. The recurrence intervals (times between earthquakes) at Wrightwood are more regular than clustered (determined by a mathematical analysis), and only four times in the past has the interval between two major earthquakes been longer than the current interval (since 1857). San Andreas. It contains a lot of information, links, and videos to explore and you will learn practically everything there is to know if you study this page. Bold numbers show the average time between big earthquakes, determined at paleoseismic sites (triangles). Scientists say the region appears to be overdue for a significant quake. The Hayward fault in the San Francisco Bay area runs through a densely-populated area, so it has been studied quite a bit.The most recent major earthquake on this fault was approximately M6.9 and occurred in 1868. The four areas singled out in the study are: Hayward, Rodgers Creek, northern Calaveras and Green Valley. The similar magnitude 2011 Tohoku 9.0 earthquake that caused the Fukushima nuclear disaster is discussed in this 3-minute video. It is now thought to be the âticking time bombâ fault line and more dangerous than the San Andres. The Hayward fault dataset includes 1489 earthquakes with magnitudes from â¦ The slip rate near the San Andreas fault is â¦ Along the San Francisco peninsula no detectable slip occurs (less than 1.5 mm/yr) at the surface, but appreciable strain is accumulating. In particular, we need to design buildings and infrastructure to be able to withstand the earthquake shaking or be easily repaired. The San Andreas has long been the quake fault California fears the most. A section of sidewalk in Hayward that showed the movement of the Hayward Fault was 'fixed' by the city, much to the dismay of geologists. DAMAGE LIKE THIS IS A VERY REAL POSSIBILITY WHEN THE CASCADIA SUBDUCTION ZONE RUPTURES, Retrofitting Bay Area Homes for 25 Years and Still Counting, The Coming Bay Area Earthquake: 2010 Update of Scenario for a Magnitude 7.0 Earthquake on the Hayward Fault. At that location, the record is about 1000 years long, and in that time period, there are about 9 large earthquakes recorded in the sediments, including the 1857 rupture. The last major earthquake that the Hayward fault produced was in 1868. Using the forecasts, we can properly engineer structures, plan for earthquake response, and be prepared at home to make a big difference in the impact of a significant earthquake. ...and thank-you to the Facebook poster who gave us the idea for the title! The San Andreas Fault is the most famous fault in the world. North to south, it runs from just west of Pinole Point on the south shore of San Pablo Bay and through Berkeley (just under the western rim of the While the San Andreas fault that triggered the great 1906 San Francisco earthquake has become ingrained in California culture, new â¦ The paleoseismic data on different parts of the San Andreas Fault Zone are all telling us that some sections appear to be past the average, or "overdue" for a significant earthquake. Analysis of a geodetic network of 115 lines crossing the San Andreas, Hayward, and Calaveras faults in the vicinity of San Francisco Bay and measured repeatedly between 1970 and 1980 has revealed details about the accommodation of relative plate motion in this area. The Hayward Fault is an offset of the San Andreas Fault system that dominates the landforms of eastern San Francisco Bay. But focusing only on avoiding an earthquake doesn’t address most of the effects from the shaking. No one can predict earthquakes, so what does the science really say? San Francisco Bay and Parkï¬eld that have preinstrumental and modern earthquake epicenters and have towns that can provide felt intensities. The USGS also has a webpage that analyzes what will happen if a 7.0 earthquake has its epicenter in Oakland or Fremont. The Hayward Fault Zone is a geologic fault zone capable of generating destructive earthquakes. The fault divides into three segments, each with different characteristics and a different degree of earthquake risk. This includes Cripple Wall Retrofits, No Cripple Wall Retrofits, Retrofits of Homes with Living Area above a Garage, and Hillside Home Retrofits, THE SAN ANDREAS FAULT IS QUITE DANGEROUS AND CAN CREATE AN EARTHQUAKE 8.0 OR MORE ON THE RICHTER SCALE. However, creep occurs in spots along the Hayward Fault. The corrosion problem of ACQ treated lumber. The Hayward fault runs through the East Bay hills from Richmond to San Jose. The Hayward fault slips in large earthquakes and by aseismic creep observed along its surface