Method and device for determining dessert section of giant thick lignite reservoir and electronic equipment
By combining the logging electrical characteristics, acoustic time difference and resistivity data, the coal rock type and pore structure categories of huge thick lignite coal seams are identified, which solves the problem that it is difficult to identify dessert sections in the existing technology, and achieves a technological breakthrough in coalbed methane mining in low-coal-stage areas.
Patent Information
- Application Number
- CN202311278390.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-09-28
- Publication Date
- 2025-03-28
AI Technical Summary
The prior art is difficult to accurately identify the dessert sections of huge thick lignite coal seams, especially in low-coal stairs, where logging classification standards for lignite coal rock types are lacking.
By using the mapping relationship between logging electrical characteristics and coal rock types, combining sound wave time difference and resistivity data, the established pore structure type identification diagram is used to determine the coal rock type and pore structure category of the coal reservoir, so as to determine whether it is a dessert section.
The accurate and effective identification of the dessert sections of the huge thick lignite coal seam has been achieved, the difficulties in coalbed methane mining technology in low-coal-level areas have been solved, and the efficiency of exploration and development has been improved.
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Figure CN119719835A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of coalbed methane mining, and in particular to a method, device and electronic equipment for determining a sweet spot section of a thick lignite coal reservoir. Background Art
[0002] In recent years, my country's coalbed methane industry has developed rapidly, and coalbed methane has entered the stage of large-scale development. At present, coalbed methane development is mainly concentrated in high-rank coal areas, and most blocks have been put into development. To continuously expand production, the focus of exploration and development must be expanded to medium and low-rank coal areas. my country has a rich low-rank coalbed methane resource base, but my country is still in the initial stage of technology in the exploitation of low-rank coalbed methane.
[0003] For extremely thick low-rank lignite coal bodies, multiple coal rock types and pore structure types appear alternately in the vertical direction, which is highly heterogeneous. Different coal rock types have different fracturing properties, and the pore structure affects gas desorption, diffusion and seepage. Accurately identifying the sweet spots of high-quality coal rock types and pore structures is the key to breakthroughs in the exploration and development of such coal reservoirs. In related technologies, logging technology can be used to identify only high-rank coal rock types, but logging curves cannot be used to accurately and effectively identify the sweet spots of extremely thick lignite coal seams. The coal rock types of low-rank lignite are different from those of high-rank coal. Currently, there is no logging classification standard for lignite coal rock types, so there is still a lack of identification solutions for the sweet spots of extremely thick lignite coal seams with low coal ranks.
[0004] Therefore, how to accurately and effectively determine the sweet spot section of extremely thick lignite seams is a technical problem that needs to be solved urgently. Summary of the invention
[0005] The embodiments of the present application provide a method, device and electronic equipment for determining the sweet spot segment of a thick lignite coal reservoir, which are used to accurately and effectively determine the sweet spot segment of a thick lignite coal seam.
[0006] One of the embodiments of the present application provides a method for determining a sweet spot segment of a huge thick lignite coal reservoir, the method comprising: determining the coal rock type of the huge thick lignite coal reservoir to be identified based on the well logging electrical characteristics of the huge thick lignite coal reservoir to be identified and utilizing an established mapping relationship between the coal rock type of the huge thick lignite coal reservoir and the well logging electrical characteristics; determining the category of the pore structure of the huge thick lignite coal reservoir to be identified based on the sonic time difference and resistivity of the huge thick lignite coal reservoir to be identified and utilizing an established pore structure type identification plate of the huge thick lignite coal reservoir; determining whether the huge thick lignite coal reservoir to be identified is a sweet spot segment based on the coal rock type and pore structure category of the huge thick lignite coal reservoir to be identified.
