May 17, 2009 Los Angeles Earthquake

Posted by Alexandra Matiella Novak May 18, 2009

Residents of Southern California were jolted Sunday night as a 4.7 earthquake with an epicenter 3 miles east of Los Angeles International Airport occurred. Because the earthquake happened in a populated urban area, many reports were sent into the USGS Did You Feel It? website. Residents living in Carson, Long Beach and Compton reported feeling moderate shaking. Residents living near the epicenter reported feeling light shaking. Californian's reported feeling the earthquake as far north as Bakersfield and as far south as San Diego. The USGS even recieved some reports from residents in Arizone, New Mexico and Nevada.

Geologists have determined that the fault responsible for the earthquake was the Newport-Inglewood fault. This fault is also responsible for the 1933 Long Beach earthquake. The fault was orginally identified because of a magnitude 4.9 earthquake in 1920 that had an epicenter very similar in location to the May 17 earthquake and for that reason was named the Inglewood fault. After the 1933 earthquake, geologists were able to determine that the fault ran continuously from Beverly Hills to Newport Beach, so renamed the fault the Newport-Inglewood fault.

Although along the same fault, the epicenter of the 1933 Long Beach earthquake was offshore. This earthquake caused $40 million in property damage and killed 115 people. Most alarmingly, many school building were completely destroyed, but because of the time the earthquake occurred - 5:55 pm PST - were uninhabited. Because of this, the earthquake initiated the 1933 Field Act, which was passed by the California State Legislature. The Field Act required public buildings, especially schools, to be earthquake resistant. This earthquake also initiated studies in earthquake engineering to avoid future hazards to Southern Californians.