s Technology Review we read:

Billion Tonne Comet May Have Missed Earth By A Few Hundred Kilometers in 1883

A re-analysis of historical observations suggest Earth narrowly avoided an extinction event just over a hundred years ago.

kfc 10/17/2011

The fragments of  Comet Scwassmann-Wachmann 3

The fragments of Comet Linear

On 12th and 13th August 1883, an astronomer at a small observatory in Zacatecas in Mexico made an extraordinary observation. José Bonilla counted some 450 objects, each surrounded by a kind of mist, passing across the face of the Sun.

Bonilla published his account of this event in a French journal called L’Astronomie in 1886. Unable to account for the phenomenon, the editor of the journal suggested, rather incredulously, that it must have been caused by birds, insects or dust passing front of the Bonilla’s telescope. (Since then, others have adopted Bonilla’s observations as the first evidence of UFOs.)

Today, Hector Manterola at the National Autonomous University of Mexico in Mexico City, and a couple of pals, give a different interpretation. They think that Bonilla must have been seeing fragments of a comet that had recently broken up. This explains the ‘misty’ appearance of the pieces and why they were so close together.

But there’s much more that Manterola and co have deduced. They point out that nobody else on the planet seems to have seen this comet passing in front of the Sun, even though the nearest observatories in those days were just a few hundred kilometres away.

That can be explained using parallax. If the fragments were close to Earth, parallax would have ensured that they would not have been in line with the Sun even for observers nearby. And since Mexico is at the same latitude as the Sahara, northern India and south-east Asia, it’s not hard to imagine that nobody else was looking.

Manterola and pals have used this to place limits on how close the fragments must have been: between 600 km and 8000 km of Earth. That’s just a hair’s breadth.

What’s more, Manterola and co estimate that these objects must have ranged in size from 50 to 800 metres across and that the parent comet must originally have tipped the scales at a billion tonnes or more, that’s huge, approaching the size of Halley’s comet.

That’s an eye opening re-examination of the data. Astronomers have seen a number of other comets fragment. The image above shows the Schwassmann-Wachmann 3 comet which broke apart as it re-entered the inner Solar System in 2006. There’s no reason why such fragments couldn’t pass close by Earth.

One puzzle is why nobody else saw this comet. It must have been particularly dull to have escaped observation before and after its close approach. However, Manterola and co suggest that it may have been a comet called Pons-Brooks seen that same year by American astronomers.

Manterola and co end their paper by spelling out just how close Earth may have come to catastrophe that day. They point out that Bonilla observed these objects for about three and a half hours over two days. This implies an average of 131 objects per hour and a total of 3275 objects in the time between observations.

Each fragment was at least as big as the one thought to have hit Tunguska. Manterola and co end with this: "So if they had collided with Earth we would have had 3275 Tunguska events in two days, probably an extinction event."

A sobering thought.

Ref: arxiv.org/abs/1110.2798: Interpretation Of The Observations Made In 1883 In Zacatecas (Mexico): A Fragmented Comet That Nearly Hits The Earth

Sinkholes ‘n’ Craters

I’ve been going on about some enigmatic, circular, depressions in New Mexico for a few months now. The consensus among those who are skeptical of impact events is that they are all related to karst geology. And that they are  all just sinkholes. Many of them are probably just that.

I found a new sinkhole at 32.731966, -104.127823 that would seem to be supportive of that view. It’s in an oil field. And a quick check of the location with Google Earth’s historical image feature reveals that it wasn’t there in 2005.  It is almost certainly the result of a water injection well gone wrong. So we can say it’s man-made.

It’s a common cliché that the best place to hide a tree is in a forest. Likewise, the best place to hide a field of small craters is in limestone. No self respecting uniformitarian conditioned geologist would look twice at the thousands of circular depressions in New Mexico.

However, this man-made, but certifiable, sinkhole can be used as a standard example of the morphology of a true sinkhole that others in the state can be compared to.

The injection well created a cavern by dissolving  a void deep in the limestone below. Once enough limestone was dissolved, and removed, the the rock was no longer strong enough to support the weight above. And the surface collapsed into the resulting cave, forming a classic sinkhole.

The water from the injection well accelerated the rate at which the limestone dissolved. And the resulting cave would have grown at hundreds of times the erosion rate expected by normal ground water flow. But the collapse itself, and  resulting sinkhole, were nevertheless a perfectly natural karst collapse. Making it a good standard model of a sinkhole.

