Production Data Analysis For Hydraulically Fractured Wells In Tight Formation

One of the biggest challenges in analyzing production data of low permeability reservoirs is that their flow transient regimes is influenced by wellbore storage causing it to stay for a very long period of time.Thus,it is quite challenging to estimate estimated ultimate recovery(EUR)along with reservoir properties such as fracture half length,permeability,drainage area,and fracture conductivity.The lithology of the Jinlong oil field is mainly sand conglomerate making it a tight sand reservoir.This work employs a chosen model and software of hydraulically fractured wells for the application of analyzing the production data from some hydraulically fractured wells in a tight reservoir the results obtained from the software.Production analysis is a robust tool when used with traditional well testing analysis to obtain consistent results.To increase our confidence in the drainage area and EUR predictions in the tight oil reservoirs,we applied an integrated production analysis approach with multiple data types from nine vertical and two horizontal hydraulically fractured wells.There are a number of softwares that could be used to analyze production data.This work also incorporates the derivative of the fractured well solution and the formulae for fractured well type curves,measuring rate and pressure for the various analyses done with software.It should be noted that the data set used in this work is of poor quality.The analysis integrates Decline Curve Analysis(DCA),Type Curve Analysis(such as Blasingame type-curve),Flowing Material Balance(FMB),Pressure Transient Analysis(PTA),Rate Transient Analysis(RTA),and analytical reservoir simulation.After performing this integrated approach on operated wells in the study area located in Xinjiang Province,the wells with the most successful completion methods were identified.We demonstrate that the integrated approach can be progressively improved as more production and flowing pressure data are available over time.The proposed integrated approach provided valuable guidelines for data acquisition and EUR estimation.This knowledge can then apply to future wells in the same area for optimum production enhancements.Well test analysis was conducted on a few of the wells and the results obtained are compared with results from production data analysis obtained from RTA.From the results,it could be seen that there's a slight variation in the two results but on a whole,production data analysis yields/gives better results than well test analysis.