Method and device for determining initial mineral content in diagenesis process and electronic equipment
By combining sedimentary environment analysis, petrological testing and diagenetic numerical simulation methods, the problem of low prediction accuracy of initial mineral content in diagenesis in the prior art is solved, and accurate recovery and accurate prediction of mineral content in diagenesis are achieved.
Patent Information
- Application Number
- CN202311283045.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-09-30
- Publication Date
- 2025-04-01
AI Technical Summary
The prior art has low accuracy when predicting the initial mineral content during diagenesis, and the method is limited to dense reservoirs and has a limited range of use.
The initial mineral type is initially inferred based on the sedimentary environment, substance source and lithophagocytic conditions of the reservoir, combined with petrological test analysis and diagenetic sequence, and reversed the initial mineral type and content, and performed diagenetic numerical simulation, and gradually adjusted the initial mineral content until the error is within the accepted range.
The accurate quantitative recovery of the initial mineral content during diagenesis is achieved, the accuracy of the mineral transformation process is improved, the problems of long diagenesis time, many uncertain factors, and difficulty in pore evolution recovery are overcome, and the porosity evaluation and prediction accuracy is improved.
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Abstract
Description
Technical Field
[0001] The present invention belongs to the discipline of petroleum geology and relates to the technical field of oil and gas exploration, and specifically relates to a method, device and electronic equipment for determining the initial mineral content in the diagenesis process, which is a study on the restoration of the diagenetic evolution process and is used to determine the initial mineral content in the diagenetic simulation process. Background Art
[0002] With the development of diagenesis research, the restoration of reservoir diagenetic evolution has changed from qualitative and semi-quantitative to quantitative. In the study of diagenetic evolution, a relatively effective research method currently recognized is: (1) based on a series of petrological tests and analyses such as thin sections, scanning electron microscopy, isotopes, and fluid inclusions, identify typical diagenesis, determine diagenetic sequences, and generalize diagenetic processes; (2) according to typical diagenetic events, the diagenetic process is divided into several continuous diagenetic stages such as early diagenesis, organic acid filling, hydrothermal filling, and deep fluid environment, and physical simulation experiments or numerical simulations of high-temperature and high-pressure fluid-rock interactions are carried out to analyze the mineral dissolution, precipitation, and transformation laws that occur in different diagenetic stages under different temperature, pressure, fluid, and lithology conditions; (3) the reactions of each stage are connected in time to reconstruct the entire diagenetic evolution process. However, the restoration of the diagenetic process is "using the present to discuss the past". The initial conditions are no longer available, and the initial conditions need to be inferred from the current test data. The inference process is highly uncertain and artificial.
[0003] In addition, some scholars have used seismic data to invert reservoir rock components to determine mineral content. The specific steps are: (1) X-ray diffraction whole rock analysis to establish the relative content characteristic curve of each mineral component in dense rock; (2) Reconstruct the relative content characteristic curve of each mineral component in dense rock and the brittleness index characteristic curve; (3) Using the reconstructed relative content characteristic curve of each mineral component in dense rock and the brittleness index characteristic curve as constraints, perform seismic waveform indication inversion to obtain the inversion data body of the relative content and brittleness index of each mineral component in dense rock. This method does not take into account the chemical reactions in the process of diagenesis and evolution, and is only applicable to dense reservoirs, with a small scope of application. Summary of the invention
[0004] The present application provides a method, device and electronic device for determining the initial mineral content in the rock formation process, so as to solve the above-mentioned technical problem that the prediction accuracy of the prior art is not high.
[0005] According to one aspect of the present application, an embodiment provides a method for determining the initial mineral content in a diagenetic process, comprising:
[0006] Based on the sedimentary environment, provenance and lithofacies conditions of the reservoir, the initial mineral type is preliminarily inferred;
[0007] Conduct petrological testing and analysis on current samples to determine the diagenetic sequence and current mineral types and contents; and, based on the diagenetic sequence and mineral transformation relationship, infer the initial diagenetic mineral types and contents, wherein the inferring of the diagenetic mineral types and contents at the very beginning of the diagenesis and at the beginning of each diagenetic stage;
[0008] Carry out numerical simulation of diagenesis in the first diagenesis stage based on the set conditions;
[0009] The result at the end of the previous diagenetic stage is used as the initial condition of the next diagenetic stage, and the diagenetic numerical simulation is repeated until the simulation of all diagenetic stages is completed;
[0010] The mineral content value after the diagenetic numerical simulation is compared with the mineral content value calculated theoretically by the traditional method. If the error is within an acceptable range, the initial value inferred by the diagenetic numerical simulation is the initial mineral content of the diagenetic process.