And since all material movement was downwards, there is nothing in the process that formed that sinkhole that could account for raised rims, or overlapping craters with raised rims between them. Nor is there anything in the process we see there that could account for materials thrown outside the hole.

Take a close look at the area shown in the image below. Note the raised  rims. Especially between some of the ones that overlap. I won’t speak for others. But as for me, I remain convinced that these things are a field of small impact craters.

Holes in the ground

From Wikipedia we read that ‘Crater’ may refer to:

In landforms:

• Impact crater, caused by two celestial bodies impacting each other, such as a meteorite hitting a planet
• Volcanic crater or caldera, formed by volcanic activity
• Subsidence crater, from an underground (usually nuclear) explosion
• A maar crater, a relief crater caused by a phreatic eruption or explosion
• pit crater, a crater that forms through sinking of the surface and not as a vent for lava
• Crater lake
• Explosion crater, a hole formed in the ground produced by an explosion near or below the surface.

Here we see a small Crater field on Mars. The largest of the small craters you see here is about 500 meters across. The consensus is that they are all impact craters. The problems we have here is in the uniform condition of the craters, and their sizes, and distribution.

If, as is assumed, impact events do indeed happen at a steady rate, and these impacts all happened one at a time, over a long period, then we should see some variation of condition from the earliest, to the most recent. Also, they are concentrated into fields of craters surrounded by large areas with no craters at all. If they fell one at a time, then they should be evenly distributed all over entire the surface of the planet.  They could only be in a concentrated cluster like this, in exactly the same condition, if they all fell at the same time, in a meteoroid swarm.

On Mars, it is assumed without question that we are looking at impact craters. But here on Earth, if we see the same fractal distribution of craters, the tendency is to deny that so many impact craters could happen in a terrestrial surface; much less that a large cluster of small fragments could hit all at the same time.

Our astronomers tell us that a meteoroid swarm of small fragments is a more probable event, than a large, solid bolide. Yet most geologists agree that such things cannot be…. At least, not here on Earth.

But we are orbiting around in the very same shooting gallery as Mars. And in central, and eastern, New Mexico, there are thousands of  small craters. All in the very same geologic condition. They are a bit small compared to the ones we see above. But the New Mexico craters have exactly the same fractal distribution as some of the crater fields on Mars. And except for differences in weathering that can be accounted for by different atmospheric conditions, they are in the very same geologic condition.

View Full Album

If those in New Mexico didn’t form by impact there is no reason to assume those in the images from Mars did either.

Until we’ve been there on the ground.

More New Mexico Craters

Much of the academic community assume that a typical catastrophic impact event consists of a single, large bolide. When asked what he thought of the possibility of a cluster impact event of smaller fragments, NASA’s David Morrison expressed doubt. He said he thought such an event would be “highly unlikely”. And since he’s the senior scientist at the NASA Ames Research Center, his views are representative of mainstream planetary science.

But ongoing inventories of the objects orbiting in the Taurid complex are bringing data to light that indicates that, in fact, the last extinction level impact event in the northern hemisphere was probably the work of a very large cluster of debris from a large disintegrating comet, not the kinetic impact of a single, solid bolide.

And in a 2009 paper by W.M. Napier, and titled Comets, Catastrophes, and Earth’s History we read ,

“The evidence that an exceptionally large (50-100 km) comet entered a short-period, Earth- crossing orbit during the upper Paleolithic, and underwent a series of disintegrations, now seems compelling. The idea is not new, but it has been strengthened by an accumulation of evidence from radar studies of the interplanetary environment, from the LDEF experiment, from numerical simulations of the Taurid complex meteoroids and ‘asteroids’, and from the latter’s highly significant orbital clustering around Comet Encke.

The disintegration of this massive Taurid Complex progenitor over some tens of thousands of years would yield meteoroid swarms which could easily lead to brief, catastrophic episodes of multiple bombardment by sub-kilometer bolides, and it is tempting to see the event at ~12,900 BP as an instance of this. Whether it actually happened is a matter for Earth scientists, but from the astronomical point of view a meteoroid swarm is a much more probable event than a 4 km comet collision.”

If Professor Napier is correct, we should expect to find the planetary scarring of a geologically recent super cluster impact event of smaller fragments somewhere in North America.

And in the world according to Google Earth, that planetary scarring does indeed exist. And a good case can be made that New Mexico, and West Texas, were a couple of the major impact zones. But in spite of posting pictures of these ‘enigmatic depressions’ for a couple of years now, none of the mainstream scientists I’ve written to seems to be interested in talking about them. And I haven’t been able to find evidence that anyone has done any real science at any of them either.

