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研究了希腊西部1983年1月1日至1994年12月31日期间SES(VAN法的震电信号)的特征与地震参数间的可能相关。在这一期间,约阿尼纳(IOA)和皮尔戈斯(PIR)VAN台站的所谓选择性图地区,总共有55次m_b≥5.0的地震。对其中的29次地震获得了矩心矩张量解;在IOA台18次地震之前有震电信号,而在PIR台则有11次。这些地震没有1次在发生之前在2个台站同时都有震电信号。本文的主要结果如下:(1)在IOA台站震电信号矢量的方向与所预报地震的震源位置有关,尽管邻近的地震经常有矢量方向不同的震电信号。(2)在IOA台29次地震中的9次逆冲型地震都观测到了震电信号,但它们的矢量方向不是唯一的。(3)在PIR台观测到的凯法利尼亚至伯罗奔尼撒以西地区震前有震电信号的11次地震具有法向分量度不同的走滑型。这些地震在PIR台震电信号的矢量方向主要是向西的。(4)1987年年底上述地区的震源机制从主要为走滑型变为逆冲型,这与敏感地点从PIR台转移到IOA台一致,说明震源机制与VAN台站的选择性特征间可能相关。
The possible correlation between the characteristics of SES (Seismic VAN signal) and seismic parameters during the period from January 1, 1983 to December 31, 1994 in western Greece was studied. During this period, a total of 55 earthquakes of m_b ≥ 5.0 were reported in the so-called selective map area of VOA stations in Ioannina and Piros (PIR). A centroid moment tensor solution was obtained for 29 of these earthquakes; there were seismoelectric signals before 18 earthquakes on the IOA platform, and 11 on the PIR platform. None of these earthquakes occurred at the same time before the earthquake occurred at both stations. The main results of this paper are as follows: (1) The direction of the vector signal of the earthquake at IOA station is related to the location of the hypocenters of the predicted earthquakes, although the earthquakes with different vector directions often occur in the adjacent earthquakes. (2) Seismic signals were observed in all nine thrust earthquakes during the 29 earthquakes on IOA, but their vector directions were not unique. (3) Eleven earthquakes with pre-earthquake earthquakes observed in the PIR platform west of Kefalonia to the Peloponnese region have different types of strike-slip with different normals. These earthquakes are mainly westward in the vector direction of the PIR seismic signals. (4) The focal mechanism at the end of 1987 changed from mainly slippery to thrust-type, which is consistent with the transfer of sensitive sites from the PIR platform to the IOA platform, indicating that the focal mechanism may be related to the selective features of VAN stations .