[0011] In one embodiment, petrological testing and analysis are performed on current samples to determine the diagenetic sequence and the diagenetic evolution process of the reservoir; the determination of the diagenetic evolution process of the reservoir is based on at least one of rock thin section identification, fluid inclusion analysis, isotope testing, and cathodoluminescence testing, and combined with burial history and thermal history to determine the diagenetic fluid filling time, porosity evolution process and mineral transformation process of the reservoir at a certain stage.
[0012] In one embodiment, the petrological test analysis includes one or more of XRD, XRF, thin section, cathodoluminescence, and fluid inclusion testing.
[0013] In one embodiment, the conditions set in the diagenetic numerical simulation include: one or more of paleo-temperature, paleo-pressure and paleo-fluid corresponding to the diagenetic stage.
[0014] In one embodiment, the conditions are set based on the temperature, pressure and fluid type at a certain time during the diagenetic evolution process determined by reservoir thermal history, burial history, well logging, mud logging data, trace elements, carbon isotope or oxygen isotope testing.
[0015] In one embodiment, the results at the end of the previous diagenetic stage include one or both of mineral content and fluid water chemical conditions.
[0016] In one embodiment, when comparing the mineral content value after the diagenetic numerical simulation with the mineral content value theoretically calculated by the traditional method, if the error exceeds the acceptable range, the initial mineral content in the diagenetic numerical simulation is adjusted, and the simulation is performed again until the simulation result is within the error range. The simulation ends and the initial mineral content inferred by the simulation is obtained.
[0017] According to one aspect of the present application, an embodiment provides a device for determining the initial mineral content in a diagenetic process, comprising:
[0018] The preliminary inference module is used to preliminarily infer the initial mineral type based on the sedimentary environment, provenance and lithofacies conditions of the reservoir;
[0019] The determination module is used to perform petrological tests and analyses on present-day samples, determine the diagenetic sequence, and determine the present-day mineral types and contents;
[0020] A reverse inference module is used to reversely infer the initial diagenetic mineral type and content based on the diagenetic sequence and mineral transformation relationship, wherein the diagenetic mineral type and content at the initial stage of diagenesis and the initial stage of each diagenetic stage are reversed;
[0021] A simulation module, used to perform numerical simulation of the first diagenetic stage based on the set conditions;
[0022] A repeated simulation module is used to use the result at the end of the previous diagenesis stage as the initial condition of the next diagenesis stage, and repeat the diagenesis numerical simulation until the simulation of all diagenesis stages is completed; and
[0023] The comparison module is used to compare the mineral content value after the diagenetic numerical simulation with the mineral content value calculated theoretically by the traditional method. If the error is within the acceptable range, the initial value inferred by the diagenetic numerical simulation is the initial mineral content of the diagenetic process.
[0024] According to one aspect of the present application, an embodiment provides an electronic device, including:
[0025] Memory; and
[0026] processor;
[0027] Wherein, the memory is used to store one or more computer instructions; the one or more computer instructions are executed by the processor to implement the method for determining the initial mineral content in the rock formation process as described in any one of the above items.
[0028] According to one aspect of the present application, an embodiment provides a readable storage medium having computer instructions stored thereon; wherein, when the computer instructions are executed by a processor, a method for determining the initial mineral content in the diagenesis process as described in any one of the above items is implemented.
[0029] The technical solution of the above-mentioned embodiment of the present application adopts a method for determining the initial mineral content in the diagenesis process, which can quantitatively restore the change process of each mineral content in a certain diagenesis stage. Therefore, combined with the diagenetic events and chemical reaction mechanisms involved in the diagenesis stage, the mineral content in the diagenesis stage can be accurately corrected, thereby improving the accuracy of the mineral transformation process and ultimately restoring the initial mineral content value of the diagenesis.
[0030] In general, the technical solutions of the above embodiments are based on geochemistry, mineralogy and numerical analysis theories, and use numerical simulation to determine the initial mineral types and contents at the beginning of diagenesis and each subsequent diagenetic stage, thereby constraining the recovery of each diagenetic stage and even the entire diagenetic process, thereby improving the accuracy of diagenetic process recovery, and can overcome the problems of long diagenetic time, many uncertain factors, and difficult pore evolution recovery, thereby improving the accuracy of porosity evaluation and prediction. BRIEF DESCRIPTION OF THE DRAWINGS
[0031] Figure 1 is a flow chart of a method for determining the initial mineral content during rock formation in an embodiment;
[0032] Figure 2 is a flowchart of a method for determining the initial mineral content in a rock formation process in an embodiment;
[0033] Figure 3 is a graph showing changes in mineral content and porosity of carbonate reservoirs at different diagenetic stages in an embodiment;
[0034] Figure 4 The present invention is a schematic diagram of the structure of a device for determining the initial mineral content during the rock formation process in an embodiment. DETAILED DESCRIPTION
[0035] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0036] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only embodiments of a part of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present application.
