A little known fact was that the van norman dam was. San fernando valley sylmar earthquake 1971 youtube. San fernando earthquake 1971 today in history 9 feb. 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. Earthquakes on two blind thrust faults caused severe damage in the san fernando valley. The division of earth sciences there fore established the joint panel on the san fernando earth quake to draw from the event and its effects.
A nonlinear effective stress finite element approach for dynamic analysis of soil structure is described in. Oct 01, 2009 the 1971 san fernando earthquake also known as sylmar earthquake struck the san fernando valley near sylmar at 6. Did the zones with severely damaged buildings reoccur. The unanticipated thrust earthquake had a moment magnitude of 6. Because of the magnitude of the slide and strong interest of the engineering profession in the evaluation of the seismic stability of earth dams, the lower san fernando dam slide has received. San fernando, california, earthquake of february 9, 1971. Also known as the sylmar earthquake, this earthquake occurred on the san fernando fault zone, a zone of thrust faulting which broke the surface in the sylmar san fernando area. Hileman seismological laboratory, california institute of technology pasadena, california 91109 the largest events in the san fernando earthquake series, initiated by the main. Earthquakeinduced deformation analyses of the upper san. Download a pdf of san fernando earthquake of february 9, 1971 by the national research council for free. An extensive summary of the worldwide standardized seismograph network, including detailed description of all wwssn stations.
The san fernando earthquake has been extensively studied by many seismologists, geologists, and earthquake engineers. San fernando, california, earthquake of february 9, 1971 united states. The former pages 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. This was an after shock of the feb 9th 1971 earthquake. Fernando, california, earthquake february 9, 1971, ml. The colored dots represent locations of the respective aftershocks of each quake. The two blue lines mark the faults which ruptured in the san fernando earthquake 46 years ago today. San fernando, california earthquake engineering research. Presented also are the most widely accepted methods for evaluating the liquefaction potential of cohesionless oils in level ground, for estimating earthquake induced settlements and.
Article from the february 1971 newsletter pdf other reports. Severe damage of the dam during the 1971 san fernando earthquake forced residents to evacuate homes in a 6milelong area down the valley. Evidence is presented which suggest that the 1971 san fernando earthquake may have been a double event that occurred on two separate, subparallel thrust faults. Nearby lower san fernando dam was damaged even more severely, and would have probably led to an uncontrolled release if the reservoir elevation had not been restricted prior to the earthquake. Before the 1971 san fernando earthquake early media reports refer to this event as the sylmar earthquake while seismologists use the name san fernando earthquake, it was assumed that operational loads on bridges presented more severe structural requirements for. The largest events in the san fernando earthquake series, initiated by the main shock at 14h 00m 41. Jul 9, 20 1971 sylmar earthquake san fernando valley lived through this quake on feb. The death toll of this earthquake was about 58, but the property damage was enormous. Before the 1971 san fernando earthquake early media reports refer to this event as the sylmar earthquake while seismologists use the name san fernando earthquake, it was assumed that operational loads on bridges presented more severe structural requirements for bridges than did 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. The san fernando, california, earthquake of february 9, 1971. The collapse of curved overpass was due to seismic shaking and to lateral extension of the north and south abutments thereby shortening the chord. Engineering features of the san fernando earthquake of. San fernando earthquake conference 50 years of lifeline. The 1971 san fernando earthquake occurred in the early morning of february 9 in the foothills of the san gabriel mountains in southern california. San fernando earthquake series, 1971 focal mechanisms. The quakes epicenter was located five miles north of the san fernando valley, near the. The damage was severe near the san fernando valley. The red line is the fault on which the northridge quake occurred in 1994.
The recently completed freeway interchange in the north san fernando. Examples of such catastrophes include the 1964 alaska earthquake, the san fernando earthquake of 1971, the guatemala earthquake in 1976, the 1987 ecuador earthquake, the kobe earthquake in 1995, and the 2003 algeria earthquake. San fernando, california, earthquake of 9 february 1971. Earthquake reconnaissance and effects on structures 1971 san fernando or sylmar earthquake oblique air view southeast of collapsed structures at interchange of highways 5 and 210. Geological survey and the national oceanic and atmospheric administration.
