地质学报2024，Vol.98Issue(2)：421-432,12.DOI:10.19762/j.cnki.dizhixuebao.2023149
南海北部扩张的地表过程响应:来自海南岛五指山的磷灰石裂变径迹年龄证据
Surface process responses to the expansion of the northern South China Sea:Age evidence of apatite fission tracks from Wuzhi Mountains,Hainan Island
摘要
Abstract
Hainan Island is an important part of the South China Sea block,and its tectonic evolution can largely reflect the tectonic activity characteristics of the entire South China Sea.During the Cenozoic period,under the neotectonic movement of Hainan Island,the differential rise and fall of fault blocks was relatively obvious,forming a tectonic pattern roughly bounded by the Wangwu-Wenjiao fault,with the subsidence area to the north and the fault-uplift area to the south.Research on the uplift process of the faulted uplift area can reveal the history of neotectonic activity in the Hainan Island,but so far,the cause and timing of the uplift of the southern Qiongzhong Mountains are still controversial.In order to clarify the exfoliation and uplift events in the central part of Hainan Island,this paper selected the Wuzhi Mountain with the highest elevation and the largest elevation difference in the southern Qiongzhong area as the study area,and collected 8 sets of rock elevation samples in this area,with an elevation range of 203.55～1153.52 m.A large number of apatite fission track tests and thermal history simulation analysis were carried out on the collected samples.The results show that the Cenozoic in the Wuzhi Mountain area of the Hainan Island mainly experienced two periods of rapid uplift and exfoliation.The first period is from Oligocene to Miocene(32～17 Ma)when the uplift rate was relatively fast.During this period,the Pacific plate subducted and retreated to the Eurasian plate,and the South China Sea experienced the second expansion,making Hainan Island stretched.The activity was intense,causing the Qiongzhongshan area to uplift rapidly until it turned into a slow uplift during the Middle Miocene.The second stage is the stage of rapid denudation and uplift at the end of the Miocene(5 Ma)when the expansion of South China Sea had ended.With the subduction of the Asian plate under the Philippine plate,the entire northern continental margin of South China Sea was in the stage of accelerated thermal subsidence,and the global climate change was accelerated,resulting in extensive uplift and accelerated denudation in Hainan Island.关键词
裂变径迹/新生代构造运动/隆升与剥露历史/海南岛/五指山Key words
fission track/Cenozoic tectonic movement/uplift and denudation history/Hainan Island/Wuzhi Mountains引用本文复制引用
史军华,韩帅,杜建军,韩建恩,孙东霞,胡道功..南海北部扩张的地表过程响应:来自海南岛五指山的磷灰石裂变径迹年龄证据[J].地质学报,2024,98(2):421-432,12.基金项目
本文为中国地质科学院地质力学研究所基本科研业务费项目(编号 所科研 56)资助的成果. （编号 所科研 56）
