The sequence stratigraphy of the Middle Cambrian Wheeler Formation in the Drum Mountains of west central Utah.

摘要

The majority of the Middle Cambrian Wheeler Formation in the Drum Mountains was deposited during a single 3rd order sequence. Superimposed onto this sequence are three indistinct 4th order cycles and twenty distinct 5th order cycles. These higher order cycles were likely deposited within short intervals of geologic time (20 4 to 405 ky).;Deposition of the Wheeler Formation in the Drum Mountains was controlled by eustacy and tectonics. Local normal faulting associated with Middle Cambrian post-rifting thermal subsidence may have caused some of the 5th order cycles;The lower sequence boundary zone occurs within the limestones of the Swasey Formation. The Transgressive Surface is the contact between the Swasey and Wheeler Formations. The Maximum Flooding Surface is located near the top of the lower Wheeler Formation, which also approximates the base of the Ptychagnostus atavus range zone. The upper sequence boundary is marked by stromatolites.