地质学报2017，Vol.91Issue(10)：2185-2195,11.
内蒙古银额盆地希热哈达地区中生代构造活动的磷灰石裂变径迹约束
Constraints of Apatite Fission Track on the Mesozoic Tectonic Activities in Xirehada Region, Yin'e Basin, Inner Mongolia
摘要
Abstract
Yin'e Basin,located in western Inner Mongolia,has undergone multiple tectonic alterations since its formation in the Paleozoic.The Yanshan tectonic movement resulted in that the basin experienced the tectonic evolution of intracontinental basin and generated a series of oil sags,such as Chagan depression and Juyanhai depression during the Cretaceous.However,tectonic evolution of the oil sags needs to further address.The study on apatite fission track of the five wells in the Xirehada region,northwestern margin of Yin'e Basin,has revealed the tectonic evolution history of the study area during the Mesozoic.The central fission track ages of 8 samples range from 111±8 Ma to 140±8 Ma and the track lengths range from 12.1±1.9 μm to 12.8±2.2μm.The track lengths in these samples is characterized by single peak and negative bias,reflecting that during the late Jurassic and early Cretaceous,the study area underwent tectonic uplifting and erosion event due to influence of curtain Ⅲ of the Yanshan movement.The study area was dominated by uplifting during this period.Based on the vitrinite reflectance of some drilling samples in study area,the denudation thickness of Middle Lower Jurassic ranges from 1069.06 to 2503.73m,suggesting that the area underwent strong uplifting and oil system was destroyed at this time.The results of thermal history of 8 samples,simulated by Hefty software,also indicate that the study area reached the maximum burial depth before Late Jurassic,followed by a rapid uplift and apatite annealing temperature range,about 120℃,during 140 ～111Ma.Since then,temperature decreased very slowly and continued to maintain the upper limit of annealing temperature,i.e.oil threshold temperature,until 60～40Ma,from then to now there has been no strong tectonic uplifting.Consolidate works of Yagan region,in the middle Yin'e Basin,and Shangdan depression,in the eastern Yin'e Basin(apatite fission track age is 90～113Ma,129～159Ma),it can be recognized that differential uplifting may develop in Yin'e basin during the Mesozoic,besides,influence of tectonic movements on different tectonic sites may vary from period to period,which is favorable to the study of tectonic evolution for Yin'e Basin.Combined with the previous work in the Yagan area and Shangdan depression in the eastern Yin'e basin (especially the age of 90～113Ma and 129～159Ma by apatite fission track),this study confirmed that differential uplifting of the Yin'e basin occurred in the Mesozoic period and different structural positions also show different change due to various tectonic movement,both providing evidence for study of tectonic evolution of the Yin ' e basin.关键词
内蒙古银额盆地/中生代/磷灰石裂变径迹/构造演化/油气生成Key words
Yin'e Basin/Inner Mongolia/Mesozoic/Apatite fission track/Tectonic evolution/Hydrocarbon generation引用本文复制引用
刘溪,韩伟,魏建设,张云鹏..内蒙古银额盆地希热哈达地区中生代构造活动的磷灰石裂变径迹约束[J].地质学报,2017,91(10):2185-2195,11.基金项目
本文为国家自然科学基金(41202104)、(41502200)、(41602162)资助 （41202104）
国家自然科学重点基金(41630312)资助 （41630312）
中国地质调查局国土资源大调查项目(1212010733506)资助的成果. （1212010733506）
