Subduction Zone Science


When the subducting plate's water-containing rocks reach great enough depths, the high temperatures and pressures enable melting, forming molten magmas and pressurized gases. When these rise to the surface, they may erupt explosively or slowly, spreading lava, ash and gases.

Filter Total Items: 3
Date published: June 30, 2021
Status: Active

U.S. West Coast and Alaska Marine Geohazards

Marine geohazards are sudden and extreme events beneath the ocean that threaten coastal populations. Such underwater hazards include earthquakes, volcanic eruptions, landslides, and tsunamis.

Devastating earthquakes in Japan (2011) and Chile (2010) that spawned pan-oceanic tsunamis sent a sobering reminder that U.S. coastlines are also vulnerable to natural disasters that originate in...

Date published: October 15, 2020
Status: Active

USGS-developed lahar detection systems provide warning of lahars

USGS scientists developed an inexpensive, durable, portable, and easily installed system to detect and continuously monitor the arrival and passage of debris flows and floods in river valleys draining active volcanoes.

Attribution: Natural Hazards
Date published: March 20, 2018
Status: Active


As the 1980 Mount St. Helens eruption showed, volcanoes pose significant threats to U.S. communities. Potential hazards posed by U.S. volcanoes include tephra falls, pyroclastic flows and surges, VOG, ballistic projectiles, lahar and lava flows. In collaboration with researchers from the USGS Volcano Hazards Program, the Hazards Vulnerability Team worked on better understanding and...