[0037] It should be noted that the terms "first", "second" etc. in the present application are used to distinguish similar objects, and need not be used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged in appropriate circumstances, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, the process, method, system, product or equipment comprising a series of steps or units need not be limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment.
[0038] It should be understood that when an element (such as a layer, film, region, or substrate) is described as being "on" another element, the element may be directly on the other element, or there may be an intermediate element. Moreover, in this application, when an element is described as being "connected" to another element, the element may be "directly connected" to the other element, or "connected" to the other element through a third element.
[0039] Embodiment 1
[0040] Please refer to Figure 1 , one embodiment provides a method for determining the initial mineral content in a diagenetic process, comprising the following steps:
[0041] S1. Based on the sedimentary environment, provenance and lithofacies conditions of the reservoir, the initial mineral type is preliminarily inferred.
[0042] S2. Conduct petrological testing and analysis on current samples to determine the diagenetic sequence and current mineral types and contents; and, based on the diagenetic sequence and mineral transformation relationships, infer the initial diagenetic mineral types and contents, wherein the diagenetic mineral types and contents at the earliest stage of diagenesis and at the beginning of each diagenetic stage are inferred.
[0043] In one embodiment of step S2, petrological testing and analysis are performed on the current samples to determine the diagenetic sequence and the diagenetic evolution process of the reservoir; the determination of the diagenetic evolution process of the reservoir is based on at least one of rock thin section identification, fluid inclusion analysis, isotope testing, and cathodoluminescence testing, and combined with burial history and thermal history to determine the diagenetic fluid filling time, porosity evolution process and mineral transformation process of the reservoir at a certain stage.
[0044] In one embodiment, the petrological test analysis includes one or more of XRD, XRF, thin section, cathodoluminescence, and fluid inclusion testing.
[0045] S3. Performing a diagenetic numerical simulation of the first diagenetic stage based on the set conditions. Preferably, the conditions include: one or more of paleo-temperature, paleo-pressure and paleo-fluid corresponding to the diagenetic stage.
[0046] In one embodiment, the conditions are set based on the temperature, pressure and fluid type at a certain time during the diagenetic evolution process determined by reservoir thermal history, burial history, well logging, mud logging data, trace elements, carbon isotope or oxygen isotope testing.
[0047] S4. Using the result at the end of the previous diagenetic stage as the initial condition for the next diagenetic stage, repeat the diagenetic numerical simulation until the simulation of all diagenetic stages is completed. The result at the end of the previous diagenetic stage includes one or two of the mineral content and the fluid water chemical condition. The next stage simulation is performed again using the mineral content, fluid water chemical condition, etc. after the end of the previous diagenetic stage as the initial condition, and the simulation is repeated.
[0048] S5. Compare the mineral content value after the diagenetic numerical simulation with the mineral content value calculated theoretically using the traditional method.
[0049] If the error is within the acceptable range, the initial value inferred by the diagenetic numerical simulation is the initial mineral content of the diagenetic process. If the error exceeds the acceptable range, the initial mineral content in the diagenetic numerical simulation is adjusted and the simulation is repeated until the simulation result is within the error range. The simulation ends and the initial mineral content inferred by the simulation is obtained.
[0050] The method of determining the initial mineral content in the diagenesis process of the present invention combines relevant testing methods to summarize the reservoir diagenesis evolution process, and then simulates each diagenesis stage by diagenetic numerical simulation (implemented by software simulation), and quantitatively restores the mineral transformation process in the diagenesis stage. By comparing the simulated mineral content with the current mineral content, the initial mineral content is corrected, and the simulation is repeated to obtain an accurate initial mineral content value.
[0051] Embodiment 2
[0052] Please refer to Figure 2 , Figure 3 An embodiment provides a method for determining the initial mineral content in the diagenesis process. The following will explain the technical solution of the present invention with the ideas of the inventor, which will help those skilled in the art to be familiar with the ideas of the present invention. Among them, some technical points are explained in detail so that those skilled in the art can fully understand the technical solution of the present invention.
