Latitude: N 33°50'10"
Longitude: W 116°18'25"W
Length: 1419.45m
Number of Bench marks: 41
Number of Surveys to 2000: 5
Date of Initial Survey: 22 August 1992
Date of Latest Survey: 24 September 1996
Trespass Permission: The land is owned by The Nature Conservancy,
and notice to survey the line must be given in advance. It is extremely important
not to drive vehicles onto any part of The Nature Conservancy land, including
dirt roads that lead off onto Conservancy land. Failure to do so will result
in the citation by local law enforcement as well as a permanent ban on surveying
this line.
Directions: Take I-10 in Coachella Valley to Ramon Road. Proceed
east on Ramon Road 4.6 miles to Thousand Palms Canyon Road. Turn left and
proceed 1.8 miles to turnout on right side of the road. A trail head sign
is 15 m from the east edge of the turn out. The trail head sign is between
bench marks TPC23 and TPC24. The line trends N45oE in the wash. Take your
valuables with you.
Comments: This line crosses the Mission Creek fault approximately
between bench marks TPC20 and TPC21. The line was established to measure
vertical displacement on the fault along the north edge of the Indio Hills.
Results:
Between August 1992 and December 1992, the line apparently tilted south
southwestward about 3 microradians without displacement at the Mission Creek
fault. Since 1992, the northeast side of the line is flattening to with
1 mm of its initial position, defining, thereby, a small arch on the northeast
side of the fault zone.
Reference:
Clark, M. M., 1984. Map showing recently active breaks along the San Andreas
fault and associated faults between Salton Sea and Whitewater River - Mission
Creek, California. U.S. Geological Survey Map I-1483, 1:24,000.
Sylvester, A. G., 1993. Investigation of nearfield postseismic slip following
the M W 7.3 Landers earthquake sequence of 28 June 1992, California. Geophysical
Research Letters 20, 1079-1082.
Up one level
Return to the Title Page.