Perhaps the sea levels retreated and what was once a perfect environment for deposition (shallow sea) was then several miles inland.Or maybe uplift exposed once safely buried rock layers.
The idea of radioactive decay and half lives, a type of absolute dating, is shown through an activity using M&M's candy and graph paper. Sequencing Time, University of California, Berkeley. This 5-12-grade activity lets students place parts of their own life story into a time line so that they can better understand how geologic time is reconstructed by scientists.
Right: A crushed ammonite from the Shales-with-Beef Member, found on the foreshore beneath Black Ven.
Left: A large nautilus in cross-section on the surface of a foreshore boulder at Monmouth Beach, beneath Ware Cliffs. Norman Mac Leod and Dr Paul Davis at the Natural History Museum of London for their continued support and guidance identifying the stratigraphy of Black Ven and Church Cliffs.
Radiometric Dating and the Geologic Time Scale, The Talk Origins Archive. Provides brief overview of (1) relative dating and stratigraphic methods, (2) absolute dating and radiometric dating, including a table with parent to daughter isotopes and half lives of those isotopes commonly used in radiometric dating, (3) paleomagnetics and (4) geologic time. Includes tables of common radioactive parent isotopes and their stable daughter products, and half lives of common radioactive isotopes.
This group is dedicated to providing information about the scientific method as it concerns the idea of evolution in the Creation/Evolution debate.