mitchell caverns

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Mitchell Caverns Wonder of the Mojave Desert

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Page 1: Mitchell Caverns

Mitchell CavernsWonder of the Mojave Desert

Page 2: Mitchell Caverns

Providence Mountains State

Recreation Area• 100 mi east of Barstow; 60

mi west of Needles• Contains 20 known caves,

including Mitchell Caverns

• 5,900 acres in eastern Mojave Desert

• elevation range: 3,400 - 7,171 ft

Page 3: Mitchell Caverns

Mitchell Caverns• Located at Park headquarters• 4,300 ft with view of

surrounding land• Dimensions

– 300 ft below surface– several hundred ft long

• 65° year round• Only limestone caves in the CA

park system• Electrically lit, paved walkways

Page 4: Mitchell Caverns

The Caverns

• 2 caverns may have been continuous but filled in by calcite deposits

• Passage created in early 70s• Winding Stair Cave also

included in park– Used for practice cave

rescues

• El Pakiva – ‘house of the devil’ or

‘pool of water from the eye of the mountain’

• Tecopa – Legendary Shoshone

chief

Page 5: Mitchell Caverns

What’s the difference between a cave and a cavern, anyway?

According to the National Park Service, not much:

Cave: An underground chamber or cavity created by natural means.

Cavern: A large cave or a cave of indefinite extent. Considered by some cave geologists as

caves formed by solution.

Page 6: Mitchell Caverns

Geologic History

Page 7: Mitchell Caverns

Formation of Caverns

• About 12 Ma:– Area had wetter climate; rainforest– Organic groundcover makes rainwater

acidic– Carbonic acid seeps through ground;

dissolves limestone• Climate change

– Water table lowers– Environment for creating speleothems– Calcite-rich water precipitates when

caverns are not water filled

Page 8: Mitchell Caverns

Rare and Exciting Speleothems

• Coral Pipes– small, cylindrical formations– pebbles allow for erosion into silt pillars– pipes created when travertine deposits on

silt pillars– only found in 8 caves worldwide– rare because flow of water must cease at

critical point

• Cave Shields– 3 ft wide, 1/2 in thick, semicircular sheet of calcite– formed when water seeping in from a crack in the

walls deposits layers of calcite– only found in 60 caves in the US

Page 9: Mitchell Caverns

Fairly Nifty Speleothems

Flowstone (travertine): formed by flowing water.

Cave coral (popcorn): knobby clusters of calcite or aragonite

Stalagmites: formed up from the floor, generally beneath a stalactite.

Helictites: deposit that generally spirals as it grows, seems to defy gravity.

Stalactites: formed on ceilings.

Page 10: Mitchell Caverns

Wanted: Dead or Alive

• Probably last growing significantly at the end of the last Ice Age (10,000 yrs ago)

• Long thought to be ‘dead’• Currently active only during heavy rains• ‘Normal’ growth rate: 1 inch/20 yrs• Mitchell growth rate: 1 inch/10,000 yrs

Page 11: Mitchell Caverns

Cave Life

• Townsend’s bats– relocated after installed passage

created airflow changes– after airlock put in, started to return

• Rare spider beetle• Prehistoric Ground Sloth

– 15,000 yrs old; from Pleistocene time– also fossilized tissue of giant

redwoods, tropical ferns from this time

Page 12: Mitchell Caverns

Chemehuevi Indians

• 500 years• ‘Eyes of the mountain’• Evidence

– cavern walls blackened by smoke– pottery shards, arrowheads, hidden food and tool caches found

• Thought to be used seasonally for shelter and storage• ‘young boys were probably left in the darkness of the caves as part of

a coming-of-age ritual’; ‘came to harvest pinyon nuts in a five-year nomadic cycle’

• Way of life changed with introduction of miners, explorers, etc.• Currently live on reservation by Colorado River

Page 13: Mitchell Caverns

Crystal Cave and Ghost Stories

Jack and Ida Mitchell• Moved to desert

– Early 1930s– Came because of Depression

• Decided to develop caverns commercially– Prospecting silver not profitable

• Improvements to area– Stone buildings, including current park headquarters– Built 23 mi road to caverns

• Explored caverns; stuck in Winding Stair Cave for 2 days• Gave tours of the caverns

– Known for candle lit tours; ghost stories

Page 14: Mitchell Caverns

Birth of a Park

• Park transferred to state 1954• Kept a state entity according to CA

Desert Protection Act of 1994

• By 1950s, Mitchell could no longer care for caverns

• Entered negotiations with CA • Died before negotiations complete

Page 15: Mitchell Caverns

Oliver Stone and Mitchell Caverns?

• Scene from 1991 film “The Doors” shot in the caverns• Controversy over pictographs added to walls

– Couldn’t be removed at first– Hired special team to flush paint out of walls

• Initiated more interest in the caverns

• Other recent events:– Earthquake in October 1999 temporarily destabilized

roof/trail– Reopened 2000

Page 16: Mitchell Caverns