Volcanoes of the Mojave: The 2022 Desert Symposium field trip road log

David C. Buesch; David M. Miller; Bruce Bridenbecker; Mark Sweeney

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USGS · 70236543

Volcanoes of the Mojave: The 2022 Desert Symposium field trip road log

David C. Buesch·David M. Miller·Bruce Bridenbecker·Mark Sweeney

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Abstract

Basalt lava fields, some decorated with scoria ‘cinder’ cones, are scattered around the Mojave Desert. Most basalt fields are short-lived, but the Cima volcanic field is unique in having eruptions that span ~7.5 m.y., including the youngest eruption in the Mojave Desert at ~12 ka. Xenolith-bearing basalts that include both mantle and deep crustal rocks are known in several fields. All basalt fields except Cima are restricted to the active eastern California shear zone, and many lie directly on active faults, indicating a direct relation between faults and volcanism. The field trip will visit the Pisgah, Dish Hill, Amboy, Cima, and Bicycle Lake volcanic fields, and it will enable examination of the physical volcanology in the basalt fields, including the types of eruptions (effusive and explosive) and the resulting deposits (lava flows, scoria cones, and tuff cones). It will also review the petrology, paleomagnetism, remote sensing, and planetary geology studies conducted at each volcanic field, and how these studies influenced the development of each of these study areas.

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Source-reported bounding extent: 34.63772760271713° to 35.3308118573182° latitude; -116.19140625° to -115.400390625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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David C. Buesch, David M. Miller, Bruce Bridenbecker, Mark Sweeney. 2022. Volcanoes of the Mojave: The 2022 Desert Symposium field trip road log. https://pubs.usgs.gov/publication/70236543

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