Significant Earthquakes and Faults
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
Fault Name Index
Clamshell - Sawpit Canyon Fault
Type of Fault: reverse
Length: 18 km
Nearby Communities: Sierra Madre, Monrovia
Most Recent Surface Rupture: Late Quaternary
Other Notes: This fault dips to the north at about 40 (at the surface) to 50 (at depth) degrees.
The Sierra Madre earthquake of 1991 probably originated on the Clamshell - Sawpit Canyon fault. Though a sizable earthquake, the depth of this quake prevented the rupture from reaching the surface.
This fault is featured on the following maps:
Mojave Fault Map
Southern Fault Map
Los Angeles Fault Map