镜质体反射率的热史反演

利用地层剖面中系统测定的镜质体反射率，依据各构造演化阶段热流变化的不均一性，分阶段模拟热流在地史演化中的变化。充分利用了最为流行的成熟度计算模型（ＬｏｐａｔｉｎＷａｐｌｅｓ模型，Ｒｏｙｄｅｎ模型，ＭｉｄｄｌｅｔｏｎＦａｌｒｅｙ模型，ＥＡＳＹ模型）进行古热流反演，其基本原理是调整热流值及模型中待调参数，达到最佳拟合时的热流值即为古热流值。改进了Ｌｅｒｃｈｅ的简单热流变化模型。通过上述模型的计算可以模拟出复杂条件下的热史变化过程。在此模拟方法中还考虑了剥蚀作用以及由于压实作用引起的岩石热导率变化。对鄂尔多斯盆地某区块进行了实际计算，应用效果较好。图２表１参５（梁大新摘）

The inversion of thermal processes from vitrinite reflectance.

As the characteristics of thermal flow in various tectonic evolution episodes are different, the systematic vitrinite reflectances of a stratum profile are used to model and calculate paleothermal flow in every interval. The most popular maturity models (Lopatin Waples, Royden, Middleton Falrey and EASY% model) are used to inverse paleothermal flow, and the simple Lerche model is improved. The thermal flow value and indefinite parameter are adjusted to imitate the vitrinite reflectances, when the thermal flow value is met to the best imitation, it is the paleothermal flow. By these models, thermal process in complex geologic situation can be calculated quantitatively. It is an non linear thermal inversion program, and erosion and variety of rock heat conductivity are also considered in this program. It is used to calculate paleothermal flow in Ordos basin. There is a high heat flow during Permian of Late Paleozoic. Since Triassic the basin belong to compressional flexural depression, heat flow value decreased gradually. But the rate in fall of heat flow at various stages is different. The result of calculation from four models shows that thermal flow from different models is similar, however, every model is not a definite relation. The relation between vitrinite and TTI varies from basin to basin and from one stage to another.