Medium-and-small-scale fractured reservoir parameter determination method and related device
By identifying and modeling small-scale fractures in reservoirs and using seismic interpretation of ant-like properties as constraints, a three-dimensional geological model of small-scale fracture density is established, generating a discrete fracture network model. This solves the problem of not being able to determine small-scale fractured reservoir parameters in existing technologies, realizes a method for determining fractured reservoir parameters, and provides a new device and method.
Patent Information
- Application Number
- CN202410717104.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-04
- Publication Date
- 2025-12-05
AI Technical Summary
Existing technologies cannot effectively determine parameters of small- to medium-scale fractured reservoirs, especially in oil fields or well areas lacking imaging logging data or core data. Existing technologies cannot effectively establish fracture models, leading to difficulties in geological modeling of fractured reservoirs.
By identifying and modeling small-scale fractures in the reservoir and their parameters, and using seismic interpretation of ant-like properties as constraints, a density-based three-dimensional geological model is established. The DFN (Digital Fracture Network) modeling method is then used to generate discrete fracture models of small-scale fractures, which are then coarsened. This process is repeated in the original text.
This study established a small-to-medium scale fracture density model by obtaining fracture density curves, providing a geological basis for numerical simulation of gas reservoirs, solving the problem of determining parameters of small-to-medium scale fractured reservoirs, and providing new methods and devices.
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Figure CN121069483A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of oil and gas geological exploration, and relates to a method for determining parameters of a medium-small scale fractured reservoir and a related device. BACKGROUND
[0002] Fractures play a crucial role in oil and gas exploration and development. They are not only important seepage channels for gas reservoirs, but also key factors affecting oilfield productivity and reservoir characteristics. Therefore, establishing an accurate and reasonable fracture model is a requirement for oilfield development deployment and numerical simulation research.
[0003] In the vast field of oilfield development, continuous technological progress is the key driving force for the industry's forward development. In particular, at the current stage, the geological modeling technology of sandstone gas reservoirs has matured and has been widely verified and applied in actual oilfield production. This technological breakthrough not only improves the efficiency of oilfield development, but also provides more accurate tools for our in-depth understanding and utilization of underground oil and gas resources. Fractured low-porosity sandstone oil and gas resources have great potential, however, the development of such resources is not easy. In fractured low-porosity sandstone gas reservoirs, due to the complex distribution and poor regularity of fractured reservoirs, the low porosity of the rock, the complex matrix pore structure, and the strong heterogeneity, the conventional sandstone gas reservoir geological modeling method is not suitable for fractured low-porosity sandstone reservoir modeling.
[0004] In fractured low-porosity sandstone gas reservoirs, the oil and gas content and productivity of the reservoir are strongly dependent on fractures. Therefore, the logging identification and evaluation of fractures are critical for the exploration and development of low-porosity sandstone reservoirs. However, the reservoir geological modeling method for fractured oil and gas reservoirs, especially for fractured low-porosity sandstone gas reservoirs, is still in the stage of continuous exploration and research.
[0005] In the process of fractured reservoir modeling, previous studies on interwell fracture prediction are relatively few, and fractured reservoir geological models are established in large and small fracture scales. It is of great significance to study how to determine the parameters of small-scale fractures in fractured carbonate gas reservoirs, and it is also meaningful for oilfields or well areas that have no or very little imaging logging data, or even core data. SUMMARY
[0006] The purpose of the present application is to provide a method for determining parameters of a medium-small scale fractured reservoir and a related device, which solves the problem that the prior art cannot determine the parameters of a medium-small scale fractured reservoir.
[0007] To achieve the above-mentioned purpose, the following technical solutions are adopted in the present application:
[0008] A method for determining parameters of a medium-small scale fractured reservoir, comprising:
[0009] Identify small-scale fractures in the reservoir, determine the fracture parameters of the small-scale fractures;
[0010] Using the fracture parameters of the small-scale fractures, a three-dimensional geological model of small-scale fracture density is established by using the seismic interpretation ant attribute volume as a constraint condition, and under the constraint of the three-dimensional geological model of small-scale fracture density, a small-scale discrete fracture network model is generated by using a DFN fracture network modeling method.
[0011] The small-scale discrete fracture network model is coarsened to obtain the small-scale fracture reservoir parameters.
[0012] Further, the identification object of the small-scale fractures includes an imaging data well and a non-imaging data well.
[0013] Further, the fracture parameter determination method of the imaging data well is:
[0014] The fractures in the reservoir are identified by using core data and imaging logging data to obtain fracture development parameters and determine the fracture parameters of the imaging data well.
