THE SHOSHONE ROADCUT REVISITED: EXPLORATIONS INTO COMBINING 2D, 2.5D, AND 3D TECHNIQUES TO CREATE A FULLY-REALIZED 3D MODEL OF THE RESTING SPRING/NOPAH RANGES, DEATH VALLEY REGION, CALIFORNIA

The Roadcut, located ~5km east of Shoshone, CA that is traditionally associated with Bennie Troxel, is a classic field trip stop. We have re-mapped this classic locality using some of the most modern techniques available. The goals were creating a fully-realized 3D model of the region and also testing how compatible traditional 2D mapping practices are with modern mapping techniques. An area of approximately 30 km², from the Roadcut proper to north of the Gerstley Mine, was mapped using satellite ortho-imagery, Google Earth, GIS based and GPS assisted field digital mapping, and 3D mapping on a high-resolution point cloud generated from photographs acquired with both a drone equipped with a GoPro camera and a fixed-wing, single-engine aircraft using a handheld DSLR camera. The resulting end-product is a robust, high-resolution 3D model with a resolution at decimeter level. Mapping on this model was then compared to mapping by Heydari (1982). The largest discrepancies between the digital mapping and Heydari’s fixed scale, paper mapping are an unrecognized 1.25km long anticline located approximately 1.5 kilometers north of the Roadcut, a large, slightly northwest trending normal fault that is splitting the Resting Spring range at the level of the Cambrian Bonanza King unit approximately 3.5 kilometers north of the Roadcut, recognition of previously unmapped Cambrian Nopah Formation along the ridgeline that faces west towards the Amargosa Valley, and a new interpretation of a series of normal faults that repeats the lower Nopah Formation and the upper Bonanza King Formation in the footwall of the Gerstley Thrust from the Resting Thrust to the Amargosa Valley. Work in progress will provide an updated 3D geologic map of the bulk of the Resting Spring and Nopah Ranges with reassessments of the thrust correlations to adjacent ranges.