Английская Википедия:El Salvador (caldera)

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El Salvador is a caldera in Chile.

The mountains La Antena and Contreras form the southeastern margin of the caldera, while the Шаблон:Convert high Cerro Indio Muerto massif lies inside the caldera.Шаблон:Sfn

The terrain around the caldera is formed by a Paleozoic basement, Mesozoic sedimentary rocks and also Mesozoic volcanic rocks; the latter are separated from the first two units by branches of the Domeyko fault system;Шаблон:Sfn this fault system and its branches have controlled the emplacement of a large number of copper deposits.Шаблон:Sfn Later sequences include the Miocene Atacama gravels and Quaternary alluvium.Шаблон:Sfn

The Paleocene volcanism is characterized by trachyandesite and trachybasalt, which define a potassium-rich calc-alkaline suite. Phenocrysts include biotite, clinopyroxene and olivine.Шаблон:Sfn Eocene rocks are also calc-alkaline, but they contain less potassium and contain phenocrysts of biotite and hornblende.Шаблон:Sfn

El Salvador during the Paleocene collapsed and erupted the Cerros Contreras-La Antena ignimbrites. Later the Indio Muerto lava dome complex was emplaced in the northeastern part of the caldera, while a lava-ignimbrite sequence known as the Los Amarillos-Kilómetro Catorce developed in the eastern part of the caldera.Шаблон:Sfn The history of the volcanic complex was at first considered to be continuous, but later it was found that it involved a Paleocene and an Eocene phase,Шаблон:Sfn with caldera formation occurring about 63-61 million years ago.Шаблон:Sfn The Eocene volcanic episode appears to be unrelated to the Paleocene one and gave rise to ore deposits.Шаблон:Sfn

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