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The California Earthquake Advisory Plan: A history

May 1, 2017

Since 1985, the California Office of Emergency Services (Cal OES) has issued advisory statements to local jurisdictions and the public following seismic activity that scientists on the California Earthquake Prediction Evaluation Council view as indicating elevated probability of a larger earthquake in the same area during the next several days. These advisory statements are motivated by statistical studies showing that about 5% of moderate earthquakes in California are followed by larger events within a 10-km, five-day space-time window (Jones, 1985; Agnew and Jones, 1991; Reasenberg and Jones, 1994). Cal OES issued four earthquake advisories from 1985 to 1989. In October, 1990, the California Earthquake Advisory Plan formalized this practice, and six Cal OES Advisories have been issued since then. This article describes that protocol’s scientific basis and evolution.

Publication Year 2017
Title The California Earthquake Advisory Plan: A history
DOI 10.1785/0220160183
Authors Evelyn A. Roeloffs, James D. Goltz
Publication Type Article
Publication Subtype Journal Article
Series Title Seismological Research Letters
Index ID 70192471
Record Source USGS Publications Warehouse
USGS Organization Earthquake Science Center