[0053] A method for determining the initial mineral content in the diagenesis process adopts the following manner: preliminarily infer the initial mineral type according to the sedimentary environment, material source and lithofacies conditions; conduct XRD, XRF, thin section, cathode luminescence, fluid inclusion and other tests on the current samples to determine the diagenetic sequence, determine the typical diagenetic events, divide the diagenetic stages, and determine the current mineral type and content; reversely infer the diagenetic mineral type and content at the initial stage of diagenesis and each diagenetic stage according to the diagenetic sequence and mineral transformation relationship; simulate and calculate the first diagenetic stage, and take the mineral content at the end of the first diagenetic stage as the initial content of the second stage, and so on, until the simulation of all diagenetic stages is completed; compare the simulated value at the end of each stage with the mineral content inferred by the test, and compare the final simulation result with the current measured value; if it is within the error range, then end, and the inferred initial value is the initial mineral content of diagenesis; if the error is large, adjust the initial content according to the situation, simulate again, until the simulation result is within the error range, and end the simulation.
[0054] In detail, the above method for determining the initial mineral content in the diagenesis process includes the following steps:
[0055] (1) Based on the well logging data of the reservoir combined with the sediment source characteristics and lithofacies conditions of the region, the lithofacies type and initial mineral type are preliminarily inferred.
[0056] (2) Determine the current mineral content based on the test data of XRD, XRF, thin section, cathodoluminescence, fluid inclusions, etc. of the reservoir, clarify the characteristics of diagenesis, dissect the diagenetic evolution process, and calculate the initial mineral content based on the chemical reaction mechanism of diagenesis.
[0057] In one embodiment, step (2) involves determining the reservoir diagenetic evolution process, which is based on rock thin section identification, fluid inclusion analysis, isotope testing and cathodoluminescence testing combined with burial history and thermal history to determine the diagenetic fluid filling time, porosity evolution process and mineral transformation process of the reservoir at a certain stage.
[0058] (3) Using numerical simulation methods, we set the paleotemperature, paleopressure, paleofluid and other conditions corresponding to the diagenetic stage, calculated the mineral content in the traditional way as the initial mineral conditions, and set the reaction time on a geological time scale to simulate the first diagenetic stage.
[0059] In one embodiment, the numerical simulation means is implemented by software, wherein the numerical simulation means includes numerical software such as TOUGHREACT or TOUGHSTONE that can be used for diagenetic effect simulation.
[0060] In one embodiment, the paleotemperature, paleopressure, and paleofluid conditions set in the numerical simulation are based on the thermal history, burial history, well logging, and mud logging data of the reservoir, as well as the temperature, pressure values and fluid types at a certain time during the diagenetic evolution process determined by tests of trace elements, carbon isotopes, oxygen isotopes, etc.
[0061] (4) Using numerical simulation methods, the next diagenetic stage is simulated with the mineral content, fluid water chemical conditions, etc. after the end of the previous diagenetic stage as the initial conditions and repeated until the entire diagenetic evolution process is simulated.
[0062] Among them, the restart block in the TOUGHREACT numerical simulation software can be used to simulate the next stage again and repeat it with the mineral content, fluid water chemical conditions, etc. after the end of the previous diagenetic stage as the initial conditions.
[0063] (5) According to the difference between the mineral content value after diagenetic numerical simulation and the mineral content value calculated by traditional theoretical method, combined with the diagenetic reaction mechanism, the initial mineral content set in the simulation is modified, and the diagenetic evolution simulation is carried out again.
[0064] (6) Based on the reservoir diagenetic evolution process, the initial mineral values are continuously modified and diagenetic numerical simulation is performed until the error is reduced to an acceptable range, and finally the initial mineral content of the diagenetic process is determined.
[0065] Compared with the traditional method of purely empirically inferring the initial mineral content, the method of determining the initial mineral content during the diagenesis process of the present invention fully considers the material balance during the diagenesis process and quantitatively calculates the change of mineral content over time. It can overcome the problems of long diagenesis time, many uncertain factors, and difficult recovery of pore evolution, thereby improving the accuracy of porosity evaluation and prediction.
[0066] Taking the deep carbonate reservoir of the Deng 4th Member in Anyue Gas Field in Sichuan Basin as an example, the method of determining the initial mineral content during diagenesis was adopted, and some data were provided in this example.
[0067] Through XRD, XRF, ordinary thin sections and other testing methods, the existing mineral types and mineral contents are determined as follows: dolomite content is 70%, calcite content is 5%, and quartz content is 25%. The reservoirs in this area are mainly dolomitized, recrystallized, cemented, dissolved, and compacted. There is hydrothermal filling during the diagenetic evolution process, and quartz precipitation is directly affected by hydrothermal fluids. The analysis of the chemical reaction mechanism speculates that the initial mineral content in this area is mainly calcite. The initial mineral calcite content is calculated to be 70% by traditional calculation methods. After numerical simulation using the initial calcite content of 70%, the dolomite content is 60.07% and the calcite content is 11.14%, which are quite different from the actual situation. The initial mineral content value is corrected by the chemical reaction mechanism and reaction results, and the simulation is repeated until the error range is narrowed to an acceptable range. Finally, the initial calcite content is determined to be 68.79%, and the dolomite content after numerical simulation reaction is 71.32%, and the calcite content is 4.71%, which improves the accuracy of diagenetic mineral conversion. Among them, Figure 3 It reflects the changes in mineral content and porosity in different diagenetic stages of carbonate reservoirs.
