Different Burial-Cooling History of Triassic Strata between the Western Weibei Uplift and the Northwestern Weihe Basin in Northwest China  

作　　者：Qiang Yu Zhanli Ren Rongxi Li Chung Ling Tao Ni Wanshan Lei Baojiang Wang Xiaoli Wu Xiaoli Qin Xianghe Lei 

机构地区：[1]The School of Earth Science and Resources,Chang'an University,Xi'an 710054,China [2]Research Institute on Wisdom Oil&Gas Field,Chang'an University,Xi'an 710054,China [3]State Key Laboratory of Continental Dynamics,Northwest University,Xi'an 710069,China [4]School of Earth Sciences,The University of Melbourne,Parkville,Victoria 3010,Australia [5]School of Information Technology,Xichang University,Xichang 615000,China

出　　处：《Journal of Earth Science》2023年第5期1543-1555,共13页地球科学学刊（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos.41630312,41602128,41703055);the “Research Grants by China Geological Survey (No.DD20160060)”;the “Fundamental Research Funds for the Central Universities;CHD (Nos.300102279206,300102278204)”;the fund from China Scholarship Council。

摘　　要：Analysis of tectonothermal history of the Yanchang Formation in the western Weibei Uplift and in the northwestern Weihe Basin can reconstruct the cooling history of the southwest most remained Upper Triassic source rock of the North China Plate. Apatite fission-track(AFT) and(U-ThSm)/He(AHe) analysis were used to recover the cooling and uplift history of the Upper Triassic here. Ten sandstones from the Middle–Upper Triassic strata yield AFT ages between 179.8 ± 7.4 and 127.6 ± 8.1 Ma. AHe ages of two sandstones have the value of 37.7 ± 2.3–131.1 ± 8.1 and 45.7 ± 2.8–83.5 ± 5.2 Ma. Time-temperature modeling results showed that tectonothermal history of the Yanchang Formation was initially different in time-space relationships but then became almost identical through time followed by different cooling rate. Modeling results of the Triassic strata in the Qianyang area and the Yaojiagou area revealed three different uplift-cooling stages commencing in the Late Jurassic at ~165 Ma and in Early Cretaceous at ~110 Ma, respectively, both followed by first similar cooling histories to the Early Miocene at ~20 – 23 Ma and then different since the Late Miocene. Uplift-cooling rate since the Late Miocene at ~8 Ma were different between the Western Weibei Uplift and the Northwestern Weihe Basin. The timing, cooling-uplift rates of the Yaojiagou area, which was mainly controlled by movements related to the Liupanshan Mountains, the Qinling Orogens and the Weibei Uplift, had the earliest onset of uplift-cooling for the Upper Triassic series compared to other regions within the Weibei Uplift. Cooling paths for the Upper Triassic series became uniform regionally in the Early Cretaceous marking a key time for the tectonothermal evolutionary history of Upper Triassic series in the southwestern North China Plate.

关 键 词：apatite fission track THERMOCHRONOLOGY (U-Th-Sm)/He Yanchang Formation tectonothermal history UPLIFT cooling geochemistry 

分 类 号：P618.13[天文地球—矿床学] P534.51[天文地球—地质学]