Jump to content

Fish Canyon Tuff

Coordinates: 37°45′23″N 106°56′03″W / 37.75639°N 106.93417°W / 37.75639; -106.93417
From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by GeoWriter (talk | contribs) at 16:11, 7 August 2015 (added category "Volcanism of Colorado"). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

The Fish Canyon Tuff ignimbrite

The Fish Canyon Tuff is the large volcanic ash flow deposit resulting from one of the largest known explosive eruptions on Earth, estimated at 5,000 cubic kilometers.[1] (see List of largest volcanic eruptions) The eruption was centered at La Garita Caldera in southwest Colorado. The tuff can be assured to belong to one eruption due to its high chemical consistency (SiO2=bulk 67.5-68.5% (dacite), matrix 75-76% (rhyolite) and consistent phenocryst content (35-50%) and composition (plagioclase, sanidine, quartz, biotite, hornblende, sphene, apatite, zircon, Fe-Ti oxides are the primary phenocrysts). This tuff and eruption is part of the larger San Juan volcanic field and Mid-Tertiary ignimbrite flare-up.

References

  1. ^ Ort, Michael. "Largest explosive eruptions:". Retrieved 14 August 2010.

37°45′23″N 106°56′03″W / 37.75639°N 106.93417°W / 37.75639; -106.93417