Английская Википедия:Hole-in-the-Ground

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Шаблон:Short description Шаблон:About Шаблон:Infobox mountain Hole-in-the-Ground is a large maar (volcanic explosion crater) in the Fort Rock–Christmas Lake Valley basin of Lake County, central Oregon, northeast of Crater Lake, near Oregon Route 31.[1]

It is about Шаблон:Convert across, a little longer N-S than E-W.[1] Its floor is about Шаблон:Convert below the surrounding ground level and has a rim that rises Шаблон:Convert above, the highest point on the east side. The crater formed during the late Pleistocene, between 13,500 and 18,000 years ago, at which time the Fort Rock basin was a lake and the location was near the shore. Basaltic magma intruding near the surface flashed ground water to steam, which blew out overlying rock and soil, along with some juvenile material. As material slid into the hole formed, it closed the vent and the process repeated, eventually forming the huge hole.[2] Blocks as large as Шаблон:Convert in size were flung as far as Шаблон:Convert from the crater.[3]

To the west of Hole-in-the-Ground is an even bigger maar, Шаблон:Convert, but older and more eroded, called Big Hole.

Шаблон:Wide image

See also

References

Шаблон:Reflist

Шаблон:Volcanoes of Oregon


Шаблон:US-geology-stub