Ubehebe Crater
Encyclopedia
Ubehebe Crater is a large volcanic crater
of the Ubehebe Craters
volcanic field in the northern half of Death Valley
, in Death Valley National Park
, California
.
. The crater is half a mile (one kilometer) wide and 500 to 777 feet (150 to 237 m) deep. The age of the crater is estimated from 2,000 to 7,000 years old. "Ubehebe" is a Timbisha
Native American word meaning "Big basket in the rock."
migrated close to the surface and the heat of the magma flashed groundwater into steam
, throwing large quantities of pulverized old rock and new magma across the stony alluvial fan
draped across the valley floor. The magma rose through a fault that lies along the western base of Tin Mountain. Movement on this fault was responsible for uplift of the entire Cottonwood Mountains
range.
by geologists and the pits created are known as maar
s. Ubehebe was the last and largest in series of similar eruptions in the immediate area (its eruption exceeded the tensile strength of the bedrock by 10 times). Earlier eruptions created a group of much shallower maars to the south and another to the west. Little Hebe is a spatter cone that grew in the middle of one of the largest maars in the south group. The only significant deposit of lava in the volcanic field is contained in Little Hebe.
All of the maar-forming eruptions sent out fallout debris that mantled a broad area around the volcanic field (dozens of steam explosions issued from Ubehebe alone). The resulting light to dark gray cinder deposits consist of finely fragmented volcanic rock
mixed with pulverized bedrock and are thickest immediately next to Ubehebe (80 feet; 25 m). Rill
s and gullies
that were 15 to 20 foot (4.5 to 6 m) deep dissected the area prior to the eruptions and were buried by the fallout. Erosion
has since re-excavated these features, exposing layers of cinder that still overlay adjacent ridges.
A type of pyroclastic flow
called a base surge was sent out of Ubehebe by one of the explosions. It started after a large column of debris were thrown skyward began to collapse. A doughnut
-shaped cloud of hot ash and gas (the base surge) sped 100 to 200 mph (160 to 320 km/h) from the base of the column while staying close to the ground, plastering the Ubehebe-facing side of all objects in the area.
-aged mostly reddish orange-colored conglomerate
makes up the exposed bedrock in Ubehebe's walls. These sediment
s were deposited by stream
s and contain limestone
, mudstone
, quartzite
and volcanic cobbles that are up to 8 inches (20 cm) in diameter. There is also a difference in color between these seabed sediments: On the left these sediments are yellowish in hue while on the right they are orange. The reason is due to a fault that separates the two different sedimentary units; over time at least 400 feet (120 m) of vertical displacement along this fault has resulted in the abutment of these two different sedimentary units. Fallout debris dip 30 feet (9 m) over the fault scarp
on the pre-eruption surface but have not been offset by it.
Within Ubehebe small alluvial fan
s have been built on the crater wall along with talus
slumps from debris flow
s. White silt
covers the crater bottom of Ubehebe and some surrounding craters.
Wind
s at the rim of Ubehebe are very strong and often gust above 50 mph (80 km/h).
Volcanic crater
A volcanic crater is a circular depression in the ground caused by volcanic activity. It is typically a basin, circular in form within which occurs a vent from which magma erupts as gases, lava, and ejecta. A crater can be of large dimensions, and sometimes of great depth...
of the Ubehebe Craters
Ubehebe Craters
The Ubehebe Craters are an isolated group of overlapped maars in the Cottonwood Mountains, beyond the upper end of Death Valley, in Inyo County, California, U.S....
volcanic field in the northern half of Death Valley
Death Valley
Death Valley is a desert valley located in Eastern California. Situated within the Mojave Desert, it features the lowest, driest, and hottest locations in North America. Badwater, a basin located in Death Valley, is the specific location of the lowest elevation in North America at 282 feet below...
, in Death Valley National Park
Death Valley National Park
Death Valley National Park is a national park in the U.S. states of California and Nevada located east of the Sierra Nevada in the arid Great Basin of the United States. The park protects the northwest corner of the Mojave Desert and contains a diverse desert environment of salt-flats, sand dunes,...
, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
.
Geography
Ubehebe Crater is located at the north tip of the Cottonwood MountainsCottonwood Mountains
The Cottonwood Mountains range is found in Death Valley National Park in Inyo County, California, U.S.The range lies just to the northwest of the Panamint Range at the top of Death Valley, and run in a north-south direction....
