Soggy Dry Lake

Soggy Dry LakeJohnson Valley

Playa formation – “A playa is a dry, vegetation-free, flat area at the lowest part of an undrained desert basin. It is a location where ephemeral lakes form during wet periods, and is underlain by stratified clay, silt, and sand, and commonly, soluble salts. Playas occur in intermountain basins throughout the arid southwestern United States. Although playas may appear as featureless plains, they are rich in features and characteristics that can reveal information about climates, past and present. “

Rand Schist

Rand Schist of Rand Mountains, Schistose rocks of Rand Mountains described briefly ·by Hess (1910, p.28-29, 46) and by Hershey (1902a, p. 273); named, described, and mapped as Rand Schist by Hulin ( 1925,p. 23-31, pl. 1), and officially adopted for use in this report.

Rand Schist folded into anticlinal arch plunging gently westward as indicated by foliation attitudes (figs. 3, 4). On north, schist overlain by gneissic rocks (Johannesburg Gneiss of Hulin), separated by possible fault or thin zone of cataclastic(?) transitional rock; on south and near Randsburg, schist intruded by quartz monzonite; extends unknown distance westward under ·alluviated valley, possibly to Garlock fault. Possibly 10,000 feet of schist exposed; lithology identical to that of Pelona Schist of Sierra Pelona and of Tehachapi Mountains; gray schist, predominating over green schist, contains occasional pods of fibrous actinolite schist; thin layers of quartzite and of marble, mostly in southern and western exposures. In exposures northeast of Johannesburg, albite content of schist increases to 75 percent.

Type locality of Rand Schist designated as generally north-dipping section in Rand Mountains (fig. 4), from quartz monzonite intrusion just south of Randsburg northward to contact with overlying(~) gneiss about 3 miles north of Randsburg.

From;

Areal Geology of the Western Mojave Desert California
By THOMAS W. DIBBLEE, ]R.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 522 – 1967

Geology List

Geology Thumbnail Index

Mojave Desert Geology

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California’s geomorphic provinces are naturally defined geologic regions that … Earthquakes & Faults · San Andreas Fault. Summary of the earthquake fault …

Cajon Pass Geology

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Heteromyid rodents from Miocene faunas of the Mojave Desert, Southern California. Natural History Museum of Los Angeles County. Science Series 41; p. 213-236.

Geology of Red Rock Canyon

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Red Rock Canyon California State Park. The geologic story of Red Rock Canyon is told by its …

Death Valley Geology

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California/Nevada Death Valley Regional Geology. Field Trip Guide. Walk Through Time. Badwater with Telescope …

Geology of Mojave Preserve

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Mesozoic Rocks. Source – NPS, Cinder cones national natural landmark. Kelso Dunes, Mojave Preserve, Eastern Mojave Desert Banshee …

The Mojave Desert – Shaping the Classic American Desert

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The area of most dramatic relief is around Death Valley, California, where the elevation drops from 3,400 m above sea level at Telescope Peak to 88 m below sea …

Desert Sand Dune Geology

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The Geology of Sand Dunes. While one-quarter to one-third of the world’s deserts are covered with sand, little research has taken …

Mojave Preserve Geology – Landforms

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Desert landscape and surface processes study, Mojave National Preserve.

Hole in the Wall – Mojave Preserve

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Mojave Preserve – Geology. Hole-in-the-Wall. Hidden violence. Visitors to Mojave National Preserve are fascinated by the brightly colored, …

The Mojave River and Associated Lakes – Mojave Desert Geology

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Desert landscape and surface processes study, Mojave National Preserve.

Geology – Death Valley Rock Samples – Mojave Desert

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A rock formation is a body of rock of a considerable extent with distinctive characteristics that allow geologists to map, describe, and name it. The sample rocks …

Geology of the Death Valley Region

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The three sites in this area lie in the extreme southeast corner of Death Valley National Park immediately west of California Highway 127 which provides the …

Introduction to Geology of the Mojave Desert

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Far from being static, the geology of Earth is dynamic, in constant motion and change. The crust is a puzzle made up of tectonic plates, shifting against …

Geology of Joshua Tree

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Mojave Desert Geology: Joshua Tree National Park – Nature & Environment. Geology of Joshua Tree. Geologic Displays. The park encompasses some of the most …

Earthquake Faults: Mojave Desert Geology

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Geology: Earthquakes & Faults: California straddles the juncture of two great crustal plates: the Pacific plate and the North American plate.

Desert Sand Dune Geology

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Wind-induced Sand Movement. Photo of a dust devil on Soda Lake in the Mojave Preserve transporting sand. Individual sand grains are moved under the force of the …

Rock Formations – Mojave Desert

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Trona Pinnacles. This eerie, fantastic landscape is one of the most unique geological features in the California desert. These … Vasquez Rocks. These towering …

Desert Landforms & Surface Processes

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Historic weather data for the Eastern Mojave Desert is relatively scarce because there is no significant … Geologic History. The oldest rocks exposed in the …

Geology of Mono Lake

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This ongoing process has created the majestic contrast of a desert lake bordered by high mountain peaks. As the western floor of the Mono Basin slipped …

Geology Tour Road

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Map, photos and virtual tour of the Geology Tour Road in Joshua Tree National Park.

Introduction to the Arch Rock Geology tour

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Geology tour of White Tank Arch Rock in Joshua Tree National Park.

The Geology of the Mojave Desert

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The earliest rock, related to the metamorphic gneiss and schist at the bottom of the Grand Canyon, has little exposure in the Mojave, but can be seen at Saddle …

Magma On The Move: Geology of the Mojave Desert

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Along with the faulting, volcanic activity increased across the landscape. Igneous rock is derived from molten layers of magma beneath the Earth’s crust. Under …

Changing Climates and Ancient Lakes Mojave Desert

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Information was derived from articles within Enzel, Wells, and Lancaster (2003); [Geological Society of America Special Paper 268].

General Geologic History – Mojave Preserve – California Mojave

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Desert landscape and surface processes study, Mojave National Preserve.

Geology Road – Joshua Tree National Park

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Driving tour of Joshua Tree geology

Mitchell Caverns

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The Providence Mountains caves, like most limestone caves in other parts of the world, seem to have had a two-stage history. Most geologists who have studied …

Volcanic Rocks and Associated Landforms

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Cinder Cones and Lava Flows National Natural Landmark Area. Volcanic eruptions have occurred many times throughout the Mojave National Preserve in the geologic …

Badwater – Death Valley Geology

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Some of the minerals left behind by earlier Death Valley lakes dissolved in the shallow water, creating a briny solution. The Desert Returns. The wet times didn’t …

Geology Red Rock National Conservation Area

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For much of the past 600 million years, the land that is now Red Rock Canyon NCA was the bottom of a deep ocean basin and the western coast of North America was …

Mosaic Canyon – Death Valley Geology

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Smooth, polished marble walls enclose the trail as it follows the canyon’s sinuous curves. The canyon follows faults that formed when the rocky crust of the …