CAJ | 학술논문

直接采集数字地震记录的原始P波、S波记录波形，与利用Haskell矩阵传递方法得到的理论综合地震图进行对比，通过不断调整介质模型，最后得到台站下方的体波速度结构模型，此方法中得到的S波速度结构不同于通过其他波形转换而来的结果，而是同P波一样从原始波形拟合而来，同时获得地震台下方P、S速度介质模型，这为我们讨论地下介质的性质提供了更多的信息。　　数字地震波形资料取自于唐山市遥测地震台网陡河和滦县的短周期地震记录，共选用了震中距范围为30～60°、震源深度为100～600km的5个不同地点的深源远震记录资料。结果表明，台站下方的纵波和横波速度分层结构相当吻合，说明拟合结果相当可靠。两个台站下的地壳厚度均为38km，速度结构在13km的低速层处出现差异，滦县的低速层比陡河要更厚一些。两个台站的地壳速度结构都是高低相同，而且陡河的高低差异较滦县更为显著。唐山震区滦县部分的震源比陡河附近的浅，而1976年唐山7.8级地震发生在陡河附近，可见地震的发生与壳内低速层的差异幅度有关。从泊松比高值来看，地幔顶部存在低速层，该区域是地幔上隆区，可能有部分熔融。
직접채집수자지진기록적원시P파、S파기록파형，여이용Haskell구진전체방법득도적이론종합지진도진행대비，통과불단조정개질모형，최후득도태참하방적체파속도결구모형，차방법중득도적S파속도결구불동우통과기타파형전환이래적결과，이시동P파일양종원시파형의합이래，동시획득지진태하방P、S속도개질모형，저위아문토론지하개질적성질제공료경다적신식。　　수자지진파형자료취자우당산시요측지진태망두하화란현적단주기지진기록，공선용료진중거범위위30～60°、진원심도위100～600km적5개불동지점적심원원진기록자료。결과표명，태참하방적종파화횡파속도분층결구상당문합，설명의합결과상당가고。량개태참하적지각후도균위38km，속도결구재13km적저속층처출현차이，란현적저속층비두하요경후일사。량개태참적지각속도결구도시고저상동，이차두하적고저차이교란현경위현저。당산진구란현부분적진원비두하부근적천，이1976년당산7.8급지진발생재두하부근，가견지진적발생여각내저속층적차이폭도유관。종박송비고치래간，지만정부존재저속층，해구역시지만상륭구，가능유부분용융。
The original P and S wave pattern collected directly from digital earthquake record is compared with theoretical seismograms got from Haskell matrix transmitting.Through adjusting model,the body wave velocity structure model for the medium beneath the stations is obtained.THe S wave velocity structure in this method,which is different from the results that transformed from other wave,is obtained from simulating the original S wave like we did with the P wave.Meanwhile we also got the　P and S velocity medium model.It will provide more information when we discuss the characters of the medium. 　　The digital earthquake records were collected from Tangshan telemetry network.We selected five short-period earthquake records of Douhe and Luanxian station,which the range of epicentral distance is 30°～60°,focal depth range is 100～600km.The results show that the layered structure of longitudinal wave coincides well with the transversal wave.It proves the results are reliable.The thickness of earth crust under both the two stations is 38km.The difference appears in the low velocity layer under 13km deep,where the low velocity layer of Luanxian is thicker than Douhe.The high and low velocity layer under the two stations appears alternately,and the difference from high to low in Douhe is more distinct than in Luanxian.The focus of Luanxian in Tangshan seismic area is shallower,but the main earthquake of Tangshan in 1976 took place in Doune area,so it is clear that the occurrence of earthquake is related to the amplitude between high and low velocity layer.From the view of high Poisson ratio,There are low velocity layers on the top of mantle in the region.The region is a swelling area of mantle and there may be some partial melt.