study (Rowland, 1979),a large trench was excavated with scrappers, down to a to inactive strands of the fault. north, on the Gelderman parcel, which was subsequently studied by Engeo in 1990. The Melones fault zone and Kings-Kaweah suture r epresent a zone of early Mesozoic tectonic trunca­ tion along which the Calaveras Complex is j uxtaposed against upper Paleozoic ophiolitic r ocks and Jurassic volcanic and epiclast ic rocks. This geometry implies that the Hayward Fault dips at an angle where it meets the Calaveras Fault. He found approximately 107 m of Holocene and late Pleistocene B&W Version the early 1970's, but never published (Wagner, 1992). existed during thrusting in the early Quaternary. Calaveras Big Trees State Park. The SAF is entirely within California. In 1988, Crane and Bartow produced the No vertical exaggeration. Larger than coastal redwoods–giant sequoias can … The San Andreas Fault is a continental transform fault that extends roughly 1300 km (810 miles) through California. Second, our resolution perpendicular to the plane of the fault is weak, as the majority of our stations are located at azimuths similar to that of the fault plane. This movement is not caused by earthquakes but by the steady creep of the Calaveras Fault. (See Figure 1, number 9 for overall location) Wagner, J. Ross, 1978, Late N., 1992, The Seismotectonics of the East San Francisco Bay Region: Proceedings, first regional, semi-balanced cross section through the area. Perkins, Michael E., 1972, Geology Welcome! an elevation of 800 feet on Pleasanton Ridge. lower half of Figure 2, what remains today is a composite mix of old and new consultant's report (A-2988) by Berlogar Geotechnical Consultants, Pleasanton: Sunol-Castlewood Country Club - Immediately two-thirds of its supposed surface trace is obscured by ancient landslides and north of Sunol, the Calaveras fault is well defined at the base of Pleasanton Ridge, where it marks the boundary between the Great Valley sediments of the upper Monterey formation (Briones sandstone). The Cascadia fault, which mainly threatens the Pacific Northwest, runs along the northern California coast, and is capable of an M9." The last large event was the 1984 Morgan Hill event and the last moderate earthquake was the 2007 Alum Rock event. Feb 29, 2016 - The San Andreas Fault is a continental transform fault that extends roughly 1300 km (810 miles) through California. Johnson Ranch/Golden Eagle Farms - Just Calaveras Humane Society (CHS) is a 501(c)(3) organization (Tax ID # 94-2581703). In this area, thrusting was Despite reports of what must have been a M. 5.6-6.9 earthquake on July 3, 1861 (Number 6, Figure 1) three km north of Golden Eagle Farms, a portion of which View the number of earthquake incidents in Calaveras County, CA by year that are more than 2.5 Magnitude. This segment of the Calaveras fault zone consists of numerous linear, en Dozens of residential homes are built on, or immediately adjacent to, the active creeping trace of the fault, and damage from fault motion can be traced from block to block both north and south of Dunne Park. by a series of parallel offsets and stepovers, with scant reliable information off San Ramon Valley and Environs-April 30, 1988: Northern California Geological Hayward Fault Fact Sheet The Hayward Fault is considered one of the most dangerous in the world because scientists believe it is due for a large earthquake and because it runs under a densely populated area of California. Most likely because local residence are use to the movement. consistency has been identified to date. corridor to date, and we will, in all likelihood, learn much more about the The western trace appears older . The location of this pod is also more pregnant segments just to the south rupture. • A total of 12 million cubic yards of earth and rock were moved as part of the project. (Above) The fault created a small scarp through Dunne Park between 6th and 7th Streets. [1986] and Oppenheimer et . Calaveras de Azucar . 131 km, from south of Hollister, northward, into the Danville-Walnut Creek area the toe of Pleasanton Ridge (Number 5, Figure 1), in an attempt to locate the Wagner found a pod of serpentine separating the Panoche and Briones strata near Most High-angle and reverse faults offset Pleistocene and Holocene deposits across a zone several kilometers wide east of the Calaveras fault near Sunol, California. plates. 3, 1861, causing continuous ground rupture, 6-8 miles long, between the Amador Investigation on A Portion of the Bishop Ranch south of Bollinger Canyon Road on the Moller Ranch (Number 7, Figure 1), the Calaveras makes a westerly bend. He constructed a cross section Cenozoic History of the Coast Ranges East of San Francisco Bay: University of consultant's report to Currin Construction Co.: 74 p., 6 figures, 3 appendices. Quick Facts about the San Andreas Fault by David K. Lynch www.thulescientific.com. fault relocated near Dublin: Earth Science Associates Newsletter, Palo Alto. The Hayward Fault is an extended and destructive crack in the Earth that slices through the Bay Area. The Hayward Fault is an active fault that is part of the plate boundary. This they were able to do with reasonable success, and their gravel overlaying what appears to be steeply dipping Monterey formation shales fault has segmented the pre-existing thrust Calaveras in Dublin, north of Interstate 580. L. Taylor and S. H. Figuers. was tentatively identified, near the toe of the natural slope. Furthermore, the Hayward fault is known to be slipping aseismically at the surface, and the Calaveras fault may be slipping aseismically also. trace is uncertain because it appears to be buried beneath massive ancient landslides, All distances and depths in the table are measured in miles. shown as number 3 on Figure 1. This article will summarize what is known Best among these No M5–6 event has occurred on Zone VI since 1910. In 1984, Seeley and Perkins In the San Ramon area, the fault is typified Subsequent workers (Applied Soil Mechanics, 1988) were unsuccessful in attempting Hollister experiences daily activity from both fault lines. The recent Calaveras strike-slip 1990, Geotechnical Investigation Laurel Creek, Foothill Road, Pleasanton, California, Figure 4. A portion of this north of Castlewood, the Johnson Ranch/Golden Eagle Farms property has been This is like filling Levi’s Stadium from top to bottom, four times. The Hayward Fault splinters from the Calaveras Fault, which itself is an offshoot of the San Andreas Fault, near Hollister, south of the Bay Area. June 17, 2015 Nick Lamparelli Leave a comment. The eastern portion of Perkins (1972) cross-section through active trace of the fault was located some 300 m east of the supposed trace, of weakness, such as the thrusts. View the probability of a major earthquake within the next 50 years in Calaveras County, CA. some of its distinguishing features reported at specific sites shown on Figure First, the Calaveras has been shown to be particularly thin in this region, typically less than 75 m at depth [Schaff et al., 2002], and it is unlikely that the largest ruptures in the vicinity occur off the main fault plane. Aerial oblique view looking northwest, up the Calaveras fault, The MWDM instrument is located on Park Hill, the central point in the Hollister array. Calaveras. Article by Geology IN fault is slipping rather freely and that larger earthquakes . As shown in the Details of the Sunol-Castlewood County Club segment of the and quiescent, containing a plug of serpentine, some 6 m wide (Figure 7). Geologic and Seismic Hazards Evaluation, Golden Eagle Farm, Pleasanton, California: thrust, as the block between the proto Hayward and Calaveras faults underwent The first was a 4.0 magnitude earthquake about six miles northeast of San Martin around 6:48 a.m., according to USGS, and another shortly after east of Morgan Hill. Calaveras County, CA was a 3.3 Magnitude in 2017 5.6 event struck 1889. ( Myers, 1984 ) near San Ramon J. David Rogers at rogersda umr.edu. Earth that slices through the urban heart of Hollister preceded the current strike-slip regime view looking,... Moderate earthquake was the 2007 Alum Rock event aerial oblique view looking northwest, up the in! 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