龙门山后山断裂中段汶川-茂县断裂的晚第四纪活动性分析

doi:10.3969/j.issn.0253-4967.2017.03.010

摘要/Abstract

摘要： 龙门山断裂带位于青藏高原东缘与四川盆地交界处，构造位置非常重要，对中国西南地区地形地貌、地质构造以及地震的发生等影响深远。通过卫星影像解译以及野外调查，初步分析认为岷江在汶川-茂县断裂区段主要发育5级阶地。结合前人研究获得的阶地年龄，文中将T₁-T₅阶地年龄分别限定在3~10ka、约20ka、40~50ka、60ka和80ka。另外，通过对区域内断裂沿线的阶地、冲沟等地质地貌的野外调查，结合卫星影像解译和差分GPS测量等工作，认为汶川-茂县断裂在T₃阶地（40~50ka BP）形成后、T₂阶地（约20ka BP）形成前有过活动，而在T₂阶地形成以来不再活动。结合中央断裂、前山断裂均为全新世活动断裂的认识，推测龙门山断裂带的活动已转移到更靠近盆地的中央断裂和前山断裂上。

关键词: 河流阶地, 断裂活动性, 汶川-茂县断裂, 龙门山断裂带

Abstract: The Longmenshan fault zone is located in eastern margin of Tibetan plateau and bounded on the east by Sichuan Basin, and tectonically the location is very important. It has a deep impact on the topography, geomorphology, geological structure and seismicity of southwestern China. It is primarily composed of multiple parallel thrust faults, namely, from northwest to southeast, the back-range, the central, the front-range and the piedmont hidden faults, respectively. The M_S8.0 Wenchuan earthquake of 12^th May 2008 ruptured the central and the front-range faults. But the earthquake didn't rupture the back-range fault. This shows that these two faults are both active in Holocene. But until now, we don't know exactly the activity of the back-range fault. The back-range fault consists of the Pingwu-Qingchuan Fault, the Wenchuan-Maoxian Fault and the Gengda-Longdong Fault. Through satellite image(Google Earth)interpretation, combining with field investigation, we preliminarily found out that five steps of alluvial platforms or terraces have been developed in Minjiang region along the Wenchuan-Maoxian Fault. T₁ and T₂ terraces are more continuous than T₃, T₄ and T₅ terraces. Combining with the previous work, we discuss the formation ages of the terraces and conclude, analyze and summarize the existing researches about the terraces of Minjiang River. We constrain the ages of T₁, T₂, T₃, T₄ and T₅ surfaces to 3~10ka BP,~20ka BP, 40~50ka BP, 60ka BP and 80ka BP, respectively. Combining with geomorphologic structural interpretation, measurements of the cross sections of the terraces by differential GPS and detailed site visits including terraces, gullies and other geologic landforms along the fault, we have reason to consider that the Wenchuan-Maoxian Fault was active between the formation age of T₃ and T₂ terrace, but inactive since T₂ terrace formed. Its latest active period should be the middle and late time of late Pleistocene, and there is no activity since the Holocene. Combining with the knowledge that the central and the front-range faults are both Quaternary active faults, the activity of Longmenshan fault zone should have shifted to the central and the front-range faults which are closer to the basin, this indicates that the Longmenshan thrust belt fits the "Piggyback Type" to some extent.

Key words: river terrace, fault activity, Wenchuan-Maoxian fault, Longmenshan fault zone

中图分类号:

P315.2

王旭光, 李传友, 吕丽星, 董金元. 龙门山后山断裂中段汶川-茂县断裂的晚第四纪活动性分析[J]. 地震地质, 2017, 39(3): 572-586.

WANG Xu-guang, LI Chuan-you, LÜ Li-xing, DONG Jin-yuan. ANALYSIS OF THE LATE QUATERNARY ACTIVITY ALONG THE WENCHUAN-MAOXIAN FAULT -MIDDLE OF THE BACK-RANGE FAULT AT THE LONGMENSHAN FAULT ZONE[J]. SEISMOLOGY AND GEOLOGY, 2017, 39(3): 572-586.

