1872 Lone Pine earthquake
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The Great Lone Pine earthquake was one of the largest earthquakes to hit California in recorded history. The quake struck on March 26, 1872 and its epicenter was near Lone Pine, California in Owens Valley. The true size of this earthquake is not known, but historical evidence detailing the damage it caused in settlements and landforms near the epicenter and the geographic extent to which noticeable movement was felt, leads researchers to estimate a Richter magnitude of 7.6 to 8 or greater - similar in size to the 1906 San Francisco earthquake.
The quake hit at 2:35 in the morning and leveled almost all the buildings in Lone Pine and nearby settlements. Of the estimated 250-300 inhabitants of Lone Pine, 27 are known to have perished and 52 of the 59 houses were destroyed. One report states that the main buildings were thrown down in almost every town in Inyo County. About 100 kilometers south of Lone Pine, at Indian Wells, California, adobe houses sustained cracks. Property loss has been estimated at $250,000 (1872 dollars). As in many earthquakes, adobe, stone and masonry structures fared worse than wooden ones which prompted the closing of nearby Camp Independence which was an adobe structure destroyed in the quake.
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The quake was felt strongly as far away as Sacramento where citizens were startled out of bed and into the streets. Giant rockslides in what is now Yosemite National Park woke naturalist John Muir, then living in Yosemite Valley, who reportedly ran out of his cabin shouting, "A noble earthquake!" and promptly made a moonlit survey of the fresh talus piles. This earthquake stopped clocks and awakened people in San Diego, California to the south, Red Bluff, California to the north, and Elko, Nevada, to the east. The shock was felt over most of California and much of Nevada. Thousands of aftershocks occurred, some severe.
The quake resulted from sudden vertical (15-20 feet) and right-lateral (35-40 feet) movement on the Lone Pine fault and part of the Owens Valley fault. These faults are part of a twin system of normal faults that run along the base of two parallel mountain ranges; the Sierra Nevada on the west and Inyo Mountains on the east flank of Owens Valley. This particular event created fault scarps from north of Big Pine, California (55 miles north of Lone Pine), to Haiwee Reservoir (30 miles south of Lone Pine).
Researchers later estimated that similar earthquakes occur on the Lone Pine fault every 3,000-4,000 years. However, the Lone Pine fault is only one of many faults on two parallel systems of faults mentioned above.
This earthquake also reportedly formed a small graben that later was filled by Diaz Lake.
Many geoscientists who have studied the area, theorize that quakes similar to the 1872 Lone Pine event, are responsible for creating Owens Valley (see Basin and Range Province for ideas on what triggers these quakes).
Reference
- Geology Underfoot in Death Valley and Owens Valley, Sharp, Glazner (Mountain Press Publishing Company, Missoula; 1997) ISBN 0-87842-362-1
- USGS web page about the 1872 Lone Pine earthquake (http://neic.usgs.gov/neis/eq_depot/usa/1872_03_26.html)