Speaker: Associate Professor Brandon Schmandt from the University of New Mexico

Title: "Investigating Mount St. Helen seismicity and magma plumbing with hybird passive and active seismic arrays"

Abstract: Starting in 2014 seismologists from several universities (U. Washington, Rice U., Cornell U., UNM) and the USGS teamed up to deploy multi-scale broadband and short-period seismic arrays to seismically image the structure beneath Mount St. Helens and detect diverse seismogenic processes underlying the volcano. An unusual aspect of the dense array of short-period seismometers is that it recorded continuously to study local earthquakes in addition to obtaining dense recordings of controlled source explosions. Emerging results from the collaborative study include high-resolution detection and location of multiple types of earthquakes spanning most of the crustal column, and evidence for multi-stage magma ascent starting with input of mantle melts into the lower crust offset to the east of Mount St. Helens.

Bio: Brandon conduct research in geophysics, primarily using the tools of seismology to study Earth's structure and surface or subsurface processes that make seismic signals. The questions that drive my research are often related to links between tectonic and volcanic processes apparent at the surface and underlying mantle convection and deep crustal deformation. My other active research interests include using seismology to investigate the bulk and volatile composition of the scarcely sampled deep Earth and improving the utility of seismology for continuously tracking mechanical surface processes such as sediment transport in rivers.