Simulation Of Dual Laterolog Response In Divate And Horizontal Wells With 3D Finite Element Method

Lateral logging is one of the most popular methods in resistivity well logging, it is widely used to evaluate the porosity and saturation of oil and gas and its production. And can be used to give the description of reservoir and geological conditions and lithology of oil.For the application of horizontal wells and deviate wells in the well logging process, the author simulations Lateral logging equipment response in deviate and horizontal well according to the mode it works by using three dimension finite element method. By using this method, We can get the equipment response curve and resistivity distribution of stratum, it helps to give the interpretation of logging. The innovation of this paper is adopt the remesh method to build model precisionly and in order to modeling dual laterolog response efficiently and accurately, high order basis function is adopted. The results show it has higher efficiency and precision compared with linear basis function. The architecture of this paper as follows:The research of lateral logging domestic and abroad is given in chapter 1, and so is the finite element method and the main contribution of this paper.In chapter 2, the mode of lateral logging equipment is given is given.In chapter 3, the author discusses the process of numerical analysis of the lateral well logging using finite element method in detail. First of all, base the principle of finite element method, differential equations which the field of logging obeys is given, from which gives functional expression and boundary condition, finally, using frontal method to solve stiffness matrix and get the monitor electrode voltage, so we can get the deep and shallow equipment response. By improving the mesh method, multiple stratum in horizontal well and invaded eccentricity can be exitly modeled. the B-electrode also in consideration, results show that it will impact the deep lateral logging result and current.In chapter 4, the auther improves process of simulation of lateral logging. In order to modeling lateral logging response efficiently and accurately, high order basis function is adopted. it shows the higher efficiency and precision compared with linear basis function. Furthermore, the anther optimized the mesh and the boundary condition to reduce the error caused by them.In chapter 5, many simulation results in common environmental condition are given for research of response of lateral logging. By simulation the different electrode, different results and different electrode constant are given. Many conclusion and bed thinkness correction are given in deviate well with different angle and different condition; In horizontal well, different layer and invation is analysised and response curves are given, invasion correction chart and bed thickness correction chart are alse made.Finally, the summarization and expectation of this paper is given. As one of the result of this research, the program of simulating the response of laterolog using 3D finite element method can give result quickly and exitly, it can be help to judge the interpretation of well logging response. The resistivity distribution of stratum which gotten by simulation is an important parameter in interpretation course. The results of this research have good prospects in logging interpretation.