The earthquake and its aftershocks from May 2 through September 30, 1983
The earthquake and its aftershocks from May 2 through September 30, 1983
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1983年5月2日至9月30日的地震及其余震
DOI：
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
J. Eaton
中科院分区：
文献类型：
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作者：
J. Eaton
根据艾伦/埃利斯实时处理器（RTP）自动P相起始时间和持续时间测量，对科林加地震序列进行分析，确定了1983年5月2日至9月30日期间6,000多起地震的震源和震级。140多个较大余震的震源机制和当地震级是根据临时科林加地震台网和永久性遥测加州中部地震台网（Calnet）的磁带回放所获得的更详细的观测结果计算出来的。主地震后3小时内的M {ge} 3级地震和1天内的M {ge} 1.7级地震的综合星表似乎基本上是完整的。主震初动图提供了主震断层的两种选择：一条走向北东的逆冲断层; 53{degree}W.倾向西南23度（优选断层面），或走向北的高角度逆断层。53{degree}W.并倾斜东北67度。较大余震的震源机制也表明主要是逆冲断层或逆断层。余震区的长轴长35公里，宽15至20公里，与科林加东北部海岸山脉-大峡谷边界处的背斜岭-吉贾拉尔山结构的轴重合。一个横向的（西南到东北）更安静的带，很少有事件穿过余震区，在那里西北走向的背斜岭连接更广泛的，东西走向的华金岭就在主震的西北部。较小的余震主要发生在较大余震所勾勒出的断层上方的上盘块体中。«少
Analysis of the Coalinga earthquake sequence, based on the Allen/Ellis real-time-processor (RTP) automatic P-phase-onset times and duration measurements, provides hypocentral and magnitude determinations for more than 6,000 events from May 2 through September 30, 1983. Focal mechanisms and local magnitudes of more than 140 of the larger aftershocks were calculated from more detailed observations obtained from magnetic-tape playbacks from both the temporary Coalinga seismic network and the permanent telemetered central California seismic network (Calnet). The combined catalog appears to be substantially complete for events of M {ge} 3 within about 3 hours, and for events of M {ge} 1.7 within about 1 day, after the main shock. The first-motion plot of the main shock offers two choices for the main-shock fault; a thrust fault striking N. 53{degree}W. and dipping 23{degree}SW. (the preferred fault plane), or a high-angle reverse fault striking N. 53{degree}W. and dipping 67{degree}NE. Focal mechanisms of the larger aftershocks also indicate predominantly thrust or reverse faulting. The long axis of the aftershock zone, which is 35 km long and 15 to 20 km wide, coincides with the axis of the Anticline Ridge-Guijarral Hills structure at the Coast Ranges-Great Valley boundary northeast of Coalinga. A transverse (southwest to northeast)more » quiet band with very few events crosses the aftershock zone where northwest-trending Anticline Ridge joins broader, east-west-trending Joaquin Ridge just northwest of the main shock. The smaller aftershocks occur mostly in the hanging-wall blocks above the faults outlined by the larger aftershocks.« less