[1] Ground surface tilts recorded proximal to a growing lava dome, and sustained through repeated dome collapses, provide unique geodetic constraints on the depth, size, and overpressures of the shallow magmatic system at Soufrière Hills Volcano. Tilt records identify a single pressure-source inflating with periods 3–30 h. Sustained tilt amplitude ratios for paired stations identify the pressur...

In the search for evidence of the environmental history of the Martian surface, and the possibility of life at some stage in the planet’s history, a key component is reduced carbon. Carbon is available to the surface environment through meteoritic infall [1] and erosion of abundant volcanic rocks which contain magmatic carbon [2][3], in addition to the possibility of some biogenic carbonaceous ...

An understanding of the formation of large magmatic reservoirs is a key issue for the evaluation of possible strong volcanic eruptions in the future. We estimated the size and level of maturity of one of the largest volcanic reservoirs, based on radial seismic anisotropy. We used ambient-noise seismic tomography below the Toba caldera (in northern Sumatra) to observe the anisotropy that we inte...

The Yellowstone supervolcano is one of the largest active continental silicic volcanic fields in the world. An understanding of its properties is key to enhancing our knowledge of volcanic mechanisms and corresponding risk. Using a joint local and teleseismic earthquake P-wave seismic inversion, we revealed a basaltic lower-crustal magma body that provides a magmatic link between the Yellowston...

Subsurface waters have been classified into meteoric water, ocean water, evolved connate water, magmatic water and juvenile water. Geothermal water is mostly meteoric and oceanic water although andesitic waters near subduction areas often contain significant proportions of evolved connate and magmatic waters. Geothermal waters have been classified with respect to their anion and cation contents...

We review here three main (first-order) mechanisms of stress variation able to influence the triggering of volcanic eruptions and the possible impact on eruption dynamics. They are shortand long-term unloading, seismic energy effects, and changes in far field stress due to geodynamic processes. We present an equilibrium equation for rupture of magma chamber and opening of a dyke up to the surfa...

The Yellowstone supervolcano is one of the largest active continental silicic volcanic fields in the world. An understanding of its properties is key to enhancing our knowledge of volcanic mechanisms and corresponding risk. Using a joint local and teleseismic earthquake P-wave seismic inversion, we revealed a basaltic lower-crustal magma body that provides a magmatic link between the Yellowston...

Gravitational lithosphere removal in continental interior has been inferred from various observations, including anomalous surface deflections and magmatism. We use numerical models and a simplified theoretical analysis to investigate how lithosphere removal can be recognized in the magmatic record. One style of removal is a Rayleigh-Taylor-type instability, where removal occurs through drippin...