I struggle with the mystery of how they can be so dramatically obvious in satellite imagery, and yet,  no one has gotten curious about them.

Their existence plays hell with the idea that we can estimate the age of a planetary surface by the number of craters we can see in a satellite image.

Even if they can be proven to have formed by something besides an impact event, we still have a problem. In satellite images they are visually indistinguishable from impact craters. If such geologic features can be shown to have a non-impact origin here on Earth, then what does that say for the very same geomorphology elsewhere in the solar system? Or the idea that you can estimate the age of a planetary surface by counting them?

Which would have the most profound effect on planetary science?

A series of  large crater fields in North America describing the simultaneous impacts of thousands of small comet fragments, with thousands of sports stadium sized craters all the same late Pleistocene age?

Or proof that there is an active geologic process at work in the solar system that can produce thousands of circular depressions with raised rims, that are visually identical to impact craters?

If they are indeed impact craters, then they have a very profound effect on impact threat assessment. And they represent the cusp of a major paradigm shift in impact research. As we move away from thinking of a catastrophic impact event as being the result of the kinetic impact of a single solid body,  to thinking of multiple fragment impact storms of mostly air-bursting smaller fragments.

Are they only sinkholes? Personally, I doubt it. Because if they are, and if any given sinkhole is only part of a larger cave system beneath, then they represent the surface manifestations of a giant, interconnected, cave system stretching across two states, and covering tens of thousands of square miles. It would have be the largest known cave system on Earth. And again, they are visually indistinguishable from impact craters.

If they weren’t formed by impact, then we can no longer assume that identical looking geologic features on the moon, and Mars, were formed by impact either, until we have been there ‘on the ground’.

No one’s talking about them yet. But that doesn’t mean I can’t keep pointing at them.

Here’s a few more.

The map coordinates, view height, and scale, are in the info bar at the bottom of each image.

If you’d like to see more, I’ve put a few other places in a photo gallery called Crater Field

Re-stating a question

In my earlier posts , If not by impact, then what?,  A few craters more, and The Meteorite Men, and The Odessa Crater, I wrote of the numerous small craters in New Mexico, and west Texas. And the question remains essentially unanswered.

Since none of them have been officially confirmed as impact structures, we’ll just call them ‘enigmatic depressions’ for now. I’ve received quite a few emails from folks about what they thought happened to form them.  And they proposed every thing from inter-planetary electric discharges, to karst collapses, and oil field blowouts.

But missing from the responses so far, is an answer from a trained geologist, or impact scientist. And in spite of the fact that they are dramatically obvious in satellite image data, I haven’t been able to turn up anything online, or in the literature, that indicates anyone has done any real science at any of them. Although with my limited access to the literature, that may simply be because I haven’t looked in the right places.

I’d like to reiterate the question. But this time I’m hopping to hear a plausible, well thought out, theory from a trained Geologist that describes a  non-impact related process for their formation. And if possible, I hope someone can tell me of some honest science that’s been done on them.

They are all in the very same geologic condition. Indicating that they are all close to the same age. And they predominate in surfaces, and terrains, that date to the late Pleistocene.

If they are indeed impact craters, then their very existence, and in such numbers, has a profound effect on impact threat assessment. Because that would mean that impact events that consist of large clusters of smaller fragments do indeed happen. And that they have done so in the geologically recent past.  It also means that the ideas that we can assume a steady, and consistent, flux of impacts in the solar system, and that we can estimate the age of a planetary surface by counting the number of craters in any given area become almost childishly naïve.

If they weren’t formed in an impact event, they are none the less significant, and exiting. Because in that case, they demonstrate empirically that there is a geologic process in the solar system that can produce structures which, when viewed in satellite imagery, are visually indistinguishable from impact craters.

And again, the idea that you can estimate the age of a planetary surface by counting the number of craters visible in a satellite image falls apart.

If they’re all karst collapses, and if any given sinkhole is only part of much larger cave system beneath, then we are looking at the upper surface of a vast, inter-connecting, cave system extending over tens of thousands of square miles. And that would make it the largest known cave system in the solar system. Still an amazing, and paradigm shifting, result.

So, again, if those things weren’t formed by impact, then what?

Study the image below closely. Note the over lapping rims in some of them. Overlapping karst sinkholes don’t have raised rims. But overlapping impact craters do.

The image below is the same place in late summer. The red line is 100 meters for scale.

The shear numbers become apparent when you zoom out to about 6 km.

