Mono-Inyo Craters

The Long Valley Caldera (outlined in red) with the Inyo Craters (brown circles in the west of the Caldera ) and the Mono Craters to the north

Panum Crater with central lava dome (Mono Craters).

The Mono Craters and Inyo Craters , also known collectively as Mono-Inyo Craters , form an approximately 30 km long chain of volcanic ash cones , lava domes and lava flows in the central east of the US state of California between Mono Lake in the north and the Long Valley Caldera in the South. Some of the Inyo Craters are also located within the caldera .

The formation of the Mono-Inyo Craters are the most recent eruptions of the Long Valley volcanic system. In particular, the porphyry rocks of the Inyo Craters, due to their chemical composition, indicate that part of the melt originated from the magma system of the Long Valley Caldera, but an independent source also appears to be involved. The Mono-Inyo Craters were formed around 600 years ago when an igneous duct along a north-south system of tectonic faults penetrated the earth's surface. The last eruptions of the Mono Craters have been dated to a period between 1325 and 1365 AD using dendrochronology and the radiocarbon method . During this period, 0.6 km³ of magma was ejected from this, 2/3 of it in the form of lava and 1/3 as volcanic ash .

Due to the high SiO ₂ content of the rock melt and the resulting high viscosity of the lavas, a large part of the erupted material solidified in the form of rhyolite obsidian as dome (domes), which only pushed up out of the volcanic vent without actually flowing. This also happened in part within the craters of previous eruptions, such as at Panum Crater, the northernmost crater of the volcanic chain. The area is extensively covered by a layer of tephra that originated from the explosive periods of the Mono-Inyo Craters .

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↑ Sampson DE & Cameron KL (1987): The geochemistry of the Inyo volcanic chain: multiple magma systems in the Long Valley region, eastern California. In: Journal of Geophysical Research . Vol. 92 no. B10, pp. 403-421.
↑ See K. & Bursik M. (1986): Most recent eruption of the Mono Craters, eastern central California. In: Journal of Geophysical Research . Vol. 91 No. B12, pp. 539-571.

Web links

Commons : Mono-Inyo Craters - collection of images, videos and audio files

US Geological Society: Mono Inyo Craters
Mono Craters in the Global Volcanism Program of the Smithsonian Institution (English)
Inyo Craters in the Global Volcanism Program of the Smithsonian Institution (English)

37.883333333333 -119 2796Coordinates: 37 ° 53 ′ N , 119 ° 0 ′ W

[1] Sampson DE & Cameron KL (1987): The geochemistry of the Inyo volcanic chain: multiple magma systems in the Long Valley region, eastern California. In: Journal of Geophysical Research . Vol. 92 no. B10, pp. 403-421.

[2] See K. & Bursik M. (1986): Most recent eruption of the Mono Craters, eastern central California. In: Journal of Geophysical Research . Vol. 91 No. B12, pp. 539-571.