發(fā)布時間：2018-02-26 09:33

  本文關鍵詞： 彈性塊體 GPS 斷層 滑動速率 地震矩虧損　出處：《地球物理學報》2016年05期 　論文類型：期刊論文

【摘要】：本文搜集、整理1998—2013年境內外天山及周邊地區(qū)(包括中國新疆、哈薩克斯坦、吉爾吉斯斯坦等)500余個GPS觀測點數(shù)據,采用GAMIT/GLOBK軟件對其進行解算和平差計算,并利用了彈性塊體模型計算區(qū)域塊體邊界斷層閉鎖深度、塊體運動參數(shù)和主要活動斷層的滑動速率.研究結果表明,東、西昆侖地震帶閉鎖深度最大(19km),其次為南天山地區(qū),閉鎖深度達到17km,閉鎖深度最小的為哈薩克斯坦(13km);各塊體相對歐亞板塊作順(逆)時針旋轉,旋轉速率最大(-0.7208±0.0034°/Ma)為塔里木塊體,其圍繞歐拉極(38.295±0.019°N,95.078±0.077°E)順時針方向轉動,旋轉速率最小為天山東段(0.108±0.1210°/Ma),而天山東、西兩段無論是在旋轉速率上還是在旋轉方向上都有顯著的區(qū)別.西昆侖斷裂帶的滑動速率(10.2±2.8mm·a-1)最大,南天山西段滑動速率為9.5±1.8mm·a-1,其東段為3.9±1.1mm·a-1;而北天山東段滑動速率(4.7±1.1mm·a-1)高于北天山西段(3.7±0.9mm·a-1);塔里木盆地南緣的阿爾金斷裂帶平均滑動速率為7.6±1.4mm·a-1,其結果與阿勒泰斷裂帶滑動速率(7.6±1.6mm·a-1)基本相當;天山斷裂帶運動方式主要以擠壓為主,而阿爾金、昆侖、阿爾泰以及哈薩克斯坦斷裂帶均是以走滑運動方式為主,除阿勒泰斷裂帶走滑方式為右旋以外,其余幾個斷裂帶均為左旋運動.最后,利用主要斷裂帶的滑動速率計算出各地震帶的地震矩變化率以及1900年以來地震矩累計變化量,其結果與利用地震目錄計算所得到的地震矩進行比較,判定出各地震帶上地震矩均衡分布狀態(tài),研究結果顯示阿爾金、西昆侖、東昆侖和北天山東段斷裂帶存在較大的地震矩虧損,均具有發(fā)生7級以上地震的可能性,南天山東段和哈薩克斯坦斷裂帶地震矩虧損相對較小,具有孕育6~7級地震的潛能,而天山西段、阿勒泰地震矩呈現(xiàn)出盈余狀態(tài),不具在1~3年內有發(fā)生強震的可能.
[Abstract]:This paper collects and collates the data of more than 500 GPS observation points in Tianshan Mountains and its surrounding areas (including Xinjiang, Kazakhstan, Kyrgyzstan, etc.) from 1998 to 2013, and calculates the difference between them by using GAMIT/GLOBK software. The elastic block model is used to calculate the block boundary fault locking depth, block motion parameters and the slip rate of the main active faults. The results show that the East and West Kunlun seismic belt has the largest locking depth of 19 kmg, followed by the South Tianshan area. The atresia depth was 17km, and the minimum latchup depth was 13kmm of Kazakstan. Each block rotated clockwise relative to the Eurasian plate. The maximum rotation rate was -0.7208 鹵0.0034 擄/ Ma. it was a Tarim block, and it rotated clockwise around the Euler pole (38.295 鹵0.019 擄N95.078 鹵0.077 擄E). The minimum rotation rate is 0.108 鹵0.1210 擄/ m ~ (-1) in the eastern segment of Tianshan Mountain, but there are significant differences in rotation rate and direction of rotation between the two segments in Tianshan and Shandong. The slip rate of the West Kunlun fault zone is 10.2 鹵2.8 mm 路a ~ (-1). The slip rate of the southern Tianshan Shanxi section is 9.5 鹵1.8 mm 路a -1 and the eastern segment 3.9 鹵1.1 mm 路a -1, while the eastern segment of the North Tianshan Mountain is 4.7 鹵1.1 mm 路a -1) higher than that of the western part of the North Tianshan Mountain, and the average slip rate of the Altun fault zone in the southern margin of the Tarim Basin is 7.6 鹵1.4 mm 路a -1, which is basically equivalent to that of the Aletai fault zone (7.6 鹵1.6 mm 路a -1). The Tianshan fault zone is mainly driven by compression, while the Altun, Kunlun, Altai and Kazakstan fault zones are mainly strike-slip, except for the Altay fault zone, where the strike-slip pattern is dextral. The other fault zones are all left-handed motion. Finally, the seismic moment variation rate of each seismic zone and the accumulative variation of seismic moment since 1900 have been calculated by using the sliding rate of the main fault zone. The results are compared with the seismic moments obtained by using earthquake cataloguing, and the equilibrium distribution of seismic moments on each seismic belt is determined. The results show that Altun and West Kunlun, The fault zone of East Kunlun and North Tianshan has a large seismic moment deficit, both of which have the possibility of occurrence of earthquakes with M 鈮，

本文編號：1537457