trace. The Hazel Dell site near Corralitos, CA was trenched in 2013 to characterize the Santa Cruz Mountains section of the San Andreas Fault. Fault-plane reflections reveal that two of these faults, the San Andreas and Hayward, dip toward each other below seismogenic depths at 60?? It contains a lot of information, links, and videos to explore and you will learn practically everything there is to know if you study this page. As you returned to your home, you would probably see damaged and collapsed buildings and bridges, broken pipes and snapped power lines and scorched remains of fires. Although the region was sparsely populated, the quake on the Hayward Fault was one of the most destructive in Californiaâs history. ?, respectively, and persist to the base of the crust. A paleoseismic study in 2007 at Tyson’s Lagoon (now a BART station) found evidence for 12 paleoearthquakes (including the historical 1868 earthquake) with an average time between earthquakes of about 160 years. Public domain.). This in turn can cause the Hayward Fault to rupture. The San Andreas fault zone has been a very significant source of major California earthquakes. The Hayward fault in the San Francisco Bay area runs through a densely-populated area, so it has been studied quite a bit.The most recent major earthquake on this fault was approximately M6.9 and occurred in 1868. This shows that the average time between earthquakes includes some intervals that are short and some intervals that are long. Introduction  The Hayward Fault is located on the eastern side of San Francisco Bay, California, and forms one branch of the San Andreas Fault system that accommodates the relative motion between the North American and Pacific plates. It forms the tectonic boundary between the Pacific Plate and the North American Plate, and its motion is right-lateral strike-slip (horizontal). Running for nearly 74 miles through cities including Fremont, Hayward, Oakland, Berkeley, and Richmond, the Hayward Fault has the potential to wreak more havoc than most California faults. 408-664-6355
Earthquake country just got a little scarier. The San Andreas fault caused the biggest earthquakes in California with an approximate magnitude 7.9 in 1857 (Southern California) and 1906 (San Francisco). The author Kathryn Schultz writes “When the next very big earthquake hits, the northwest edge of the continent, from California to Canada and the continental shelf to the Cascades, will drop by as much as six feet and rebound thirty to a hundred feet to the west . We test this method on both the Hayward Fault and San Andreas Fault at Parkfield, California. The plate is moving slowly all the time, but the edges move in fits and starts. Basically, because itâs a big fault that is close to some big cities. 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 â¼7 millimeters per year to the bottom of the seismogenic zone along a â¼20-kilometer-long northern fault segment. The highway paralleling the lakes to the left is Interstate 280, ``the most beautiful urban highway in the United States''. The fault has been creeping about 4.6 mm/yr (0.2 inches/yr) for the last several decades, but that is only half of the long-term slip rate, so stress is building upon this fault. The entire San Andreas fault system is more than 800 miles long and extends to depths of at least 10 miles within the Earth. The Calaveras Fault is a major branch of the San Andreas Fault System that is located in northern California in the San Francisco Bay Area.Activity on the different segments of the fault includes moderate and large earthquakes as well as aseismic creep.The last large event was the 1984 Morgan Hill event and the last moderate earthquake was the 2007 Alum Rock event. The North Coast section of the San Andreas Fault is north of San Francisco. CHART SHOWING THE MAGNITUDE AND DATES OF LARGE EARTHQUAKES IN CALIFORNIA. The resulting 3000-year record includes 29 surface-rupturing earthquakes. The average time interval between the 5 most recent earthquakes is a little shorter, about 140 years. Posted April 19, 2018, under Blog. No data point selected. The San Andreas Fault is a continental transform fault that extends roughly 1,200 kilometers (750 mi) through California. Historic information doesn’t provide enough data to establish whether or not there is a pattern in the timing of earthquakes, but paleoseismology has provided an abundance of data. First, let's zoom out and look at the big picture. CHART SHOWING THE HISTORY OF LARGE EARTHQUAKES ALONG THE CASCADIA EARTHQUAKE TIME LINE, MIRROR