关键词: 沉积盆她, 热演化, 有限单元法, 成油窗口

Abstract: Time-Temperature-Index(TTI)is used in petroleum geology to estimate the location of oil generation window.However,previous method for computation of TTI neglects the thermal effects of compaction of sediments and discharge of porous fluids.It also makes an oversimplification that heat flows in the basin is kept unchanged during the whole sedimentary history and properties of sediments do not vary during their consolidation.In this paper,a new method is proposed to estimate the evolution of both the geotherms and the pore pressure.Geological evidences about the sedimentary history are used to constrain the model parameters and boundary conditions.Experimental results provide the material properties for computation.Finite element technique is applied to solve the coupled nonlinear problem of compaction,discharge,and heat transfer.In comparison with the previous method,this method gives improved results for simple examples,and is able to deal with much more complicated situations.It will not only provide a better estimation of the oil-generation window,but also a better Understanding of the evolution of the sedimentary basin.