[0015] Further, the fracture parameter determination method of the non-imaging data well includes:
[0016] The fractures in the reservoir are identified by using core data to obtain core fracture development parameters;
[0017] The fractures in the reservoir are identified by using imaging logging data to obtain imaging logging fracture development parameters;
[0018] Based on the imaging logging fracture development parameters, a correction multiple of the core fracture development parameters is determined to correct the core fracture development parameters to obtain the fracture parameters of the non-imaging data well.
[0019] Further, the fracture parameter determination method of the small-scale fractures includes:
[0020] The fracture parameters of the imaging data well are compared with logging curves in conventional geophysical logging to find out the change rule of the conventional geophysical logging curves in the fracture development layer section, and a correlation coefficient is determined.
[0021] The fracture parameters of the non-imaging data well are compared with the correlation coefficient to determine the fracture parameters of the small-scale fractures.
[0022] Further, the logging curves include caliper curves, acoustic curves, density curves, and deep and shallow dual lateral resistivity curves.
[0023] Further, the method for establishing the three-dimensional geological model of small-scale fracture density includes:
[0024] The fracture parameters of the small and medium scale fractures are used to generate a fracture accumulation curve, and a fracture density curve is generated according to the fracture accumulation curve;
[0025] The fracture density curve is analyzed by using a numerical simulation method of continuous variables, a fracture density curve of a well point is analyzed by using a variogram, a three-dimensional geological model of small and medium scale fracture density is established by using the seismic interpretation ant attribute volume as a constraint condition.
[0026] A small and medium scale fracture reservoir parameter determination system comprises:
[0027] An identification module is used to identify small and medium scale fractures in a reservoir, and fracture parameters of the small and medium scale fractures are determined;
[0028] A modeling module is used to generate a three-dimensional geological model of small and medium scale fracture density by using the fracture parameters of the small and medium scale fractures and by using the seismic interpretation ant attribute volume as a constraint condition, and a small and medium scale discrete fracture network model is generated by using a DFN fracture network modeling method under the constraint condition of the three-dimensional geological model of small and medium scale fracture density.
[0029] A coarsening module is used to coarsen the small and medium scale discrete fracture network model to obtain small and medium scale fracture reservoir parameters.
[0030] An electronic device comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the method when executing the computer program.
[0031] A computer readable storage medium stores a computer program, and the computer program implements the steps of the method when executed by a processor.
[0032] Compared with the prior art, the present application has the following beneficial effects:
[0033] The present application provides a small and medium scale fracture reservoir parameter determination method, small and medium scale fractures in a reservoir of a well with imaging data and a well without imaging data are identified, fracture parameters of the small and medium scale fractures are determined, a three-dimensional geological model of small and medium scale fracture density is established by using the fracture parameters of the small and medium scale fractures and by using the seismic interpretation ant attribute volume as a constraint condition, a small and medium scale discrete fracture network model is generated by using a DFN fracture network modeling method and is coarsened, and finally small and medium scale fracture reservoir parameters are obtained. BRIEF DESCRIPTION OF DRAWINGS
[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.
[0035] Figure 1 The flow chart of the method for determining the parameters of the small and medium scale fracture reservoir of the present application.
[0036] Figure 2 The seismic data graph of a gas reservoir in Example 1 of the present application in the Klasu gas field.
[0037] Figure 3 The fault and large fracture model graph obtained based on the seismic data of a gas reservoir in Example 1 of the present application in the Klasu gas field.
[0038] Figure 4 The research idea graph for establishing the small and medium scale fracture model of the present application.
[0039] Figure 5 The fracture strike rose graph of a gas reservoir in Example 1 of the present application in the Klasu gas field.
[0040] Figure 6 The fracture density distribution 3D geological model graph of a gas reservoir in Example 1 of the present application in the Klasu gas field.
[0041] Figure 7 The small and medium scale fracture discrete network model graph of a gas reservoir in Example 1 of the present application in the Klasu gas field.
[0042] Figure 8 The structural schematic diagram of the small and medium scale fracture reservoir parameter determination system in the preferred embodiment of the present application.
[0043] Figure 9 The structural schematic diagram of the electronic device in the preferred embodiment of the present application. DETAILED DESCRIPTION
[0044] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the following will combine the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.
[0045] Exemplary embodiments of the present application are described herein below with reference to the accompanying drawings, in which various specific details are set forth to assist in a thorough understanding of these embodiments. It will be apparent, however, to one of ordinary skill in the art that these embodiments can be practiced without some or all of these specific details. In other instances, well known features have not been described in detail so as not to obscure the description of the embodiments.
