Physics
Scientific paper
Jun 1997
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997georl..24.1307b&link_type=abstract
Geophysical Research Letters, Volume 24, Issue 11, p. 1307-1310
Physics
8
Tectonophysics: Plate Boundary-General, Tectonophysics: Instruments And Techniques
Scientific paper
Surface creep on the Hayward fault at Fremont has been sustained for the past century at 8.2+/-0.1mm/year. Two surface creepmeters record a similar mean creep rate in the past 3 years, but the data show significant irregularity despite being anchored at depths of 10-28 m. The serendipitous piercing of the subsurface fault by one of the creepmeter anchors, whose deflection at depth has been regularly monitored with a biaxial inclinometer system, reveals two fault traces dipping at ~70°. At 21 m depth the Hayward fault slips dextrally at 8.1+/-0.4mm/yr, and at ~7m depth a subsidiary fault slips bidirectionally adding noise to the surface creep data. Surface creep on this segment of the Hayward fault was arrested by stress changes following the 1989 Loma Prieta earthquake, but resumed in 1994. Tilt of the borehole, and a similar borehole east of the fault, is 3 orders of magnitude too large to be driven by uniform creep extending to depths of several km, and we conclude that irregular slip on the fault occurs in the uppermost few hundred meters. Cumulative dilatational strain since 1868 near segments of the fault NW of the creepmeter may exceed 200 μstrain, unless absorbed by undocumented slip off the main fault trace.
Bilham Roger
Whitehead Scott
No associations
LandOfFree
Subsurface creep on the Hayward fault, Fremont, California does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Subsurface creep on the Hayward fault, Fremont, California, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Subsurface creep on the Hayward fault, Fremont, California will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1473813