台湾琉球地区Lg波的震相特征
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摘要
根据浙闽台站记录的台湾琉球近震资料，研究了该区Ｌｇ波的组成及各震相的基本特征。研究表明，该区Ｌｇ波由多个速度不同的波群组成，在Ｌｇ１和Ｌｇ２两种波中可以分出Ｌｇ′１、Ｌｇ″１；和Ｌｇ′２、Ｌｇ″２四种震相，不同震区各震相的记录特征明显不同，鲜明地反映出地壳结构由大陆型向海洋型过渡的特点。此外，还对波列中的未知震相、影响震相记录特征的其它因素，以及震相标注和Ｌｇ波走时表等问题进行了讨论。
On the basis of recordings of local earthquake in Taiwan and Ryukyu area by seismic stations of Zhejiang and Fujian provinces, we studied the compositions and the characteristics of Lg-wave. The results were as follows:the Lg-wave in the area consists of a group of waves with different velocity; Lg1-wave and Lg2-wave could be divided into four phases of Lg′1,Lg″1,Lg′2and Lg″2;the recording characteristics of seismic phase in different area were obvious different, which indicated the transformation of the crustal structure from continental type to marine one. This paper also discussed the unknown seismic phase, the other factors affecting the recording characteristics of seismic phase, and the sign and travel time-table of Lg-wave.
On the basis of recordings of local earthquake in Taiwan and Ryukyu area by seismic stations of Zhejiang and Fujian provinces, we studied the compositions and the characteristics of Lg-wave. The results were as follows:the Lg-wave in the area consists of a group of waves with different velocity; Lg1-wave and Lg2-wave could be divided into four phases of Lg′1,Lg″1,Lg′2and Lg″2;the recording characteristics of seismic phase in different area were obvious different, which indicated the transformation of the crustal structure from continental type to marine one. This paper also discussed the unknown seismic phase, the other factors affecting the recording characteristics of seismic phase, and the sign and travel time-table of Lg-wave.
引文
1PreesF．andEwingM，TwoslowsurfacewavesacrossNorthAmerice．BSSA，1952，43．2BathM，TheelasticwavesLgandRgalongEuroasiaticpaths，ArkivfurGeophsik．1954，2．3国家地震局地球物理研究所．震相便查表．北京：地震出版社，1980．4赵荣国．Lg、Qm、Rmz震相走时表．地震地磁观测与研究，1988，9（1）．
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