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Take a stroll through one of the lowest pieces of land in the Western Hemisphere (282 feet below sea level), a place that, strangely enough, also happens to be adjacent to the highest point of land in the lower 48 states of the U.S., the 14,494 ft. mountain peak of Mt. Whitney. Death Valley.
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Take a stroll through one of the lowest pieces of land in the Western Hemisphere (282 feet below sea level), a place that, strangely enough, also happens to be adjacent to the highest point of land in the lower 48 states of the U.S., the 14,494 ft. mountain peak of Mt. Whitney. Death Valley
Zabriskie Point, in midwinter. The soft sediments at Zabriskie Point were deposited in an old lake, and are being eroded into the beautiful features seen here. The snow-covered peaks in the background tower two miles above the valley floor. (Photo by Penn State graduate, now University of New Mexico professor, Peter Fawcett.)
Badwater in midwinter. Peter Fawcett, noted Penn State alumnus and University of New Mexico professor, at 282 feet below sea level. The little bit of water from a midwinter storm will evaporate quickly.
Salt flats in midwinter, Death Valley. Water, such as seen in the previous picture, carries dissolved minerals (ask a plumber who has tried to remove a faucet in a house with hard water if you don't believe this!). When the water evaporates, the salt is left. Photo by Peter Fawcett.
20-mule team. The salts deposited in Death Valley included valuable materials such as borax, containing boron dissolved from volcanic and other rocks around the valley. The salts were mined, and the borax hauled out by 20-mule teams. This is a picture from a reenactment of the mule teams, years after the mining ceased. Photo by Ed Derobertis of the National Park Service.
Probably the most familiar of the many uses of borax is in laundry detergents. Before he was president of the United States, actor Ronald Reagan advertised a laundry detergent containing borax, as shown in this photo from the National Park Service archives.
Another salt flat is shown here. Behind the salt flat, at the foot of the mountains, is an alluvial fan, a pile of gravel brought down into the valley from the mountains by streams that run for a short while after rainstorms. The vertical distance between the lowest point (end of the pink arrow) and highest point (end of the yellow arrow) on the fan is greater than the vertical distance from Spring Creek to the top of Mt. Nittany near Penn State¹s University Park Campus--the fan is taller than most eastern mountains! The scale of things in Death Valley is immense, and very difficult to comprehend. Photo by Peter Fawcett
Again, putting Penn State’s Mt. Nittany, or many other eastern mountains, into this picture wouldn’t change it much - they would reach only part of the way from the salt flat at the bottom (shown by the orange arrow) up the fan (the top of the fan is shown by the yellow arrow), far shorter than the peaks in the picture. Photo by Peter Fawcett
During the ice age, more rain fell in Death Valley because storm tracks had moved, and less water evaporated because temperatures were lower than today. A huge lake filled Death Valley then. In this rather fuzzy slide downloaded from the USGS-National Park Service web site, the horizontal lines (the ends of one are shown by the blue arrows) are old beaches from that lake. The photo of Shoreline Butte is by Marli Miller.
Some of the gravels washed into the valley by streams are shown in this photo by Peter Fawcett.
Deserts are not dominated by dunes in many places, but dunes do occur. The streams flowing into Death Valley carry salts, big rocks, but also sand. If the sand is piled by wind, beautiful forms may result, such as these. Photo by Paul Stone, United States Geologic Survey
The enigmatic Devil's Racetrack. The stones rather clearly have moved across the surface of the salt flat. Strong winds during wet times are probably involved. Perhaps a thin water layer forms in a winter storm, freezes on top on a cold night, and then the wind drags the ice carrying the rocks. Photo by Marli Miller, from the Death Valley National Park web site.
Death Valley was dropped along faults (or the mountains were raised, or both). The Hanaupah Fault (between the blue arrows) cuts the toe of an alluvial fan coming down from Telescope Peak, shown in this photo by Marli Miller from the Death Valley National Park web site.
UP A closer view of The Hanaupah Fault (between the blue arrows) as seen in the previous picture, with labels showing which side of the fault was raised (“UP”) and lowered (“DOWN”). Photo by Marli Miller, from the Death Valley National Park web site. DOWN
http://www2.nature.nps.gov/GEOLOGY/usgsnps/deva/Ubehebe_field19.jpg Peter Sanchez Hot rocks occur at shallow depth under Death Valley, and break through occasionally in volcanoes, usually coming up along faults; farther to the south, stronger volcanism has made the sea floor of the Gulf of California. In Death Valley, the eruptions are not especially strong, but they have made craters, such as those in the Ubehebe volcanic field, shown in these photos. http://marsweb.jpl.nasa.gov/missions/behind/images/ubehebe_crater.jpg http://www2.nature.nps.gov/GEOLOGY/usgsnps/deva/LUbe.jpg Marli Miller
http://wrgis.wr.usgs.gov/parks/deva/ftcin2.html Photo by Tom Bean, National Park Service Sometimes, volcanoes make small cinder cones, composed of little rocks and hardened blobs of lava thrown through the air. And, sometimes faults move rocks horizontally, as shown here (upper left without lines, and lower right with fault shown by dashed line and motion by arrows) for Split Cinder Cone in Death Valley. Most of the faulting in Death Valley is related to the dropping of the Valley and raising of the mountains, but horizontal motions such as this do occur occasionally.
