本文選題：海原斷裂帶 + 干鹽池拉分盆地�。� 參考：《地震地質(zhì)》2016年04期

【摘要】：沿大型走滑斷裂帶經(jīng)常發(fā)生導(dǎo)致多個(gè)斷層段同時(shí)破裂的級(jí)聯(lián)破裂地震事件。海原斷裂帶在1920年海原M 8駘驁地震時(shí)3個(gè)段同時(shí)發(fā)生破裂,干鹽池拉分盆地即為其西段和中段的分段邊界。沿該盆地內(nèi)新生斷層的古地震研究揭示了晚更新世末期以來(lái)的至少7次古地震事件證據(jù),最新1次事件為1920年海原地震,1920年海原地震之前的1次事件可能與1092年歷史地震對(duì)應(yīng)。對(duì)比分析表明,這些事件可能均為超過(guò)8級(jí)的大地震,其復(fù)發(fā)呈現(xiàn)地震叢集與單個(gè)事件相間排列的規(guī)律,當(dāng)前可能處于最近的1個(gè)地震叢集期內(nèi)。該古地震序列與整個(gè)海原斷裂帶的大地震活動(dòng)歷史的對(duì)比表明,干鹽池拉分盆地內(nèi)新生斷層在級(jí)聯(lián)破裂地震事件發(fā)生時(shí)并非總是同時(shí)破裂,該斷層是否參與破裂可能與該次級(jí)聯(lián)破裂事件的震級(jí)大小有關(guān)。討論整個(gè)走滑斷裂帶大地震活動(dòng)歷史時(shí)應(yīng)避免僅依據(jù)具有一定規(guī)模的拉分盆地內(nèi)部斷層的破裂記錄。
[Abstract]:Cascaded faults along large strike-slip fault zones often cause simultaneous rupture of multiple fault segments. During the 1920 Haiyuan M 8 Tai ao earthquake, three segments of Haiyuan fault zone were ruptured at the same time. The dry Yanchi pull-apart basin is the segmental boundary of the western and middle segments of the fault zone. Paleoseismological studies along the new faults in the basin reveal evidence of at least 7 paleoearthquakes since the end of the late Pleistocene, the most recent event being the 1920 Haiyuan earthquake, and one event before the 1920 Haiyuan earthquake may correspond to the 1092 historical earthquake. The comparative analysis shows that these events may all be large earthquakes with M 鈮，

本文編號(hào)：1824054