[0007] In some embodiments, a mapping relationship between the coal rock type and the logging electrical characteristics of the giant thick lignite coal reservoir is established in the following manner: for the parameter data of each giant thick lignite coal reservoir, the coal rock type of the giant thick lignite coal reservoir is determined by coring observation; wherein, the parameter data of the giant thick lignite coal reservoir is collected from coring wells, special logging wells or unknown wells; for the logging parameters of each giant thick lignite coal reservoir, the logging electrical characteristics of the giant thick lignite coal reservoir are determined by core homing; wherein, the logging parameters are sensitive to the coal rock type of the giant thick lignite coal reservoir, and the logging parameters include: natural gamma, compensated density, and compensated neutron; according to the logging electrical characteristics and coal rock type of each giant thick lignite coal reservoir, a mapping relationship between the giant thick lignite coal reservoir type and the logging electrical characteristics is obtained.
[0008] In some embodiments, the pore structure type identification map is obtained by: classifying the pore structures of the various extremely thick lignite coal reservoirs according to the nuclear magnetic resonance interpretation results of the pore structures of the various extremely thick lignite coal reservoirs to obtain multiple categories of pore structures; establishing an acoustic time difference-resistivity cross-plot on a plane rectangular coordinate system; obtaining multiple coordinate points on the acoustic time difference-resistivity cross-plot based on the acoustic time difference data and resistivity data of each of the extremely thick lignite coal reservoirs; and obtaining the pore structure type identification map according to the categories of the pore structures corresponding to the multiple coordinate points.
[0009] In some embodiments, determining whether the to-be-identified huge thick lignite coal reservoir is a sweet spot segment based on the coal rock type and pore structure category of the to-be-identified huge thick lignite coal reservoir comprises: in response to the coal rock type of the to-be-identified huge thick lignite coal reservoir being high-quality coal rock, and the category of the pore structure being a first category, determining that the to-be-identified huge thick lignite coal reservoir is a sweet spot segment; wherein the pore structure of the first category is the highest quality pore structure.
[0010] One of the embodiments of the present application provides a device for determining a sweet spot segment of a huge thick lignite coal reservoir, the device comprising: a first determination module, for determining the coal rock type of the huge thick lignite coal reservoir to be identified according to the well logging electrical characteristics of the huge thick lignite coal reservoir to be identified, using an established mapping relationship between the coal rock type of the huge thick lignite coal reservoir and the well logging electrical characteristics; a second determination module, for determining the category of the pore structure of the huge thick lignite coal reservoir to be identified according to the sonic time difference and resistivity of the huge thick lignite coal reservoir to be identified, using an established pore structure type identification plate of the huge thick lignite coal reservoir; a third determination module, for determining whether the huge thick lignite coal reservoir to be identified is a sweet spot segment according to the coal rock type and pore structure category of the huge thick lignite coal reservoir to be identified.
[0011] An embodiment of the present application provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the method described above when running the program.
[0012] An embodiment of the present application provides a storage medium for storing a computer-readable program. When the computer-readable program is executed, the method described above is executed.
