On the importance of non-uniform tilt, strike slip, and hydrogeology in shaping the Neogene tectonics of the eastern Lake Mead area
On the importance of non-uniform tilt, strike slip, and hydrogeology in shaping the Neogene tectonics of the eastern Lake Mead area (in Neogene deformation between central Utah and the Mohave Desert, R. Ernest Anderson (editor))
Special Paper - Geological Society of America (October 2013) 499: 69-94
The eastern Lake Mead region, central Basin and Range Province, contains an abrupt boundary between the Colorado Plateau and Basin and Range, west of which decades of tectonic studies have documented extreme (at least 60 km) westerly translation of the Frenchman Mountain structural block away from the boundary, currently at a distance of approximately 95 km. Detachment-style faulting and large lengthening in the eastern Lake Mead region are generally accepted (eight of ten papers in a 2010 compilation of recent research) as integral to the large province-wide lengthening at this latitude. Presented here is field geologic evidence of the contribution of karsting and tilting on multiple fixed axes to the Miocene strain history. Together with newly recognized strike slip on northerly striking faults, associated steep-axis bending, and evidence against fault listricity, the region probably contributes little to Province-wide lengthening, but estimates of westerly translation of the Frenchman Mountain block remain unchanged.