san fernando valley earthquake 1971

Earthquakes are best described as a shaking or vibration of the ground caused by breaking of rock. San Fernando Valley earthquake of Feb. 1971, Sylmar, California Public Domain 1971 May 14;172(3984):712-5. "Earthquake" captures all the drama, suspense, pathos, and even humor, of the San Fernando Valley Quake of 1971. It also occurred on a hitherto unknown fault, albeit a different one from the San Fernando fault (see Figure 2). from California Geology, April/May 1971, Vol. The Slides in the San Fernando Dams During the Earthquake of February 9, 1971. The 1971 San Fernando earthquake (magnitude 6.7) collapsed four buildings at the San Fernando Veterans Administration Hospital complex (above), killing 47 people Damage from the San Fernando Earthquake, in the San Fernando Valley, Southern California. All rights reserved. The Symlar San Fernando Valley Earthquake of 1971. Yerkes -- Main shock and larger aftershocks of the San Fernando earthquake, February 9 through March 1, 1971 / C.R. Introduction / Arthur Grantz -- An estimate of the damage / Reuben Kachadoorian -- Geologic setting and activity of faults in the San Fernando area, California / Carl M. Wentworth and R.F. The red line is the fault on which the Northridge quake occurred in 1994. San fernando earthquake of 9 february 1971: pattern of faulting. Blind Thrust "Earthquake" captures all the drama, suspense, pathos, and even humor, of the San Fernando Valley Quake of 1971. Even more surprising was the location of the focus of the quake, which later came to be known as the San Fernando earthquake. There are various names for this earthquake. Download a PDF of "San Fernando Earthquake of February 9, 1971" by the National Research Council for free. 45 years ago - 1971 Sylmar earthquake... Did you experience it? The worst damage was done here being newly opened (one This event included 4 aftershock quakes with magnitudes around 5. Earthquakes are best described as a shaking or vibration of the ground caused by breaking of rock. Also known as the Sylmar Earthquake, the magnitude-6.5 quake was reported on a Tuesday at about 6:01 a.m. Its origin was in the foothills of the San Gabriel Mountains north of Los Angeles, but shaking was felt across a widespread part of the San Fernando Valley. Today in Earthquake History: San Fernando 1971. It bans construction on active faults in California. found: Wikipedia, Feb. 24, 2006 (The Sylmar earthquake struck at 6:00:55 a.m. PST on the morning of February 9, 1971. | Final report}, author = {Schiff, A J and Yao, J T.P. When seismologists checked their records they were utterly surprised. Retro and Weird. The San Fernando earthquake of February 9, 1971, was a geologic phenomenon not unlike many similar earthquakes that occur every year around the world. During the Northridge earthquake in January 1994, more than 50 people were killed and the quake caused damage worth $35 billion. The two geologists Carl Wentworth and Robert Yerkes from the US Geological Survey in Pasadena later wrote that "the San Fernando fault was discovered to be active only when it ruptured the ground surface on February 9, 1971. | Some decades later, the San Fernando earthquake affected the San Fernando Valley north of Los Angeles with heavy damage to several hospitals. Although the Richter magnitude of the tremblor was 6.6, ranking it as moderate to large, but not great, it shook a wide, â¦ Material from 1971 San Fernando earthquake was split to Sierra Madre Fault Zone on 23:28, 19 March 2017 from this version.The former page's history now serves to provide attribution for that content in the latter page, and it must not be deleted so long as the latter page exists. The epicenter of the quake was located in the San Gabriel Mountains, with numerous nearby Los Angeles communities affected. There are various names for this earthquake. Sylmar Earthquake 1971 Hospital Damage. San Fernando Juvenile Hall, after earthquake, 1971 Creator Unknown Date Created and/or Issued 1971-02 2001-08-27 Publication Information California State University, Northridge. The San Fernando earthquake has been extensively studied by many seismologists, geologists, and earthquake â¦ The earthquake that rocked the northern San Fernando Valley, near Sylmar measured magnitude 6.6 on the Richter magnitude scale. : San Fernando Juvenile Hall, after earthquake, 1971 : Foothill Freeway after earthquake, 1971 : Olive View Medical Center after the 1971 Sylmar quake, before demolition The 1971 San Fernando earthquake, also known as Sylmar earthquake, struck the San Fernando Valley near Sylmar at 6:00:55 a.m. PST on Feb. 9, 1971â¦ | This event included 4 aftershock quakes with magnitudes around 5. 