Tight oil reservoir natural fracture identification method and system based on R/S analysis and finite difference method

• Main Authors: DING WENLONG, YIN SHUAI, HAO SHIYAN, XIAO ZIKANG
• Format: Patent
• Language: Chinese; English
• Published: 03.06.2022
• Subjects: CALCULATING; COMPUTING; COUNTING; DATA PROCESSING SYSTEMS OR METHODS, SPECIALLY ADAPTED FORADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL, SUPERVISORYOR FORECASTING PURPOSES; ELECTRIC DIGITAL DATA PROCESSING; PHYSICS; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE,COMMERCIAL, FINANCIAL, MANAGERIAL, SUPERVISORY OR FORECASTINGPURPOSES, NOT OTHERWISE PROVIDED FOR

The invention discloses a tight oil reservoir natural fracture recognition method and system based on R/S analysis and a finite difference method. The system comprises a logging curve fracture sensitivity analysis module, an R/S analysis module, a finite difference method analysis module, a fracture type judgment module and a linear density measured data supervision iteration module. According to the method, a discrete data finite difference method is introduced, and the purpose of accurately judging the concave section of the R/S curve is achieved by solving the second derivative of the R/S curve; judging whether the GR curve passes R/S independent analysis or not to achieve the purpose of distinguishing the bedding seam and the high-angle seam; and approaching the identified natural fracture linear density data to actually measured data through self-adaptive iterative loop. According to the method, development positions of different types of natural fractures can be accurately indicated, fracture linear den