新疆南天山西段中新生代构造变形与盆山耦合机制探讨  

Study on the Mes-Cenozoic Tectonic Deformation and Basin-range Coupling Mechanism in the Western Part of South Tianshan, Xingjiang

作　　者：牛树银[1] 刘晓煌[2] 孙爱群[1] 张建珍[1] 张新勇[2] 李培菊[1] 

机构地区：[1]石家庄经济学院,石家庄市050031 [2]武警黄金第七支队,山东省烟台市264004

出　　处：《地质调查与研究》2013年第4期241-248,共8页Geological Survey and Research

基　　金：中国地质调查项目:新疆哈拉奇地区区域地质矿产调查(1212011120495);新疆1:5万卡克;色帕巴衣幅区域地质矿产调查(121201120661)

摘　　要：南天山西段山峦叠嶂,沟壑深切,褶皱强烈,断裂纵横。构造演化与中生代以来新疆地区的强烈隆升以及其后的塔里木盆地大规模断陷密切相关,受典型的盆山耦合机制控制。从卷入褶皱作用的地层展布和区域构造变形特征分析,新疆地区在原塔里木地块的基础上,由于大规模地幔物质上涌,于中生代晚期发生强烈隆升,并在隆升的北西缘西南天山一带形成北东东向构造岩浆带。新生代以来,由于新疆隆起轴部强烈的热减薄作用,导致隆起中部发生大规模裂陷,并逐渐形成塔里木断陷盆地。与此同时,构造岩浆活动形成的南天山西段造山带与塔里木断陷盆地构成了较大的(地形)位势差,进而引起南天山西段由北西向南东拆离滑脱。第一期形成的区域性褶皱被改造成一系列倒转褶皱,往往表现出北西翼平缓,地层出露齐全,南东翼陡倾或倒转,甚至在某些背斜倒转翼形成较大规模的逆冲推覆构造,同时相伴产生多条北西向走滑断裂,以调节沿走向滑脱拆离幅度的不均匀性。因此,南天山西段,甚至整个新疆地区,中新生代的区域构造演化应从盆山耦合的视角分析其地球动力学过程。这也许是解开西南天山复杂变形历史的钥匙。Ravines deep, strong folding, fracture aspect of the western part in South Tianshan, Tectonic evolution of Mesozoic and the strong uplift in Xinjiang area, and the subsequent large-scale rift-subsidence of the Tarim Ba- sin are closely related, are under the control of a typical basin-range coupling mechanism. Analysis from the stratigraphic distribution of involved in folding and regional tectonic deformation feature, the Xinjiang area on the basis of the original the Tarim block, because of large-scale mantle upwelling, occurred uplifting in the late Mesozoic, and north western margin of western part in South Tianshan area formed strike NEE tectonic magmat- ic belt. Since the Cenozoic, strong thermal thinning effect of axis part in the Xinjiang uplift, leading to uplift oc- curred in the central part of large-scale rift, and gradually formed the Tarim basin. At the same time, tectonics and magmatic activities formed orogenic belt of western part in South Tianshan and the Tarim Basin constitute the larger （topography） potential difference, causing from the North West to South East decoupling of western part in South Tianshan. Regional fold formation for the first phase is transformed into a series of overturned fold, often show north west limb gently, strata are complete, the eastern limb steep or reversed nappe structure, even formed larger scale thrust-nappe structures in some anticline overturned limb, at the same time, produce a plurality of strike NW strike-slip fault, In order to regulate detachment inhomogeneity amplitude along strike. Therefore, western part of South Tianshan, and even the whole Xinjiang area, the regional tectonic evolution of the Mesozo- ic and Cenozoic analyses the geodynamic processes from the basin-mountain coupling. Perhaps this is to unravel key of complex deformation history of Southwest Tianshan mountain

关 键 词：盆山耦合 构造演化 褶皱作用 推覆构造 南天山西段 

分 类 号：P542[天文地球—构造地质学]