THE SUPERCONTINENT CYCLE AND THE GEOLOGIC EVOLUTION OF DEATH VALLEY

In this review paper I place the geologic history of the Death Valley region into the framework of the supercontinent cycle. We now know that Death Valley’s geologic history spans three supercontinent cycles―from the early stages of the assembly of Nuna, through the assembly and disintegration of Rodinia, to the assembly and subsequent break-up of Pangaea.

I have divided the geologic history of the Death Valley region into the following eight tectono-sedimentary episodes, each of which is connected to a particular phase of the supercontinent cycle: (1) development of the Mojave Crustal Province (crystalline basement rocks) during the assembly of Nuna; (2) development of a succession of “ChUMP” basins in central Rodinia (Crystal Spring, Horse Thief Springs, and Beck Spring formations); (3) rifting and “snowball Earth” glaciations and post-glacial sedimentation within Rodinia (Kingston Peak Formation and Noonday Dolomite); (4) rift-to-drift transition as Rodinia begins to fragment (Johnnie, Stirling, and Wood Canyon formations); (5) passive-margin sedimentation in response to thermal subsidence and also true-polar-wander-induced processes, all happening as Rodinia breaks up (Paleozoic strata); (6) compressional tectonics and plutonism associated with the assembly and subsequent fragmentation of Pangaea, and the development of an active-margin tectonic setting (Permian and Mesozoic folding and thrusting; Mesozoic plutonism); (7) low-angle Basin-and-Range extension and associated basin development and volcanism in response to the cessation of subduction of the Farallon Plate (Neogene detachment faults, basin sediments, and volcanism); (8) Neogene and Quaternary strike-slip faulting and pull-apart basin development as the shear motion between the Pacific and North American plates is translated into the East California Shear Zone.

Plenty of work remains in the effort to sort out the details of Death Valley’s geologic history, and competing interpretations will continue to be tested and argued. It is hoped that the narrative strategy presented here will assist interested non-combatants in better understanding the plate-tectonic setting in which this history evolved.