Relation of mineralization to calderas in the San Juan volcanic field, southwestern Colorado

Thomas A. Steven; Robert G. Luedke; Peter W. Lipman

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Relation of mineralization to calderas in the San Juan volcanic field, southwestern Colorado

Thomas A. Steven·Robert G. Luedke·Peter W. Lipman

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Abstract

A review of the calderas in the San Juan volcanic field, southwestern Colorado, indicates that lead, zinc, copper, gold, and silver mineralization took place in and near calderas which had complex histories of postsubsidence intrusive and extrusive igneous activity. Most known ore occurs in veins that follow fractures formed during the different caldera cycles, but some intrusive bodies were extensively mineralized and possibly may host disseminated, porphyry-type deposits. The mineral deposits seem to be related most commonly to the youngest and most highly differentiated late intrusives of a caldera cycle.

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Journal of Research of the U.S. Geological Survey Article

Source-reported bounding extent: 37.01132594307015° to 39.232253141714885° latitude; -108.424072265625° to -105.655517578125° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Thomas A. Steven, Robert G. Luedke, Peter W. Lipman. 1974. Relation of mineralization to calderas in the San Juan volcanic field, southwestern Colorado. https://pubs.usgs.gov/publication/70232457

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