 

If not by impact, then what?

One of the large regions that tweaks my curiosity about impact events in a very big way is an area that extends from eastern New Mexico to just the other side of Odessa, and Midland, Texas.

In the image below we see a small part of that area near Vaughn, New Mexico. Using Google Earth’s historical image feature, we can view the same place from about 15,000 feet, in images taken at different times of the year.          .

As you can see, there are numerous craters. You get a different set of colors in the late summer.

The early black & white images are sometimes even more telling.

These next few are little closer to Vaughn.

Here it is in the late summer.

And in black& white.

Crater fields of comparable fragment sizes can be found in scattered, locally dense, clusters all the way to central Texas.

Anyone can Google up some images of the Odessa crater, in west Texas. But the big mystery I’m struggling with is, what about all the others? In the world according to Google Earth, the Odessa crater is only one of thousands liberally scattered among the oil fields of west Texas. In the image you see below, the white lines are dirt roads about 7, or 8, meters wide. And each of the clearings that show up as little rectangles of a half an acre, or so, are the location of an oil well pump.

 

Let’s zoom in close to one of the craters. This one’s almost 190 meters wide.

The early black & white view is interesting too.

This one’s interesting too. Three at a time.

And a classic double ring crater.

On any other planetary surface in the solar system no one would hesitate to trust their eyes, and call these these what they look like; impact craters.

I asked NASA’s David Morrison what he thought of these things. He expressed his doubts. He said he thought that a cluster impact event would be “Highly unlikely”.  And his views are typical of most mainstream planetary scientists.

But in march 2010, W. M. Napier  published  a paper in the Journal Monthly Notices of the Royal Astronomical Society, and titled, Paleolithic extinctions and the Taurid Complex. In it professor Napier points out that:

“The fragmentation of comets is now recognized as a major route of their disintegration, and this is consistent with the numerous sub-streams and co-moving observed in the Taurid complex.”

And in an earlier 2009 paper by professor Napier, and titled Comets, Catastrophes, and Earth’s History we read ,

“The evidence that an exceptionally large (50-100 km) comet entered a short-period, Earth- crossing orbit during the upper Paleolithic, and underwent a series of disintegrations, now seems compelling. The idea is not new, but it has been strengthened by an accumulation of evidence from radar studies of the interplanetary environment, from the LDEF experiment, from numerical simulations of the Taurid complex meteoroids and ‘asteroids’, and from the latter’s highly significant orbital clustering around Comet Encke.

The disintegration of this massive Taurid Complex progenitor over some tens of thousands of years would yield meteoroid swarms which could easily lead to brief, catastrophic episodes of multiple bombardment by sub-kilometer bolides, and it is tempting to see the event at ∼ 12,900 BP as an instance of this. Whether it actually happened is a matter for Earth scientists, but from the astronomical point of view a meteoroid swarm is a much more probable event than a 4 km comet collision

Most of the academic community assume that large clusters of cometary debris don’t hit the Earth. At least, not in the geologically recent past. And when looking for answers, the typical response for those in New Mexico is that they are all probably karst sinkholes, because they are all in limestone.

But there’s just too darn many of them. Any given karst sinkhole is representative of a partial collapse of a much larger cave system beneath. And if we work from the gradualist postulate that these holes in the ground appeared, over a great span of time, our thinking is still stuck in a box.

There are many thousands of them, in many different terrains, and all in exactly the same almost pristine condition. They can be found in numerous large clusters, in a variety of sizes in a vast region that includes almost all of eastern New Mexico, and West Texas. And they average about 100 meters in diameter.  

Take your pick. Which is more plausible? A giant series of inter-connecting cave systems covering tens of thousands of square miles, with too many large sinkholes as big as a large sports  stadium, all breaking the surface, and collapsing, at nearly the same time to count? Or the giant crater fields caused by the almost simultaneous, late Pleistocene – early Holocene impacts of a cluster of cometary fragments from the Taurids?

I’ve been asking around, and digging  for evidence that someone has actually done some real science on these things. And all I’ve been able to get are wimpy answers that begin with; “Well, most geologists agree that______”, or words to that effect. Heck, I don’t care what they’ve all decided to agree about. I want to know what evidence they’ve dug up. Can someone tell me who has done some science there?

As for me, and until proven otherwise, I prefer to trust my own eyes. Those surfaces we see those things in all date to the late Pleistocene. And I’m working from the postulate that they are related to the impact storms of the Taurid progenitor.

There’s a few more to be seen in this gallery called Craterfield.