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Volcanic history of Mount Konocti

Mount Konocti is a 1,312 m (4,305 ft) mountain that dominates the view of the eastern shore of Clear Lake.

Mount Konocti on the western shore of Clear Lake, California
Mount Konocti, a mostly dacitic lava dome complex, on the western shore of Clear Lake, California. 

This lava dome complex began forming its major edifice approximately 350,000 years ago, though core samples have been dated to 480,000 years ago. Dacites from these early dome-forming eruptions vented in a west- northwest-trending zone, which culminated at the northwest end of the Mount Konocti edifice. This mountain contains the largest volume of dacite in the Clear Lake Volcanic Field and must have been fed from a sizeable magma chamber.

While much of Mount Konocti is made up of dacite lava, Buckingham Peak also hosts basaltic andesite lavas similar to young basaltic andesite scoria cones elsewhere in the Clear Lake Volcanic Field. These lavas sit atop the dacite domes and represent the youngest eruptions on Konocti, though they are as yet undated.

The blocky surface of Konocti's lava domes host many talus caves, and in places air flow from these caves gives the impression of a 'breathing' mountain. The flanks are also cut by several landslide, including the Black Forest landslide to the north-northeast. This landslide, which cuts into Buckingham Peak, predates at least some of the phreatomagmatic eruptions, as the Little Borax Lake maar cuts through existing landslide deposits.