21st century Contemporary era. We evacuated because the Van Norman Dam was cracked, and they thought it might burst down on the valley! Figure 2: Earthquakes on two blind thrust faults caused severe damage in the San Fernando Valley. The February 9, 1971 earthquake in San Fernando Valley, California, caused slides in the embankments of two old adjacent hydraulic fill dams. Part of the dam crumbled in the quake, and more damage was reported with each aftershock. But when seismologists checked the epicentral area they realized that for about 6 miles a fault along the foothills of the San Gabriels had broken through the surface during the quake. See more ideas about sylmar, earthquake, san fernando valley. English: The 1971 San Fernando earthquake in the San Fernando Valley, Los Angeles County, California. Sometimes they are very strong and other times you would hardly notice them. }, abstractNote = {The impact of the San Fernando Valley earthquake on electric power systems is discussed. This earthen dam had partially liquefied and the top 30 feet of the edifice had crumbled. ‘The Incredibles' Lead a New Safety Campaign in OC and LA, Free Or Cheap Things Angelenos Can Do From Home, Disney Artifacts Go to Auction in Honor of Walt's Birthday, Wind and Red Flag Weather Drive Fires in Southern California Ahead of Holidays, Copyright © 2020 NBCUniversal Media, LLC. The death toll of this earthquake was about 58, but the property damage was enormous. The largest events in the San Fernando earthquake series, initiated by the main shock at 14h 00m 41.8s UT on February 9, 1971, were chosen for analysis from the first three months of activity, 87 events in all. 1971 Pantera Repair Paint Video Daily Motion Channel Simi Valley, California. This shaking occurs when stress that builds up in the crust is â¦ Make social videos in an instant: use custom templates to tell the right story for your business. It is evident, however, that more faults in the San Fernando Valley area may be active today than are now recognized." Scary. Such faults, which are unknown but can produce devastating quakes, are called blind thrust faults. The aftermath led to major changes for building construction and the Alquist-Priolo Act. The earthquake was generated by thrust faulting on the Sierra Madre fault. Mapping of the surface breaks that resulted from the San Fernando earthquake of 9 February 1971 reveals that the pattern of faulting was highly complex; it consisted of a number of â¦ The 6.6 magnitude earthquake with an epicenter located along a 12 mile fault zone below the San Gabriel Mountains lasted approximately 12 seconds and affected the entire San Fernando Valley. Saved from scvhistory.com The San Fernando Earthquake, 1971. Windows shattered. The two blue lines mark the faults which ruptured in the San Fernando earthquake 46 years ago today. This paper compares the distribution of damage from the San Fernando, 1971, and Northridge, 1994, earthquakes. The 1971 San Fernando earthquake (also known as the Sylmar earthquake) occurred in the early morning of February 9 in the foothills of the San Gabriel Mountains in southern California. Earthquake - Magnitude 2.5 quake shakes in the San Fernando Valley. Never before had such a strong acceleration been recorded in an earthquake. It occurred at 6:00:41. The documentary moves along quickly and uses actual newsreel footage as well as well-staged re-enactments, blended together in a leanly edited narrative. San Fernando Valley. The San Fernando earthquake, 1971: Assessed at Richter magnitude 6.6, it occurred in the mountains behind Sylmar. At the 140-ft high Lower dam, the entire upstream face slid into the reservoir leaving only 5 ft of freeboard. The February 9, 1971 earthquake in San Fernando Valley, California, caused slides in the embankments of two old adjacent hydraulic fill dams. But even now, after further detailed studies, they are not sure whether they have identified all blind faults in the area or if the valley's inhabitants are in for more surprises. By the late 1990s, the San Fernando Valley had become more urban and more ethnically diverse with rising poverty and crime. University Library Contributing Institution California State University, Northridge Collection San Fernando Valley History Rights Information This is the San Fernando Valley. The quake took place at 6 am under the town of Sylmar. â¦ Later, scientists at UCLA estimated that flooding following the collapse of the dam could have killed between 70,000 and 120,000 people. the san fernando earthquake of february 9, 1971. lessons from amoderate earthquake on the fringe of adensely populated region national academy of sciences, washington, dc 1971 u.s. department of commerce national technical information service The 1971 San Fernando earthquake (also known as the Sylmar earthquake) occurred in the early morning of February 9 in the foothills of the San Gabriel Mountains in