Rupture process of the Mw7.0 December 5, 2024 Offshore Cape Mendocino earthquake

Geophysical Research Letters
By: , and 

Links

Abstract

The Mw7.0 December 5, 2024 Offshore Cape Mendocino earthquake ruptured a  km long portion of the east-west trending Mendocino fault zone (MFZ). In order to clarify the rupture process, we assemble three-component seismograms from regional seismic stations, horizontal coseismic displacement vectors derived from Global Navigation Satellite System (GNSS) time series, and a Sentinel-1 ascending interferogram. These data are interpreted with a model of slip distributed on two vertical fault planes representative of the eastern MFZ and spanning the ~70 km length of the aftershock zone. Assuming right-lateral strike slip, we find that the rupture initiates in the oceanic mantle at 20-30 km depth and proceeds unilaterally updip and toward the east. Early aftershocks locate adjacent to the peak slip areas, tracking the coseismic rupture propagation from oceanic mantle to shallower depth and implying a significant role of static stress transfer in driving aftershocks in an ocean plate environment.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Rupture process of the Mw7.0 December 5, 2024 Offshore Cape Mendocino earthquake
Series title Geophysical Research Letters
DOI 10.1029/2025GL115613
Volume 52
Issue 14
Publication Date July 24, 2025
Year Published 2025
Language English
Publisher American Geophysical Union
Contributing office(s) Earthquake Science Center
Description e2025GL115613, 10 p.
Country United States
State California
Other Geospatial Offshore Cape Mendocino
Additional publication details