Earthquake reconnaissance and effects on structures. The 1971 san fernando earthquake, also known as sylmar earthquake, struck the san fernando valley near sylmar at 6. Wentworth, et al and a great selection of related books, art and collectibles available now at. San fernando dam during the 1971 san fernando earthquake in california, just to name a few. The quake ripped open the surface for about 12 miles in the mountains and san fernando valley, knocked down parts of the sfv veterans hospital and. The 1971 san fernando earthquake also known as the sylmar earthquake happened in the early morning of february 9 in the san gabriel mountains. Please leave this template in place to link the article histories and preserve this attribution. Knowledge gained from this event initiated the study of lifeline systems worldwide, including water, wastewater, electric power. The faulting mechanism of the san fernando earthquake. Southern california earthquake data center at caltech. Engineering aspects of the 1971 san fernando earthquake. Front matter san fernando earthquake of february 9, 1971. The unanticipated thrust earthquake had a magnitude of 6. San fernando earthquake an overview sciencedirect topics.
It was at the northern edge of the san fernando valley in southern california. Seismograms of the 1971 san fernando california earthquake. In the san fernando earthquake, the number of deaths 65, of people sustaining serious injuries over 1,000 and amount of major structural damage was almost entirely confined to portions of san fernando and tujunga valleys, and the newhallsaugus area map, page 62. The san fernando earthquake of february 9, 1971 in southern california initiated a major slide on the downstream slope of upper san fernando dam. Pdf the response of veterans hospital building 41 in the san. The effect on state highways of the san fernando earthquake, february 9, 1971 california. Material from 1971 san fernando earthquake was split to sierra madre fault zone on 23. Survey of japanese design requirements for bri dges. Special san fernando earthquake edition the 1971 san fernando earthquake an hour before sunrise, at 6. Later known as the san fernando earthquake, the quake was responsible. Statements to the joint legislative committee on seismic safety and its subcommittee on the san fernando earthquake february 9, 1972 geological and seismological lessonssubmitted by allen pdf. Because of its consequences, the san fernando earthquake was a major earthquake from the engineering point of view, even though it was only a moderate shock in seismological terms. The february 9, 1971 san fernando california earthquake was a devastating yet seminal event which, for the first time, demonstrated the seismic threat to lifelines that fundamentally support our modern livelihoods. After the partial collapse of the van norman dam in the san fernando earthquake, the water came dangerously close to overtopping.
Sylmar got its name on the event, but the epicenter was deep under the san gabriel mountains, in the san fernando fault zone. Relation of known faults to surface ruptures, 1971 san fernando. San fernando earthquake series, 1971 focal mechanisms and tectonics james h. Eeri preliminary engineering findings report pdf newsletter articles. In comparison, both the loma prieta 1989 and northridge 1994 quakes measured ix violent on the mercalli scale, two steps below this quake the sylmar earthquake, 1971. Lessons from a moderate earthquake on the fringe of a densely populated region. The san fernando earthquake, 1971 video dailymotion. Search for library items search for lists search for contacts search for a library. We evacuated because the van norman dam was cracked, and they thought it. Teleseismic p, sv, and sh waves recorded by the wwss and canadian networks from the 1971 san fernando, california earthquake ml 6. San fernando, california, earthquake of 9 february 1971 by oakeshott, gordon b. The san fernando, california, earthquake of february 9. San fernando california earthquake february 9 1971 abebooks.
Check out the record album the radio station mad from that day. It is postulated that the initial event took place at depth on the sierra madre fault zone which runs along the base of the san gabriel mountains. As a result of the many effects of the earthquake, a large number of detailed studies and reports will be forthcoming from a wide variety of sources, and the papers collected in this volume are only preliminary. Analysis of the pacoima dam accelerogramsan fernando. Request pdf 1971 san fernando and 1994 northridge, california, earthquakes. Feb 22, 2016 on february 9th, 1971, at approximately 6. The earthquake that rocked the northern san fernando valley, near sylmar measured magnitude 6. This paper compares the distribution of damage from the san. Mar 06, 2016 on february 9th, 1971, at approximately 6. A preliminary report by reuben kachadoorian, arthur grantz, carl m. Pdf elastic finitedifference modeling of the 1971 san. A study of source finiteness in teleseismic body waves bulletin of the seismological society of america an exact solution for a finite, twodimensional moving dislocation in an elastic halfspace with application to the san fernando earthquake of 1971. Simple dislocation fault models of the san fernando, california, earthquake of 1971 as deduced from leveling data have been presented with emphasis on an abrupt change in dip angle of fault plane.
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