[0068] Embodiment 3
[0069] Please refer to Figure 2 One embodiment provides a method for determining the initial mineral content during diagenesis, using the following steps:
[0070] (1) Preliminary inference of initial mineral types; preferably, preliminary inference is made based on the sedimentary environment, provenance and lithofacies conditions.
[0071] (2) Perform petrological tests and analyses on current samples to determine the diagenetic sequence and the types and contents of current minerals. Specifically, perform XRD, XRF, thin section, cathode luminescence, fluid inclusion and other tests on current samples to determine the diagenetic sequence, identify typical diagenetic events, divide diagenetic stages, and determine the types and contents of current minerals.
[0072] (3) Inversely infer the initial diagenetic mineral types and contents. It is feasible to infer the initial diagenetic mineral types and contents at the beginning of diagenesis and each diagenetic stage based on the diagenetic sequence and mineral transformation relationship.
[0073] (4) Simulate and calculate the diagenetic evolution process in sequence. It is feasible to simulate and calculate the first diagenetic stage, and use the mineral content at the end of the first diagenetic stage as the initial content of the second stage, and so on, until the simulation of all diagenetic stages is completed.
[0074] (5) Compare the simulation results with the measured values: if they are within the error range, then end; if the error is large, adjust the initial content according to the situation, simulate again, until the simulation results are within the error range, then end the simulation. In detail, compare the simulation values at the end of each stage with the mineral content inferred from the test, and compare the final simulation results with the current measured values; if they are within the error range, then end, and the inferred initial value is the initial mineral content of the diagenesis; if the error is large, adjust the initial content according to the situation, simulate again, until the simulation results are within the error range, then end the simulation.
[0075] Compared with the traditional method of purely empirically inferring the initial mineral content, the method of determining the initial mineral content during the diagenesis process of the present invention fully considers the material balance during the diagenesis process and quantitatively calculates the change of mineral content over time. It can overcome the problems of long diagenesis time, many uncertain factors, and difficult recovery of pore evolution, thereby improving the accuracy of porosity evaluation and prediction.
[0076] Embodiment 4
[0077] Please refer to Figure 4 , one embodiment provides a device for determining the initial mineral content in a rock formation process, in the form of:
[0078] (1) The preliminary inference module 10 is used to preliminarily infer the initial mineral type based on the sedimentary environment, provenance and lithofacies conditions of the reservoir.
[0079] (2) The determination module 20 is used to perform petrological testing and analysis on the current samples, determine the diagenetic sequence, and determine the current mineral types and contents.
[0080] Among them, it involves determining the diagenetic evolution process of the reservoir; the determination of the diagenetic evolution process of the reservoir is based on at least one of rock thin section identification, fluid inclusion analysis, isotope testing, and cathodoluminescence testing, and combined with burial history and thermal history to determine the diagenetic fluid filling time, porosity evolution process and mineral transformation process of the reservoir at a certain stage.
[0081] In one embodiment, the petrological test analysis includes one or more of XRD, XRF, thin section, cathodoluminescence, and fluid inclusion testing.
[0082] (3) The reverse inference module 30 is used to reversely infer the initial diagenetic mineral type and content based on the diagenetic sequence and mineral transformation relationship, wherein the reverse inference is used to infer the diagenetic mineral type and content at the initial stage of diagenesis and at the beginning of each diagenetic stage.
[0083] (4) The simulation module 40 is used to perform numerical simulation of the first diagenesis stage based on the set conditions.
[0084] The conditions include: one or more of paleo-temperature, paleo-pressure and paleo-fluid corresponding to the diagenetic stage.
[0085] In one embodiment, the conditions are set based on the temperature, pressure and fluid type at a certain time during the diagenetic evolution process determined by reservoir thermal history, burial history, well logging, mud logging data, trace elements, carbon isotope or oxygen isotope testing.
[0086] (5) The repeated simulation module 50 is used to use the result at the end of the previous diagenetic stage as the initial condition of the next diagenetic stage, and repeat the diagenetic numerical simulation until the simulation of all diagenetic stages is completed.
[0087] In one embodiment, the result at the end of the previous diagenetic stage includes one or both of mineral content and fluid water chemical conditions. The subsequent stage simulation is performed again using the mineral content, fluid water chemical conditions, etc. after the end of the previous diagenetic stage as initial conditions, and the simulation is repeated.