[0013] The above technical solution provided by the embodiment of the present application has at least the following advantages compared with the prior art:
[0014] In the embodiment provided by the present application, the coal rock type of the huge thick lignite coal reservoir to be identified is determined based on the well logging electrical characteristics of the huge thick lignite coal reservoir to be identified, using the established mapping relationship between the coal rock type of the huge thick lignite coal reservoir and the well logging electrical characteristics; the category of the pore structure of the huge thick lignite coal reservoir to be identified is determined based on the acoustic wave time difference and resistivity of the huge thick lignite coal reservoir to be identified, using the established pore structure type identification plate of the huge thick lignite coal reservoir; and whether the huge thick lignite coal reservoir to be identified is a sweet spot is determined based on the coal rock type and pore structure category of the huge thick lignite coal reservoir to be identified. Thus, the sweet spot of the huge thick lignite coal seam can be accurately and effectively determined. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The present application will be further described in the form of exemplary embodiments, which will be described in detail by way of the accompanying drawings. These embodiments are not restrictive, and in these embodiments, the same number represents the same structure, wherein:
[0016] Figure 1 is an exemplary flow chart of a method for determining a sweet spot section of a thick lignite coal reservoir according to some embodiments of the present application;
[0017] Figure 2A is an exemplary schematic diagram of cores of different coal rock types of a thick lignite coal reservoir according to some embodiments of the present application;
[0018] Figure 2B is an exemplary schematic diagram of cores of different coal rock types of another huge thick lignite coal reservoir according to some embodiments of the present application;
[0019] Figure 2C is an exemplary schematic diagram of a method for selecting coal rock types for a thick lignite coal reservoir according to some embodiments of the present application;
[0020] Figure 2D is an exemplary schematic diagram of another method for selecting coal rock types for a thick lignite coal reservoir according to some embodiments of the present application;
[0021] Figure 3Ais an exemplary schematic diagram of classifying pore structures using nuclear magnetic logging data according to some embodiments of the present application;
[0022] Figure 3B is another exemplary schematic diagram of classifying pore structures using nuclear magnetic logging data according to some embodiments of the present application;
[0023] Figure 4A is an exemplary schematic diagram of a pore structure type identification plate according to some embodiments of the present application;
[0024] Figure 4B is an exemplary schematic diagram of another pore structure type identification plate shown in some embodiments of the present application;
[0025] Figure 5A is an exemplary schematic diagram of identifying sweet spots according to high-quality coal rock types and pore structures according to some embodiments of the present application;
[0026] Figure 5B is another exemplary schematic diagram of identifying sweet spots according to high-quality coal rock types and pore structures according to some embodiments of the present application;
[0027] Figure 6 is an exemplary schematic diagram of a device for determining a sweet spot section of a thick lignite coal reservoir according to some embodiments of the present application;
[0028] Figure 7 It is a schematic diagram of an exemplary structure of an electronic device according to some embodiments of the present application. DETAILED DESCRIPTION
[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.
[0030] It should be understood that the "system", "device", "unit" and / or "module" used herein are a method for distinguishing different components, elements, parts, portions or assemblies at different levels. However, if other words can achieve the same purpose, the words can be replaced by other expressions.
[0031] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "comprises" and "includes" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.
[0032] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, the various steps may be processed in reverse order or simultaneously. At the same time, other operations may also be added to these processes, or one or more operations may be removed from these processes.
[0033] For ease of understanding, the technical solution of the present application is introduced below in conjunction with the accompanying drawings and embodiments.
[0034] Figure 1 FIG. 1 is an exemplary flow chart of a method for determining a sweet spot in a thick lignite coal reservoir according to some embodiments of the present application. Figure 1 As shown, the method for determining the sweet spot section of a thick lignite coal reservoir includes the following steps:
[0035] Step S110, according to the logging electrical characteristics of the to-be-identified extremely thick lignite coal reservoir, using the established mapping relationship between the coal rock type of the to-be-identified extremely thick lignite coal reservoir and the logging electrical characteristics, the coal rock type of the to-be-identified extremely thick lignite coal reservoir is determined.
[0036] The logging electrical characteristics can be the range of logging parameters that are sensitive to the coal rock type of the thick lignite coal reservoir, such as the range of natural gamma data (e.g., less than 30), the range of compensated density data (e.g., heavy rain 1.3), the range of compensated neutron data (e.g., less than 53), etc.
