川西坳陷鸭子河地区基于多种古温标的钻井热史恢复  

Thermal history reconstruction based on multiple paleo-thermal records of the Yazihe area,western Sichuan depression

作　　者：朱传庆[1,2] 邱楠生[1,2] 江强[1,2] 胡圣标[3] 张硕[1,2] 

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [2]中国石油大学(北京)地球科学学院,北京102249 [3]中国科学院地质与地球物理研究所岩石圈演化国家重点实验室,北京100029

出　　处：《地球物理学报》2015年第10期3660-3670,共11页Chinese Journal of Geophysics

基　　金：国家自然科学基金(41102152);国家重点基础发展研究计划(2012CB214703);中国石油科技创新基金(2013D-5006-0102);中国石油大学(北京)科研基金(YJRC-2013-02)资助

摘　　要：利用镜质体反射率（Ro）、磷灰石裂变径迹（AFT）和伊利石结晶度（IC指数）等古温标恢复了四川盆地川西坳陷的钻井热史,对比了不同温标最高古地温的恢复结果.研究表明,研究区晚白垩世至今总体表现为冷却及抬升剥蚀的过程,地温梯度由约26℃·km^-1降低至约22℃·km^-1,剥蚀量约1.3～1.9km.约80 Ma以来开始抬升剥蚀,40—2.5 Ma经历了一个热平静期,第四纪存在一定的增温,地温梯度增高约5℃·km^-1.三种古地温恢复结果具有较高的一致性,相对于镜质体反射率（Ro）和磷灰石裂变径迹（AFT）等成熟古温标,伊利石结晶度作为有机质成熟度指标和沉积岩古温标的应用处于定性分析阶段,该指标的热演化模型仍需进一步探索.Thermal history is significative to the geodynamics and petroleum geology of a sedimentary basin,for temperature is important for many geodynamic and the hydrocarbon accumulation process,especially the maturation evolution of hydrocarbon source rocks and the history of hydrocarbon generation.In the western Sichuan Basin,a continental depression is superimposed on the Paleozoic craton.The Paleozoic source rocks in this area have experienced a multi-stage and complex structural-thermal evolution and thus require different methods and effective geothermal indicators to reconstruct the thermal history,which will help discover the equivalence between different geothermal indicators and establish a set of geothermal indicators for the thermal history reconstruction of the area.The thermal history of a basin is usually reconstructed using various paleo-temperature indicators,including vitrinite reflectance（Ro）,apatite fission track（AFT）,（U-Th）/He in apatite andzircon,reflectance of bitumen and vitrinite-like macerals,the hydrogen index,and fluid inclusions.Roand AFT are the most widely used indicators and the related modeling methods are relatively well established,other indicators such asillitecry stallinity（IC）,Raman spectroscopy,and acoustic rock emissions have also been studied and used in the quantitative reconstruction of paleo-temperatures.In this paper,the thermal history of the western Sichuan depression was reconstructed based on three geothermal indicators：Ro,AFT and the IC index,using the paleotemperature gradient method, Monte Carlo modeling and the estimation of metamorphic temperature stage respectively,and the maximum paleo-temperatures reconstructed based on different indicators were compared.The thermal history reconstruction of CY92 using the paleo-temperature gradient method shows that the maximum paleo-temperature gradient of this borehole was ～26 ℃·km^-1,the maximum paleo-heat flow was～60mW·m-2,both was larger than the present.The thickness of removed sediments on the surf

关 键 词：镜质体反射率 磷灰石裂变径迹 伊利石结晶度 热史恢复 川西坳陷 

分 类 号：P314[天文地球—固体地球物理学]