新疆其木干剖面新近纪沉积序列与西昆仑隆升的耦合  

Neogene Uplift of West Kunlun Coupled to the Sedimentary Succession from Qimugan Section,Xinjiang,NW China

作　　者：陈锐明[1] 张克信[2] 陈奋宁[1] 徐亚东[2,3] 叶荷[4] 陈林[2,3] 

机构地区：[1]西安地质矿产研究所,西安710054 [2]中国地质大学生物地质与环境地质国家重点实验室,武汉430074 [3]中国地质大学研究生院,武汉430074 [4]广东省地质勘查局七六五地质大队,广东惠州516000

出　　处：《地质科技情报》2011年第4期55-64,共10页Geological Science and Technology Information

基　　金：中国地质调查局项目(1212011121261);国家自然科学基金项目(4092106240830212)

摘　　要：位于西昆仑山前塔西南地区的其木干剖面发育连续完整的新近纪地层，总厚1831．3m。从古近系一新近系的微角度不整合接触界面向上依次出现中新统乌恰群的克孜洛依组、安居安组和帕卡布拉克组，上新统的阿图什组和西域组底部。其木干剖面克孜洛依组至阿图什组整体为1个二级层序，可划分为9个-2级层序。通过细致分析沉积相与层序发育特征，揭示出这套新近纪沉积序列与西昆仑的隆升具有良好的耦合关系：（1）Sql层序底界面代表着西昆仑乃至整个高原第一次整体隆升，即喜马拉雅运动A幕。（3）Sql至Sq3沉积时期，盆地挠曲沉降，构造活动强烈，对应喜马拉雅运动B幕。层序发育模式表现为退积型副层序组与进积型副层序组相当。（3）Sq4至Sq5下部沉积时期，盆地进一步挠曲沉降，西昆仑表现出10～8Ma的强抬升剥露期，对应喜马拉雅运动C幕。层序发育模式以进积型副层序组为主，退积型副层序组较薄。④Sq5上部至Sq8沉积时期，构造活动相对平静。退积型副层序组、加积型副层序组和进积型副层序组均较为发育。⑤Sq9沉积时期，盆地开始萎缩，山体再次隆升。层序发育特征表现为进积型副层序组较退积型副层序组发育，高位体系域含多个进积型副层序组。（6）sq9顶界面代表着青藏高原约3．6Ma的一次整体强烈隆升，即青藏运动A幕。The Qimugan Section, lying in the southwqst Tarim Basin at the northern foot of the West Kunlun Mountains, comprises 1 831.3 m of conformable Miocene to Pliocene strata. Upwards the unconformable boundary between Paleogene and Neogene, there are Miocene Wuqia Group that consists of Keziluoyi Formation, Anjuan Formation and Pakabulake Formation, Pliocene Artux Formation and bottom of Xiyu Formation. The section from Keziluoyi Formation to Artux Formation is composed of a second-order sequence that can be subdivided into nine third-order sequences. The analysis of the sedimentary facies and characteristics of the sequence opens a good coupling relationship between this Neogene sedimentary succession and the uplift of West Kunlun. （1） The bottom boundary of Sql indicates the first uplift of West Kunlun besides all of the Qinghai-Tibet Plateau, namely the phase A of Himalayan movement. （2） In the sedimentary epoch from Sql to Sq3 corresponding to .the phase B of Himalayan movement, tectonic activity was intense and the flexural process of basin began. The modality of sequence showed that the transgressive style and the retrogressive style parasequence sets were equivalent. （3） In the sedimentary epoch from Sq4 to early Sq5 corresponding to the phase C of Himalayan movement, West Kunlun behaved the time of intense uplift and exposed between 10 and 8 Ma, and the flexural process of basin got on. The style of parasequence sets is dominated by transgression with weak retrogression. （4） In the sedimentary epoch from terminal Sq5 to Sq8, tectonic activity was relatively calm. Thus the parasequenee sets of transgressive style, retrogressive style and accretion style were all developed. （5） In the sedimentary epoch of Sq9, another uplift of the mountains commenced and the basin began to shrink. The modality of sequence showed that the transgressive style parasequence sets developed better than the retrogressive style, and highstand systems tract just contained four transgressive style parasequence sets. �

关 键 词：新近纪 层序地层 其木干剖面 西昆仑 隆升 

分 类 号：P534.62[天文地球—古生物学与地层学] P539.2[天文地球—地质学]