[0046] It is apparent that the described embodiments are merely some, but not all, of the embodiments of the present application. Based on the embodiments described in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.
[0047] It should be noted that the terminal involved in the embodiments of the present application can include, but is not limited to, a mobile phone, a personal digital assistant (PDA), a wireless handheld device, a tablet computer, a personal computer (PC), an MP3 player, an MP4 player, a wearable device (for example, smart glasses, a smart watch, a smart bracelet, etc.), a smart home device, and the like.
[0048] In addition, the term "and / or" in this paper is only a description of the association relationship between the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents an "or" relationship between the associated objects before and after it.
[0049] The present application will be described in further detail below with reference to the accompanying drawings:
[0050] Referring to Figure 1 The present application provides a method for determining parameters of a small and medium scale fracture reservoir, comprising the following steps:
[0051] Step 1: Identify the small and medium scale fractures in the reservoir, and determine the fracture parameters of the small and medium scale fractures.
[0052] (1) For wells with imaging data: use core data to identify reservoir fractures and determine core fracture development parameters, including: fracture distribution density, orientation, length, and opening degree, etc.
[0053] Use imaging logging data to identify reservoir fractures and determine imaging logging fracture development parameters, including: fracture distribution density, orientation, length, and opening degree, etc.
[0054] According to the core fracture development parameters and the imaging logging fracture development parameters, the fracture parameters of the well with imaging data are determined.
[0055] (2) For the well without imaging data: the core data is used to identify the reservoir fracture, and the core fracture development parameters are determined, including: fracture distribution density, orientation, length and opening degree, etc.
[0056] The imaging logging data is used to identify the reservoir fracture, and the imaging logging fracture development parameters are determined, including: fracture distribution density, orientation, length and opening degree, etc.
[0057] The core fracture development parameters and the imaging logging fracture development parameters obtained from the core and the imaging logging data are compared, and the correction multiple between the two is determined based on the imaging logging, the core fracture development parameters are corrected, and the fracture parameters of the well without imaging logging data are obtained, including: fracture distribution density, orientation, length and opening degree, etc.
[0058] (3) The fracture parameters of the small and medium scale fractures: the fracture parameters of the well with imaging data are compared with the logging curves in the conventional geophysical logging, the logging curves include caliper curve, acoustic curve, density curve and deep and shallow dual lateral resistivity curve, the change rule of the conventional geophysical logging curve in the fracture development layer is found out, and the correlation coefficient is determined.
[0059] The fracture parameters of the well without imaging data are compared with the correlation coefficient to determine the final fracture parameters of the small and medium scale fractures.
[0060] (4) For the well without core data: the correlation coefficient can be directly used to determine the fracture parameters of the well without imaging logging data.
[0061] Step two: the fracture parameters of the small and medium scale fractures are used to establish a three-dimensional geological model of small and medium scale fracture density, with the seismic interpretation ant attribute body as the constraint condition.
[0062] The fracture parameters of the small and medium scale fractures are used to generate a fracture cumulative curve (cumulative), and a fracture intensity curve (intensity) is generated according to the fracture cumulative curve.
[0063] The fracture intensity curve is used to analyze the variogram of the fracture intensity curve at the well point by using the numerical simulation method of continuous variable, and a three-dimensional geological model of fracture density is established with the seismic interpretation ant attribute body as the constraint condition.
[0064] Step three: under the constraint of the three-dimensional geological model of small and medium scale fracture density, a small and medium scale discrete fracture network model is generated by using the DFN fracture network modeling method.
[0065] Using the DFN fracture network modeling method, based on the statistical analysis results of fracture parameters of small and medium-scale fractures, the geometric morphology and orientation parameters of small and medium-scale fractures are set. Under the constraint of the three-dimensional geological model of fracture density, fracture patches are generated by random simulation, and finally, a small and medium-scale discrete fracture network model is randomly generated.
[0066] Step 4: Coarsen the small- and medium-scale discrete fracture network model to obtain the small- and medium-scale fracture reservoir parameters.
[0067] The generated small-to-medium scale discrete fracture network model is coarsened. The coarsening process sets the fracture parameters of the small-to-medium scale fractures, including fracture length, aperture, and fracture permeability, in order to determine the final small-to-medium scale fracture reservoir parameters.
