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Title:: Mesozoic-Cenozoic Uplift-exhumation History in Luliangshan Area of Shanxi: Evidences from Apatite Fission Track

Author(s):: REN Xing-min; ZHU Wen-bin; ZHU Xiao-qing; WANG Xi; LUO Meng; 1. School of Earth Sciences and Engineering, Nanjing University, Nanjing 210046, Jiangsu, China; 2. Qingdao Institute of Marine Geology, China Geological Survey, Qingdao 266071, Shandong, China; 3. School of Wentian, Hohai University, Ma’anshan 243031, Anhui, China

Keywords:: low temperature thermochronology; uplift-exhumation; fission track; Mesozoic-Cenozoic; tectonic-thermal event; basin-mountain coupling; Shanxi

Abstract:: Tectonic-thermal evolution processes of Precambrian complex in Luliangshan area of North China Craton and its peripheral basin were studied by the means of apatite fission track thermochronology in order to further discuss and recognize the evolution and breakup of North China Craton. The results show that the apatite fission track ages in Luliangshan area of Shanxi are 40-138 Ma, recording the cooling events since Early Cretaceous; fission track ages are positively correlated with the altitudes, and the correlation coefficient is 0.789; the confined track lengths of apatite particles (10.62-12.99 μm) are much shorter than the original length (16.3 μm), indicating that the samples suffer a long annealing process. The time-temperature simulation results of apatite fission track show that there are two rapid uplifts in Luliangshan area. For the first rapid uplift, severe cooling uplift of massif happens from Late Jurassic to Early Cretaceous in Luliangshan area, and the event makes the samples into the partial annealing zone, and subsequently keeps in the zone; for the second rapid uplift, the extending orogeny, which happens since Oligocene in Luliangshan area, is basin-mountain coupling with Shanxi graben, and the massif suffers from rapid uplift and denudation. In addition, the effect of rapid uplift extension eastward of Qinghai-Tibet Plateau since the latest Miocene (about 9 Ma) is not significant on the structure in Luliangshan area.