Journey Through Time: Unraveling Earth's Story in the Rocks of Las Vegas
Xutong Guan and Joel Saylor
Sixteen undergraduate and graduate students from EOSC 448 and EOSC 546 - Advanced Field Methods participated in an unforgettable field investigation. Travelling to the US from February 16 to 25, they read the history of that is written in the rocks around Las Vegas. They paged through geologic time starting with the Great Unconformity, which showcases the “missing pages” from the story of the Earth and separates 1.7-billion-year-old Vishnu Schist from 540-million-year-old Tapeats Sandstone. Younger, Paleozoic limestones contain marine fossils and indicate how the arid Mojave desert was a broad sea with a variety of creatures. Younger still, widespread Mesozoic mudstones and sandstones—including the Aztec Formation—tell of a transition from low-energy rivers and coasts to a 350,000 km2 eolian sand sea.
The students used geological mapping in Red Rock Canyon and Buffington Pockets to reorder the geological pages, which had been shuffled by multiple faults. Measuring stratigraphic sections in the Valley of Fire State Park trained them to carefully read and interpret the sedimentary record, yielding insight into the tectonic setting in which the strata were deposited and how they relate to deformation associated with the Sevier Orogeny.
The students hiked in many breathtaking trails, and camped in picturesque red rock valleys and by fantastic Joshua trees. Together they explored the geology, cooked and ate by a flickering campfire, and slept under the bright moon and twinkling stars.
The field trip was co-led by Joel Saylor and Brett Gilley. A special thanks goes out to BHP for fully and generously subsidizing this field experience for UBC students.
Tightly folded Jurassic Aztec Formation in the footwall of the Keystone Thrust at Red Rocks Canyon. Photo by J.E. Saylor.
Chert-filled burrows in the Permian Toroweap Formation at Frenchman Mountain. Photo by J.E. Saylor.
Intense deformation in the Cambrian Bonanza King Formation at Buffington Pockets. Photo by J.E. Saylor.
Remote camping in calico-colored Jurassic Aztec Formation below distant cliffs of grey Cambrian Bonanza King Formation at Buffington Pockets. Photo by J.E. Saylor.
Fiery sunset illuminates a ridgetop tent at Buffington Pockets. Photo by J.E. Saylor.
