Gateway to the Mysteries

The Badwater Basin in the Death Valley in California is an endorheic basin, a closed drainage basin, that retains all water with no outflow. It contains a dried out salt lake full of mud cracks. Temperatures are oven-like and hold the record for North America’s hottest place. Moreover, Badwater is 86 m (282 ft) below sea-level.
About 10000 years ago at the end of the last ice age, many rivers from melting glaciers discharged into the large depression to the east of the Sierra Nevada mountain range. The entire region was covered by Lake Manly. Due to postglacial natural global warming, the glaciers disappeared and the rivers ran dry. The waters of Lake Manly began to evaporate leaving behind the salt washed into the lake. Extensive layers of evaporites from that era mark today’s landscape of Death Valley. The salt sediments form polygonal pancakes like colliding ice floes. The heat in this desert is almost intolerable to humans and constantly cracks the thin salt crust. Below these fissures the hyper saline water evaporates leaving additional salt crystals behind.
Death Valley is located in a rift valley similar to the area of the African rift system where divergent continental plate drift allowed the transgression of the Red Sea. This rifting process failed repeatedly in Death Valley. About 12 to 15 million years ago the mid-oceanic ridge of the Pacific Ocean, called the East Pacific Rise, began cutting into the margin of the North American Plate, initiating the rift. The result is a sunken valley with occasional volcanic activity already reaching the surface. This is the first indicator of volcanic oceanic crust reaching the surface and ripping the continent apart. The Pacific Ocean has not yet drained into this basin. However, it did already in the Gulf of California.
The rain shadow of the Sierra Nevada to the west causes the arid geomorphology. The peaks of the High Sierra at 14800 ft (4500 m) height directly face the rift valley system at 282 ft (-86 m) height within a distance of only 136 km (84.6 mi). By descending into Death Valley, the air temperature increases by 5.5°F per 1000 ft (1°C per 100 m). The valley floor is about 3280 ft (1000 m) lower than the surroundings resulting in additional 10 °C of warming making Death Valley as hot as 135°F (57°C). The valley is already filled with sediments up to 10000 ft (3 km) thick resulting in an absolute relief difference of 20000 ft (6 km).
Once the drift continues, the Pacific Ocean will flood this valley.

August 2006
Canon 20D, EF-S 10-22 mm, f/22, 1 sec, ISO 100, tripod
Basin and Range Gallery » Gateway to the Mysteries