# US 10,370,965 B2 · Method for determining a permeability or mobility of a radial flow response of a reservoir > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,370,965 B2 - Document ID: US10370965B2 - Status: Granted - Kind: B2 - Application number: 13/372,457 - Filed: 2012-02-13 - Published: 2013-08-15 - Granted: 2019-08-06 - Earliest claimed: 2012-02-13 - Assignees: Schlumberger Technology Corporation - Applicants: Peter S. Hegeman; Mustafa Onur - Inventors: Peter S. Hegeman; Mustafa Onur - Web page: https://patentgrep.com/patent/US10370965B2 ## CPC - E21B 49/088: {combined with sampling} - G01V 11/00: Prospecting or detecting by methods combining techniques covered by two or more of main groups G01V1/00 - G01V9/00 - G06F 17/00: Digital computing or data processing equipment or methods, specially adapted for specific functions (information retrieval, database structures or file system structures therefor G06F16/00) - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract A system and method determine formation permeability and/or at least one property indicative of formation permeability of a subsurface geological reservoir having radial-flow. Pressure data is obtained with an observation probe during a formation test, wherein the observation probe is located at a setting position within an open hole wellbore formed within the reservoir. The system and method measure radial-flow response of the reservoir at or adjacent to the setting position of the observation probe by analyzing the collected pressure data. The formation permeability and/or at least one property indicative of the permeability of the reservoir is determined based on the measured radial-flow response of the reservoir at or adjacent to the observation probe. ## Claims ### Claim 1 A method comprising: positioning a formation testing tool within a wellbore formed within a subsurface reservoir, wherein the tool has an observation probe configured to obtain pressure data; analyzing via the formation testing tool the obtained pressure data to determine when radial flow is reached; determining via the formation testing tool vertical permeability or vertical mobility of the reservoir based on when radial flow is reached and a Horner analysis of the subsurface reservoir at or adjacent to the observation probe. ### Claim 2 (depends on 1) The method according to claim 1, wherein the reservoir has three-dimensional permeability anisotropy. ### Claim 3 (depends on 1) The method according to claim 1, further comprising: determining via the formation testing tool horizontal permeability or horizontal mobility of the reservoir based on when radial flow is reached and a Homer analysis of the subsurface reservoir at or adjacent to the observation probe. ### Claim 4 (depends on 1) The method according to claim 1, wherein the vertical permeability or the vertical mobility of the reservoir is determined based on a graphical interpretation of pressure data collected by the observation probe. ### Claim 5 (depends on 1) The method according to claim 1, wherein the determining the vertical permeability or the vertical mobility is accomplished without an initial estimate of model parameters. ### Claim 6 (depends on 1) The method according to claim 1, wherein the tool has a second probe or two packer elements configured to withdraw or inject fluid into the subsurface reservoir. ### Claim 7 (depends on 1) The method according to claim 1, wherein the tool is configured to conduct an interval pressure transient test (IPTT) of the subsurface reservoir. ### Claim 8 A method comprising: obtaining pressure measurements with an observation probe of a formation testing tool during a pressure drawdown test or pressure buildup test, wherein the observation probe is located at a setting position within a wellbore formed within a subsurface geological reservoir and the wellbore is an open hole wellbore; determining via the formation testing tool when radial flow of the reservoir at or adjacent to the setting position of the observation probe is reached by analyzing the collected pressure data; determining via the formation testing tool horizontal permeability or horizontal mobility of the reservoir based on when radial flow is reached and a Homer analysis of the reservoir at or adjacent to the observation probe; and determining via the formation testing tool vertical permeability or vertical mobility of the reservoir based on when radial flow is reached and a Horner analysis of the reservoir at or adjacent to the observation probe. ### Claim 9 (depends on 8) The method according to claim 8, wherein the setting position is at a portion of the wellbore that is inclined at an angle greater than 5 degrees and less than 85 degrees. ### Claim 10 (depends on 8) The method according to claim 8, wherein the horizontal permeability, the horizontal mobility, the vertical mobility and the vertical permeability are determined without use of an iterative method. ### Claim 11 (depends on 8) The method according to claim 8, wherein the horizontal permeability, the horizontal mobility, the vertical mobility and the vertical permeability are determined based on a graphical method. ### Claim 12 (depends on 11) The method according to claim 11, wherein the graphical method results in a linear function with respect to the horizontal permeability, the horizontal mobility, the vertical mobility or the vertical permeability. ### Claim 13 (depends on 8) The method according to claim 8, further comprising: determining formation permeability of the reservoir via a direct analytical solution based on the collected pressure data.