Date: July 21, 1952
Location: Kern County, Ca
The Kern Country earthquake was the largest experienced in the United States after the 1906 quake in San Francisco. There was a significant amount of damage caused by the earthquake. It resulted in the loss of 12 lives and approximately $60 million worth of property damage. The area where the earthquake hit was southeast of Bealville on the Southern Pacific Railroad and an MM intensity of XI was assigned to the area.
Damage to Lives and Property
The effects of the disaster included the following: cracked tunnels with walls 46 centimetres thick made with reinforced concrete; shortened distance between two tunnel portals by 2.5 meters and twisted train rails into the curves with an S-shape. Damage was also caused 160 kilometres from the epicentre as brine lines were twisted into S-shapes and salt beds were shifted. The tremendous power of the earthquake was evident in its impact on Bear Mountain which showed a series of surface ruptures. The surface ruptures were noted in the White Wolf Fault Zone. The valley with its badly integrated alluvium showed erratic cracks and was reconfigured to a great extent. It is apparent that Bear Mountain itself moved up in a northward direction. Damage was caused in the San Joaquin Valley that was situated southwest of Arvin. The ground cracked and led to the partial collapse of a residence due to its concrete foundation splitting. There was slumping and caving of the ground which led to cotton rows being moved by over 30 centimetres and the pavement of a highway crumpling by over 300 meters. Further damage was noted east of Caliente where a huge crack was seen. The crack was over 60 centimetres deep and approximately 1.5 meters wide at its largest point. Damage was observed on the State Highway 58 which was then called U.S. Highway 466. A large part of the highway was cracked and crushed and in the mountainous regions of the highway, fill areas moved a few centimetres in certain places and up to 30 centimetres in the most affected areas. Ground northeast of the highway was displaced by approximately 60 centimetres vertically and approximately 45 centimetres horizontally. There was significant property damage in several populated cities and damages were noted in Arvin, Bakersfield and Tehachapi. Poorly built buildings and adobe constructions were cracked and some collapsed.
Tehachapi was one of the hardest hit cities and many of its brick and adobe building were affected. There was also a significant loss of life in the city due to the earthquake and 9 people were killed. A total of 3 people were killed in the other cities that were affected by the earthquake.
Bakersfield was not as badly affected as the other cities and the majority of the damage was limited to parapet failure. Many brick building were cracked and older buildings were damaged. In contrast to the relatively moderate damage in the city, the Kern County General Hospital was severely damaged. Many high rise structures made with steel and concrete sustained damage mainly on the first floor. The property damage caused in Arvin was similar to that caused in Bakersfield.
Long Period Wave Effects
The long period wave effects of the Kern County earthquake were widespread and was reported from as far away as Los Angelis were non-structural damage to tall building was observed and water splashed in swimming pools. Similarly, in the San Francisco area, water splashed in pressure tanks that were on top of tall buildings. One building sustained damage in San Diego. Furthermore, a building under construction in Las Vegas, Nevada required realignment of the structural steel. The shock of the quake was felt in parts of western Nevada, western Arizona, California, Sterling City and Phoenix. Furthermore, aftershocks were recorded by the California Institute of Technology in Pasadena. Accordingly, 188 4.0 or higher aftershocks were recorded.
However, in comparison to the Long Beach earthquake of 1933, it can be concluded that property damage was not quite as severe in the Kern County earthquake of 1952. While the Long Beach earthquake threw many buildings off their foundations, the Kern County earthquake mainly caused serious damage to wood frame structures.