沉积与特提斯地质2025，Vol.45Issue(1)：48-68,21.DOI:10.19826/j.cnki.1009-3850.2025.02001
西准噶尔沙尔布尔提山地区志留纪普里道利世—早泥盆世盆地充填序列及其沉积大地构造意义
Sedimentary-tectonic significance of the Silurian-Devonian basin filling sequence in the Shaerbuerti Mountain area,western Junggar
摘要
Abstract
The Xiemisitai-Shaerbuerti Mountain region,located in West Junggar,Xinjiang,China,represents an important part of the Central Asian Orogenic Belt(CAOB).From the Silurian Pridoli epoch to early Devonian,a set of basin filling sequence transitioning from marine flysch to shelf carbonate is deposited in this region.The spatial-temporal distribution of the sedimentary system and analyses of lithofacies and sources can provide evidence for reconstructing the paleogeographic configuration of western Junggar and the evolution of the Paleo-Asian Ocean.This study conducted a detailed analysis of lithofacies,sandstone clasts,as well as major and trace elements in the Mangkelu Ⅱ section of the Shaerbuerti Mountain area to explore the sedimentary basin's evolution,tectonic background,and provenance attributes.The Mangkelu Ⅱ section consists of the Wutubulake Formation at the bottom and the Mangeer Formation at the top.The facies successions from bottom to top includes slope-basin background deposits,basin turbidites,hyperpycnal flow fans at the shelf margin,shelf,and shallow sea grain shoal,representing an upward-shallowing basin-fill sequence.The main sediments are sandstone,conglomerate,and bioclastic limestone.The sandstone is mainly composed of feldspar and lithics,with an index of compositional variability(ICV)of 1.37,which is greater than 1,indicating low maturity.The sandstone samples are enriched in large ion lithophile elements(LILEs)and depleted in high field strength elements(HFSEs),with a ratio of light rare earth elements to heavy rare earth elements(LREEs/HREEs)ranging from 2.89 to 7.41,averaging 6.15.The provenance and tectonic discrimination diagrams show a mixed source of intermediate-felsic volcanic rocks and andesites,derived mainly from continental and oceanic island arcs.Volcanic rocks from the Xiemisitai-Shaerbuerti Mountain island arc provided abundant material for the basin fill.The transformation of sedimentary facies from turbidites to hyperpycnites in the continental shelf may represent a temporary termination of basin filling and the end of subduction and collision during this period in the Shaerbuerti Mountains.关键词
西准噶尔/志留纪普里道利世—早泥盆世/复理石/岩相/物源/岛弧Key words
western Junggar/Silurian Pridoli epoch to early Devonian/flysch/lithofacies/provenance/island arc分类
地质学引用本文复制引用
杜伟东,张欣松,尹家一,纵瑞文..西准噶尔沙尔布尔提山地区志留纪普里道利世—早泥盆世盆地充填序列及其沉积大地构造意义[J].沉积与特提斯地质,2025,45(1):48-68,21.基金项目
国家自然科学基金(42002017,42072041) （42002017,42072041）