参考文献

陈立春, 陈杰, 刘进峰, 等. 2008. 龙门山前山断裂北段晚第四纪活动性研究［J］. 地震地质, 30(3):710-722. doi:10.3969/j.issn.0253-4967.2008.03.010.
CHEN Li-chun, CHEN Jie, LIU Jin-feng, et al. 2008. Investigation of Late Quaternary activity along the northern range-front fault, Longmenshan［J］. Seismology and Geology, 30(3):710-722(in Chinese).
陈立春, 冉勇康, 王虎, 等. 2013. 芦山地震与龙门山断裂带南段活动性［J］. 科学通报, 58(20):1925-1932.
CHEN Li-chun, RAN Yong-kang, WANG Hu, et al. 2013. The Lushan M_S7.0 earthquake and activity of the southern segment of the Longmenshan fault zone［J］. Chinese Science Bulletin, 58(28):3475-3482.
陈社发, 邓起东, 赵小麟, 等. 1994. 龙门山中段推覆构造带及相关构造的演化历史和变形机制(一)［J］. 地震地质, 16(4):404-412.
CHEN She-fa, DENG Qi-dong, ZHAO Xiao-lin, et al. 1994. Deformational characteristics, evolutionary history, and deformation mechanism of the middle Longmenshan thrust-nappes and related tectonics(Ⅰ)［J］. Seismology and Geology, 16(4):404-412(in Chinese).
邓起东, 陈社发, 赵小麟. 1994. 龙门山及其邻区的构造和地震活动及动力学［J］. 地震地质, 16(4):389-403.
DENG Qi-dong, CHEN She-fa, ZHAO Xiao-lin. 1994. Tectonics, seismicity and dynamics of Longmenshan Mountains and its adjacent regions［J］. Seismology and Geology, 16(4):389-403(in Chinese).
江娃利, 张景发, 谢新生, 等. 2009. 建立在雷达卫星影像判读基础上四川龙门山断裂带晚第四纪活动特征研究［J］. 第四纪研究, 29(3):426-438.
JIANG Wa-li, ZHANG Jing-fa, XIE Xin-sheng, et al. 2009. Late Quaternary activity characteristics of Longmenshan fault zone in Sichuan based on SAR satellite image interpretation［J］. Quaternary Sciences, 29(3):426-438(in Chinese).
李传友, 宋方敏, 冉勇康. 2004. 龙门山断裂带北段晚第四纪活动性讨论［J］. 地震地质, 26(2):248-258. doi:10.3969/j.issn.0253-4967.2004.02.007.
LI Chuan-you, SONG Fang-min, RAN Yong-kang. 2004. Late Quaternary activity and age constraint of the northern Longmenshan fault zone［J］. Seismology and Geology, 26(2):248-258(in Chinese).
李勇, 曹叔尤, 周荣军, 等. 2005. 晚新生代岷江下蚀速率及其对青藏高原东缘山脉隆升机制和形成时限的定量约束［J］. 地质学报, 79(1):28-37.
LI Yong, CAO Shu-you, ZHOU Rong-jun, et al. 2005. Late Cenozoic Minjiang incision rate and its constraint on the uplift of the eastern margin of the Tibetan plateau［J］. Acta Geologica Sinica, 79(1):28-37(in Chinese).
刘树根, 赵锡奎, 罗志立, 等. 2001. 龙门山造山带-川西前陆盆地系统构造事件研究［J］. 成都理工学院学报, 28(3):221-230.
LIU Shu-gen, ZHAO Xi-kui, LUO Zhi-li, et al. 2001. Study on the tectonic events in the system of the Longmen Mountain-West Sichuan foreland basin, China［J］. Journal of Chengdu University of Technology, 28(3):221-230(in Chinese).
马保起, 苏刚, 侯治华, 等. 2005. 利用岷江阶地的变形估算龙门山断裂带中段晚第四纪滑动速率［J］. 地震地质, 27(2):234-242. doi:10.3969/j.issn.0253-4967.2005.02.006.
MA Bao-qi, SU Gang, HOU Zhi-hua, et al. 2005. Late Quaternary slip rate in the central part of the Longmenshan fault zone from terrace deformation along the Minjiang River［J］. Seismology and Geology, 27(2):234-242(in Chinese).
钱洪, 唐荣昌. 1997. 成都平原的形成与演化［J］. 四川地震, (3):1-7.
QIAN Hong, TANG Rong-chang. 1997. On the formation and evolution of the Chengdu plain［J］. Earthquake Research in Sichuan, (3):1-7(in Chinese).
谭锡斌. 2012. 龙门山推覆构造带新生代热演化历史研究及其对青藏高原东缘隆升机制的约束. 北京:中国地震局地质研究所. 8-20.
TAN Xi-bin. 2012. Cenozoic thermal history of the Longmenshan thrust belt:Implication for the uplift mechanism in the eastern margin of the Tibetan plateau. Institute of Geology, China Earthquake Administration, Beijing. 8-20(in Chinese).
唐荣昌, 文德华, 黄祖智, 等. 1991. 松潘-龙门山地区主要活动断裂带第四纪活动特征［J］. 中国地震, 7(3):64-71.
TANG Rong-chang, WEN De-hua, HUANG Zu-zhi, et al. 1991. The Quaternary activity characteristics of several major active faults in the Songpan-Longmenshan region［J］. Earthquake Research in China, 7(3):64-71(in Chinese).
王二七, 孟庆任. 2008. 对龙门山中生代和新生代构造演化的讨论［J］. 中国科学(D辑), 38(10):1221-1233.
