Research On Prediction Method Of Formation Pressure From Array Induction Logs

Formation pressure refers to the rock pore fluid pressure.which is also known as formation pore pressure, In oil and gas exploration, the formation pressure is one of the most important parameters, it is the direct embodiment of subsurface fluid energy, an important driving force of oil and gas migration, and one of the basis of design and construction of drilling parameters.With the continuous development of oil and gas exploration technology, enhance the continuity of logging data, high resolution, economic value is more and more high, prediction of logging in formation pressure application is more and more important. The method in this paper through the investigation and evaluation of formation pressure, combined with logging data collected on a block formation pressure.There are two main traditional methods of formation pressure (equivalent depth method and Eaton method). With the change of depth, setting up the normal compaction trend line in normal compaction period through a variety of parameters, and then predicting the formation pressure by the degree of difference between measured deviating from the trend line.The two methods need to establish a normal compaction trend line. If the mudstone selection is not appropriate, it will make the formation pressure calculation results very different. And the BP neural network only need to establish the network and then evaluate the pressure of this area. This greatly reduces the burden of the personnel, and makes the results more reliable.Based on the conventional logging and array induction logging data, Using damping least square method of array induction logging in article 6 or 5 curve for inversion, by giving a set of initial values of equations of iteration to calculate a set of least-square solutions.the invasion radius is obtained by using the high resolution characteristic of the array induction logging, and the formation pressure is obtained by using the theory of percolation mechanics. Evaluation of conventional logging mainly using density logging curves and acoustic logging method. However, the conventional method is mainly applicable to the mudstone formation, and sandstone formations. In order to solve this problem, this paper uses the array induction logging data inversion method to predict the formation pressure, so as to solve the problem.