Reflections on the Accomplishments of EarthScope’s USArray

The USArray has operated for over 15 years as a community science facility designed to address EarthScope’s goal of understanding the structure and evolution of the North American continent. Continue Reading

IRIS PASSCAL to Expand Pool of Seismic Instruments

IRIS has begun the procurement of 460 Fairfield nodes for general PASSCAL pool use. The new nodes should be ready for general usage starting in February 2019 (bringing the general node pool to 533 units). Continue Reading

USArray in the news!

USArray Transportable Array science featured in exciting Accuweather video special feature! Continue Reading


Apr 11 Educators - Learn about Earthquakes at NSTA St. Louis
Apr 17 2019 Spring BoD Meetings Washington, DC
Jul 16 IRIS/SSA Distinguished Lectureship Series Oregon Museum of Science and Industry, Empirical Theater (Portland,Oregon)
Nov 13 2019 Fall BoD Meetings Fort Collins, Colorado
Earthquake Resources

NEW ANIMATION! Foreshock, mainshock or aftershock?

Large earthquakes are usually followed by hundreds and even thousands of smaller earthquakes, called aftershocks. In some earthquake sequences, a smaller earthquake called a “foreshock”, precedes the mainshock.

¡Animación de la tectónica de placas ahora en español!

Placas Tectónicas: ¿Que son las Placas (litosféricas) tectónicas?

A subduction zone in pieces: the segmented Cascadia megathrust

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

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

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.