江西景德镇地区中生代推覆构造变形特征与年代学约束

摘要

景德镇地区位于江西省东北部,扬子板块东部,区内经历了长期的构造演化.通过对区域构造剖面的研究,认为研究区中生代推覆构造的主要形式为由北西向南东的推覆,新元古代双桥山群地层上覆于石炭—三叠纪地层之上,总体构成叠瓦扇或双重构造.最大主压应力(σ1)主要为北西—南东向.在推覆构造系统中,发育于推覆构造断层内的未变形花岗岩锆石U-Pb年龄显示此次构造活动的时间为157 ～ 172 Ma,为燕山早期.受中生代推覆构造作用控制,研究区内与推覆构造同期或者稍晚的岩浆作用沿推覆构造界面侵位并在适当的位置成矿,推覆构造制约着与成矿有关的岩浆运移通道与就位空间.%Jingdezhen area is located in the northeastern Jiangxi province,which belongs to the Yangzi plate,and has undergone long-term tectonic activities.According to the study of regional tectonic section,the Mesozoic thrust-nappe structure direction of the study area is from NW to SE,the upper Shuangqiaoshan group has been pushed to the top of Carboniferous-Triassic strata,and the structural styles of the thrust belt are characterized by imbricate fans and duplexes and the maximum principal compressive stress is SE-NW trend.The study of undeformed granite zircon U-Pb isotope dating shows that the U-Pb isotope age is 157 ～ 172 Ma,and the time of tectonic movement is during early Yanshanian period.The Mesozoic thrust-nappe structure produced the magmatic mineralization process in the Jingdezhen area,and the granites of Jingdezhen area may have invaded from intracontinental subductionrelated transformation tectonic setting during the early Yanshanian.The nappe structure constrains the magmatic evolution and in space associated with mineralization.Then it controls the mineralization process of the deposit.