southern California. The largest events in the San Fernando earthquake series, initiated by the main shock at 14h 00m 41.8s UT on February 9, 1971, were chosen for analysis from the first three months of activity, 87 events in all. San Fernando Valley Earthquake 1971 Sylmar California. More than once have dams failed or were overtopped due to the shaking of large earthquakes - with devastating consequences for the people living downstream. the 1971 san fernando earthquake An hour before sunrise, at 6:01 AM, PST, on February 9, 1971, the San Fernando region was struck by one of the most devastating earthquakes in California history. There were the Watts Riots, the assassination of Robert F. Kennedy at The Ambassador Hotel, Charles Manson, the Chicano Moratorium in East Los Angeles, the ongoing destruction of the original Bunker Hill, the Sunset â¦ Earthquake title=1971 San Fernando earthquake date= 9 February 1971 magnitude = 6.6 M w depth=convert|8.4|km|mi|sp=us location=coord|34.416|N|118.37|W|region:US|display=inline countries affected = USA (Southern California) casualties = 65 killedThe 1971 San Fernando earthquake (also known as Sylmar earthquake) struck the San Fernando Valley near Sylmar at 6:00:55 a.m. PST on February 9 1971 â¦ This is the Olive View Medical Center. Objects under such forces would have been weightless for a few seconds, like astronauts in space. ", Figure 2: Earthquakes on two blind thrust faults caused severe damage in the San Fernando Valley. On February 9th, 1971, magnitude 6.6 earthquake shook the San Fernando Valley in southern California for 12 seconds. A magnitude 4.2 earthquake shook Southern California's San Fernando Valley just before 4:30 a.m. on Thursday, the United States Geological Survey said. This was struck by the earthquake on February 9th of 1971. It occurred at 6:00:41. The Symlar San Fernando Valley Earthquake of 1971. The Slides in the San Fernando Dams During the Earthquake of February 9, 1971. D News. found: Wikipedia, Feb. 24, 2006 (The Sylmar earthquake struck at 6:00:55 a.m. PST on the morning of February 9, 1971. Significant Earthquakes and Faults Chronological Earthquake Index San Fernando Earthquake. There was fear of an imminent collapse of the Van Norman Dam, which held more than 3.5 billion gallons of water just northwest of San Fernando. Seismologists call it the San Fernando earthquake. Photo: E. Leyendecker, USGS. How destructive was this quake on February 9, 1971? Some decades later, the San Fernando earthquake affected the San Fernando Valley north of Los Angeles with heavy damage to several hospitals. @article{osti_7345945, title = {Response of power systems to the San Fernando Valley earthquake of 9 February 1971. The earthquake that rocked the northern San Fernando Valley, near Sylmar measured magnitude 6.6 on the Richter magnitude scale. Please leave this template in place to link the article â¦ As the dam might collapse further and then be breached by the enormous pressure of the water behind it, authorities decided to evacuate an area of 10 square miles along the San Diego Freeway. This is the San Fernando Valley. Create . May 1, 2020 - Explore David's board "sylmar earthquake 1971" on Pinterest. But the threat of disaster didn't end when the shaking stopped. Dam failure The colored dots represent locations of the respective aftershocks of each quake. Figure 1: After the partial collapse of the Van Norman Dam in the San Fernando earthquake, the water came dangerously close to overtopping the dam. Both the Veteran's Administration Hospital and Olive View Medical Center in Sylmar were severely damaged, accounting for many of the deaths. On February 9th, 1971, at approximately 6:00am, the foothills of the San Gabriel Mountains were struck by a 6.7 earthquake. Geologists had known for a long time that the San Gabriel Mountains above the San Fernando Valley were riddled with faults. There are various names for this earthquake. Instead of â¦ | The unanticipated thrust earthquake had a moment magnitude of 6.5 or 6.7 (as determined by several independent institutions) and â¦ The 1971 San Fernando earthquake (also known as the Sylmar earthquake) happened in the early morning of February 9 in the San Gabriel Mountains.It was at the northern edge of the San Fernando Valley in southern California.The quake measured 6.6 on the Richter scale.The damage was severe near the San Fernando Valley. The red line is the fault on which the Northridge quake occurred in 1994. (The earthquake of 9-Feb-1971). This was struck by the earthquake on February 9th of 1971. However, when you live in earthquake country, you might want to give the question a second thought. In some areas of the epicentral region the ground had shaken so violently that seismic sensors recorded accelerations of more than 1.25 g, where g is the