Interim report on worldwide historic surface faulting

This interim report presents data on and interrelations between the parameters L (length of surface rupture), D (maximum surface displacement), and M (Richter magnitude of associated earthquake) for the main traces of historic surface faults that have been reported in the worldwide literature. Original descriptions of the individual fault-events published in English, French, German, or Spanish were used whenever possible, supplemented by translations of selected passages of reports published in Japanese and Chinese. For some events, original descriptions were not published in these languages and secondary sources were used. Although more than 100 fault-events have been reported in the literature, only those for which reliable data (in the judgement of the present writers) were available on at least two of the three parameters M, L, and D are included in this interim report and listed in table 1. Some fault-events have been omitted because the available reports contained significantly different data for the same event and the writers had insufficient basis for choosing between them.

This report was prepared to permit early release of part of the results of a more comprehensive study of historic surface faulting now under way, and to elicit suggestions and criticisms from users of the report. Comments are especially invited regarding the methods used in designating the fault type and in identifying the main fault.

The more comprehensive report will deal with subsidiary faults as well as main faults, will have detailed citations of the sources of information, and will discuss various additional aspects of faulting. It is anticipated that reliable data on a few more faults will be obtained, and it is hoped that comments from users of this interim report will permit improvement of the comprehensive report. Thus it is expected that the comprehensive report will contain modifications of the present data and will be of larger scope.