地质学报2025，Vol.99Issue(7)：2251-2270,20.DOI:10.19762/j.cnki.dizhixuebao.2024252
鄂尔多斯盆地陇东地区下二叠统太原组和山西组的物源区转变:中央古隆起消失的响应
Provenance transformation of Lower Permian Taiyuan Formation and Shanxi Formation in Longdong area of Ordos basin:Response to disappearance of Central paleo-uplift
摘要
Abstract
The characteristics of a provenance area and its transformation can reflect the paleogeographic evolution and dynamic change of a basin.Based on petrological,mineralogical,and detrital zircon U-Pb-Hf isotope analyses,this study reveals the provenance areas and their vertical and spatial variations in the Lower Permian Taiyuan and Shanxi formations in the southeastern part of the Central paleo-uplift of the Ordos basin.These findings provide new evidence for reconstructing the Late Paleozoic paleogeographic evolution and dynamics of the Central paleo-uplift.The results indicate that the provenance of the aluminiferous rock series in the Taiyuan Formation was mainly derived from the North Qinling-North Qilian orogenic belt to the south and avanished provenance in the eastern North China craton.However,the contributions of these two provenance areas exhibit significant vertical and horizontal differences.From the lower part to the upper part and from south to north,the contribution from the North Qinling-North Qilian orogenic belt decreases,whereas the contribution from the vanished provenance area in the eastern North China craton increases rapidly.The quartz sandstone at the bottom of the Shanxi Formation shows a provenance shift toward the northern Yinshan block and its southern Khondalite belt.This provenance transformation during the Early Permian indicates that the sedimentary period of the Taiyuan Formation in the Longdong area inherited the earlier paleogeographic framework,which opened to the east,with a low-relief north and higher south.However,the southern uplift has gradually decreased,which is related to the weakening activity in the North Qinling-North Qilian orogenic belt along the southern margin of the Ordos basin.In the early sedimentary period of the Shanxi Formation,the paleogeographic features underwent a fundamental change:the Central paleo-uplift gradually disappeared,transformed into a southward-dipping paleoslope.This changeis related to the final closure of the Paleo-Asian Ocean and the intense uplift of the Inner Mongolia paleo-uplift.关键词
晚古生代/物源区/中央古隆起/陇东地区/鄂尔多斯盆地Key words
Late Paleozoic/provenance area/Central paleo-uplift/Longdong area/Ordos basin引用本文复制引用
朱森,曹高社,石小虎,姚泾利,孙凤余,周昕航,牛永斌..鄂尔多斯盆地陇东地区下二叠统太原组和山西组的物源区转变:中央古隆起消失的响应[J].地质学报,2025,99(7):2251-2270,20.基金项目
本文为国家自然科学基金项目(编号41472104)、河南省自然科学基金项目(编号232300420168)、河南省高等学校重点科研项目(编号23A170004)和中国石油长庆油田分公司项目(编号2022-37)联合资助的成果. （编号41472104）
