Friday, May 11, 2012

Rocks and Layers

In a prior essay, we looked at the geology of sedimentary rocks and at the conclusions that can be drawn from the existence of the layers.  We saw that a presupposition of uniformitarianism yields a conclusion more in tune with the theory of Evolution, but a presupposition of catastrophism produces a conclusion that favors a world wide flooding over a short period of time.

Uniformitarianism is currently in vogue, but there is so much to commend Catastrophism that some geologists try to join the two concepts into a different theory called Punctuated Uniformitarianism, to account for the evidence that supports both theories.  This theory suggests long periods of uniform activity punctuated by major catastrophic events.

Part of the reason for the need for a combined theory is found in the layers, themselves.  What makes a layer a layer is the fact that everything in it is similar material.  Being similar to itself means it is different from the layers above and below it.

The homogeneity of a layer causes some logical problems.  Why would a layer contain only a limited number and type of life forms?  If you would look in a river delta or a lake where dead things are being deposited by current runoff and erosion, you will find multiple life forms, including both unicellular and complex. You may find  algae, oysters, alligators, fish, and perhaps, a human corpse.  These things are all living in today's ecosystem, so if they died and were fossilized, the deposits would contain a diversity of fossil life forms, not uniform layers of index fossils characterizing just one group or age, unless there was something other than time, e.g., density, by which the layers were established.

The interfaces between two layers also present problems.  Was there a layer that originally existed between the two layers we find in today's rocks?  And did that layer get eroded (uniformly across the globe) so that all the life forms in it were totally annihilated by some global events?  The reason this is an important question is because Uniformitarianism and its associated consequence, Evolution, would require that life forms represented in one layer evolve to life forms in a later layer.

There would need to be evidence of gradual changes from one life form in one layer to more complex forms in the next layer.  Because there are no fossils showing intermediate forms, these "missing links" (missing between any fossil and its supposed ancestor, not just ape and man), must be assumed to be in the layers that are not present, i.e., the layers that must have been washed away by erosion, washed away, incidentally, without any evidence or any fragments of preexisting fossils in more recent layers that should contain such runoff.  [Note: this kind of argument is called "argument from silence," indicating it is implied by the absence of data.  Although it is not necessarily a fallacy, an argument from silence is weak, at best.]  The global extent of the layers and the uniformity of the extant layers makes the absence of any intermediate forms anywhere, a convincing statement.  Sometimes, the absence of data is because it never existed in the first place.

The third problem evinced by layers is the limestone/coral problem.  Some limestones are formed mostly of the fossilized remains of coral.  Coral are known to grow only at certain temperatures and water depths, so coral-limestone should form in linear bands along the coastlines of continents.  The fact that some of the layers, e.g., in the southeastern United States consist of many miles of coral-based limestones, indicates that the delicate ecosystems that support coral growth moved over time.  It is postulated that the limestones in the layers in the southeastern US were formed as the polar ice caps melted and the ocean advanced onto the continent, and then moved back to their present locations.  This would mean that these limestone regions represent large periods of time and that they cut across time, not that they represent a particular time.

Here we see some of the problems posed by the existence of layers.  The problems must be accounted for by the presuppositions. Otherwise, the presuppositions need to be modified or rejected in order to account for the data problems.

As we have seen, presuppositions determine conclusions, but presuppositions must also be consistent with the data being analyzed.  Remember that presuppositions are just paradigms that are accepted on faith.  Clark Pinnock once said, "The heart cannot delight in what the mind rejects as false." (Set Forth Your Case, Craig Press, Nutley, New Jersey, 1968.) Your faith must be reasonable to you, but, in the end, it is faith, nonetheless.

No comments: