盆地地热场模拟的若干问题探讨

本文探讨了盆地地热场模拟所面临的诸多难题的解决途径和方法.作者从地下热流状态平衡与破坏的角度出发,用正常地热场的概念来描述常规上地幔热流对地热场的贡献,而用附加地热场的概念来描述岩浆侵入等事件对地热场的贡献;讨论了采用地壳热结构分析来获取盆地基底热流数值的方法,以及根据重力补偿地区的盆地基底与莫霍面的倒影关系所建立的莫霍面埋深经验公式的有效性;以Ungerer等提供的岩石热导率与岩性、地温之间的关系曲线为基础,采用双重回归方法建立了岩石热导率的经验公式.这些方法在一些盆地的地热场模拟中取得了成效. 

STUDY ON SOME IMPORTANT PROBLEMS OF GEOTHERMAL FIELD SIMULATION OF BASINS

Geothermal field simulation is the basis of basin modeling.This paper probes into some difficult problems about geothermal field simulation of basins and their solving method:(1) From the angle of equilibrum and wreck of underground thermal state,the authors adopt the concepts of normal geothermal field and appended geothermal field to describe the contribution of normal crust mantle convection to the geothermal field and the contribution of magmatic intrusion to geothermal field respectively;(2) The authors try to discuss the method of gaining the thermal flow value about basin bottom,that by using analyzing paleo geothermal structure,and also try to discuss the availability of empirical formula for burial depth of Moho surface which is established on the basis of the relationship of inverted image between basin bottom and Moho surface in gravity compensated area;and (3) Based on the relation curve among thermal conductivity,lithologic characters and earth temperature provided by Ungerer etc,the authors establish an empirical formula about the thermal conductivity of rock through double regression.These methods have been applied to simulation of thermal field of several basins.