Join us April 21st for the GeoSymposium field trip, hosted by the UNLV Geoscience department and lead by Dr Michael Wells and his graduate students.
This field trip is free to attend thanks to the generosity of Newmont Mining Corporation.
This field trip will focus on new constraints on the timing of crustal shortening in the Sevier fold-thrust belt in the Spring Mountains. The thrust belt spans the transition from the thick Late Precambrian to Paleozoic passive margin strata to thinner transitional platform strata. Timing constraints are provided by scarce synorogenic sedimentary deposits associated with the eastern thrusts (Red Springs, Wilson Cliffs, Contact, and Bird Springs thrusts) in the transitional strata and by cooling histories of Late Precambrian clastic strata in western thrust sheets (Gass Peak, Wheeler Pass, Chicago Pass, Nopah Peak thrusts). We will visit outcrops of the Brownstone Basin conglomerate in Brownstone Basin (BB) of Red Rock Canyon Conservation Area and discuss evidence for deposition during advance of the Red Springs-Wilson Cliffs thrust and new timing constraints from detrital zircon U-Pb geochronology. Evidence for deformation during advance of the Red Springs-Wilson Cliffs thrust will be viewed near Willow Springs, along with evidence for a hiatus in deformation and significant erosion in between motion on the Wilson Cliffs and younger Keystone thrusts. Finally, we will review new results on the timing of motion on the easternmost thrusts as constrained by low temperature thermochronology, from an overview atop the Wilson Cliffs near Mountain Spring summit (MSS). This trip will involve two hikes of ~1.8 miles (BB) and 3.0 miles (BSR) roundtrip, to reach the exposures of the Cretaceous synorogenic deposits and the final overview stop on the Wilson Cliffs thrust.