Big Bear Lake, CA, June 28, 2012, 8:35am – At 04:57 in the morning 20 years ago today on June 28, 1992, a large quake awoke much of Southern California. It was the Landers Earthquake. During the 7.3 quake the ground shook for two to three minutes in what was described as a right-lateral strike-slip event. By the time it was over the rupture of 5 different faults of a length over 53 miles had occurred. The shaking that morning was far from over for Big Bear residents. Three hours and eight minutes later the Big Bear earthquake began measuring 6.5 on the Richter scale and an 8 on the Mercalli intensity scale. Although 3 people died as a result of Landers, two heart attacks and one child killed by falling chimney bricks, Big Bear was spared such casualties. Weakened masonry chimneys in Big Bear fell over perhaps due to timing and proximity of the Landers quake just 22 miles to the east or perhaps because of the nature of our older Big Bear structures. Regardless, the damage in one fashion or another affected every building in the Big Bear valley. At first, the USGS thought the Big Bear quake was an aftershock of the Landers quake but later confirmed that it was part of a separate regional earthquake sequence. Further, it was concluded that because the San Andres fault is significantly close these quakes might have reduced the pressure on the great California fault. According to a press release form the USGS today they are marking the 20th anniversary of these major earthquakes by bringing together local elected officials, police and fire officials, and emergency and city managers to learn from USGS scientists about the latest tools and resources to help plan for and respond to a major earthquake. KBHR suggests that today may be time to dust off your personal emergency plans and to stock your home emergency pack with updated items.
