The paper discusses a method of defining a relationship between the quantity and frequency of well tests on one hand and pressure map accuracy on the other hand. Dependence of average reservoir pressure deviation between two wells from distance between them is calculated using results of reservoir simulation model calculation. Similarly, variation of the average reservoir pressure over time is estimated. Knowing the location of each well and the distance between all wells, it is possible to estimate the minimum number of wells needed to cover the entire field with a well test grid with a given maximum distance from every well to the nearest tested well. The obtained dependences of reservoir pressure deviation from distance and time allow to estimate the minimum required number of well tests to calculate a reservoir pressure map with a specified maximum permissible mean error. It is also possible to determine the optimal frequency of well tests on the same well, which allows to form an optimal well test program for reservoir pressure mapping. The application of the proposed method for estimating the required number of well tests per year and the frequency of well tests on the same well to achieve a given maximum permissible mean error is considered using a Western Siberian oil field as an example. The conclusion is made about the choice between the increase in the number of grid wells and the frequency of well tests in conditions of limiting the total number of well tests per year.

References

1. Earlougher R.C. Jr., Advances in well test analysis, SPE Monograph Series, 1977, V. 5., 264 p.

2. Materon Zh., Fundamentals of applied geostatistics (translation from French), Moscow – Izhevsk: Publ. of Institute of Computer Research, 2009, 460 p.

3. Baykov V.A. et al., Matematicheskaya geologiya (Mathematical geology), Part 1. Vvedenie v geostatistiku (Introduction to geostatistics), Moscow – Izhevsk:: Publ. of Institute of Computer Research, 2012, 228 p.

4. Asalkhuzina G.F., Davletbaev A.Ya., Khabibullin I.L., Modeling of the reservoir pressure difference between injection and production wells in low permeable reservoirs (In Russ.), Vestnik Bashkirskogo Universiteta, 2016, V. 21, no. 3, pp. 537–544.The paper discusses a method of defining a relationship between the quantity and frequency of well tests on one hand and pressure map accuracy on the other hand. Dependence of average reservoir pressure deviation between two wells from distance between them is calculated using results of reservoir simulation model calculation. Similarly, variation of the average reservoir pressure over time is estimated. Knowing the location of each well and the distance between all wells, it is possible to estimate the minimum number of wells needed to cover the entire field with a well test grid with a given maximum distance from every well to the nearest tested well. The obtained dependences of reservoir pressure deviation from distance and time allow to estimate the minimum required number of well tests to calculate a reservoir pressure map with a specified maximum permissible mean error. It is also possible to determine the optimal frequency of well tests on the same well, which allows to form an optimal well test program for reservoir pressure mapping. The application of the proposed method for estimating the required number of well tests per year and the frequency of well tests on the same well to achieve a given maximum permissible mean error is considered using a Western Siberian oil field as an example. The conclusion is made about the choice between the increase in the number of grid wells and the frequency of well tests in conditions of limiting the total number of well tests per year.

References

1. Earlougher R.C. Jr., Advances in well test analysis, SPE Monograph Series, 1977, V. 5., 264 p.

2. Materon Zh., Fundamentals of applied geostatistics (translation from French), Moscow – Izhevsk: Publ. of Institute of Computer Research, 2009, 460 p.

3. Baykov V.A. et al., Matematicheskaya geologiya (Mathematical geology), Part 1. Vvedenie v geostatistiku (Introduction to geostatistics), Moscow – Izhevsk:: Publ. of Institute of Computer Research, 2012, 228 p.

4. Asalkhuzina G.F., Davletbaev A.Ya., Khabibullin I.L., Modeling of the reservoir pressure difference between injection and production wells in low permeable reservoirs (In Russ.), Vestnik Bashkirskogo Universiteta, 2016, V. 21, no. 3, pp. 537–544.