As a seismologist, Haiying Gao studies the properties of the Earth’s crust and mantle using seismic waveforms. A major research focus involves “subduction zones”, the linear belts on Earth where tectonic plates converge, and one plate sinks into the mantle beneath the other plate: Earth’s largest earthquakes and volcanoes tend to occur at these convergent boundaries. Gao relies on high performance computing using resources at the MGHPCC to help her understand the nature of the complex three-dimensional property variations within and along subduction zones.