Badwater Basin in Death Valley, California, is an endorheic basin, a closed drainage basin that retains all its water without any outflow. It contains a dried-out salt lake covered with a network of mud cracks. Temperatures are oven-like, and the valley holds the record for the hottest place in North America. Moreover, Badwater lies 86 m (282 ft) below sea level.
About 10,000 years ago, at the end of the last ice age, numerous rivers fed by melting glaciers discharged into the large depression east of the Sierra Nevada mountain range. The entire region was covered by Lake Manly. Due to natural global warming after the ice age, the glaciers disappeared and the rivers gradually ran dry. The waters of Lake Manly began to evaporate, leaving behind the salts that had been washed into the lake. Extensive layers of evaporites from that era mark today’s landscape of Death Valley. The salt sediments form polygonal patterns resembling colliding ice floes. The heat in this desert is almost intolerable for humans and constantly cracks the thin salt crust. Beneath these fissures, hypersaline water evaporates, leaving additional salt crystals behind.
Death Valley is located in a rift valley similar to the region of the African Rift System, where divergent continental plate movement allowed the Red Sea to form. This rifting process repeatedly failed in Death Valley. About 12 to 15 million years ago, the mid-ocean ridge of the Pacific Ocean, called the East Pacific Rise, began cutting into the margin of the North American Plate, initiating the rifting. The result is a sunken valley with occasional volcanic activity already reaching the surface. This is the first indication of volcanic oceanic crust reaching the surface and beginning to tear the continent apart. The Pacific Ocean has not yet flooded this basin. However, it has already done so farther south in the Gulf of California.
The rain shadow of the Sierra Nevada to the west causes the arid geomorphology of Death Valley. The peaks of the High Sierra, reaching 14,800 ft (4,500 m), directly face the rift valley at 282 ft (-86 m) within a distance of only 136 km (84.6 mi). As air descends into Death Valley, its temperature increases by about 5.5°F per 1,000 ft (1°C per 100 m). The valley floor lies about 3,280 ft (1,000 m) below its surroundings, resulting in an additional 10°C of warming and allowing Death Valley to reach temperatures as high as 135°F (57°C). The valley is already filled with sediments up to 10,000 ft (3 km) thick, resulting in an absolute relief difference of about 20,000 ft (6 km).
Once the rifting continues, the Pacific Ocean will eventually flood this valley.
