Zircon U/Pb Radiogenic Dating of the Great Valley Formation (2015)
Undergraduate: Amanda Sutter
Faculty Advisor: Drew Coleman
Department: Geology
Using zircon U/Pb radiogenic dating methods, I gathered geologic ages of a number of samples of ash layers from the Great Valley Formation in central California to better determine the boundaries between ages in the Lower Cretaceous period of the Geologic Time Scale. By precisely dating these samples, we can better determine the order of events of various geologic, biologic, and climatic events during this time period. Through the completion of my project, I have found that the Berriasian-Valanginian boundary is around 138 Ma, the Valanginian-Hauterivian boundary is 133.66 +/- 0.14 Ma, and the Barremian-Aptian boundary is 124.07 +/- 0.13 Ma; all of which shift the previously decided boundaries of these ages in the currently accepted Geologic Time Scale.