How can the Earths geologic history be sequenced from the fossil and rock record?
1. Geologists have divided the Earth’s history into time units based upon the fossil record. The Reference Tables shows this on pages 8 & 9 with the “Geologic History of New York at a Glance”. 2. Plate motions and mountain building events have been placed on the geologic time scale. These events can be identified and sequenced with geologic periods using the E. Sci. Ref. Tables. 3. Human existence has been very brief in comparison with the expanse of geologic time. Scaled time lines help to show this. 4. Buried erosional surfaces (unconformities) indicate gaps in the geologic time record. Determine the time periods in New York State for which the geologic record has been lost. 5. Assuming that “the present is the key to the past”, we can infer past events from the rock record. (uniformitarianism) Show current geologic processes that are examples of those processes preserved in rock. D. How can the absolute age of a rock be determined? 1. Some rocks contain elements with atomic nuclei t
