Research
U-Th-Pb Geochronology
A fundamental question in geochronology and geochemistry concerns the temporal evolution of atmospheric oxygen and its relationship to the evolution of complex life.
Fluctuations in atmospheric oxygen around the Great Oxygenation Event (GOE)
What caused the major rise in atmospheric oxygen leading up to the GOE? Did atmospheric oxygen levels remain elevated post-GOE? How does this impact the evolution of complex life?
The Great Unconformity Formation
Is the formation of The Great Unconformity at the boundary of the ~1.73 Ga Payson Ophiolite and Cambrian Tapeats sandstone, Arizona, due to intensive physical weathering associated with the Neoproterozoic Snowball Earth events?
