Post -3.3 Ma geometric, structural, and kinematic changes in the Black Mountains and Towne Pass fault zones led to the break up of Furnace Creek basin and uplift of the Copper Canyon and Nova basins. Based on the new stratigraphy, the Death Valley fault system can be divided into four main fault zones: the dextral, Quaternary-age Northern Death Valley fault zone the dextral, pre-Quaternary Furnace Creek fault zone the oblique-normal Black Mountains fault zone and the dextral Southern Death Valley fault zone. This paleolake extended from the Furnace Creek to Ubehebe. Facies associated with the tephra beds show that ?3.3 Ma the Furnace Creek basin was a northwest-southeast-trending lake flanked by alluvial fans. This new geochronology also establishes maximum and minimum ages for Quaternary alluvial fans and Lake Manly deposits. New geologic formations have been described in the Confidence Hills and at Mormon Point. These tephra beds and tuffs establish relations among the Upper Pliocene to Middle Pleistocene sedimentary deposits at Furnace Creek basin, Nova basin, Ubehebe- Lake Rogers basin, Copper Canyon, Artists Drive, Kit Fox Hills, and Confidence Hills. We present tephrochronologic and paleomagnetic data in the context of testing the paleohydrologic connections with respect to the common collection point of the Amargosa, Owens, and Mojave Rivers in Death during successive time periods: (1) the late Pliocene to early Pleistocene (3-2 Ma), (2) early to middle Pleistocene (1.2-0.5 Ma), and (3) middle to late Pleistocene ( 3.58 Ma to < 1.1 ka.
Recent mitochondrial deoxyribonucleic acid (mtDNA) studies show a common pupfish (Cyprinodontidae) ancestry in this region with divergence beginning 3-2 Ma. Geological and biological studies have tended to support this hypothesis and a hydrological link that included the Colorado River, allowing dispersal of pupfish throughout southeastern California and western Nevada. Ebbs, V.M.ĭuring glacial (pluvial) climatic periods, Death Valley is hypothesized to have episodically been the terminus for the Amargosa, Owens, and Mojave Rivers. Reconstructing late Pliocene to middle Pleistocene Death Valley lakes and river systems as a test of pupfish (Cyprinodontidae) dispersal hypotheses
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