ABSTRACT
The arid western United States is the type area for asin and Range topography produced by alternating horst-graben structure or tilted fault block mountains. Early investigators such as Gilbert, Powell and Dutton, followed by Davis and Blackwelder, successfully unraveled the complex structural and geomorphic history of the Basin and Range Province by studying the mountains, the pediments and the bajadas. Little attention was paid to the lowland playa areas.
Recent studies of intermontane basins, utilizing seismic methods, drill holes and electronic enhancement of satellite imagery, reveals that the basins are unusually complex tectonic elements, parts of which have subsided (and in many cases are still subsiding) over considerable periods of geologic time. Multiple, near-parallel faults often border the grabens, the main parts of which may be displaced by intersecting fault trends. The sedimentary history, particularly of pre-late Pleistocene sections, is complex and lithologic distribution in the basins often fails to comply with “established rules”.
The common occurrence in intermontane basins of potable ground water, commercially important evaporite minerals, and uranium deposits as well as other exotic minerals, insures an ever-increasing rate of geologic study and evaluation for the immediate future.
