The Hayward fault (HF) in California exhibits large (M w 6.5–7.1) earthquakes with short recurrence times (161±65 yr), probably kept short by a 26%–78% aseismic release rate (including postseismic).Its interseismic release rate varies locally over time, as we infer from many decades of surface creep data. On April 15, 2006, Drs. When people learn about it, they often wonder if fault creep can defuse future earthquakes, or make them smaller. In San Pablo Bay, there is a distinct along-strike surface creep rate gradient between 5.4 mm/year along the northern Hayward fault and 1.5 mm/year along the southern Rodgers Creek fault . What they found was that the Hayward Fault has enough stored energy to produce a 6.8-magnitude quake, while the Rodgers Creek and Green Valley faults each have stored enough to trigger a … Since then, nearly three million people have moved next to the Hayward fault with little regard for its earthquake potential. To those who still can’t get enough of this amazing geologic feature, this post’s for you. In my very second post, back in 2007, I suggested that we take over the name, and a couple years back I pointed out eight iconic places to see the Oakland fault in action. The answer is … The steady creep along the fault results in relative displacement of the two parts of the stadium. There are many easy tours you can take to get a closer look at this subterranean beast, as well as maps to find out how close you live to the fault and what seismic hazards—such as landslides or liquefaction—exist near you. Creep rates over … Second, and more importantly, knowing where and how fast the Hayward fault creeps allows us to make estimates of where it is not creeping. In the Figure you can see the almost 90 degrees change in the course of the stream. Creep is steady fault movement, varying from continuous to episodic with creep events lasting minutes to days. Aseismic creep occurs in the uppermost 5 km of the Hayward fault, faster in the south (6-9 mm/yr) than in the north (5 mm/yr). Streets crossing the fault in Hollister show significant offset and several houses sitting atop the fault are notably twisted (yet habitable). The Hayward fault is a 90 kilometer long crack in the Earth's crust that travels through the San Francisco Bay area. The Hayward fault is considered to be one of the primary hazards in the San Francisco Bay region. Professor Douglas Dreger, of the Berkeley Seismological Laboratory, University of California at Berkeley. There, most of the fault between the surface and its base at around 15 kilometers depth turns out weak and slippery, and only a narrow band of rock in the middle of that range has enough friction to gather a lot of strain energy. Among other things, I talked about the fault's peculiar behavior called aseismic creep, in which the two sides of the fault move slowly past each other at just a few millimeters per year without the help of … They clearly show the right lateral movement of the fault as depicted on the road. (In this picture the Bay Area is near the edge of that pattern, so while our faults creep they still are considered able to clobber us with magnitude-7 events.). The Hayward fault slips in large earthquakes and by aseismic creep observed along its surface trace. Its last major rupture occurred in 1868, during California's frontier days, and was the original "Great San Francisco Earthquake" until 1906.. See them shown in blue in this figure from the Geology paper. Its paleoearthquake record suggests such events occur regularly and frequently, with a 161 65 1σ and 10 yr (1standard error of the mean) mean recurrence interval (Lienkaemper et al., 2010). On its west side, the drip is still attached and pulling down on the crust. In spite of this, the fault has also experienced moderate to large earthquakes. Figure 3 also shows nicely how the sidewalk and pavement are damaged only in the zone of the Hayward trace. Dislocation models of the surface deformation adjacent to the Hayward fault measured with the global positioning system and interferometric synthetic aperture radar favor creep at ∼7 millimeters per year to the bottom of the seismogenic zone along a ∼20-kilometer-long northern fault … The Hayward fault is an extremely interesting feature of the East Bay and you can see its footprints all over the place once you know where and how to look. The Hayward fault has a creep mechanism, where the surface shows signs of a steady movement while the tectonic plates are locked together deep below the surface of the earth. 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