1993年全球地震活动综述

OVERVIEW OF THE GLOBAL SEISMICITY IN 1993

根据国家地震局地球物理研究所编制的《中国地震台临时报告》的初步资料和美国地质调查局编印的《ＰｒｅｌｉｍｉｎａｒｙＤｅｔｅｒｍｉｎａｔｉｏｎｏｆＥｐｉｃｅｎｔｅｒｓ》月报，整理出１９９３年全球６级以上地震目录，并画出１９９３年１－１２月全球及中国大陆地震活动性指数Ａ（ｂ）值曲线。１９９３年全球地震活动水平初步评定为中等偏高；全球地震活动中心在太平洋西北边缘地震带，共发生Ｍ＿ｓ７．６地震两次。全球地震活动最高月份为９月，中国大陆地震活动最高月份为１０月。三次最大地震分别是：７月１２日的日本北海道西南近海地震，８月８日的马里亚纳群岛以南（关岛）地震，９月１０日的墨西哥恰帕斯州近海地震。

On the basis of data from the“Preliminary Seismological Report of Chinese SeismicStations”and the “Preliminary Determination of Epicenters”of the USGS,the author of this pa-per has compiled the catalogue of the 1993 global earthquakes with M≥6 and has drawn up thecurves of A(b) values of the global and the Chinese mainland seismicities for January-December1993.The 1993 global seismicity was preliminarily evaluated to be of medium level or slightlyhigher; the center of the global seismicity was on the northwest marginal seismic zone of the Pa-cific,where two quakes of M_s7.6 occurred.The global seismicity was highest In September,andseismicity in the Chinese mainland was highest in October.The three largest earthquakes are asfollows:the July 12 earthquake near the southwest coast of Hokkaido;the August 8 earthquakestriking south of the Mariana Island(Guam);and the September 10 earthquake off the coast ofChiapas,Mexico.