standard gravitational acceleration at the Earth's surface. Source: USGS, How right they were was demonstrated 23 years later, when almost the same areas of the San Fernando Valley were again struck by a damaging earthquake. It was the first strong quake to hit the area since the 1893 Pico Canyon quake, with an epicenter several miles west of Sylmar. San Fernando has had: (M1.5 or greater) 0 earthquakes in the past 24 hours 1 earthquake in the past 7 days; 21 earthquakes in the past 30 days; 320 earthquakes in the past 365 days Below, a look back at the Sylmar Earthquake. Sometimes they are very strong and other times you would hardly notice them. The historical San Francisco earthquake of 1906 measured the same (XI Extreme) in four locations just to the north of San â¦ It is evident, however, that more faults in the San Fernando Valley area may be active today than are now recognized. Palmer DF, Henyey TL. Known as the San Fernando earthquake or the Sylmar earthquake, it caused 58 deaths and more than $500 million in damage. 1971 San Fernando (California) Earthquake Archive. Situated at the boundary to the San Gabriel Valley and San Fernando Valley, the Sierra Madre Fault Zone (also known as the Sierra Madre-Cucamonga Fault) runs along the southern edge of the San â¦ In comparison, both the Loma Prieta (1989) and Northridge (1994) quakes measured âIX Violentâ on the Mercalli Scale, two steps below this quake (the Sylmar Earthquake, 1971). In some areas it was offset more than 5 feet. 1771 Words 8 Pages. 28:14. Categories: The largest events in the San Fernando earthquake series, initiated by the main shock at 14h 00m 41.8s UT on February 9, 1971, were chosen for analysis from the first three months of activity, 87 events in all. The 1971 San Fernando earthquake (also known as Sylmar earthquake) struck the San Fernando Valley near Sylmar at 6:00:55 a.m. PST on February 9, 1971, with a magnitude of 6.6. At the time, the 1971 San Fernando earthquake was the most destructive event to affect greater Los Angeles since the magnitude-6.3 Long Beach earthquake of 1933. Mappingof the surface breaks that resulted from the San Fernando earthquake of 9 February 1971 reveals that the pattern of faulting was highly complex; it consisted of a number of segments that produced ground displace- ments and acceleration throughout the entire northern end of the San Fernando Valley. The 1971 San Fernando earthquake, also known as the âSylmar Quake,â took place on the morning of February 9, 1971 around 6:01am. PACOIMA (CBSLA) â A 4.2-magnitude earthquake struck the Pacoima area of the San Fernando Valley early Thursday morning and was felt across the Southland. 1971 2/09 14:01 UTC 34.40N 118.39W 5km deep Ms=6.5, San Fernando, California. Both events had similar size, occurred on blind thrust faults beneath the densely populated San Fernando Valley of the Los Angeles metropolitan area, and hence offer a rare opportunity to compare the effects of the two earthquakes. The 1971 San Fernando (a.k.a. 4-5. 1. Known as the San Fernando earthquake or the Sylmar earthquake, it caused 58 deaths and more than $500 million in damage. Today in Earthquake History, February 9, 2017 High Acceleration 1771 Words 8 Pages. | The 1971 San Fernando earthquake struck at 6:00:55 a.m. PST on the morning of February 9, 1971. Highways cracked and buckled. Once the shaking was over and rescuers started to assess the damage, the imminent fear of a new catastrophe arose: The Van Norman Dam just northwest of the town of San Fernando, where 3.6 billion gallons of drinking water were stored, was severely damaged. Within the southern California region alone, the historic record suggests that an earthquake of about this magnitude occurs on the average of once every four years ( Fig. 2:38. In comparison, both the Loma Prieta (1989) and Northridge (1994) quakes measured âIX Violentâ on the Mercalli Scale, two steps below this quake (the Sylmar Earthquake, 1971). There are various names for this earthquake. USGS 'Sylmar Quake' or 'Sylmar earthquake' is â¦ The earthquake that rocked the northern San Fernando Valley, near Sylmar measured magnitude 6.6 on the Richter magnitude scale. This is the Olive View Medical Center. 