Phenomenon of local 'seismic reversal' before strong earthquakes

We explore here the following hypothetical phenomenon: the territorial dist ribution of low-magnitude seismicity is reversed within several months prio r to a strong earthquake in the area, surrounding its source; the diameter of this area is on the order of 100 km. This phenomenon is investigated for the Lesser Antilles and southern California. On that basis, we suggest a h ypothetical earthquake prediction algorithm to be tested by advance predict ion. Retrospective application of the algorithm and the first three years o f advance prediction in Lesser Antilles give encouraging results. In compar ison with well-known intermediate-term prediction algorithms M8, CN, and Me ndocino Scenario, the SR algorithm gives smaller time-space areas of the al arm. It has a serious disadvantage, however; the catalogue should be comple te for a longer period of time and for smaller magnitudes, than are require d in CN and M8. (C) 1999 Elsevier Science B.V. All rights reserved.