David R. Shelly David P. Hill Andrew M. Pitt Phillip B. Dawson Bernard A. Chouet Alicia J. Hotovec-Ellis 2018 <p><span>Although most volcanic seismicity is shallow (within several kilometers of the surface), some volcanoes exhibit deeper seismicity (10 to 30+ km) that may reflect active processes such as magma resupply and volatile transfer. One such volcano is Mammoth Mountain, California, which has also recently exhibited high rates of CO</span>₂<span>&nbsp;discharge at the surface. We perform high-resolution earthquake detection and relocation to reveal punctuated episodes of rapidly propagating seismicity at mid-crustal depths along a narrow fracture zone surrounding a body of partial melt. We infer that these earthquakes track dike intrusions or fluid pressure pulses associated with CO</span>₂<span>&nbsp;exsolution, suggesting that the deep plumbing system of Mammoth Mountain is an active conduit for fluid transport from the base of the crust to the surface.</span></p> application/pdf 10.1126/sciadv.aat5258 en American Association for the Advancement of Science Deep fluid pathways beneath Mammoth Mountain, California, illuminated by migrating earthquake swarms article