On October 17, 1989, at 5:04:15 p.m. (PDT), a magnitude 6.9 earthquake severely shook the San Francisco and Monterey Bay regions. The epicenter was located near Loma Prieta peak in the Santa Cruz Mountains, approximately 14 km (9 mi) northeast of Santa Cruz and 96 km (60 mi) south-southeast of San Francisco.
Progress Towards a Safer Future Since the 1989 Loma Prieta Earthquake
Earthquakes remain an ongoing threat to the San Francisco Bay region. This USGS Factsheet examines earthquake hazards in the region, including probabilities, preparedness, and communicating hazards.
Ground Shaking Animations
To better understand the distribution of shaking from past and anticipated future earthquakes, seismologists have constructed computer models of earthquakes and the resulting ground shaking. This movie shows shaking intensity as the seismic waves travel away from the earthquake epicenter over time.
Map showing ground motion and shaking intensity based on instrumental
measurements of shaking along with information about local geology and the
earthquake’s location and magnitude.
Did You Feel It?
Map of shaking intensity based on 15,000+ reports from citizens who experienced the
USGS Photos of Loma Prieta Earthquake Damage
More than 100 photos by John K. Nakata, Charles E. Meyer, and others portray some of the
damage resulting from the earthquake.
USGS Professional Papers on Loma Prieta
Four Loma Prieta Earthquake Professional Papers, each containing multiple
chapters, document the magnitude 6.9 earthquake that shook the San
Francisco and Monterey Bay regions.
- Professional Paper 1550: Earthquake Occurrence
- Professional Paper 1551: Strong Ground Motion and Ground Failure
- Professional Paper 1552: Performance of the Built Environment
- Professional Paper 1553: Societal Response