天山内部那拉提断裂带全新世活动证据  

EVIDENCE OF HOLOCENE ACTIVITY OF NALATI FAULT ZONE WITHIN THE TIANSHAN

作　　者：王雷 任治坤[1,2] 何仲太[1,2] 计昊旻 刘金瑞 郭龙 李兴奥 WANG Lei;REN Zhi-kun;HE Zhong-tai;JI Hao-min;LIU Jin-rui;GUO Long;LI Xing-ao(State Key Laboratory of Earthquake Dynamics,Institute of Geology,China Earthquake Administration,Beijing 100029,China;Key Laboratory of Seismic and Volcanic Hazards,Institute of Geology,China Earthquake Administration,Beijing 100029,China;Shandong Earthquake Agency,Jinan 250102,China;Earthquake Risk Prevention and Control of Shandong Province,Jinan 250014,China;National Institute of Natural Hazards,Ministry of Emergency Management of China,Beijing 100085,China)

机构地区：[1]中国地震局地质研究所,地震动力学国家重点实验室,北京100029 [2]中国地震局地质研究所,活动构造与火山实验室,北京100029 [3]山东省地震局,济南250102 [4]山东省震灾风险防治中心,济南250014 [5]应急管理部国家自然灾害防治研究院,北京100085

出　　处：《地震地质》2024年第4期821-836,共16页Seismology and Geology

基　　金：国家自然科学基金(U2239202);科技部项目(2021FY100103);山东省地震局科技创新团队培育专项(TD202303);山东省地震局科研项目(YB2406,YB2106,YW2303,YW2304)共同资助

摘　　要：天山山脉横跨欧亚板块,新构造时期强烈隆升。近年来已有研究表明,天山内部的那拉提断裂带东段全新世活动强烈。然而,针对那拉提断裂带其他段落的活动构造研究仍处于空白。文中选取特克斯段作为突破口,通过遥感解译、地质调查、无人机航测、探槽开挖和^(14)C测年,获得以下认识:1)那拉提断裂带特克斯段线性构造地貌特征清晰,可识别出断层崖、断层三角面、断层陡坎、鼓包、闸门脊、垭口、关门山、定向左旋错动的山脊和冲沟等断层地貌标志;2)基于无人机测图和LaDiCaoz半自动位错测量分析程序,获得水平最小位错量为3.4m;3)断裂发育于元古代和古生代地层中,探槽揭露了半山腰处的断塞塘沉积事件,剖面中至少记录了4次古地震事件;4)^(14)C测年结果显示,深约2m处样品的^(14)C测年结果约为(7.06±0.03)ka BP,最新一次形成的崩积楔的^(14)C测年结果约为(1.67±0.03)ka BP;5)利用OxCal年龄校正,在95.4%置信度下确定4次古地震事件的年龄范围:事件E1为2757BC—413AD、事件E2为3581—429BC、事件E3为4702—3932BC、事件E4为5742—5230BC。综上分析认为,全新世以来那拉提断裂带中段仍然活动强烈。The Tianshan orogenic belt,extending across the Euro-Asian plates,is one of the most significant intracontinental orogenic belts globally.Spanning over 2500km,it traverses China,Kazakhstan,Kyrgyzstan,and Uzbekistan from east to west.The belt has been continuously uplifted due to the collision of the India-Eurasia plate during the Cenozoic era.The Tianshan is divided into three segments:North Tianshan,Middle Tianshan,and South Tianshan.The crust in this tectonic region is being shortened in the north-south direction,and a series of NEE-trending or NWW-trending strike-slip faults have developed to accommodate the deformation.The Nalati fault zone serves as the collision suture between the Central Tianshan block and the Tarim block and marks the boundary between Central and South Tianshan.This fault zone trends NEE and extends southwest into Kyrgyzstan,connecting to the Nikolayev line.Its eastern segment is located north of the Dayouludusi basin.The north-south shortening rate is approximately 2.0mm/a,and the horizontal strike-slip rate is about 2.9mm/a.Reports indicate a north-south shortening rate of 0.8-1.1mm/a since the late Quaternary,suggesting it is a significant Holocene active fault zone.However,research on this fault zone’s activity is limited,with most studies focused on its eastern segment.Research on other sections remains scarce.This study focuses on the middle segment of the Nalati fault zone in Tekes county,Ili Prefecture.The Tekes section trends ENE,starting from Qiongkushitai village in the east,passing through Kalatuori,Ayakeaqia,and Kalawenkeer,and reaching Burili in the west,spanning approximately 55km.Methods employed include remote sensing image interpretation,field geological investigation,UAV aerial surveys,trench excavation,Radiocarbon-14 dating,and semi-automatic horizontal dislocation measurement.The main findings are as follows:1)The linear geomorphological features of the Tekes segment are prominent,with typical fault geomorphological signs such as fault cliffs,triangles,scarps,bulges

关 键 词：天山 那拉提断裂带 特克斯 全新世活动 

分 类 号：P315.2[天文地球—地震学]