What is the geologic column?

Genesis

The geologic column is a theoretical illustration of how the sedimentary rock layers across the world are laid out.  However, nowhere on the Earth has this layer-by-layer illustration actually been found except in the pages of textbooks and in museums displays.  According to geologists, the bottom layer is the oldest type of rock and the layer at the top is the youngest.  Each layer is dated to be millions of years old. The dates of the layers are dated according to the fossils found in them, and the fossils are dated according to the layers they are found in.  This is circular reasoning and not a reliable method of measuring the age of the earth.  A global flood would better explain the layers of fossils we find today.

Theoretical layer of rocks and the fossils that are typically found in them