Monday, January 30, 2012

The Green River Formation varves

The great American southwest contains a wealth of geological evidence which can and should be examined to provide points of comparison between various geological paradigms.

A paradigm is an over-arching model or vision which ties together to provide a framework within which its proponents fit the various pieces of evidence that they encounter. Often, proponents of one paradigm are extremely resistant to suggestions that their entire framework for understanding the data could be wrong.

During the twentieth century, for example, the "fixists" who opposed the suggestions of Alfred Wegener regarding continental drift and plate tectonics were bitterly opposed to his new paradigm. They had a mental framework within which they could and did fit any piece of evidence that was presented to them, and from which they could and did criticize any alternative vision of how all that evidence could fit together.

Of course, it looks like they were completely wrong, as most conventional geologists today will agree.

Similarly, the geological evidence can be explained very differently by those who subscribe to different paradigms. Those who subscribe to the conventional geological paradigm that is dominant today try to fit all of the evidence surrounding the Grand Canyon into their mental framework, which involves millions of years of fairly uniform erosion by the Colorado River. They reject suggestions that this explanation could be completely wrong and that the evidence in the Grand Canyon and surrounding terrain could be better explained by catastrophic forces acting over a period of only weeks or months.

The Grand Canyon is just one example of geology in the American southwest that provides an outstanding laboratory for the comparison of different paradigms. Another is the famous Green River Formation, an extensive geological region located in what are now the United States (specifically, spanning terrain in present-day Wyoming, Utah, and Colorado).

Fossil Butte National Monument was established in 1972 to preserve a large portion of this fossil-rich geology. This webpage from the National Park Service explains that the current consensus of geologists is that the Green Mountain Formation is the product of "a sub-tropical lake ecosystem commonly referred to today as the 'Green River Lake System.'"

Under the conventional paradigm for explaining the evidence found in this region, geologists conclude that the layered sedimentary rock that makes up the formation today formed by the process of annual deposits over a period of at least two million years and possibly as many as six million years.

One of the main reasons for this conclusion is the presence of "varves" in the Green River formation (sometimes called laminae to distinguish them from varve layers thought to have been laid down by glaciers). Varves are thin layers of sedimentary particles which are sorted into alternating types of particle. In the Green River Formation, alternating layers of light and dark sediments are generally believed to represent alternating seasons of winter (less organic matter and therefore lighter coloration) and spring-summer (growing season, with more organic matter and therefore darker coloration). The fame of the Green River Formation stems from its record of more intact layers than perhaps anywhere else that we know of: six million unbroken layers of varves at some points!

Defenders of the conventional paradigm believe that the Green River Formation is one of their strongest arguments against theories involving catastrophic forces, and one of their strongest arguments for the acceptance of uniformitarian processes as the best explanation for the geological evidence that we find in the world around us.

For example, here is a webpage at the University of Indiana website in which teachers are provided with "talking points" to shut down any pesky students who "maintain that the varves are not annual, and/or the sediments were deposited during the great worldwide Noah's flood." There is a nice photograph of a portion of the Green River Formation at the bottom of that webpage, and teachers are encouraged to:
show this photo to your class, so they can actually see about 300 meters (~1,000 feet) of ancient lake sediments in the nearest cliffs, deposited over about 2 million years. Note the many more layers rising higher in the distance. You may want to point out that 7,000 years would create only about 1 meter (3 feet) of sediments, about the height of the cows across the river!
This approach, declaring that the evidence can only be explained under one paradigm and specifically marginalizing and ridiculing anyone who proposes alternate explanations, is unfortunate and unscientific. It is exactly reminiscent of the approach of the "fixists" who opposed Wegener during his life. It would be far better (and more scientific) to present the evidence, admit that there are different analysts who have proposed different mechanisms to explain the existence of this evidence, and then to encourage students to use their own critical thinking skills to compare the strengths and weaknesses of each explanation point-by-point (one hypothesis may explain one group of data better than another hypothesis, while having more difficulty with different data than the other hypothesis).

In fact, as Walt Brown explains on this page of his online book, the creation of the laminae in the Green Mountain Formation is by no means an "open-and-shut case." For starters, the varves in the Green River Formation cover tens of thousands of square miles: this fact alone is difficult to explain by uniformitarian processes involving an enormous lake system operating undisturbed for millions of years. As Dr. Brown points out, the layers are extremely uniform and parallel: under the conventional explanation, one might expect changing stream patterns to come and go during the course of millions of years which would disturb the varve-production in one area but not another, or differing weather patterns to lead to differing thicknesses in one region of the formation that was far removed from another region (isn't it reasonable to believe that weather in Utah might have been different from the weather in Wyoming or Colorado during some of those winters or summers over that two million year period?). If we subscribe to the tectonic theory, we might even expect some uplift to change the terrain in some portion of this extensive formation and not another, if we truly believe that six million years were involved.

In addition, Dr. Brown points out that the Green River Formation is also an incredibly fossil-rich area. The National Park Service explains that "the quality of fossil preservation is extraordinary, nearly unparalleled in the fossil record" (they provide a photo gallery of fossils here).

In addition to finely-preserved birds (some with fossilized feathers), reptiles, and mammals, the Green Mountain Formation also preserves countless fossil fish, which Dr. Brown notes are "flattened, paper-thin." Literally thousands of these were preserved in the act of swallowing other fish. This fact is extremely difficult to explain under conventional uniformitarian models. Explaining why these fish are pressed paper-thin is difficult enough: explaining why so many apparently died while eating another fish without positing some catastrophe is even more difficult.

As it turns out, the hydroplate theory (which also provides a very credible explanation for the formation of the Grand Canyon and for some of the geological evidence surrounding the Grand Canyon region) also provides a coherent explanation for the formation of the Green River varves and the presence of so many well-preserved fossils in the same place. The hydroplate theory explains the formation of these varves as being due to the process of liquefaction, which would have been present during a global flood. Dr. Brown explains the principles of liquefaction in a section of his book beginning here and continuing through the pages following.

During the flood event described in the hydroplate theory, tons of water and eroded sediments would have rapidly buried billions of organisms. During the period in which the floodwaters prevailed upon the earth, powerful hydrodynamic processes similar to those caused by ocean waves today would tend to sort sediments into layers, and water lenses would form in between these layers. When the water lenses collapsed, fossils inside would tend to be flattened. Dr. Brown explains:
Because dead fish usually float, something must have pressed the fish onto the seafloor. Even if tons of sediments were dumped through the water and on top of the fish, thin layers would not lie above and below the fish. Besides, it would take many thin layers, not one, to complete the burial. We do not see this happening today.

However, liquefaction would sort sediments into thousands of thin layers. During each wave cycle, liquefaction lenses would simultaneously form at various depths in the sedimentary column. Fish that floated up into a water lens would soon be flattened when the lens finally drained.
This explanation is at least as satisfactory as the conventional explanation, and for much of the evidence found in the Green River region it is far more satisfactory. Further, we have seen in previous discussions that the hydroplate theory can provide a far better explanation for many other "extreme" geological formations found around the world (some others include Uluru and Kata Tjuta, the "White Cliffs of Albion," submarine canyons such as the Ganges Fan and others around the world, fossil evidence in the Arctic and Antarctic, and many others).

Certainly the possibility that there are other explanations for the Green River varves should be carefully considered, rather than dismissed, ridiculed, and marginalized.