上海地区地磁转换函数变化及其与近震的关系
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摘要
计算分析了上海地区佘山台１９７７年１月－１９８６年１２月和崇明台１９８３年１月－１９８９年９月的地磁周期Ｔ＝９—２００ｍｉｎ的复转换函数Ａ的模｜Ａ｜、总方差σｚ和帕金森矢量或韦氏矢量，并将其在上海地区９０—３００ｋｍ范围内４次５—６级近震发生时的变化进行了研究．结果表明周期为１５、２０和３５ｍｉｎ的｜Ａ｜和σｚ值在震前有明显异常，帕金森矢量或韦氏矢量在震前指向震中，震后回到正常位置。在此基础上，对１９９０年２月１０日江苏常熟地震作了较成功的预报。并提出地磁转换函数还与灾害性天气有关，在某种程度上增加了提取震磁信息的难度。
The consecutive monthly variations of the transfer functions A of geomagnetic field in the periods T=9-200 min. at Sheshan Observatory from Jan. of 1977 to Dec. of 1986 and those at Chongming Observatory from Jan. of 1983 to Sep. of 1989 as well as the total variance σz and the magnetic azimuth αp were calculated and analysed. Their anomalous changes at four local earthquakes with magnitude 5-6 occurring with 90-300 km epicentral distant from the Shanghai area were studied. The results showed that in the periods T=15, 20 and 35 min. the |A| and σz values were strikingly anomalous prior to the quakes. The parkinson or wiess vectors pointed to the epicenters prior to earthquakes, but returned to their normal positions after the earthquakes. Based on the analysis and strdy of past events, authors of this paper made a fair successful formal prediction in the three elements of time, place and magnitude for the M=5. 4 earthquake occurring on Feb. 10, 1990 in Changshu. The authors found that geomagnetic transfer functions changed anomalously not only related to earthquakes but also weather disasters.
The consecutive monthly variations of the transfer functions A of geomagnetic field in the periods T=9-200 min. at Sheshan Observatory from Jan. of 1977 to Dec. of 1986 and those at Chongming Observatory from Jan. of 1983 to Sep. of 1989 as well as the total variance σz and the magnetic azimuth αp were calculated and analysed. Their anomalous changes at four local earthquakes with magnitude 5-6 occurring with 90-300 km epicentral distant from the Shanghai area were studied. The results showed that in the periods T=15, 20 and 35 min. the |A| and σz values were strikingly anomalous prior to the quakes. The parkinson or wiess vectors pointed to the epicenters prior to earthquakes, but returned to their normal positions after the earthquakes. Based on the analysis and strdy of past events, authors of this paper made a fair successful formal prediction in the three elements of time, place and magnitude for the M=5. 4 earthquake occurring on Feb. 10, 1990 in Changshu. The authors found that geomagnetic transfer functions changed anomalously not only related to earthquakes but also weather disasters.
引文
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