[0088] (6) The comparison module 60 is used to compare the mineral content value after the diagenetic numerical simulation with the mineral content value calculated theoretically using the traditional method. If the error is within an acceptable range, the initial value inferred by the diagenetic numerical simulation is the initial mineral content of the diagenetic process.
[0089] Of course, there may be situations where the error exceeds the acceptable range. In one embodiment, if the error exceeds the acceptable range, the initial mineral content in the diagenetic numerical simulation is adjusted, and the simulation is repeated until the simulation result is within the error range. The simulation ends and the initial mineral content estimated by the simulation is obtained.
[0090] It should be noted that the above-mentioned device for determining the initial mineral content in the diagenesis process is used to implement the method for determining the initial mineral content in the diagenesis process in the above-mentioned embodiments, and each module in the device corresponds to each step in the method.
[0091] Embodiment 5
[0092] Based on the same inventive concept, an embodiment of the present application provides an electronic device, comprising: a memory and a processor; wherein the memory is used to store one or more computer instructions; the one or more computer instructions are executed by the processor to perform the method for determining the initial mineral content in the rock formation process described in any one of the above-mentioned embodiments.
[0093] Embodiment 6
[0094] Based on the same inventive concept, an embodiment of the present application provides a readable storage medium, on which computer instructions are stored; wherein, when the computer instructions are executed by a processor, the method for determining the initial mineral content in the diagenesis process as described in any one of the above embodiments is implemented.
[0095] Among them, the above one or more computer instructions can be formed into a program.
[0096] The above program can be run in the processor, or it can be stored in the memory (or computer-readable medium), which includes permanent and non-permanent, removable and non-removable media. Information storage can be achieved by any method or technology. Information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, read-only compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, tape disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined in this article, computer-readable media does not include transitory computer-readable media (transit media), such as modulated data signals and carrier waves.
[0097] These computer programs can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps of the functions specified in one or more blocks can be implemented by different modules corresponding to different steps.
[0098] Embodiment 7
[0099] Please refer to Figure 2 , Figure 3 An embodiment provides a set of technical solutions involving a method, device and electronic device for determining the initial mineral content in the rock formation process, which is explained below through a case to facilitate further understanding of its technical content.
[0100] The following is a detailed explanation of the deep carbonate reservoir of the Deng 4th Member in Anyue Gas Field, Sichuan Basin, to further illustrate the scheme for determining the initial mineral content in the diagenetic simulation process. The specific steps are as follows:
[0101] (1) Based on the well logging data of the reservoir combined with the sediment source characteristics and lithofacies conditions of the region, the lithofacies type and initial mineral type are preliminarily inferred.
[0102] The sedimentary water of the Dengying Formation in the study area evolved from shallow to deep and then from deep to shallow during the sedimentary period. The evolution of the sedimentary phase generally evolved from shallow water platform to semi-deep water platform and then to shallow water platform. The main reservoir rock types in the fourth section of the Dengying Formation reservoir are algal dolomite, crystalline dolomite, argillaceous dolomite, dolomitic breccia, etc. The mineral components are mainly dolomite, calcite and quartz, and non-siliceous minerals such as pyrite and sphalerite can be seen occasionally. The initial mineral type is speculated to be mainly calcite.
[0103] (2) Determine the current mineral content based on the test data of XRD, XRF, thin section, cathodoluminescence, fluid inclusions, etc. of the reservoir, clarify the characteristics of diagenesis, dissect the diagenetic evolution process, and calculate the initial mineral content based on the chemical reaction mechanism of diagenesis.
[0104] The diagenesis of the carbonate reservoir in the fourth member of Dengjia Formation is mainly compaction-pressure solution, cementation, dissolution, recrystallization, dolomitization, and silicification. The diagenetic stage is the middle-late diagenetic stage, and the diagenetic evolution process is: early mechanical compaction → early seafloor cementation → early dolomitization → diagenetic compaction → early cementation → late hydrothermal dolomitization → hydrothermal mineral formation → organic acid dissolution → late cementation → recrystallization → metasomatism. The Deng 4 Member experienced four phases of fluid charging and three phases of oil and gas charging, which can be summarized as: the first phase of fluid charging (early dolomitization, the formation of microcrystalline dolomite) → the first phase of oil and gas charging (the first phase of asphalt was formed in the Caledonian period, which was basically destroyed by biodegradation) → the second phase of fluid charging (late dolomitization, the formation of a large amount of algae clot dolomite) → the third phase of fluid charging (hydrothermal fluid charging to form saddle dolomite) → the second phase of oil and gas charging (formation of Indosinian movement paleo-oil reservoirs, the beginning of the formation of the second phase of asphalt, filling pores) → the fourth phase of fluid charging (late precipitation increase, stratum uplift, internal fluid secondary balance, large amount of calcite cementation) → the third phase of oil and gas charging (late crude oil cracking to produce natural gas charging and form normal pressure-slightly overpressure reservoirs)
[0105] Shallow atmospheric freshwater leaching continues, and the weakly acidic environment promotes the dissolution of calcite:
[0106] CaCO 3 +H + =Ca 2 ++HCO -3 .
