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Posts by Matthew E. Pritchard

v13n1 Supplement Biggs and Pritchard

Back to Main Article Volcano Deformation Data (1900-2016) compiled by Juliet Biggs and Matthew Pritchard. Supplement to the February 2017 (v13n1) issue of Elements. Disclaimer: this table was not reviewed by Elements nor was the contents verified. NOTES: The table does not include anthropogenic deformation (e.g., related to pumping at geothermal power plants). Deformation magnitudes indicate…

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Global Volcano Monitoring: What Does it Mean When Volcanoes Deform?

Currently, it is only possible to look inside an active volcano using indirect geophysical methods. One such method is to measure surface deformation, which results from subsurface magmatic or hydrothermal processes. Modern satellite data allows deformation to be measured at hundreds of volcanoes without relying on limited ground instrumentation. As a result, the number of known deforming volcanoes has increased from 44 in 1997 to over 220 in 2016. This article reviews the diverse ways by which volcanoes can deform, the typical rates and durations of such deformations, and the processes that drive deformation.

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Geophysical Evidence for Silicic Crustal Melt in the Continents: Where, What Kind, and How Much?

The accumulation of sizeable volumes of magma in the upper crust may produce plutons and/or result in supereruptions. Geophysical observations provide constraints on the rates, volumes, and melt distributions in magmatic systems, but they suffer from limited resolution and inherent nonuniqueness. Different, yet complementary, geophysical approaches must be combined with petrological, laboratory, and geochemical measurements. We summarize the results from such a combined approach from the central Andes. Taking a global perspective on large silicic systems reveals that several have >10% partial melt over large areas (10s of km2), and there may be localized zones with 50% or more.

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