IMAGE COMPARISON BETWEEN THE CASCADIA FAULT SHOWN ON THE RIGHT AND THE SUMATRA EARTHQUAKE ON THE LEFT THAT KILLED OVER 260,000 PEOPLE. In fact, it was considered the âgreat earthquakeâ until the San Andreas Fault tore San Francisco apart 38 years later. Thick red lines show the extent of historic ruptures. And what does it mean? The Hayward fault under Oakland is more dangerous than the well-known San Andreas fault in Southern California, according to a new study that says it has the potential to kill at least 800 people and injure 18,000 more, The Los Angeles Times reported. The Hayward fault is a 90 kilometer long crack in the Earth's crust that travels through the San Francisco Bay area. Here is the graphic history of earthquakes on the Hayward fault. Where does the information come from? However, creep occurs in spots along the Hayward Fault. It runs through densely populated areas, including Richmond, El Cerrito, Berkeley, Oakland, San Leandro, Castro Valley, Hayward, Union City, Fremont, and San Jose. The Hayward Fault runs south through densely populated areas, including the cities of Richmond, El Cerrito, Berkeley, Oakland, San Leandro, Hayward, Union city, Fremont, and San Jose. Earthquake country just got a little scarier. Investigating Past Earthquakes to Inform the Future. CBS News did a short but excellent documentary on the huge impact a rupture of the Cascadia Fault will have on our country. The Hayward Fault is a "tectonic time bomb, due any time for another magnitude 6.8 to 7.0 earthquake," according to a 2008 USGS report. The San Andreas Fault and the San Francisco Bay Area This image shows San Andreas Lake and Crystal Springs reservoir from the air, looking SouthEast from HERE. The San Andreas Fault is a continental transform fault that extends roughly 1,200 kilometers (750 mi) through California. But the data can’t be used to make predictions: we do not understand earthquakes well enough to know exactly where the next earthquake will occur, what the magnitude will be, or exactly when it will happen. On October 21, 1868, a magnitude 6.8 earthquake struck the San Francisco Bay area. Its last major rupture occurred in 1868, during California's frontier days, and was the original "Great San Francisco Earthquake" until 1906.. Map of faults in southern California. Many of the sites paleoseismologists have been studying are along key sections of the SAFZ where there is a large population or major infrastructure that would be affected by a large earthquake in the future. This website is intended to help clients of Bay Area Retrofit to understand their retrofit proposals. Each house is unique. (Public domain.). This page was last edited on 23 August 2020, at 21:45. unconsolidated surficial deposits. Geographic Names Information System (GNIS), Mapping, Remote Sensing, and Geospatial Data, Earthquake Outlook for the San Francisco Bay Region 2014—2043, Map of active faults and historic ruptures in California, New Information About the San Andreas Fault, Catching Glimpses of Centuries-Old Earthquakes, Science of the New Madrid Seismic Zone - Paleoseismology, UCERF3: A New Earthquake Forecast for California’s Complex Fault System. The New Yorker published an article, “The Really Big One,” which warns that the Cascadia Fault is even more dangerous than the Hayward Fault. The Hayward Fault. The highway paralleling the lakes to the left is Interstate 280, ``the most beautiful urban highway in the United States''. According to a new study, the Hayward fault line that runs under Oakland, California is believed to be more dangerous than the infamous San Andreas fault line that spans Southern California.. The threat to San Francisco from the Hayward fault was recognized by A. C. Lawson in 1908 in Report of the State Earthquake Commission, The California earthquake of April 18, 1906, p. 447: "The foot of Market Street, San Francisco, is about midway between the San Andreas rift and the fault scarp upon which movement occurred in 1868. Since then, nearly three million people have moved next to the Hayward fault with little regard for its earthquake potential. What does the science say? Four urban areas of the San Andreas Fault System in Northern California have accumulated a sufficient amount of energy to produce major earthquakes, a new study finds. Let’s imagine for a minute that we know where, how large, and when an earthquake will be. The scariest scenario for the next major earthquake may [â¦] New studies farther to the northwest along the Peninsula section of the San Andreas Fault also show a long interval