Low-temperature thermochronology based on the isotopic chronology analysis is the most important tecton-thermal chronology dating method and is the most important branch and forward field of geochronology study.The research field mainly focuses on fission track dating and (U-Th)/He dating.The advance of low-temperature thermochronology in recent years is introduced firstly.Then,taking Dangyang synclinore and Jingshan region,mid Yangtze area for example,the application of low-temperature thermochronology to tecton-thermal history analysis of superimposed basins is discussed.The analysis results show that the dating indicators of different types of low temperature thermochronology can effectively constraint the tecton-thermal evolution process of a geological body when the paleo-temperature is ＜240℃.This gives a quantitative low temperature thermochronology evidence for studying tecton-thermal history of superimposed basins.%叠合盆地构造-热演化史是当前油气地质研究的重点和难点之一.近年来,低温热年代学测龄技术成为构造-热演化史研究的重要技术,多种测龄手段联用极大地拓宽了其应用范围.江汉平原区具有典型的叠合盆地特征,存在当阳复向斜等中新生代多旋回沉积埋藏区和京山地区等多期持续抬升区.在前一类地区,镜质体反射率记录、磷灰石裂变径迹和锆石裂变径迹等综合反映,该区具有“多段式”热历史,至少发生过2次地质事件,分别对应于侏罗纪-早白垩世后以及古近纪后的大规模构造抬升-地层剥蚀事件;在第二类地区,磷灰石裂变径迹、磷灰石和锆石(U-Th)/He测龄、裂变径迹和(U-Th)/He热史反演等综合反映,该区志留系在早白垩世以来先后经历了快-慢-较快的抬升冷却过程,分别对应于晚侏罗世末期-早白垩世地层大幅度抬升冷却、早白垩世-古近纪盆地拉张沉降和古近纪中期盆地内隆起抬升剥蚀事件.不同类型低温热年代学测龄指标可以有效反映沉积埋藏区地层沉降-古地温演化历史,再现多期持续剥蚀区地层冷却和构造抬升-剥蚀过程.
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