Was the M_w 7.5 1952 Kern County, California, earthquake induced (or triggered)?

Area of Science:

• Seismology
• Earthquake Engineering
• Petroleum Geology

Background:

• Oil production and wastewater injection have been linked to induced seismicity in oil-producing regions.
• The 1952 Kern County earthquake (Mw 7.5) occurred near the Wheeler Ridge oil field.

Purpose of the Study:

• To investigate the potential causal relationship between oil production and the 1952 Kern County earthquake.
• To explore a mechanism by which oil production could induce significant seismic events near major faults.

Main Methods:

• Analysis of spatial and temporal proximity between oil production and the earthquake.
• Development of an analytical model incorporating industry stratigraphic data and poroelastic stress changes.
• Simulation of fault behavior under production-induced stress variations.

Main Results:

• The mainshock occurred 98 days after initial oil production began.
• A model demonstrated how an impermeable splay fault could prevent normal pore pressure dissipation.
• Poroelastic stress changes from production could destabilize the White Wolf fault (WWF).

Conclusions:

• Oil production at Wheeler Ridge is a plausible trigger for the 1952 Kern County earthquake.
• A blocked pore pressure pathway is a key factor in production-induced seismicity near major faults.
• This mechanism explains why large earthquakes are not commonly induced by production near major faults.