NPR | Early 20th Century Earthquakes May Have Been Caused By Calif. Oil Boom NPR A new study suggests some Los Angeles-area earthquakes in the 1920s and 1930s could have been caused by the oil boom at the time. The paper, scheduled to be published online Tuesday in the Bulletin of the Seismological Society of America, presents ... Oil drilling may have caused deadly 1933 earthquake in Los Angeles, study finds Southern California's deadliest quake may have been caused by oil drilling, study says Oil Production Could Have Caused Century-Old California Earthquakes |