between the 1906 earthquake and the previous earthquake, which occurred around 1300. Since then, nearly three million people have moved next to the Hayward fault with little regard for its earthquake potential. It has an average repeat cycle of 140 years. West of the San Andreas fault, the 400-kilometer-long San Gregorio-Hosgri fault extends primarily offshore between Point Conception and Bolinas, and sits within 3 nautical miles (in state waters) of the Diablo Canyon Power Plant. Let's start in southern California and work our way north. Homeowner’s Guide to Seismic Retrofitting. Scientists say the region appears to be overdue for a significant quake. Scientists have a good big picture understanding of the San Andreas Fault Zone (SAFZ). The Hayward Fault Zone is located in northern California in the San Francisco Bay Area. The San Andreas has long been the quake fault California fears the most. 1 B). History shows that five large earthquakes on the Hayward fault have occurred on average every 150 yearsâlast being in 1868. The Hayward Fault splinters from the Calaveras Fault, which itself is an offshoot of the As of 2020 it has been 151 years since the last big earthquake in 1868. It is similar to riding in the back of a pick-up truck which accelerates very quickly and stops suddenly. The Hayward fault is due for another large earthquake very soon. Public domain.). 510-548-1111. Workers' Comp RWCC64393236
San Andreas. In northern California, the zone includes the Hayward, Calaveras, as well as the Northern San Andreas and other faults, and in southern California, the zone is even wider, encompassing the Southern San Andreas, the San Jacinto, and other faults in the Los Angeles area. The Hayward Fault dissects Fremont creating offset features. A pair of major earthquakes occurred on the central to southern region, where the 1857 faulting overlapped the 1812 earthquake faulting. Other articles where Hayward Fault is discussed: California: Relief: The Hayward Fault in the San Francisco Bay Area and the San Gabriel fault zone in metropolitan Los Angeles have produced several major earthquakes, though the destructive quake centred in the Los Angeles suburb of Northridge in 1994 occurred along one of the San Andreasâs largerâ¦ Maybe you’ve heard that the “Big One is overdue” on the San Andreas Fault. You might think that would be good because then you could leave the area beforehand and then return after the earthquake. San Jose earthquake risk is caused by three connected faults: Hayward, Calaveras, and San Andreas. THE HAYWARD FAULT IS CONNECTED TO A SERIES OF SMALLER FAULT THAT MIGHT ERUPT AT THE SAME TIME CREATING A 7.3 OR HIGHER MAGNITUDE EARTHQUAKE. With about 45 years between the historic earthquakes but about 160 years since the last one, it is clear that the fault does not behave like a clock with a regular beat. The most striking result is that the deformation is not uniformly distributed across the area. The Hayward Fault. Or is the size of the 1812 earthquake (~M7.1) more common? Many earthquakes have occurred along it, including famous ones in 1857, 1906 and 1989. This means that earthquakes as large as M=7.4 are possible on both sides of San Francisco Bay, rather than just on the San Andreas, as we had thought before. The Hayward Fault is a "tectonic time bomb, due any time for another magnitude 6.8 to 7.0 earthquake," according to a 2008 USGS report. The horizontal colored lines highlight different layers of sediment. The Hayward Fault is 40 miles long and about 8 miles deep and trends along the east side of San Francisco Bay. Scientists are keeping a nervous eye on the Hayward fault, which runs along the most urbanized edge of San Franciscoâs East Bay.The Hayward fault activity is capable of generating destructive earthquakes. The San Andreas Fault and 6 other significant fault zones are present in the Bay Area: the Calaveras, Concord-Green Valley, Greenville, Hayward, Rodgers Creek, and San Gregorio Faults. Comparing the data from sites like Wrightwood and Frazier Mountain, earthquake scientists are working to understand the pattern of large earthquakes – asking questions such as how typical was the large (M7.9) earthquake in 1857? The faults shown here are represented by simple lines which do not convey how complicated they can be. HAYWARD FAULT RUNNING THROUGH CENTER OF UC BERKELEY SPORTS STADIUM.. MOVEMENT OF EARTH SHOWING HOW EARTHQUAKES DAMAGE HOUSES. 1 A). . This fault is about 74 mi (119 km) long, situated mainly along the western base of the hills on the east side of San Francisco Bay.