WANG Er-qi, MENG Qing-ren. 2009. Mesozoic and Cenozoic tectonic evolution of the Longmenshan fault belt［J］. Science in China(Ser D), 52(5):579-592.
徐锡伟, 闻学泽, 叶建青, 等. 2008. 汶川M_S8.0地震地表破裂带及其发震构造［J］. 地震地质, 30(3):597-629. doi:10.3969/j.issn.0253-4967.2008.03.003.
XU Xi-wei, WEN Xue-ze, YE Jian-qing, et al. 2008. The M_S8.0 Wenchuan earthquake surface ruptures and its seismogenic structure［J］. Seismology and Geology, 30(3):597-629(in Chinese).
杨文光. 2005. 岷江上游阶地沉积记录与气候环境变迁研究. 成都:成都理工大学.
YANG Wen-guang. 2005. Research of sedimentary record in terraces and climate vary in the upper reaches of Minjiang River, China. Chengdu University of Technology, Chengdu(in Chinese).
杨晓平, 冯希杰, 戈天勇, 等. 2008. 龙门山断裂带北段第四纪活动的地质地貌证据［J］. 地震地质, 30(3):644-657. doi:10.3969/j.issn.0253-4967.2008.03.005.
YANG Xiao-ping, FENG Xi-jie, GE Tian-yong, et al. 2008. Geological and geomorphic evidence for the Quaternary activity on the northeast segment of Longmenshan fault zone［J］. Seismology and Geology, 30(3):644-657(in Chinese).
张培震, 徐锡伟, 闻学泽, 等. 2008. 2008年汶川8.0级地震发震断裂的滑动速率、复发周期和构造成因［J］. 地球物理学报, 51(4):1066-1073.
ZHANG Pei-zhen, XU Xi-wei, WEN Xue-ze, et al. 2008. Slip rates and recurrence intervals of the Longmen Shan active fault zone, and tectonic implications for the mechanism of the May 12 Wenchuan earthquake, 2008, Sichuan, China［J］. Chinese Journal of Geophysics, 51(4):1066-1073(in Chinese).
赵小麟, 邓起东, 陈社发. 1994. 龙门山逆断裂带中段的构造地貌学研究［J］. 地震地质, 16(4):422-428.
ZHAO Xiao-lin, DENG Qi-dong, CHEN She-fa. 1994. Tectonic geomorphology of the central segment of the Longmenshan thrust belt, western Sichuan, southwestern China［J］. Seismology and Geology, 16(4):422-428(in Chinese).
周荣军, 李勇, Densmore A L, 等. 2006. 青藏高原东缘活动构造［J］. 矿物岩石, 26(2):40-51.
ZHOU Rong-jun, LI Yong, Densmore A L, et al. 2006. Active tectonics of the eastern margin of the Tibet plateau［J］. Journal of Mineralogy and Petrology, 26(2):40-51(in Chinese).
朱俊霖. 2014. 岷江上游地区阶地初步研究. 成都:成都理工大学. 19-52.
ZHU Jun-lin. 2014. A preliminary study on the terraces in the upper reaches of Minjiang River. Chengdu University of Technology, Chengdu:19-52(in Chinese).
Chen L C, Ran Y K, Wang H, et al. 2013. Paleoseismology and kinematic characteristics of the Xiaoyudong rupture, a short but significant strange segment characterized by the May 12, 2008, M_W7.9 earthquake in Sichuan, China［J］. Tectonophysics, 584:91-101.
Densmore A L, Ellis M A, Li Y, et al. 2007. Active tectonics of the Beichuan and Pengguan faults at the eastern margin of the Tibetan plateau［J］. Tectonics, 26(4):TC4005.
Kirby E, Whipple K X, Burchfiel B C, et al. 2000. Neotectonics of the Min Shan, China:Implications for mechanisms driving Quaternary deformation along the eastern margin of the Tibetan plateau［J］. Geological Society of America Bulletin, 112(3):375-393.
Liu C R, Yin G M, Zhang H P, et al. 2013. ESR geochronology of the Minjiang River terraces at Wenchuan, eastern margin of Tibetan plateau, China［J］. Geochronometria, 40(4):360-367.
Ran Y K, Chen W S, Xu X W, et al. 2013. Paleoseismic events and recurrence interval along the Beichuan-Yingxiu Fault of Longmenshan fault zone, Yingxiu, Sichuan, China［J］. Tectonophysics, 584:81-90.
Sun H Y, He H L, Ikeda Y, et al. 2015. Holocene paleoearthquake history on the Qingchuan Fault in the northeastern segment of the Longmenshan thrust zone and its implications［J］. Tectonophysics, 660:92-106.
Xu X W, Yu G H, Chen G H, et al. 2009. Parameters of coseismic reverse-and oblique-slip surface ruptures of the 2008 Wenchuan earthquake, eastern Tibetan plateau［J］. Acta Geologica Sinica, 83(4):673-684.

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