新疆西博格达山周缘地区中新生代沉积岩源区和构造背景

摘要

沉积岩中的碎屑组分及相对稳定的微量元素和稀土元素可以反映物源信息，广泛应用于沉积源区的确定和构造背景的分析。本文通过对西博格达山周缘地区侏罗纪至古近纪沉积地层的碎屑岩岩石学和微量元素与稀土元素分析，揭示盆地沉积岩的源岩来自上地壳，岩性以长英质岩石为主，混合部分安山质及基性岩石。源区构造背景应为岩浆弧和再循环造山带，其中岩浆弧起主导作用。本文的分析结果为研究博格达山的构造演化过程及其机制提供了有力的证据，并且对准噶尔盆地油气勘探具有一定指导意义。%The integration of petrological,trace element and rare earth element analysis for the Jurassic to the Palaeogene sedimentary rocks around the western Bogeda Mountains,Xinjiang shows that the source rocks of the sedimentary rocks should be derived from the upper crust,and consist dominantly of felsic rocks with the mixtures of andesitic and basic rocks. The tectonic settings of the provenance should be represented by the magmatic arcs and recycled orogens. The results of research in this study may provide essential provements for the study of tectonic evolution and attributes of the provenance of the Jurassic to the Palaeogene sedimentary rocks around the western Bogeda Mountains,and thus are of great significance to the oil and gas exploration in the Junggar Basin, Xinjiang.