Mammoth Mountain
Mammoth Mountain from Hwy395
Elevation	11,059 feet (3,371 metres)
Location	California, USA
Range	Sierra Nevada
Coordinates	37°37′50.26″N, 119°1′57.45″W
Topo map	USGS Mammoth Mountain
Type	lava dome complex
Age of rock	50,000-200,000 years
Last eruption	~1400 AD
Easiest route	gondola

Mammoth Mountain is a large lava dome complex^[1] that lies to the west of the town of Mammoth Lakes, California in the Inyo National Forest. US Route 395 is a US Route in the western United States. The southern terminus of the route is in the Mojave Desert at Interstate 15 near In topography a summit is a point on a surface which is higher in Elevation than all points immediately adjacent to California ( is a US state on the West Coast of the United States, along the Pacific Ocean. The United States of America —commonly referred to as the A mountain range is a chain of Mountains bordered by highlands or separated from other mountains by passes or valleys The Sierra Nevada ( Spanish for "Snowy Range" is a Mountain range located in the U A geographic coordinate system enables every location on the Earth to be specified in three coordinates using mainly a spherical coordinate system. A topographic map is a type of Map characterized by large-scale detail and quantitative representation of relief, usually using Contour lines in modern The United States Geological Survey ( USGS) is a scientific agency of the United States government. Mountains can be characterized in several ways Some mountains are Volcanoes and can be characterized by the type of lava and eruptive history The geologic time scale is a chronologic schema (or idealized Model) relating Stratigraphy to time that is used by Geologists and other Plate tectonics and hotspots Divergent plate boundaries At the A climbing route is a path by which a climber reaches the top of a Mountain, rock or ice wall In Volcanology, a lava dome or plug dome is a roughly circular Mound -shaped protrusion resulting from the slow eruption of Felsic Lava Mammoth Lakes is an incorporated town in Mono County, California, United States. Inyo National Forest is a federally protected Forest in the United States.

Mammoth Mountain is home to the Mammoth Mountain Ski Area which is notable in that it gets an unusually large amount of snow compared to other Eastern Sierra peaks, due to Mammoth Mountain lying in a low gap in the Sierra crest. The Mammoth Mountain Ski Area is a large Ski resort located in eastern California on the east side of the Sierra Nevada mountain range in the The Sierra Nevada ( Spanish for "Snowy Range" is a Mountain range located in the U ^[2] In the summer months the ski gondolas are used by mountain bikers and tourists who wish to get a spectacular summit view of Long Valley Caldera directly to the east and Sierra peaks to the west, south and north. A Gondola is a traditional Venetian rowing Boat. Gondolas were for centuries the chief means of transportation within Venice and still have Mountain biking entails the Sport of riding Bicycles off-road often over rough terrain whether riding specially equipped Mountain bikes or hybrid road bikes For the town in New Jersey see Long Valley New Jersey Long Valley Caldera is a depression in Eastern California that is adjacent to

Geological origins

The mountain was formed from a long series of eruptions that started about 110,000 years ago and lasted to perhaps 50,000 years ago, although the volcano is still active with minor eruptions; the largest of which was a minor phreatic (steam) eruption 600 years ago. The term phreatic is used in Earth sciences to refer to matters relating to ground water below the static Water table (the word originates from the Greek Mammoth Mountain is composed primarily of dacite and rhyolite; some of which have been altered by hydrothermal activity from fumaroles (steam vents). Dacite ( deɪsaɪt) is an igneous, volcanic rock with a high iron content This page is about a volcanic rock For the ghost town see Rhyolite Nevada, and for the satellite system see Rhyolite/Aquacade. Hydrothermal circulation in its most general sense is the circulation of hot water 'hydros' in the Greek meaning water and 'thermos' meaning heat Mammoth lies on the South end of the Mono-Inyo chain of volcanic craters, some of which erupted as recently as 250 years ago. Mono-Inyo Craters in California USA are a nearly straight line of small Volcanoes that stretch from Mammoth Mountain and Long Valley Caldera A volcanic crater is a circular depression in the ground caused by volcanic activity

Mammoth Mountain is on the southwestern edge of Long Valley Caldera, a large area that subsided after an enormous eruption 760,000 years ago. In fact the same magma chamber that was the source of the heat that eventually caused this great eruption also feeds Mammoth Mountain through fissures at the edge of the caldera. A magma chamber is a large underground pool of molten rock lying under the surface of the earth's crust

Mammoth Mountain from the north (Minaret Summit)