[0107] The early fluid evaporation increased the Mg / Ca ratio of the fluid, and the reservoir was evaporatively dolomitized to form micro-fine-crystalline dolomite.
[0108] During the middle burial period, the reservoir experienced high-Mg fluid, and burial genesis dolomitization occurred. A large amount of calcite was converted into dolomite, which effectively improved the reservoir porosity:
[0109] CaCO3 +Mg 2 ++HCO 3 - =CaMg(CO 3 ) 2 +H + .
[0110] CO generated by decarboxylation of organic acids carried by oil and gas injection 2 First, the reservoir is dissolved, and then the high temperature completely decarboxylates to produce excess CO 2 , providing a "carbon" source for carbonate minerals, producing a large amount of calcite and dolomite cements:
[0111] RCOOH→RH+CO 2
[0112] CO 2 +H 2 O=H + +HCO -3
[0113] CaCO 3 +H + =Ca 2+ +HCO -3
[0114] CaCO 3 +Mg 2+ +HCO 3- =CaMg(CO 3 ) 2 +H +
[0115] Ca 2+ +HCO 3- =CaCO 3 +H +
[0116] The third phase contains SiO 2 The hydrothermal filling formed hydrothermal dolomite and silicified the reservoir to form dolomite-containing siliceous rock and a large amount of cryptocrystalline silicon.
[0117] Late stratum uplift, secondary fluid balance affected by precipitation, late calcite cemented inside the reservoir:
[0118] Ca 2+ +HCO 3- =CaCO 3 +H +
[0119] CaMg(CO 3 ) 2 +H + =CaCO 3 +Mg 2+ +HCO3- .
[0120] The initial mineral calcite content was calculated to be 70% using traditional calculation methods.
[0121] (3) Using numerical simulation methods, we set the paleotemperature, paleopressure, paleofluid and other conditions corresponding to the diagenetic stage, calculated the mineral content in the traditional way as the initial mineral conditions, and set the reaction time on a geological time scale to simulate the first diagenetic stage.
[0122] Based on the thermal history and burial history data, combined with the logging and mud logging data, the basic setting parameters of the numerical simulation are determined.
[0123] Table 1 Formation physical parameters
[0124]
[0125] Table 2 Water chemical composition
[0126]
[0127] Table 3 Rock components and relative contents
[0128]
[0129] Table 4 Simulation time settings for each stage
[0130]
[0131] (4) Using numerical simulation methods, the next diagenetic stage is simulated with the mineral content, fluid water chemical conditions, etc. after the end of the previous diagenetic stage as the initial conditions and repeated until the entire diagenetic evolution process is simulated.
[0132] After the sedimentation-peneosyngenetic seafloor stage reaction, calcite cement was formed, and Mg in the fluid 2+ Replaces Ca in calcite 2 + , magnesium calcite is generated, the calcite content drops to 38.45%, and the iron calcite content rises to 52.16%; with the calcite content of 38.45% and the iron calcite content of 52.16%, the mineral content of the next stage is set, and the early diagenetic period A is simulated using the diagenesis numerical simulation, and so on, until the entire diagenetic evolution process is simulated.
[0133] (5) According to the difference between the mineral content value after diagenetic numerical simulation and the mineral content value calculated by traditional theoretical method, combined with the diagenetic reaction mechanism, the initial mineral content set in the simulation is modified, and the diagenetic evolution simulation is carried out again.
[0134] After simulating the diagenetic evolution process using numerical simulation, the dolomite content was 60.07% and the calcite content was 11.14%. Based on the XRD test, the current dolomite content is 70% and the calcite content is 5%. According to the difference between the simulated mineral content and the current mineral content test, the reason was analyzed, the original calcite content was changed to 75%, and the diagenetic evolution numerical simulation was performed again.
[0135] (6) Based on the reservoir diagenetic evolution process, the initial mineral values are continuously modified and diagenetic numerical simulation is performed until the error is reduced to an acceptable range, and finally the initial mineral content of the diagenetic process is determined.