[0068] The present invention will be further described in detail below with reference to specific embodiments:
[0069] Example 1:
[0070] Taking a gas reservoir in the Kelasu gas field as an example, based on seismic data of the gas reservoir, automatic ant tracking technology was used to identify faults and large-scale fractures, such as... Figure 2 As shown, fractures are marked with solid lines, and large cracks are marked with dashed lines, such as... Figure 3 As shown, a specific model is used to characterize the cracks. Based on the same method, data on small- to medium-scale cracks can be obtained. A detailed research approach diagram is shown below. Figure 4 As shown.
[0071] Based on core and conventional logging information, fracture morphology and fracture development intensity can be identified, including data such as fracture orientation, density, and aperture. The fracture orientation rose diagram is shown below. Figure 5 As shown, equivalent fracture parameters are obtained based on imaging logging data, corrected with core data, and thus the final reservoir fracture data are obtained. Using neural network and other data methods, a correlation chart is established between imaging logging, core data, and conventional geophysical logging, providing the possibility of identifying fracture parameters using conventional geophysical logging for wells without core data, with poor imaging logging data, or without imaging logging data.
[0072] Based on the above data, a three-dimensional geological model of fracture density distribution can be obtained, such as... Figure 6 As shown, and combined with a lithofacies model, a discrete fracture network model at a small to medium scale is established, such as... Figure 7 As shown in the figure, reservoir parameters and fracture parameters are determined based on the generated discrete fracture network model, which improves the basic data for characterizing water intrusion channels in gas reservoirs.
[0073] Example 2:
[0074] Embodiment 2 provided by this invention is an embodiment of the system for determining small-to-medium scale fractured reservoir parameters provided by this invention, such as...Figure 8 As shown, the embodiment of the system comprises an identification module, a modeling module and a coarsening module.
[0075] The identification module is configured to identify small-scale fractures in the reservoir and determine fracture parameters of the small-scale fractures.
[0076] The modeling module is configured to establish a small-scale fracture density three-dimensional geological model by using the fracture parameters of the small-scale fractures and taking the seismic interpretation ant property volume as a constraint condition, and generate a small-scale discrete fracture network model by using a DFN fracture network modeling method under the constraint of the small-scale fracture density three-dimensional geological model.
[0077] The coarsening module is configured to coarsen the small-scale discrete fracture network model to obtain small-scale fracture reservoir parameters.
[0078] It can be understood that the small-scale fracture reservoir parameter determination system provided by the present application corresponds to the small-scale fracture reservoir parameter determination method provided by the above-mentioned embodiments, and the related technical features of the small-scale fracture reservoir parameter determination system can refer to the related technical features of the small-scale fracture reservoir parameter determination method, and specifically include the following steps:
[0079] The identification module is configured to identify small-scale fractures in the reservoir and determine fracture parameters of the small-scale fractures.
[0080] The modeling module is configured to establish a small-scale fracture density three-dimensional geological model by using the fracture parameters of the small-scale fractures and taking the seismic interpretation ant property volume as a constraint condition, and generate a small-scale discrete fracture network model by using a DFN fracture network modeling method under the constraint of the small-scale fracture density three-dimensional geological model.
[0081] The coarsening module is configured to coarsen the small-scale discrete fracture network model to obtain small-scale fracture reservoir parameters.
[0082] Embodiment 3:
[0083] The present embodiment provides an electronic device, such as Figure 9 As shown, it comprises a memory, a processor and a computer program stored in the memory and executable on the processor, and the processor executes the steps of the small-scale fracture reservoir parameter determination method.
[0084] The small-scale fracture reservoir parameter determination method comprises the following steps:
[0085] The small-scale fracture reservoir parameter determination method comprises the following steps:
[0086] The fracture parameters of the small and medium scale fractures are used to establish a small and medium scale fracture density three-dimensional geological model under the constraint of the seismic interpretation ant attribute volume, and a small and medium scale discrete fracture network model is generated by using a DFN fracture network modeling method under the constraint of the small and medium scale fracture density three-dimensional geological model.
[0087] The small and medium scale discrete fracture network model is coarsened to obtain small and medium scale fracture reservoir parameters.
[0088] Embodiment 4:
[0089] The embodiment provides a computer readable storage medium, and the computer readable storage medium stores a computer program.
[0090] The small and medium scale fracture reservoir parameter determination method comprises the following steps:
[0091] The small and medium scale fractures in the reservoir are identified to determine the fracture parameters of the small and medium scale fractures;
[0092] The fracture parameters of the small and medium scale fractures are used to establish a small and medium scale fracture density three-dimensional geological model under the constraint of the seismic interpretation ant attribute volume, and a small and medium scale discrete fracture network model is generated by using a DFN fracture network modeling method under the constraint of the small and medium scale fracture density three-dimensional geological model.
