用镜质体反射率R_o 反演古地温的最优化法

The Optimization Method of Inverse Paleogeotemperature from Vitrinite Reflectance Data

本文在假定研究区的热流符合某一函数模型的基础上,借用现今镜质体反射率实测值 R_o并采用最优化法反演古热流和古地温。对于受热过程不复杂而又年轻的地区,可用线性函数模型;在经历过高热的地区,可用指数函数模型。所提出的方法在四川盆地采用指数函数模型进行了应用试验,并以女基井为例作了介绍,效果令人满意。该方法能给出任意时代的热流 Q(t)和地温 T(t,z),同时也可得到不同时期的镜质体反射率 R_o(t,z)。

Suppose the heat flow in the study area conforms with a certain function model,the measured current vitrinite reflectance Ro might be used to inverse paleoheat-fiux and paleo- geotemperature by an opetimization method.The linear function model may be used in young area with simple thermal history and the index function model could be used in high or over heated(matured)area.The method was demonstrated by well Nüji in Sichuan Basin with index function model in the pa- per,the result is successful.The heat flow Q(t)and geotem- perature T(t,z)in any times could be given and also the vitri- nite reflectance R_o(t,z)in different times could be got by this method.