Bp Corporation North America Inc.

Herbert Sebastian

John R Adams

Bryan Dotson

Harun Ates

Yuanlin Jiang

Yafes Abacioglu

Siyavash Motealleh

A computer system and method of automatically generating a Local Grid Refinement (LGR) gridded model of a gas reservoir. A geologic file includes information identifying the locations of one or more wells according to root grid cells within a volume of the earth to be modeled. User inputs specify the number of hydraulic fractures from each well, and such parameters as the fracture length, etc. User inputs also specify the number of 'splits' of the root grid cells containing hydraulic fractures; those root grid cells are then split into finer resolution grid cells of increasing width within the root grid cells containing the fractures. For horizontal wells, user inputs indicate the number of splits of root grid cells containing the lateral portions of the wellbore. Non-orthogonal and complex fractures are processed by a 'nested' LGR approach. Geologic properties are assigned to each grid cell, with a tensorial adjustment included for non-orthogonal fractures, and the resulting model is available for simulation.

Automated generation of local grid refinement at hydraulic fractures for simulation of tight gas reservoirs

A new approach is disclosed for measuring the pressure of tight gas reservoirs, using information obtain from continuous injection prior to hydraulic fracture stimulation. The technique can be obtained utilizing either bottom-hole or surface pressure gauges and properly instrumented surface injection pumps. The analysis is completed by plotting injection and rate data in a specialized form from terms arranged in Darcy's radial flow equation to obtain a curve or trend. The key component to proper application of this technique is to obtain both baseline and one or more calibration data sets. These calibration data sets are obtained by either increasing or decreasing the injection pressure and/or rate from the baseline data. Initial reservoir pressure is assumed, but the calibration data indicates if the guess was too high or low. Accurate estimates of reservoir pressure may be obtained in a few iterations.

Method of determining reservoir pressure

Growing community of inventors

Cypress, TX, United States of America

Herbert Sebastian