# US 11,905,807 B2 · Workflow to model and condition water distribution in a hydrocarbon reservoir > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,905,807 B2 - Document ID: US11905807B2 - Status: Granted - Kind: B2 - Application number: 17/363,706 - Filed: 2021-06-30 - Published: 2023-01-05 - Granted: 2024-02-20 - Earliest claimed: 2021-06-30 - Assignees: Saudi Arabian Oil Company - Applicants: Saudi Arabian Oil Company - Inventors: Ahmed Moustafa Abdel Wahab M. Kassem; Nawaf Abdulrahman A Alghamdi; Badr Saeed Badghaish - Web page: https://patentgrep.com/patent/US11905807B2 ## CPC - E21B 43/20: Displacing by water - E21B 49/00: Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells - E21B 43/267: reinforcing fractures by propping - G01V 9/02: Determining existence or flow of underground water - G01V 20/00: Geomodelling in general - E21B 2200/20: Computer models or simulations, e.g. for reservoirs under production, drill bits - 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) ## Abstract A method includes determining a free water level in the reservoir, analyzing a free water pressure trend of the free water phase, determining a presence of anomalous pressures and salinities within the free water phase, determining whether gas down to models and water up to models fit the reservoir, determining a bi-modal pore throat distribution of the plurality of pores within the reservoir, and generating a difference map to model the water distribution in the reservoir. ## Claims ### Claim 1 A method for modeling water distribution in a reservoir having a gas phase, a free water phase, and a plurality of pores, the method comprising: determining a free water level in the reservoir; analyzing a free water pressure trend of the free water phase; determining a presence of anomalous pressures and salinities within the free water phase; determining whether gas down to models and water up to models fit the reservoir; determining a bi-modal pore throat distribution of the plurality of pores within the reservoir; generating a difference map to model the water distribution in the reservoir; determining a top pay zone of the reservoir using the difference map, wherein the top pay zone is a portion of the reservoir where the gas phase is located; and drilling a well into the top pay zone of the reservoir to produce gas using the well. ### Claim 2 (depends on 1) The method of claim 1, wherein the difference map models the top pay zone for a complex capillary pressure effect in a complex hydrodynamic dipping surface. ### Claim 3 (depends on 1) The method of claim 1, wherein the difference map models the top pay zone for a single capillary pressure effect in a complex hydrodynamic dipping surface. ### Claim 4 (depends on 1) The method of claim 1, wherein the free water pressure trend is analyzed by comparing the free water pressure trend to a reservoir pressure trend. ### Claim 5 (depends on 4) The method of claim 4, wherein the free water pressure trend is analyzed by comparing the free water pressure trend to a pro-graditional pattern. ### Claim 6 (depends on 5) The method of claim 5, wherein the free water pressure trend is analyzed by comparing the free water pressure trend to a hydrostatic pressure trend. ### Claim 7 (depends on 6) The method of claim 6, further comprising: determining an age of the free water phase. ### Claim 8 (depends on 7) The method of claim 7, further comprising: determining whether the age of the free water phase is dated to a most recent extensive diagenetic process. ### Claim 9 (depends on 8) The method of claim 8, further comprising: determining if a gas water contact shows a dipping trend wherein the gas water contact is a location in the reservoir located where the free water phase meets the gas phase. ### Claim 10 (depends on 9) The method of claim 9, further comprising: creating an adjusted inclined gas water contact to fit the gas down to models and the water up to models. ### Claim 11 A non-transitory computer readable medium storing instructions for modeling water distribution in a reservoir having a gas phase, a free water phase, and a plurality of pores executable by a computer processor, the instructions comprising functionality for: determining a free water level in the reservoir; analyzing a free water pressure trend of the free water phase; determining a presence of anomalous pressures and salinities within the free water phase; determining whether gas down to models and water up to models fit the reservoir; determining a bi-modal pore throat distribution of the plurality of pores within the reservoir; generating a difference map to model the water distribution in the reservoir. ### Claim 12 (depends on 11) The non-transitory computer readable medium of claim 11, wherein the free water pressure trend is analyzed by comparing the free water pressure trend to a reservoir pressure trend. ### Claim 13 (depends on 12) The non-transitory computer readable medium of claim 12, wherein the free water pressure trend is analyzed by comparing the free water pressure trend to a pro-graditional pattern. ### Claim 14 (depends on 13) The non-transitory computer readable medium of claim 13, wherein the free water pressure trend is analyzed by comparing the free water pressure trend to a hydrostatic pressure trend. ### Claim 15 (depends on 14) The non-transitory computer readable medium of claim 14, wherein the instructions further comprise functionality for: determining an age of the free water phase. ### Claim 16 (depends on 15) The non-transitory computer readable medium of claim 15, wherein the instructions further comprise functionality for: determining whether the age of the free water phase is dated to a most recent extensive diagenetic process. ### Claim 17 (depends on 16) The non-transitory computer readable medium of claim 16, wherein the instructions further comprise functionality for: determining if a gas water contact shows a dipping trend wherein the gas water contact is a location in the reservoir located where the free water phase meets the gas phase. ### Claim 18 (depends on 17) The non-transitory computer readable medium of claim 17, wherein the instructions further comprise functionality for: creating an adjusted inclined gas water contact to fit the gas down to models and the water up to models. ### Claim 19 (depends on 18) The non-transitory computer readable medium of claim 18, wherein the difference map models a top pay zone for a complex capillary pressure effect in a complex hydrodynamic dipping surface. ### Claim 20 (depends on 18) The non-transitory computer readable medium of claim 18, wherein the difference map models a top pay zone for a single capillary pressure effect in a complex hydrodynamic dipping surface.