Long Valley Caldera 2003 through 2014: Overview of low level unrest in the past decade

Stuart K. Wilkinson; David P. Hill; John O. Langbein; Michael Lisowski; Margaret T. Mangan

doi:10.3133/ofr20141222

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Long Valley Caldera 2003 through 2014: Overview of low level unrest in the past decade

Stuart K. Wilkinson·David P. Hill·John O. Langbein·Michael Lisowski·Margaret T. Mangan

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Abstract

Long Valley Caldera is located in California along the eastern escarpment of the Sierra Nevada Range. The caldera formed about 760,000 years ago as the eruption of 600 km 3 of rhyolite magma (Bishop Tuff) resulted in collapse of the partially evacuated magma chamber. Resurgent doming in the central part of the caldera occurred shortly afterwards, and the most recent eruptions inside the caldera occurred about 50,000 years ago. The caldera remains thermally active, with many hot springs and fumaroles, and has had significant deformation and seismicity since at least 1978. Periods of intense unrest in the 1980s to early 2000s are well documented in the literature (Hill and others, 2002; Ewert and others, 2010). In this poster, we extend the timeline forward, documenting seismicity and deformation over the past decade.

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Source-reported bounding extent: 37° to 38.75° latitude; -120° to -118° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Stuart K. Wilkinson, David P. Hill, John O. Langbein, Michael Lisowski, Margaret T. Mangan. 2014. Long Valley Caldera 2003 through 2014: Overview of low level unrest in the past decade. https://doi.org/10.3133/ofr20141222

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