A subduction zone in pieces: the segmented Cascadia megathrust

Onshore and offshore seismic data informs researchers working on megathrust boundaries, improving our understanding of where subduction zone earthquakes might occur and why.

Quaking beneath the ice

The geology of East Antarctica lies hidden below many kilometers of ice, and presents a fascinating and complex problem for geologists. Historically, very few earthquakes have been recorded in Antarctica but data from a new seismic array has allowed scientists to detect earthquakes below the ice, and their results directly contradict the notion that Antarctica is seismically and tectonically inactive.

Tiny Northwest Quakes Tied to Deep-Crust Structure

Rice University researchers found a strong correlation exists between tremor density and underthrusting sediments at the Cascadia margin off the Pacific Northwest’s coast. Fluids that are released from the downgoing slab are concentrated in these sediments and lead to very slow seismic velocities in the region.