This satellite view shows the approximate trace of the San Andreas Fault across California.
A fault trace is a line on a map where the fault is believed to intersect Earth's surface.
Use the buttons in the upper left corner of the map window to zoom in and out and follow
the fault across California. You can switch between map, satellite, and hybrid views by
clicking the buttons in the upper right corner of the map window. Details about this map, how it
was made and how accurate it might be are given below.
The San Andreas Fault trace shown on this map is approximate. It was created by measuring
the latitude and longitude for many points along the fault trace from maps published
by the United States Geological Survey, California Geological Survey and other sources (a
detailed list of these publications can be seen here). These points are shown on
the map as small red squares. The light red lines that connect the squares are linear
interpolations. This yields a map that shows the approximate location of the fault. The
points and the lines shown on this map are generally within about one hundred feet (actual
ground distance) of where the authors of the source documents plotted them - however there are locations where greater divergence occur.
This map provides a visual presentation of the fault in a format that can be easily
transmitted via the web to a very large number of people who might otherwise know very little about
the fault's location. We have chosen to represent the fault as a thin line, not because the location is
known that precisely, but because we do not want to obscure ground features and evidence of the fault's
location that can be seen in the satellite images.
The concept of this map was created by Dr. David K. Lynch, author of
Field Guide to the San Andreas Fault and Dr. Hobart M. King,
publisher of Geology.com. The Google map was created by Bradley
Cole, cartographer, Geology.com. We thank
Google and authors of the publications used to obtain the latitude and longitude estimates that serve as the basis for this map.