地质通报2017，Vol.36Issue(2)：258-269,12.
东昆仑花石峡北部上二叠统格曲组砂岩碎屑锆石LA-ICP-MSU-Pb年龄及其构造意义
LA-ICP-MS U-Pb dating of detrital zircons from the Up-per Permian Gequ Formation on the southern margin of the East Kunlun Mountains and its tectonics implications
摘要
Abstract
The Upper Permian (Lopingian) Gequ Formation on the southern margin of the East Kunlun Mountains is composed of conglomerates, sandstones and calcareous mudstones of fan delta-sea carbonate plateau. It is of important significance for the analyz-ing of regional tectonic evolution. This paper reports the detrital zircon ages for sandstone from the Gequ Formation in the area north of Huashixia. The sandstone sample has ages of 412~2448Ma, which can be mainly divided into four age ranges, i.e., 1869~1602Ma, 1396~1270Ma, 1197~877Ma and 572~412Ma. The age ranges indicate that the source regions of the Gequ Formation ex-perienced complex multi-phase geological events, which included the Early Paleoproterozoic tectono-magmatic event, Late Paleo-proterozoic assembly event, Mesoproterozoic rifting event, Late Mesoproterozoic-Early Neoproterozoic tectono-magmatic event and Late Neoproterozoic-Early Paleozoic rifting-extension-assembly event. Magmatic rocks formed during Late Neoproterozoic-Early Paleozoic constituted the main provenance of the Gequ Formation. According to the detrital zircons ages, basin of the Gequ Formation was a"cold basin"similar to foreland basin. Contrast to the Upper Permian, there were many >2000Ma ages in the Lower-Middle Permian, and the dated zircons yielded Hercynian-Indosinian ages, which was first found in the Lower Triassic. The two significant changes were the sedimentary response to the unconformities between Upper Permian and Lower-Middle Permian, Lower Triassic and Upper Permian and the tectonic events represented by them, exhibiting a good tectono-depositional coupling relationship.关键词
上二叠统/格曲组/东昆仑/碎屑锆石LA-ICP-MSU-Pb测年/构造演化Key words
Upper Permian/Gequ Formation/East Kunlun Mountains/detrital zircons LA-ICP-MS U-Pb dating/tectonic evolution分类
天文与地球科学引用本文复制引用
黄晓宏,张海军,王训练,王勋,王振义,戚宜建..东昆仑花石峡北部上二叠统格曲组砂岩碎屑锆石LA-ICP-MSU-Pb年龄及其构造意义[J].地质通报,2017,36(2):258-269,12.基金项目
中国地质调查局项目《东昆仑成矿带地质矿产调查评价成果集成》(编号:12120113028800)、《秦-祁-昆重要结合带组成、成因及演化研究》(编号:1212011121258)和中央高校基本科研业务费专项资金(编号:2652014005) （编号:12120113028800）
