# US 2025/0146403 A1 · Method and system for monitoring a well treatment > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0146403 A1 - Document ID: US20250146403A1 - Status: Published application - Kind: A1 - Application number: 18/387,971 - Filed: 2023-11-08 - Published: 2025-05-08 - Earliest claimed: 2023-11-08 - Assignees: Resman AS - Applicants: Resman AS - Inventors: Olaf Kristoffer HUSEBY; Christopher FREDD; John Daniels; Douglas Alexander Pipchuk - Web page: https://patentgrep.com/patent/US20250146403A1 ## CPC - E21B 47/11: using tracers; using radioactivity - E21B 43/25: Methods for stimulating production {(by vibrating earth formations E21B43/003)} - 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 ## Abstract The invention may provide methods of characterising and/or optimising a well treatment. The method comprises calculating, estimating and/or determining at least one spatial or temporal tracer distribution moment for at least one tracer in a well before the well treatment and calculating, estimating and/or determining at least one spatial or temporal tracer distribution moment for the at least one tracer introduced into the well at a later stage or later portion of the well treatment or after at least well treatment stage has been completed or approaching completion. The method comprises comparing the at least one spatial or temporal tracer distribution moment of the tracers to estimate at least one characteristic of the well treatment. ## Claims ### Claim 1 A method of characterising a well treatment, the method comprising: calculating, estimating and/or determining at least one spatial or temporal tracer distribution moment for at least one tracer in the well before a well treatment and/or in an early portion of a well treatment; calculating, estimating and/or determining at least one spatial or temporal tracer distribution moment for the at least one tracer introduced into the well at a later stage or later portion of the well treatment or after at least well treatment stage has been completed or approaching completion; comparing the at least one spatial or temporal tracer distribution moment of the at least two tracers to estimate at least one characteristic of the well treatment. ### Claim 2 (depends on 1) The method according to claim 1 wherein the well treatment is selected from the group comprising well stimulation treatment, acidizing treatment, matrix acidizing treatment, fracturing treatment, hydraulic fracturing treatment, fracture acidizing treatment, enhanced oil recovery treatment, and/or water control treatment. ### Claim 3 (depends on 1) The method according to claim 1 comprising introducing at least one tracer into a well before and/or with the well treatment. ### Claim 4 (depends on 1) The method according to claim 1 comprising calculating, estimating and/or determining at least one spatial or temporal tracer distribution moment for at least one tracer in the well before the well treatment from historical tracer injection and/or production associated with production from the reservoir. ### Claim 5 (depends on 1) The method according to claim 1 comprising introducing each of the two or more tracers into the well by injecting the two or more tracers into the well from surface or from a downhole device. ### Claim 6 (depends on 1) The method according to claim 1 comprising introducing at least one tracer into the well by releasing tracer from tracer sources installed, arranged or positioned in the well. ### Claim 7 (depends on 1) The method according to claim 1 comprising introducing two or more tracer into the same injector well or different injector wells. ### Claim 8 (depends on 1) The method according to claim 1 comprising introducing two or more tracers into an injector well, a production well or a combination of at least one injector well and production well. ### Claim 9 (depends on 1) The method according to claim 1 comprising associating a difference or change between the at least one spatial or temporal tracer distribution moment for the two of more tracers with a characteristic of the well treatment. ### Claim 10 (depends on 1) The method according to claim 1 wherein the at least one moment is selected from a zero order moment, a first order moment, a second order moment, and/or a higher order moment. ### Claim 11 (depends on 1) The method according to claim 1 comprising analysing a measured tracer concentration data set for each of the two or more tracers wherein the measured tracer concentration data set is tracer concentration as a function of time, tracer concentration as a function of space and/or a residence time distribution. ### Claim 12 (depends on 1) The method according to claim 1 comprising creating a tracer curve from the measured tracer concentration as a function of time and comparing the tracer curves of the two or more tracers to assess the well stimulation treatment. ### Claim 13 (depends on 12) The method according to claim 12 comprising calculating an area under the tracer curve to calculate the at least one moment of measured tracer data set and comparing the area under the tracer curve for each of the two or more tracers. ### Claim 14 (depends on 1) The method according to claim 1 comprising calculating a swept volume for each of the two or more tracers and comparing the swept volume of each of the two or more tracers. ### Claim 15 (depends on 1) The method according to claim 1 comprising calculating an arrival time characteristic for each of the two or more tracers and comparing the arrival time characteristic for the two or more tracers to assess a magnitude of change associated with the well stimulation treatment. ### Claim 16 (depends on 1) The method according to claim 1 comprising analysing the measured tracer concentration data to characterise and/or identify a flow type pattern selected from the group comprising a face dissolution, conical wormhole, dominant wormhole, ramified wormhole, uniform dissolution, an etch pattern, a near-wellbore dissolution, heterogeneous etch channel, channels, planar fractures, complex fractures and/or cracks. ### Claim 17 (depends on 1) The method according to claim 1 comprising identifying and/or characterising flow patterns by comparing a measured tracer response curve with a library of tracer response curves associated with various flow type patterns. ### Claim 18 (depends on 1) The method according to claim 1 comprising improving production forecasting based on characterising flow patterns after the well treatment. ### Claim 19 (depends on 1) The method according to claim 1 wherein the tracers are selected from the group comprising water tracers, oil tracers, gas tracers, or tracers deployed as solids such as in a polymer matrix, impregnated proppant, or fluid loss material. ### Claim 20 (depends on 1) The method according to claim 1 introducing at least one distinctive tracer into a well before and/or with a further well treatment and introducing a different tracer into the well at a later stage or later portion of the well treatment or after at least well treatment stage has been completed or approaching completion and comparing the at least one spatial or temporal moment of the tracers to estimate at least one characteristic of the further well treatment. ### Claim 21 A method of optimising a well treatment, the method comprising: calculating, estimating and/or determining at least one spatial or temporal moment for at least one tracer in the well before the well treatment and/or in an early portion of the well treatment; calculating, estimating and/or determining at least one spatial or temporal moment for the at least one tracer introduced into the well at a later stage or later portion of the well profile modification treatment or after at least well treatment stage has been completed or approaching completion; comparing the at least one spatial or temporal moment of the at least two tracers to estimate at least one characteristic of the well treatment. ### Claim 22 (depends on 21) The method according to claim 21 comprising optimising the well treatment by adjusting one or more parameters selected from the group comprising stimulation fluid type, fluid viscosity, fluid reactivity, acid concentration, additive concentration, injection volume, injection rates, pulsing, proppant concentrations, fluid loss additive concentration and/or diverting agents. ### Claim 23 (depends on 21) The method according to claim 21 comprising characterising changes in reservoir flow patterns and optimising the well treatment by adjusting additional treatment and/or changing the treatment design in subsequent stages or subsequent wells. ### Claim 24 An interpretation method for a well treatment of a well comprising; providing tracer data from a producing well after a well treatment and/or in the early portion of the well treatment; wherein the tracer data comprises tracer concentration over time of two or more tracers in the production flow; wherein the two or more tracers were introduced into the well at known times of the well treatment; analysing the tracer data to estimate at least one characteristic of the well treatment based on the presence and/or concentration of tracers in the samples. ### Claim 25 A system for characterising and/or optimising a well treatment, the system comprises: two or more tracer sources each with a distinct tracer material; at least one tracer release mechanism; at least one well stimulation fluid; at least one pump apparatus to pump or inject the at least one well stimulation fluid; and at least one sampling device configured to collect at least one sample of well fluid at a known sampling location.