运用磷灰石裂变径迹分析十万山盆地的地热史  

GEOTHERMAL HISTORY OF SHIWANSHAN BASIN AND ITS NEIGHBOURING REGION USING APATITE FISSION-TRACK ANALYSIS

作　　者：汪新伟[1] 汪新文[1] 韩效忠[1] 

机构地区：[1]中国地质大学地球科学与资源学院,北京100083

出　　处：《石油与天然气地质》2003年第4期385-390,412,共7页Oil & Gas Geology

基　　金：中国石化南方海相油气勘探项目 ( 0 0 -0 10 )资助

摘　　要：通过对十万山盆地及邻区磷灰石裂变径迹样品的表观年龄特征和封闭径迹长度分布特征的分析与正演模拟 ,定性 -半定量地研究了该区相关岩石组合的地热演化史。结果表明 :所有样品均经历了 6 0～ 70℃以上的古地温 ;盆地北西侧的基底地层 (T1b)比盆地南东侧的基底岩系 (γ15)隆升剥蚀到达浅部 (低于 70℃的不退火温度 )的时间要相对早得多 ;盆地内样品的古温度史表明了多期次的构造运动致使区内古地温场经历了 6个阶段 ,即晚三叠世 -晚侏罗世的快速埋藏增温阶段、晚侏罗世末 -早白垩世初的短暂降温阶段、白垩纪的再次埋藏增温阶段、晚白垩世末 -古新世的快速降温阶段、始新世 -渐新世稳定阶段和中新世以来的快速降温阶段 ,区内烃源岩演化历史比较复杂。The geothermal history of strata or rocks has been qualitatively and semi-quantitatively in Shiwanshan basin and its neighbouring region, based on analyses of fission-track apparent age and modelling of confined track lengths distribution of apatite samples.The results show that all samples have experienced paleogeotemperatures of over 60～70℃;the basement strata(T 1b) on the northwestern side of Shiwanshan basin have been uplifted and denuded to the near-surface (with a paleogeotemperature of below 70℃) much more earlier than the basement rocks(γ 51)on the southeastern side of the basin and the paleogeothermal history of samples from the basin can be divided into six stages,they are the fast burial and increasing temperature(T 3-J 3)stage,transient decreasing temperature(latest J 3-early K 1)stage,burial and increasing temperature(K)stage,rapid decreasing temperature(last K 2-E 1)stage,relatively stable (E 2-E 3)stage and another rapid decreasing temperature (since N 1)stage.

关 键 词：油气勘探 十万山盆地 磷灰石 裂变径迹 

分 类 号：P618.13[天文地球—矿床学]