March 5, 2024 | David F. Coppedge

The Stuff Happens Law in Geology

“Then something happened,”
say geologists who weren’t there
and didn’t witness anything

 

If you thought the Stuff Happens Law worked only in evolutionary biology, the reality is far more broad. Every science that tries to explain the universe, the stars, the earth and life by natural processes depends on it.

Geologists explore the hidden history of Colorado’s Spanish Peaks (University of Colorado at Boulder, 4 March 2024). A pair of isolated mountains in southeast Colorado is an anomaly. However they arose, these so-called Spanish Peaks didn’t follow current theory of orogeny (mountain building). Geologists at the U of Colorado tried to figure out what happened. It was something.

According to the team’s results, the Spanish Peaks first formed when magma welled up from deep within Earth’s crust but didn’t quite break through to the surface.

Then, something happened. In a very short span of time, geologically-speaking, huge tracks [sic] of land in southeastern Colorado vanished. Between roughly 18 and 14 million years ago, more than a mile of sedimentary rocks around the Spanish Peaks eroded away, then were swept into the Arkansas River.

The researchers suspect that as-of-yet-unidentified geologic forces were pushing up southeastern Colorado from below—exposing previously underground rocks to rain and flowing water.

Did they see stuff happen? No. Did they travel in a time machine 18 million years back? No. Did they witness a mile of sedimentary rocks form? No. Did they see them vanish? No. Did they identify geological forces capable of doing these things? No. Are any such huge tracts of land vanishing into rivers today? No. But hey; stuff happens.

All they did was take samples at three sites and use voodoo dating on them, called U-Th/He Thermochronology. This divination method supposedly reveals to their imaginations how many million Darwin Years ago the rocks were hot. Their results were published open access in the GSA journal Lithosphere on March 1. With acronyms and Jargonwocky, they describe what they didn’t see happen.

The total thickness of any preexisting WRE [White River Equivalent] material that once overlaid the Spanish Peaks is unknown, so we cannot constrain the maximum burial depth of the pluton with confidence using just its stratigraphic position. However, based on the preceding arguments, a burial depth of 2 km would likely require a little over 1 km of now-eroded WRE material. Deeper emplacement depths, such as that modeled in online Supplementary Material Figure S3, would require abundantly thicker WRE sections. The High Plains generally lack accommodation space, making it unlikely that multiple kilometers of WRE ever accumulated there. When Cather et al. (2012) projected the gentle east dip of the Ogallala Formation from its westernmost outcrop on the Colorado High Plains near Limon (Figure 1) westward onto the RMES, they estimated that about 800 m of pre-Ogallala material has been eroded from beneath the basal Ogallala unconformity to the present land surface that consists of Cretaceous WIS sediments at the western limit of the High Plains [5]. Based on these considerations, we think it unlikely that more than 1–2 km of WRE sediments ever accumulated above the Spanish Peaks, hence our choice of a 1–2 km burial depth for the control sample LA19-9 in our favored HeFTy model (Figure 6). However, Cather et al.’s [5] analysis assumes that the Ogallala Formation once extended westward all the way to the Rockies, which our Apishapa Dikes data calls into question for SE Colorado, and in any case it applies only to post-Ogallala erosion; if a considerable thickness of strata was removed from the entire High Plains prior to deposition of the Ogallala Formation, that analysis would not serve to constrain the magnitude of WRE removal.

If more than a kilometer of material vanished without a trace, it sounds like something catastrophic happened over a wide region—not the nearby river. Floods happen; is that a cause for consideration?

The rocks didn’t speak with a unified voice about how old they are. The authors picked and chose dates they liked.

Five apatite analyses that are reported in Table 1 are excluded from data plots because they appear to be outliers. Two of these grains are older than the crystallization age of the unit, two others are anomalously old compared with the rest of the sample’s data distribution, and one is anomalously young compared to the rest of the grains in the sample. A bias to older dates can occur because some difficult-to-detect factors such as micro-inclusions and He implantation yield excess He.

Sometimes anomalies give the most important data. Readers might recall that ICR’s RATE team identified excess helium in a deep well that was “anomalously young” compared to consensus theories on how old the strata were in the well. Good scientists don’t just toss out anomalies.

The whole region is anomalous:

A variety of recent studies have offered models to explain why the High Plains are so anomalously high; all such models need to reconcile this fundamental discrepancy between the Cenozoic erosional histories of these two segments of the High Plains, which in other respects seem to be nearly identical.

It might have been… wait for it… climate change!

We favor exhumation induced by Oligo-Miocene surface uplift as the primary explanation for the kilometer-scale Miocene exhumation that we document on SE Colorado’s High Plains. However, alternative explanations for a cooling signal in our AHe data include geotherm relaxation or exhumation induced by climate change or drainage reorganization.

Here we see how scientists hide their ignorance in noun phrases. “Climate change” is one such catch-all category that lends itself to glittering generalities. “Drainage reorganization” is another. Dr Scientist, please tell us how the drainages get reorganized. Answer: by drainage reorganization. Oh, now we understand! Dr Scientist, do you know this?

