Link to USGS home page
USGS Home
Contact USGS
Search USGS
Coastal & Marine Geology InfoBank

USGS CMG InfoBank: Surprising Behavior of the San Andreas Fault

Skip navigational links
Search InfoBank
Home tab FACS tab Activities tab Atlas tab Geology School tab More tab More tab Geology School tabs
   
Dictionaries: The USGS and Science Education   USGS Fact Sheets   Topics   Keywords   Data Dictionary   Metadata Dictionary   Computer Terminology   Digital Formats
InfoBank Terms: Activity ID   activity overview   crew   formal metadata   lines   metadata   NGDC   port stops   project/theme   region   ship   stations   time   virtual globe   year  
Data Types: bathymetry   geodetic positioning   gravity   ground penetrating radar   imagery   LIDAR   magnetics   metering equipment   navigation   samples   seismic   definitions disclaimer  
Data Formats: ARC coverage   E00   FGDC metadata   gridded/image   imaging   material   scattered/swath   Shapefile   vector/polygon  
   
Comment: 11:29 - 12:49 (01:20)

Source: Annenberg/CPB Resources - Earth Revealed - 25. Living With Earth, Part I

Keywords: "William Bakun", geologist, earthquake, "Loma Prieta Earthquake", fault, "San Andreas Fault", "strike-slip fault", focus, fissure, landslide

Our transcription: As research efforts continue, geologists begin to recognize that there are a number of surprising aspects to this quake.

One of the interesting things about the Loma Prieta Earthquake was that the fault that broke was not the vertical strike-slip fault that we tend to think of as characterizing the San Andreas Fault.

Geologists normally expect the two sides of the San Andreas Fault to slip past each other horizontally with the west side moving to the northwest.

This did, in fact happen, but the west side also moved vertically riding up on the eastside between one and two meters.

What also catches the attention of geologists is that the focus of the quake occurred 18 kilometers beneath the surface surprisingly deep for California earthquakes.

Perhaps because the quake was so deep-seated, no rupture broke the surface along the fault, but numerous fissures resulted form landslides triggered by the shaking.

Geology School Keywords

Skip footer navigational links


InfoBank   Menlo Park & Santa Cruz Centers   St. Petersburg Center   Woods Hole Center   Coastal and Marine Geology Program   Geologic Information   Ask-A-Geologist   USGS Disclaimer  

FirstGov button   Take Pride in America button