Ground Rupture in the Baldwin Hills

Ground Rupture in the Baldwin Hills, Injection of fluids into the ground for oil recovery and waste disposal triggers surface faulting by Douglas H. Hamilton and Richard L. Meehan, April 23, 1971, Science Vol 172, No 3981
Consequences of the disaster were minimal compared with what would have occurred had no warning been provided, but they included five lives lost, $12 million in property damage, and loss of the reservoir itself. The remains of the Baldwin Hills Reservoir stand empty today…. A linear crack issuing from the base of this gap can be traced across the asphalt floor of the reservoir. It reappears as a slight buckling of road pavement on the far side of the reservoir basin and thence becomes a faint, discontinuous break in the ground surface, which trails off south of the reservoir into the brush-covered and excavation scarred terrain of the Inglewood Oil field. … Two lawsuits filed in 1966 by the city and its insurers against the oil companies active in the Inglewood oil field at the time of the dam failure charged that the oil field operators had led to the events directly associated with breaching of the dam. These suits were settled out of court for $3.9 million dollars, thus disposing of the immediate financial issues that arose from the ground rupturing beneath the reservoir. Origin of the ruptures is a question that remains unadjudicated. … Conclusions That the earth-crack ground rupturing of the Baldwin Hills was genetically related to high-pressure injection of fluid into the previously faulted and subisdence-stressed subsurface seems established before reasonable doubt. The fault activation appears to be a near-surface manifestation of stress-relief faulting triggered by fluid injection, a mechanism identified as being responsible for the 1962-65 Denver earthquakes and for generation of small earthquakes at the Rangely oil field in western Colorado (20). These examples of fault activation through the response of stressed ground to artificially induced increases in subsurface fluid pressure demonstrate some of the mechanically predictable consequences of injection of fluid into the ground, a practice that is becoming increasingly widespread not only in secondary oil-recovery operations but as a means of industrial waste disposal and groundwater management. Experience in the Baldwin Hills suggests that, although fluid injection operations may be carried out for beneficial purposes, the effects of such injection on the geologic fabric can be serious and far-reaching.