[0093] The small and medium scale discrete fracture network model is coarsened to obtain small and medium scale fracture reservoir parameters.
[0094] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can adopt a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can adopt a computer program product in the form of being implemented on one or more computer usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program codes.
[0095] The present application is described with reference to flowcharts and / or block diagrams of the method, device (system), and computer program product according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to produce a machine, so that the instructions executed by the computer or other programmable data processing devices produce a device for implementing the functions described in the flowcharts and / or block diagrams. Figure 1apparatuses that implement the functions specified in the flowchart or flowcharts and / or blocks. Figure 1
[0096] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the flowchart or flowcharts and / or blocks. Figure 1 Figure 1
[0097] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the flowchart or flowcharts and / or blocks. Figure 1 Figure 1
[0098] Finally, it should be noted that the above-mentioned embodiments are merely intended to illustrate the technical solutions of the present application, rather than limit the same. Even though the present application has been described in detail with reference to the above-mentioned embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and any modification or replacement without departing from the spirit and scope of the present application should be included in the protection scope of the claims of the present application.
Claims
1. A method for determining parameters of small- to medium-scale fractured reservoirs, characterized in that, The method comprises the following steps: identifying small-scale fractures in the reservoir and determining fracture parameters of the small-scale fractures; using the fracture parameters of the small-scale fractures to establish a three-dimensional geological model of small-scale fracture density under the constraint of a seismic interpretation ant attribute volume, and using a DFN fracture network modeling method to generate a small-scale discrete fracture network model under the constraint of the three-dimensional geological model of small-scale fracture density; coarsening the small-scale discrete fracture network model to obtain small-scale fracture reservoir parameters.
2. The method of claim 1, wherein, The identification object of the small-scale fractures comprises imaging data wells and non-imaging data wells.
3. The method of claim 2, wherein, The fracture parameter determination method for the imaging data wells comprises the following steps: identifying reservoir fractures using core data and imaging logging data to obtain fracture development parameters and determine fracture parameters of the imaging data wells.
4. The method of claim 2, wherein, The fracture parameter determination method for the non-imaging data wells comprises the following steps: identifying reservoir fractures using core data to obtain core fracture development parameters; identifying reservoir fractures using imaging logging data to obtain imaging logging fracture development parameters; based on the imaging logging fracture development parameters, determining a correction multiple of the core fracture development parameters, correcting the core fracture development parameters, and obtaining fracture parameters of the non-imaging data wells.
5. The method of claim 1, wherein, The fracture parameter determination method for the small-scale fractures comprises the following steps: comparing the fracture parameters of the imaging data wells with logging curves in conventional geophysical logging to find out the change rule of the conventional geophysical logging curves in fracture development intervals and determine a correlation coefficient; comparing the fracture parameters of the non-imaging data wells with the correlation coefficient to determine fracture parameters of the small-scale fractures.
6. The method of claim 5, wherein, The logging curves comprise caliper curves, sonic curves, density curves and deep / lateral resistivity curves.
7. The method of claim 1, wherein, The method for establishing the three-dimensional geological model of small-scale fracture density comprises the following steps: generating a fracture cumulative curve using the fracture parameters of the small-scale fractures, and generating a fracture density curve according to the fracture cumulative curve; performing variogram analysis on the fracture density curve of a well point using a continuous variable numerical simulation method, and establishing a three-dimensional geological model of small-scale fracture density under the constraint of a seismic interpretation ant attribute volume.
8. A small-to-mid scale fractured reservoir parameter determination system, characterized by, The method comprises the following steps: an identification module configured to identify small-scale fractures in the reservoir and determine fracture parameters of the small-scale fractures; a modeling module configured to use the fracture parameters of the small-scale fractures to establish a three-dimensional geological model of small-scale fracture density under the constraint of a seismic interpretation ant attribute volume, and generate a small-scale discrete fracture network model under the constraint of the three-dimensional geological model of small-scale fracture density using a DFN fracture network modeling method; a coarsening module configured to coarsen the small-scale discrete fracture network model to obtain small-scale fracture reservoir parameters.
9. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the computer program to realize the steps of the method in any one of claims 1-7.
10. A computer-readable storage medium storing a computer program, the computer program comprising instructions that, when executed by a computer, cause the computer to perform the method of any one of claims 1 to 9. The computer program is executed by the processor to realize the steps of the method in any one of claims 1-7.