. The crater is half a mile (one kilometer) wide and 500 to 777 feet (150 to 237 m) deep. The age of the crater is estimated from 2,000 to 7,000 years old. "Ubehebe" is a Timbisha
Timbisha
The Timbisha are a Native American tribe federally recognized as the Death Valley Timbisha Shoshone Band of California. They are known as the Timbisha Shoshone Tribe and are located in south central California, near the Nevada border.-History:The Timbisha have lived in the Death Valley region of...
Native American word meaning "Big basket in the rock."
Geology
The crater was formed when magmaMagma
Magma is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals and dissolved gas and sometimes also gas bubbles. Magma often collects in...
migrated close to the surface and the heat of the magma flashed groundwater into steam
Steam
Steam is the technical term for water vapor, the gaseous phase of water, which is formed when water boils. In common language it is often used to refer to the visible mist of water droplets formed as this water vapor condenses in the presence of cooler air...
, throwing large quantities of pulverized old rock and new magma across the stony alluvial fan
Alluvial fan
An alluvial fan is a fan-shaped deposit formed where a fast flowing stream flattens, slows, and spreads typically at the exit of a canyon onto a flatter plain. A convergence of neighboring alluvial fans into a single apron of deposits against a slope is called a bajada, or compound alluvial...
draped across the valley floor. The magma rose through a fault that lies along the western base of Tin Mountain. Movement on this fault was responsible for uplift of the entire Cottonwood Mountains
Cottonwood Mountains
The Cottonwood Mountains range is found in Death Valley National Park in Inyo County, California, U.S.The range lies just to the northwest of the Panamint Range at the top of Death Valley, and run in a north-south direction....
range.
Eruptions
The resulting large steam explosions are called a hydrovolcanic or phreatic eruptionPhreatic eruption
A phreatic eruption, also called a phreatic explosion or ultravulcanian eruption, occurs when rising magma makes contact with ground or surface water. The extreme temperature of the magma causes near-instantaneous evaporation to steam, resulting in an explosion of steam, water, ash, rock, and...
by geologists and the pits created are known as maar
Maar
A maar is a broad, low-relief volcanic crater that is caused by a phreatomagmatic eruption, an explosion caused by groundwater coming into contact with hot lava or magma. A maar characteristically fills with water to form a relatively shallow crater lake. The name comes from the local Moselle...
s. Ubehebe was the last and largest in series of similar eruptions in the immediate area (its eruption exceeded the tensile strength of the bedrock by 10 times). Earlier eruptions created a group of much shallower maars to the south and another to the west. Little Hebe is a spatter cone that grew in the middle of one of the largest maars in the south group. The only significant deposit of lava in the volcanic field is contained in Little Hebe.
All of the maar-forming eruptions sent out fallout debris that mantled a broad area around the volcanic field (dozens of steam explosions issued from Ubehebe alone). The resulting light to dark gray cinder deposits consist of finely fragmented volcanic rock
Volcanic rock
Volcanic rock is a rock formed from magma erupted from a volcano. In other words, it is an igneous rock of volcanic origin...
mixed with pulverized bedrock and are thickest immediately next to Ubehebe (80 feet; 25 m). Rill
Rill
A Rill can be a:*1.) natural fluvial topographic feature;*2.) functional constructed channel to carry a water supply from a water source some distance away;*3.) aesthetic garden water feature.-Natural:...
s and gullies
Gully
A gully is a landform created by running water, eroding sharply into soil, typically on a hillside. Gullies resemble large ditches or small valleys, but are metres to tens of metres in depth and width...
that were 15 to 20 foot (4.5 to 6 m) deep dissected the area prior to the eruptions and were buried by the fallout. Erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...
has since re-excavated these features, exposing layers of cinder that still overlay adjacent ridges.
A type of pyroclastic flow
Pyroclastic flow
A pyroclastic flow is a fast-moving current of superheated gas and rock , which reaches speeds moving away from a volcano of up to 700 km/h . The flows normally hug the ground and travel downhill, or spread laterally under gravity...
called a base surge was sent out of Ubehebe by one of the explosions. It started after a large column of debris were thrown skyward began to collapse. A doughnut
Doughnut
A doughnut or donut is a fried dough food and is popular in many countries and prepared in various forms as a sweet snack that can be homemade or purchased in bakeries, supermarkets, food stalls, and franchised specialty outlets...
