The geologic history of Death Valley is complex: it involves not only fault activity at various times, but also crustal sinking, volcanic activity and erosion. In literal geological terms, Death Valley is a graben; that is, a rift valley formed by the sinking of the bedrock lying between parallel, uplifted, tilt-block mountain ranges. In this case, the two mountain ranges are the Amargosa to the east and the Panamints to the west. 

How Death Valley Formed

Death Valley's current landscape is the result of slow, massive changes over many centuries. The earliest rocks, dating from the Precambrian Era, are visible today in sections of the Black and Panamint mountains. During the Paleozoic Era (300 to 500 million years ago), seas covered the region, leaving layers of marine sediment and the fossils of many types of marine animals. The present landscape was shaped between 5 million and 35 million years ago, during the Cenozoic Era.

After faults formed in the earth's crust, exceptional folding and volcanic action uplifted the mountain ranges and lowered the valley floor, creating a graben. The present floor is dropping on one side and is actually 8,000 to 10,000 feet above its bedrock base. Intervening space is filled by the massive amount of debris eroded from the surrounding mountains over time.

During Ice Ages, Death Valley was periodically filled by large lakes. Their waves carved terraces on the bordering rocks, and their evaporation left alternating layers of mud salt deposits that now cover the basin's floor. 

The process of geologic change continues today. The mountains are constantly eroding; their remains spill out into the valley in the enormous alluvial fans which spread like aprons at the mouth of every canyon. Rainfall sends torrents of water down to cut paths through the rocks, subtly altering the schemes of form and color along Artist's Drive, at Zabriskie Point and within Golden, Mosaic, Grotto, Marble and Titus canyons.