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USGS · 70160102

Renewed inflation of Long Valley Caldera, California (2011 to 2014)

Emily Montgomery-Brown·Charles W. Wicks·Peter F. Cervelli·John O. Langbein·Jerry L. Svarc·David R. Shelly·David P. Hill·Michael Lisowski
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Abstract

Slow inflation began at Long Valley Caldera in late 2011, coinciding with renewed swarm seismicity. Ongoing deformation is concentrated within the caldera. We analyze this deformation using a combination of GPS and InSAR (TerraSAR-X) data processed with a persistent scatterer technique. The extension rate of the dome-crossing baseline during this episode (CA99 to KRAC) is 1 cm/yr, similar to past inflation episodes (1990–1995 and 2002–2003), and about a tenth of the peak rate observed during the 1997 unrest. The current deformation is well modeled by the inflation of a prolate spheroidal magma reservoir ∼7 km beneath the resurgent dome, with a volume change of ∼6 × 10 6  m 3 /yr from 2011.7 through the end of 2014. The current data cannot resolve a second source, which was required to model the 1997 episode. This source appears to be in the same region as previous inflation episodes, suggesting a persistent reservoir.

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Geophysical Research LettersArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 37.07271048132946° to 38.429925130409366° latitude; -119.39117431640625° to -118.24859619140626° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Emily Montgomery-Brown, Charles W. Wicks, Peter F. Cervelli, John O. Langbein, Jerry L. Svarc, David R. Shelly, David P. Hill, Michael Lisowski. 2015-07-07. Renewed inflation of Long Valley Caldera, California (2011 to 2014). https://doi.org/10.1002/2015gl064338

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