-shaped cloud of hot ash and gas (the base surge) sped 100 to 200 mph (160 to 320 km/h) from the base of the column while staying close to the ground, plastering the Ubehebe-facing side of all objects in the area.
Sediments
MioceneMiocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
-aged mostly reddish orange-colored conglomerate
Conglomerate (geology)
A conglomerate is a rock consisting of individual clasts within a finer-grained matrix that have become cemented together. Conglomerates are sedimentary rocks consisting of rounded fragments and are thus differentiated from breccias, which consist of angular clasts...
makes up the exposed bedrock in Ubehebe's walls. These sediment
Sediment
Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....
s were deposited by stream
Stream
A stream is a body of water with a current, confined within a bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as a branch, brook, beck, burn, creek, "crick", gill , kill, lick, rill, river, syke, bayou, rivulet, streamage, wash, run or...
s and contain limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
, mudstone
Mudstone
Mudstone is a fine grained sedimentary rock whose original constituents were clays or muds. Grain size is up to 0.0625 mm with individual grains too small to be distinguished without a microscope. With increased pressure over time the platey clay minerals may become aligned, with the...
, quartzite
Quartzite
Quartzite is a hard metamorphic rock which was originally sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to gray, though quartzites often occur in various shades of pink...
and volcanic cobbles that are up to 8 inches (20 cm) in diameter. There is also a difference in color between these seabed sediments: On the left these sediments are yellowish in hue while on the right they are orange. The reason is due to a fault that separates the two different sedimentary units; over time at least 400 feet (120 m) of vertical displacement along this fault has resulted in the abutment of these two different sedimentary units. Fallout debris dip 30 feet (9 m) over the fault scarp
Fault scarp
A fault scarp is the topographic expression of faulting attributed to the displacement of the land surface by movement along faults. They are exhibited either by differential movement and subsequent erosion along an old inactive geologic fault , or by a movement on a recent active fault...
on the pre-eruption surface but have not been offset by it.
Within Ubehebe small alluvial fan
Alluvial fan
An alluvial fan is a fan-shaped deposit formed where a fast flowing stream flattens, slows, and spreads typically at the exit of a canyon onto a flatter plain. A convergence of neighboring alluvial fans into a single apron of deposits against a slope is called a bajada, or compound alluvial...
s have been built on the crater wall along with talus
Scree
Scree, also called talus, is a term given to an accumulation of broken rock fragments at the base of crags, mountain cliffs, or valley shoulders. Landforms associated with these materials are sometimes called scree slopes or talus piles...
slumps from debris flow
Debris flow
A debris flow is a fast moving, liquefied landslide of unconsolidated, saturated debris that looks like flowing concrete. It is differentiated from a mudflow in terms of the viscosity and textural properties of the flow. Flows can carry material ranging in size from clay to boulders, and may...
s. White silt
Silt
Silt is granular material of a size somewhere between sand and clay whose mineral origin is quartz and feldspar. Silt may occur as a soil or as suspended sediment in a surface water body...
covers the crater bottom of Ubehebe and some surrounding craters.
Visiting
There are three major trails at the crater. One trail goes from the parking area to the bottom of Ubehebe, a second circumnavigates the crater rim, while a third trail leads off to Little Hebe.Wind
Wind
Wind is the flow of gases on a large scale. On Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space...
s at the rim of Ubehebe are very strong and often gust above 50 mph (80 km/h).
See also
- Geology of the Death Valley areaGeology of the Death Valley areaThe exposed geology of the Death Valley area presents a diverse and complex set of at least 23 formations of sedimentary units, two major gaps in the geologic record called unconformities, and at least one distinct set of related formations geologists call groups...
- Racetrack PlayaRacetrack PlayaThe Racetrack Playa, or The Racetrack, is a scenic dry lake feature with "sailing stones" that leave linear "racetrack" imprints. It is located above the northwestern side of Death Valley, in Death Valley National Park, Inyo County, California, U.S.....
- Category: Death Valley
- Category: Protected areas of the Mojave Desert
- Category: Maars of the United States
- Category: Volcanology
- Category: Volcanoes of California