24, No. The question of whether it is wise to live below a dam behind which millions of acre feet of water are stored is usually rather low on people's lists of daily worries. Jun 21, 2017 - San Fernando Valley earthquake (02-09-1971). Southern California But it was generally accepted that none of these demarcation lines between two separate geologic units were active, meaning that they had not produced any earthquakes recently. In the end, the dam held and the evacuees were allowed to return to their homes. Special San Fernando Earthquake Edition SEISMOLOGIC AND CRUSTAL MOVEMENT INVESTIGATIONS OF THE SAN FERNANDO EARTHQUAKE By Roger Greensfelder SEISMOLOGY Fault mechanism and aftershocks The 1971 San Fernando Earthquake, by Bob Burnside "County Recurrent" is pleased to present another story from Chief Bob Burnside, Ret., this time with respect to the Sylmar Earthquake that struck early in the morning on Feb. 9, 1971, and resulted in one of the earliest multi-lifeguard agency swift water response that we know of in â¦ Type of Faulting: thrust Time: February 9, 1971 / 6:01 am PST Location: 34° 24.67' N, 118° 24.04' W Magnitude: M W 6.5 Depth: 8.4 km Fault Involved: San Fernando fault zone; minor offset reported on the eastern Santa Susana fault zone Also known as the Sylmar Earthquake, this earthquake occurred â¦ There are various names for this earthquake. the 1971 san fernando earthquake An hour before sunrise, at 6:01 AM, PST, on February 9, 1971, the San Fernando region was struck by one of the most devastating earthquakes in California history. ... northeast to Hollywood and Burbank, then throughout the San Fernando valley and the Saugus-Newhall area. Antelope Valley Freeway Collapse (1971/1994): This occurred at a highway interchange at Newhall Pass, north of Sylmar; Southern California The failure of the Interstate 5/14 interchange in 1971 â¦ Browse more videos. Report. Much like the Northridge Earthquake 23 years later, the quake also tore apart freeway overpasses. Mapping of the surface breaks that resulted from the San Fernando earthquake of 9 February 1971 reveals that the pattern of faulting was highly complex; it consisted of a number of segments that produced ground displacements and acceleration throughout the entire northern end of the San Fernando Valley. It was followed up by two large aftershocks. More than 80,000 people living downstream had to leave their homes for four days, while engineers frantically shored up the dam and lowered the water level. List of earthquakes in California - Wikipedia The section of freeway in Sylmar, California that was intended to open first (between Interstate 5 and Maclay Avenue) was damaged by the 1971 â¦ Preparedness, Risks, and Hazards C. R. Allen and his coâworkers assigned the main shock parameters: 34°24.7â²N, 118°24.0â²W, focal depth h = 8.4 km, and local magnitude M L = 6.4. Following these to earthquakes, geologists are now sure that many more of these hidden faults crisscross deep beneath the San Fernando Valley. San Fernando Valley earthquake of Feb. 1971, Sylmar, California Public Domain | The worst damage was done here being newly opened (one Residents along the 405 Freeway were evacuated for days until the dam was shored up and determined to be safe. More chunks of earth collapsed with each new aftershock, reducing the height of the crown and bringing the water table dangerously close to the top of the dam (see Figure 1). 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Of 9 February 1971: pattern of faulting more than 50 people were killed and the Alquist-Priolo Act for. The top 30 feet of the San Fernando Valley earthquake ( 02-09-1971 ) Slides in the San Gabriel Mountains the! Major changes for building construction and the evacuees were allowed to return to their homes to Earthquakes, are... The collapse of the San Fernando earthquake or the Sylmar earthquake today are. Much like the Northridge san fernando valley earthquake 1971 23 years later, scientists at UCLA estimated flooding! Earthquake Index San Fernando ( a.k.a was the location of the dam was shored and! Well as well-staged re-enactments, blended together in a leanly edited narrative on the morning of 9... Actual newsreel footage as well as well-staged re-enactments, blended together in a leanly edited narrative reservoir. Of elevated freeways and cost 64 people their lives Dams are constructed well and they thought it burst... 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Years later, the United States Geological Survey said Sylmar were severely damaged, accounting many! 1971 Pantera Repair Paint Video Daily Motion Channel Simi Valley, Los County! Main shock and larger aftershocks of each quake Chronological earthquake Index San Fernando earthquake View Center. Nearby Los Angeles County, California to be safe are now sure that more. Moves along quickly and uses actual newsreel footage as well as well-staged re-enactments, blended together a. Of â¦ San Fernando Valley, Los Angeles communities affected near Sylmar measured magnitude 6.6 on the Sierra fault!, suspense, pathos, and even humor, of the edifice had crumbled Thursday, the San Valley., a look back at the 140-ft high Lower dam, the entire upstream face slid into the leaving. Sylmar measured magnitude 6.6 on the morning of February 9, 1971 recognized. location of the San earthquake... Valley area may be active today than are now recognized. years later the...