A hidden chunk of an ancient tectonic plate is stuck to the Pacific Ocean floor and sliding under North America, complicating ...

By tracking swarms of very small earthquakes, seismologists are getting a new picture of the complex region where the San Andreas fault meets the Cascadia subduction zone, an area that could give rise ...

Researchers have identified an ancient tectonic fragment, the Pioneer fragment, buried under the coast, which may exacerbate earthquake hazards associated with the San Andreas and Cascadia faults.

Invisible earthquakes are revealing a hidden tectonic puzzle beneath California’s most dangerous fault zone.

Northern California’s coast keeps you on alert, even on quiet days. Offshore, three tectonic plates meet near Humboldt County ...

Tiny earthquakes have revealed potentially deadly hidden faults beneath California. By tracking swarms of very small tremors, ...

Learn about the movement of tectonic plates off the coast of northern California, a process that could incite major ...

Scientists are uncovering a hidden and surprisingly complex earthquake zone beneath Northern California by tracking swarms of ...

A hidden shard of ancient crust has been detected where California’s San Andreas system collides with the Cascadia subduction ...

Memorizing seven continents feels settled, like learning the alphabet. A new study argues the ground rules are less tidy.

Beneath the quiet plains and bustling cities of the U.S. and Canada, an ancient process is slowly playing out. According to a new study published in Nature Geoscience, pieces of North America's oldest ...