Drainage reorganization is another hypothetical cause of exhumation. Our study area lies in the modern drainage basin of the Arkansas River; if a stream capture event in Oligo-Miocene time expanded the Arkansas drainage basin, the resulting increase in river discharge might explain the observed exhumation event. Several authors have suggested that the current Arkansas River captured its upper reaches, which flow south along the RGR (Figure 1) sometime during the Neogene [62, 63]. However, very little is currently known about whether or when a stream capture event took place. If the Arkansas drainage basin was affected by a Neogene capture event, its erosional signal should propagate upstream (i.e., from east to west) through time; the fact that the Apishapa Dikes AHe dates are younger than those farther west at the Spanish Peaks suggests that drainage reorganization is an unlikely explanation for our High Plains erosion signal.

OK, so toss that explanation out. Climate change can be tossed out, too. What else happened? Rock uplift: that explains how rocks are uplifted! Result: mountains!

The evidence that geotherm relaxation, climate change, and drainage reorganization cannot, by themselves, explain our data leads us to conclude that southeastern Colorado’s High Plains must have experienced rock uplift during the Oligo-Miocene (Table 1). If the amount of rock uplift during that episode exceeded the magnitude of erosion, the High Plains experienced surface uplift during that event.

One last possibility they call “mantle drip.” Did they see that happen? No. It’s the only possibility left after all the other bad explanations are eliminated.

Any model that proposes to explain the surface uplift of Colorado’s High Plains must explain the fact that over 3 km of material has been removed from southeastern Colorado since the latest Oligocene but considerably less erosion has occurred in the northeastern part of the state during that same time interval. Thermal effects associated with the ignimbrite flare-up and formation of the RGR can explain this dichotomy, but detachment of a mantle drip centered beneath southeastern Colorado better fits the pattern and spatial scale of the exhumation event.

Where did all the sediments come from? Why are those sediments filled with billions of dead things buried in rock layers laid down by water all over the earth? They didn’t address that. It just “accumulated above the Great Unconformity during the early-middle Paleozoic.” The basins filled in by sediment accumulation. Now you know. Stuff happens in strange ways.

Star dunes in a southern California desert (DFC)

Watcha Dune, Geologist?

Hidden ‘star’ sand dune mystery solved by ancient find (Aberystwyth University, 4 March 2024). “Star” sand dunes are ones where ridges come together to a peak, forming a star pattern or pyramid shape. These are seen forming today around the earth, and even on other bodies in the solar system. But strangely, geologists can’t find any in Deep Time. Why is that? Geologists at Aberystwyth went to Morocco to look for clues and took their divination tool with them.

The research reveals the oldest parts of the base of the Moroccan dune are 13,000 years old. However, the discovery that it had formed rapidly in the last thousand years surprised scientists who had thought larger dunes were far older.

Believed to be the tallest dunes on Earth – with one in the Badain Jaran Desert in China reaching 300 metres high – star dunes are also found elsewhere in the solar system, on Mars and on Saturn’s moon Titan.

Despite being common today, star dunes have almost never been found in the geological record. Their absence has bemused scientists as past deserts are a common part of the history of Earth, preserved in rocks deep underground.

They observed an existing star dune, not any in the geologic record. How does that solve the mystery?

“This research is really the case of the missing sand dune – it had been a mystery why we could not see them in the geological record. It’s only because of new technology that we can now start to uncover their secrets.

“These findings will probably surprise a lot of people as we can see how quickly this enormous dune formed, and that it is moving across the desert at about 50 cm a year. These fantastic star dunes are one of the natural wonders of the world.”

Just like in Darwinian biology, Stuff Happens at different rates at different times. The model required some radical time adjustments. No slow and gradual dune formation here! It’s more like punctuated equilibria in evolutionary biology:

The scientists’ breakthrough research suggests the star dune formed at around the same time as the Younger Dryas event, an abrupt cooling period in Earth’s history. It also reveals that the dune stopped growing for a period of 8,000 years.

Pottery found at the site also suggests wetter conditions, perhaps an enlarged monsoon, that stabilised the dune before the onset of a great drought.

The study used luminescence dating techniques developed at Aberystwyth University to discover the last time minerals in the sand were exposed to sunlight to determine their age.

They are proud of their homegrown divination method, but have to live with a strange notion that a dune formed very rapidly, and then stopped for 8,000 years. That’s a pretty long drought for a planet whose weather is constantly changing.

They never got back to why star dunes are not found in the geological record. Does their paper in Science Advances help? No; they just explain it away as something that’s hard to identify, but they have some futureware to sell.

Individual sedimentary structures in star dunes are similar to those in linear or barchanoid dunes, likely leading to misidentification in the rock record. However, the suite of features described in this paper will permit identification of star dunes in future studies of the rock record. Optically stimulated luminescence (OSL) dating shows that accumulation of the Erg Chebbi star dune post-dates the end of the African Humid Period (AHP). At the base of the dune, there is an ~ 8000-year hiatus in the record. Since then, the dune has grown rapidly to create a 100 m high dune within the past 1000 years and is migrating towards the west. Changes in the cross-strata support the idea that star dune construction was accompanied by a change in the wind directions.

Is this plausible? Their deep-time narrative goes like this: A long time ago, a big erg (sand field) with a star dune forms in Morocco. Then nothing happens for 8,000 years. Then the wind shifts. A world record star dune piles up within centuries, and it’s moving. Yes, stuff happens in strange ways.

Are you bemused like these geologists? (bemused: bewildered, confused, lost in thought, preoccupied). No need to be. Read Genesis 1-12 to see what happened.

 

 

 

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