I would like to respond to Professor Cimbala's letter addressing the validity of the creation and evolution theories.

I find the premises by which Cimbala discounted the geologic time scale are unfounded based on geological principles.

Cimbala made the argument that the entire geologic column was created by a global flooding episode and that this one catastrophic event created enough sediment to lithify and form the geologic column.

The geologic column is the sequence of layered rocks that accumulated during the history of the Earth.

There is a host of evidence indicating the existence of earth sediments as old as 4.1 billion years, however most creationist scientists do not consider radioisotopic methods for dating rocks valid.

There is also significant fossil evidence, this is also deemed inconclusive. I would like to present yet another approach to defend the age of the geologic column.

The geologic column is made up of many separate layers.

These layers have compositions that can vary widely from the ones above and below it, for example one layer can be composed entirely of quartz, while the layer below it may contain none. Also, the mechanics of a flood can not explain sedimentary structures.

One example would be cross laminations in rocks that indicate paleoflow currents from ancient rivers.

These structures can not be reproduced in modeling of catastrophic flood depositional conditions.

This evidence supports that the geologic column was formed over the billions of years that sediments have survived on the earth.