李钦祖, 刁桂苓, 陈敬伟, 于利民, 孙佩卿. 中南美洲地区地震序列的特征[J]. 华北地震科学, 1998, 16(4): 1-9.
引用本文: 李钦祖, 刁桂苓, 陈敬伟, 于利民, 孙佩卿. 中南美洲地区地震序列的特征[J]. 华北地震科学, 1998, 16(4): 1-9.
Li Qinzu, Diao Guiling, Chen Jingwei, Yu Limin, Sun Peiqing. FEATURE OF THE EARTHQUAKE SEQUENCES OF CENTRAL-SOUTH AMERICA[J]. North China Earthquake Sciences, 1998, 16(4): 1-9.
Citation: Li Qinzu, Diao Guiling, Chen Jingwei, Yu Limin, Sun Peiqing. FEATURE OF THE EARTHQUAKE SEQUENCES OF CENTRAL-SOUTH AMERICA[J]. North China Earthquake Sciences, 1998, 16(4): 1-9.

中南美洲地区地震序列的特征

FEATURE OF THE EARTHQUAKE SEQUENCES OF CENTRAL-SOUTH AMERICA

  • 摘要: 共搜集到1960~1990年中、南美洲地区10个地震序列。其中1个是板内地震序列。这个板内地震序列表现出的特征是:震中分布区域的长轴较短,长短轴之比低;余震震源机制和主震震源机制相比变化大。其余9个是俯冲带上的板缘地震序列,它们的共同特征是:震中分布区域的长轴较长;震源深度下限超过地壳,可以达到70km以下(第10号序列例外);主震的震源机制受俯冲带的走向、倾向和倾角的控制。但是这些地震序列又分为两种情况:(1)有5个地震序列,其震中分布区域的长轴走向和俯冲带的走向相同;(2)有4个地震序列,其震中分布区域的长轴走向和俯冲带俯冲方向相同,即和俯冲带的走向垂直。前者的特征是;震中分布区域的长短轴之比高;余震震源机制和主震震源机制相比除了序列初期的个别地震外,差异甚小。而后者的情况比较复杂,有些地震序列震中分布区域的长短轴之比低,个别地震序列后期余震震源机制和主震震源机制的差别大。

     

    Abstract: The location data of 10 earthquakes sequences of central-south America for the period 1960-1990 are collected. One of them is intraplate earthquake sequence and showed the feature:the major axis of the epicenter area is shorter, the ration of the major axis to minor axis is small. The other 9 sequences are interplate earthquake sequences occurred in the subduction zone and showed the common feature:the major axis of the epicenter area is longer, the depth of focus is 70km at most and is in the medium below crust(with the exception of the sequence No. 10), the fault plane solution of main shock in each scquence is controlled by the strike and dip of subduction zone. These sequences can be divided into two groups:group 1 includes 5 sequences of which the direction of major axis of the epicenter area is parallel to the strike of the subduction zone;group 2 includes 4sequences of which the direction of major axis of the epicenter area is perpendicular to the strikes of the subduction zone. For each sequence of group 1, ratio of the major axis of the epicenter area to the minor axis is larger;fault plane solutions of all aftershocks but a few early ones are not significantly different from that of the main shock. For group 2, ratio of the major axis of the epicenter area to the minor axis of some sequences is less;fault plane solutions of later aftershocks of a few sequences are significantly different from that of the main shock.

     

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