Study On Post Reservoir Reconstruction Evaluation Technology Of Deng 4 Gas Reservoir In M Block

The M block Deng 4 gas reservoir is located in the gentle fold belt of central Sichuan Basin,which is a typical carbonate gas reservoir.In recent years,due to poor reservoir physical properties and low gas production,gas wells need to be reformed before they can be put into production.Using the pressure drop data of pump stop during acid fracturing construction,a new set of pressure drop evaluation methods,unsteady state and steady state pressure production capacity evaluation methods were established,and the adaptability and reliability of the above methods were demonstrated;With the above method,the single well evaluation was performed on the reservoir reforming effect of the acid fracturing reforming well in the Deng 4 gas Reservoir in M block.The research method and research idea of this paper provide a certain technical guidance for the design of the reconstruction plan of the Deng 4 gas reservoir in the later period.At the same time,it provides a technical reference for the evaluation of the post-fracuture effect of similar carbonate gas reservoirs at home and abroad.The main research contents completed in this paper include the following aspects:The correlation coefficient method was used to comprehensively analyze the main control engineering and geological parameters affecting the gas reservoir reformation,and a multivariable non-linear regression coefficient method was used to establish a mathematical model for predicting the post-fracuture production of the acid fracturing reforming well of the Deng 4 Gas Reservoir in M Block.On the basis of analyzing the shortcomings of the existing G-function pressure drop analysis method,using the basic theory of seepage,a mathematical model of the bottomhole pressure responses of straight well and asymmetric artificial fracture wells in carbonate gas reservoirs was established;various factors were analyzed to the influence of the stop pump pressure drop data;Finally,on the basis of the above mathematical model,an analysis method for the injection pressure drop of the stop pump was proposed.This method was used to evaluate the effect of single well reservoirs in the high and low permeability areas of M blocks,and the effects of different reservoir modification processes on the reservoir reconstruction effects were analyzed.In response to the post-fracuture stop pump data large fluctuations and large errors in wellhead-bottom-hole conversion,the use of high-pass filtering and denoising algorithms eliminates the effects of pump-out pressure drop data fluctuations;the use of wellbore storage effects variable-density processing algorithms improves wellhead-wells Bottom pressure data conversion accuracy.Established the post-fracuture unsteady and steady-state production evaluation model,and analyzed the reasons for the abnormality of the steady-state production test data,and the corresponding abnormal data processing methods were established.The abnormality curve of the production test of X6 well was corrected and obtained the binomial deliverability equation and absolute unimpeded flow.By comprehensively applying various post-fracuture effect evaluation methods,the reservoir reconstruction effect of the acid fracturing construction wells in the Deng 4 gas reservoirs in Block M was evaluated,and the reliability and accuracy of the post-fracuture effect evaluation methods established in this paper were verified.