本文關(guān)鍵詞：2013年12月16日巴東M5.1地震序列及發(fā)震構(gòu)造分析　出處：《地震地質(zhì)》2016年03期 　論文類(lèi)型：期刊論文

  更多相關(guān)文章： 雙差定位 震源深度剖面 震源機(jī)制 構(gòu)造應(yīng)力場(chǎng) ETAS模型

【摘要】：2013年12月16日湖北省巴東縣發(fā)生M5.1地震,該地震是三峽庫(kù)首區(qū)自2003年蓄水以來(lái)震級(jí)最大的1次。雙差地震精定位結(jié)果顯示,巴東地震序列呈NEE向線(xiàn)性展布,主震震源較深,余震震源深度逐漸變淺。垂直余震優(yōu)勢(shì)展布的震源深度剖面均顯示出向SE變深的特征;傾角約50°左右,向深部變緩,揭示可能的發(fā)震斷層走向NEE,傾向SE,傾角約為50°。利用矩張量反演得到了主震的震源機(jī)制解,與地震序列定位分析比較吻合的是NEE向節(jié)面,綜合判斷該節(jié)面可能為發(fā)震斷層,傾向SE,傾角50°左右,性質(zhì)以走滑為主兼逆沖分量。利用P波初動(dòng)方法求解了ML2.0以上余震的震源機(jī)制,并采用FMSI程序反演得到了震源區(qū)的構(gòu)造應(yīng)力場(chǎng),結(jié)果顯示其方向與區(qū)域現(xiàn)代構(gòu)造應(yīng)力場(chǎng)方向一致,說(shuō)明該地震序列受區(qū)域應(yīng)力場(chǎng)的控制。地震序列發(fā)生在175m高水位運(yùn)行期的水位緩慢降落階段,基于ETAS模型對(duì)流體觸發(fā)作用進(jìn)行了定量檢測(cè),顯示庫(kù)水對(duì)地震序列的觸發(fā)作用占17%,余震自激發(fā)占83%。綜合分析認(rèn)為,巴東M5.1地震為庫(kù)水觸發(fā)的構(gòu)造型地震,NEE向斷裂構(gòu)造為可能的發(fā)震構(gòu)造。
[Abstract]:In December 16, 2013, the M5.1 earthquake occurred in Badong County, Hubei Province, which was the 1 largest magnitude since the storage of the Three Gorges Reservoir since 2003. The results of the double difference seismic precision show that the Badong earthquake sequence is NEE linear, the main earthquake source is deeper and the focal depth of the aftershock is gradually shallower. The vertical depth profiles of the vertical aftershocks show the characteristics of SE depth. The dip angle is about 50 degrees, and the depth changes slowly, revealing the possible trend of NEE, SE, and the dip angle is about 50 degrees. The focal mechanism solution of main shock is obtained by using moment tensor inversion. It coincides with the NEE section to locate the earthquake sequence. It is judged that the joint surface may be a seismogenic fault. It tends to SE, and the inclination is about 50 degrees. The main character is strike slip and thrust component. The focal mechanism of aftershocks over ML2.0 has been solved by P wave initial motion method. The tectonic stress field in the focal area has been retrieved by FMSI program. The results show that the direction is consistent with the direction of modern tectonic stress field in the area, indicating that the earthquake sequence is controlled by the regional stress field. The earthquake sequence occurred at the stage of slow fall of 175m high water level operation period. Based on the ETAS model, we quantitatively detected the fluid triggering effect. It showed that the triggering effect of reservoir water on the earthquake sequence accounted for 17%, and the aftershock self excitation accounted for 83%. The comprehensive analysis shows that the Badong M5.1 earthquake is a tectonic earthquake triggered by the reservoir water, and the NEE fault structure is a possible seismogenic structure.
【作者單位】： 中國(guó)地震局地球物理研究所;中國(guó)地震局地震研究所地震與大地測(cè)量重點(diǎn)實(shí)驗(yàn)室;
【基金】：國(guó)家自然科學(xué)基金(41304046) 中國(guó)地震局社會(huì)公益研究項(xiàng)目(1521401800043)共同資助
【分類(lèi)號(hào)】：P315.2
【正文快照】： 2)中國(guó)地震局地震研究所,地震與大地測(cè)量重點(diǎn)實(shí)驗(yàn)室,武漢4300710引言2013年12月16日13時(shí)4分,湖北省恩施土家族自治州巴東縣發(fā)生M5.1地震,此次地震距離三峽水庫(kù)大壩約66km,震中烈度達(dá)Ⅶ度,是三峽水庫(kù)2003年5月蓄水以來(lái)發(fā)生在庫(kù)首區(qū)的最大地震。此次地震共造成5人受傷,約740人失，

本文編號(hào)：1343674