geo.wikisort.org - Mountains

Mount Hannah is a mountain in the Mayacamas Mountains of the Northern California Coast Ranges. It is in Lake County, California.

Mount Hannah
Mount Hannah Location in California
Highest point
Elevation	3,978 feet (1,212 m)
Prominence	1,338 feet (408 m)
Isolation	7.94 kilometres (4.93 mi) to Cobb Mountain
Coordinates	38.887258°N 122.746296°W / 38.887258; -122.746296
Geography
Country	United States
State	Caligornia
County	Lake County

Location

Mount Hannah is in Lake County, California.[1] It is one of the mountains in the Cobb Mountain Area, many of which have volcanic origin. Others are Cobb Mountain, the most dominant, Seigler Mountain and Boggs Mountain. There are isolated small valleys and basins between the mountain peaks.[2]

Mount Hannah has an elevation of 3,692 feet (1,125 m). Clean prominence is 1,338 feet (408 m). Isolation is 7.94 kilometres (4.93 mi). The nearest higher neighbor is Cobb Mountain to the south.[1]

Geology

Mount Hannah formed quite quickly during a polarity transition.[3] It was built up by a number of closely-spaced eruptions.[4] Three of the dacites in the Mount Hannah sequence have been dated to between 0.90 and 0.92 million years ago.[3] There are indications that there may be a crustal magma chamber about 10–15 kilometres (6.2–9.3 mi) in diameter and a depth of 15 kilometres (9.3 mi) below Mount Hannah, with a temperature above 550 °C (1,022 °F).[5]

Notes

Sources

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