广西运动在华南板块北缘的构造响应:来自生物地层学方面的证据  

Tectonic Response of the Kwangsian Orogeny in the Northern Margin of the South China Block:Evidences from Biostratigraphy

作　　者：王欣[1,2,3] 高晓峰 查显锋[1] Wang Xin;Gao Xiaofeng;Zha Xianfeng(Centre for Orogenic Belt Geology,Xi’an Center of China Geological Survey,CGS,Xi’an 710054,China;Field Observation Site on Strata Type Section for the Bottom of Wenlock in Ziyang,Shaanxi,Ministry of Natural Resources,Xi’an 710054,China;State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,CAS,Nanjing 210008,China)

机构地区：[1]中国地质调查局西安地质调查中心,造山带地质研究中心,陕西西安710054 [2]自然资源部中志留统底界层型剖面-陕西紫阳野外科学观测基地,陕西西安710054 [3]中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室,江苏南京210008

出　　处：《地球科学》2024年第9期3199-3211,共13页Earth Science

基　　金：中国地质调查局项目(Nos.DD20243411,DD20240029,DD20230553,DD20230005,DD20230215);中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室开放课题基金项目(No.213121);陕西省自然科学基础研究计划面上项目(Nos.2022JM-149,2023-JC-ZD-15,2022JC-DW5-01,2023-JC-YB-268);国家自然科学基金项目(NoS.42242201,40872004,41302006).

摘　　要：广西运动的构造作用范围是否涵盖华南板块北缘尚存在不同认识,并成为了制约相关构造动力学机制研究的瓶颈.此次研究聚焦北大巴山地区,以精确的笔石生物地层序列为标尺,同时综合岩石学特征认为,广西运动在华南板块北缘存在构造‒沉积响应,其构造启动时间为志留系特列奇阶Spirograptus turriculatus笔石带所代表的时限(~435 Ma),与“扬子上升”第一幕的时限基本一致.在华南板块北缘,广西运动在特列奇阶Oktavites spiralis-Cyrtograptus lapworthi笔石带所涵盖的时间范围内第一次到达构造活动峰值(~433 Ma),期间还伴随着大规模的岩浆活动.本研究进一步扩大了广西运动的构造作用范围,同时也为相关的构造发生模式和动力学机制研究提供了更多的思路和参考,即华南与华北碰撞的远程效应可能是广西运动重要的构造驱动力之一.There is still much debate on whether the Kwangsian Orogeny involved in the northern margin of the South China Block,which consequently restricts our understanding of the tectonic dynamics.In this research,the biostratigraphic and petrological evidence from the North Daba Mountains indicates that the tectonic-sedimentary marks the Kwangsian Orogeny in the north margin of the South China Block.Here,the Kwangsian initiated at Spirograptus turriculatus Biozone(Telychian stage,Silurian),consistent with the first episode of the“Yangtze uplift”(~435 Ma),and it reached the peak of the tectonic activity for the first time at Oktavites spiralis⁃Cyrtograptus lapworthi Biozone(Telychian stage,Silurian)accompanied with the~433 Ma intensive magmatism.This study further expands the tectonic scope of the Kwangsian Orogeny to the north margin of the South China Block,providing important new insights into the tectonic model and dynamics.It is suggested that the distant effects of the collision between the North China Block and South China Block may be one of the important tectonic driving force of the Kwangsian Orogeny.

关 键 词：广西运动 华南板块北缘 构造响应 地层学 志留纪 沉积学. 

分 类 号：P52[天文地球—古生物学与地层学]