1992-06-28 Landers Earthquake and Aftershocks

Last updated: 2014-10-13 21:29:13 UTC

Introduction

A collaborative study to record aftershocks was undertaken by several Southern California Earthquake Center (SCEC) institutions following the June 28, 1992 Landers and Big Bear earthquakes. The Mw 7.6 Landers earthquake occurred at 04:58 PDT approximately 10km north of Yucca Valley along the southern extension of the Johnson Vallet fault. The earthquakes produced over 70km of ground rupture, with cumulative right-lateral offsets of 3 - 6.5m along segments of the Homestead Valley, Emerson Lake, and Camp Rock faults, all of which were involved in the sequence.

The primary aftershock activity occurred in a narrow band from 33.6°N, -116.2°W north to 34.5°N, -116.6°W, with a separate cluster at 35.0°N, -117.0°W. The Mw 6.5 Big Bear earthquake occurred at 08:04 PDT approximately 35km west of the Landers epicenter in the San Bernadino Mountains, involving left-lateral slip on a fault that strikes N45W and dips 70SE. The Big Bear aftershocks occur over an area about 30km long, extending northeast from 34.1°N, -117.0°W to 34.4°N, -116.6°W.

URL: http://eqinfo.ucsd.edu/special_events/1992/180/a/index.php [Last updated: 2014-10-13 21:29:13 UTC]