CO₂ Discharge

Mammoth is outgassing large amounts of carbon dioxide out of its South flank, near Horseshoe Lake. Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single The concentration of carbon dioxide in the ground reaches over 50%. Measurements of the total discharge of carbon dioxide gas at the Horseshoe Lake tree kill area range from 50-150 tons per day. This high concentration causes trees to die in six regions that total about 170 acres (0. 688 km²) in size (see photo, below). Camping has been prohibited in the tree kill area since 1995, to prevent asphyxiation of campers due to accumulation of carbon dioxide in tents and restrooms. ^[3]

The tree kills originally were attributed to a severe drought that affected California in the late 1980s and early 1990s. Another idea was that the kills were the result of a pathogen or other biological infestation. A pathogen (from Greek πάθος pathos "suffering passion" and γἰγνομαι (γεν- gignomai (gen- "I give birth to" infectious However neither idea explained why all trees in the affected areas were killed regardless of age or health. Then in March 1990, a United States Forest Service ranger became ill with suffocation symptoms after being in a snow-covered cabin near Horseshoe Lake. Doctors later determined the cause: carbon dioxide poisoning. Hypercapnia or hypercapnea (from the Greek hyper = "above" and kapnos = " Smoke " also known as hypercarbia is

Carbon dioxide has killed a large area of trees

Measurements around the lake found that restrooms and tents had a greater than 1% CO₂ concentration (toxic), and a deadly 25% concentration of CO₂ in a small cabin. A tent is a shelter consisting of sheets of fabric or other material draped over or attached to a frame of poles or attached to a supporting rope CO₂ concentrations of less than 1% are typical and healthy in most soils, however soil concentrations of CO₂ in the tree kill areas ranged from 20% to 90%. Soil, often typeset as SOiL, is a four piece rock band from Chicago Illinois United States founded by Shaun Glass Tom Schofield Tim King and Adam Zadel This overabundance of CO₂ was found to be the cause of the tree kills because tree roots need to absorb O₂ directly and the high CO₂ level reduced available O₂. Researchers also determined that Mammoth releases about 1,300 tons of CO₂ every day. As of 2003 the concentration of carbon dioxide in soil gas at Mammoth Mountain is being monitored on a continuous, year-round basis at four sites - three at Horseshoe Lake and one near the base of Chair 19 at the ski area. Year 2003 ( MMIII) was a Common year starting on Wednesday of the Gregorian calendar.

Mammoth Mountain from the east

The most likely sources of the CO₂ are degassing of intruded magma and gas release from limestone-rich metasedimentary rocks that are heated by magmatic intrusions. Magma (Plurals magmas and magmata) is molten rock that sometimes forms beneath the surface of the Earth (or any other Terrestrial planet Limestone is a Sedimentary rock composed largely of the Mineral Calcite ( Calcium carbonate: CaCO3 In Geology, metasediment is Sediment or Sedimentary rock that shows evidence of having been subjected to Metamorphism. The remarkable uniformity in chemical and isotopic composition of the CO₂ and accompanying gases at different locations around Mammoth Mountain indicates that there may actually be a large reservoir of gas deep below the mountain from which gas escapes along faults to the surface. Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides In Geology a fault, or fault line, is a planar rock fracture which shows evidence of relative movement ^[3]

On April 6, 2006, three ski patrollers at the ski area perished due to a combination of CO₂ and hydrogen sulfide (H₂S) poisoning. Events 46 BC - Julius Caesar defeats Caecilius Metellus Scipio and Marcus Porcius Cato in the Battle of Thapsus Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. ^[4] Both gases are present on a known dangerous fumarole on the mountain and were more concentrated on that day because the fumarole had been covered by snow for days. Four patrollers, including John "Scott" McAndrews and James Juarez, were raising the fence around the fumarole, which had become buried due to heavy snowfall. The fumarole had melted a cavern below the snowbridge which collapsed under James and Scott. For another meaning see Avalanche snow bridge Snow bridge is an arc across a Crevasse, a crack in rock a Creek, or some other The pair fell 21 feet, went into convulsions and died in a matter of minutes. Another ski patroller, Walt Rosenthal, perished and seven others were injured trying to rescue James and Scott. Unfortunately, the only type of oxygen mask used by Mammoth Mountain was of the kind that does not completely seal outer gases from coming in. ^[4]

The view from Dry Creek.

References

External links

• Mammoth Mountain Ski Area trail map
• USGS Volcano Hazards Program, Long Valley Observatory
• QTVR of tree kill area
• A website dedicated to James Juarez

• Mammoth Mountain is at coordinates 37°37′50″N 119°01′57″W / 37.63063, -119.03262 (Mammoth Mountain)Coordinates: 37°37′50″N 119°01′57″W / 37.63063, -119.03262 (Mammoth Mountain)