[0136] After continuous numerical simulation of diagenetic evolution, the initial calcite content was finally determined to be 68.79%. Figure 3 A diagram showing the changes in mineral content for each diagenetic stage.
[0137] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A method for determining the initial mineral content in a rock formation process, characterized in that: include: Based on the sedimentary environment, provenance and lithofacies conditions of the reservoir, the initial mineral type is preliminarily inferred; Conduct petrological testing and analysis on current samples to determine the diagenetic sequence and current mineral types and contents; and, based on the diagenetic sequence and mineral transformation relationship, infer the initial diagenetic mineral types and contents, wherein the inferring of the diagenetic mineral types and contents at the very beginning of the diagenesis and at the beginning of each diagenetic stage; Carry out numerical simulation of diagenesis in the first diagenesis stage based on the set conditions; The result at the end of the previous diagenetic stage is used as the initial condition of the next diagenetic stage, and the diagenetic numerical simulation is repeated until the simulation of all diagenetic stages is completed; The mineral content value after the diagenetic numerical simulation is compared with the mineral content value calculated theoretically by the traditional method. If the error is within an acceptable range, the initial value inferred by the diagenetic numerical simulation is the initial mineral content of the diagenetic process.
2. A method for determining the initial mineral content in the diagenesis process according to claim 1, characterized in that: The petrological testing and analysis of current samples is carried out to determine the diagenetic sequence and the diagenetic evolution process of the reservoir; the determination of the diagenetic evolution process of the reservoir is based on at least one of rock thin section identification, fluid inclusion analysis, isotope testing, and cathode luminescence testing, and combined with burial history and thermal history to determine the diagenetic fluid filling time, porosity evolution process and mineral transformation process of the reservoir at a certain stage.
3. A method for determining the initial mineral content in the diagenesis process according to claim 1 or 2, characterized in that: The petrological test analysis includes one or more of XRD, XRF, thin section, cathode luminescence, and fluid inclusion testing.
4. A method for determining the initial mineral content in the diagenesis process according to claim 1, characterized in that: The conditions set in the diagenetic numerical simulation include: one or more of paleo-temperature, paleo-pressure and paleo-fluid corresponding to the diagenetic stage.
5. A method for determining the initial mineral content in the diagenesis process according to claim 1 or 4, characterized in that: The conditions are set based on the temperature, pressure and fluid type at a certain time during the diagenetic evolution process determined by reservoir thermal history, burial history, well logging, mud logging data, trace elements, carbon isotope or oxygen isotope testing.
6. A method for determining the initial mineral content in the rock formation process according to claim 1, characterized in that: The results at the end of the previous diagenetic stage include one or both of mineral content and fluid water chemical conditions.
7. A method for determining the initial mineral content in the rock formation process according to claim 1, characterized in that: When comparing the mineral content value after the diagenetic numerical simulation with the mineral content value theoretically calculated by the traditional method, if the error exceeds the acceptable range, the initial mineral content in the diagenetic numerical simulation is adjusted, and the simulation is repeated until the simulation result is within the error range. The simulation ends and the initial mineral content inferred by the simulation is obtained.
8. A device for determining the initial mineral content during rock formation, characterized in that: include: The preliminary inference module is used to preliminarily infer the initial mineral type based on the sedimentary environment, provenance and lithofacies conditions of the reservoir; The determination module is used to perform petrological tests and analyses on present-day samples, determine the diagenetic sequence, and determine the present-day mineral types and contents; A reverse inference module is used to reversely infer the initial diagenetic mineral type and content based on the diagenetic sequence and mineral transformation relationship, wherein the diagenetic mineral type and content at the initial stage of diagenesis and the initial stage of each diagenetic stage are reversed; A simulation module, used to perform numerical simulation of the first diagenetic stage based on the set conditions; A repeated simulation module is used to use the result at the end of the previous diagenesis stage as the initial condition of the next diagenesis stage, and repeat the diagenesis numerical simulation until the simulation of all diagenesis stages is completed; and The comparison module is used to compare the mineral content value after the diagenetic numerical simulation with the mineral content value calculated theoretically by the traditional method. If the error is within the acceptable range, the initial value inferred by the diagenetic numerical simulation is the initial mineral content of the diagenetic process.
9. An electronic device, characterized in that: include: Memory; and processor; Wherein, the memory is used to store one or more computer instructions; the one or more computer instructions are executed by the processor to implement the method for determining the initial mineral content in the rock formation process as described in any one of claims 1 to 7.
10. A readable storage medium, characterized in that: The readable storage medium stores computer instructions; wherein, when the computer instructions are executed by a processor, the method for determining the initial mineral content in the rock formation process as described in any one of claims 1 to 7 is implemented.