[0037] The macroscopic coal rock types of the thick lignite coal reservoir include woody coal, silky coal, clastic coal and mineralized coal. In the specific implementation process, the lignite coal rock type classification scheme issued by the International Coal Petrology Commission (ICCP) and the lignite macroscopic coal rock type classification of domestic scholars can be referred to. Through core sampling observation, the different coal rock types (such as Figure 2A and Figure 2BAs shown). The wood content in woody coal is >30%, with low density, strong brittleness, dark color, dull asphalt luster, and flat or shell-shaped fracture. Woody coal has low mechanical strength, and endogenous cracks and exogenous joints are very developed. The wood content in detrital coal is <30%, brown-black, and composed of a humus matrix of fine-grained debris. Detrital coal tends to be denser as the amount of embedded wood decreases and the ash content increases. The silky coal has a charcoal content of >30%, is gray-black, has well-developed stratification, a fibrous structure, is loose and porous, and is brittle. Various minerals can be seen in mineralized coal as coal-mineral symbioses formed by the above-mentioned rock types, and the mineral content visible to the naked eye is greater than 10%.
[0038] In some embodiments, factors such as fracture development, modifiability, proportion, gas content, etc. can be comprehensively considered to optimize the coal rock type.
[0039] In the specific implementation process, the fracture development, reformability, proportion, and gas content of different coal and rock types can be obtained through core observation, triaxial mechanical test, and gas content test (such as Figure 2C and 2D As shown in the figure). Mineralized coal has no cracks after fracturing, only deformation, and is not suitable for fracturing transformation; silky coal accounts for a small proportion in the coal seam; woody coal and clastic coal both produce cracks after fracturing and have a certain gas content and proportion, while woody coal has developed internal cracks and better fracturing transformation effect, so woody coal is the best coal rock type.
[0040] As an example only, the natural gamma, compensated density, and compensated neutron of the huge and thick lignite coal reservoir to be identified can be obtained, and the mapping relationship between the coal rock type and the logging electrical characteristics of the huge and thick lignite coal reservoir as shown in the following table (Table 1) can be used to determine whether the coal rock type of the huge and thick lignite coal reservoir to be identified is woody coal, silky coal, clastic coal, or mineralized coal.
[0041]
[0042] Table 1
[0043] In the specific implementation process, the mapping relationship between the coal rock type and the well logging electrical characteristics of the thick lignite coal reservoir can be established in the following ways:
[0044] For the parameter data of each super-thick lignite coal reservoir, the coal rock type of the super-thick lignite coal reservoir is determined through coring observation; wherein, the parameter data of the super-thick lignite coal reservoir is collected from coring wells, special logging wells or unknown wells; for the logging parameters of each of the super-thick lignite coal reservoirs, the logging electrical characteristics of the super-thick lignite coal reservoir are determined through core homing; wherein, the logging parameters are sensitive to the coal rock type of the super-thick lignite coal reservoir, and the logging parameters include: natural gamma, compensated density, and compensated neutron; according to the logging electrical characteristics and coal rock type of each super-thick lignite coal reservoir, the mapping relationship between the super-thick lignite coal reservoir type and the logging electrical characteristics is obtained as shown in Table 1.
[0045] Step S120, determining the type of the pore structure of the to-be-identified huge thick lignite coal reservoir according to the acoustic wave time difference and resistivity of the to-be-identified huge thick lignite coal reservoir and using the established pore structure type identification chart of the to-be-identified huge thick lignite coal reservoir.
[0046] According to the literature survey, large and medium pores and other flow pores are well developed, and there are transition pores between the flow pores and the adsorption pores. The pore structure with good connectivity is conducive to the desorption, diffusion and seepage of coalbed methane. The pore structure of the coal reservoir is evaluated by the results of nuclear magnetic interpretation. Therefore, the pore structure is divided into the first category, the second category, the third category and the fourth category from good to bad (corresponding to Figure 3A and Figure 3B Class I, Class II, Class III, and Class IV as shown).
[0047] In the specific implementation process, the pore structure type identification chart is as follows Figure 4A and Figure 4B As shown, a coordinate point on the pore structure type identification chart can be determined based on the acoustic wave time difference and resistivity of the huge and thick lignite coal reservoir to be identified, and the pore structure of the huge and thick lignite coal reservoir to be identified can be determined based on the position of the coordinate point. For example, if the coordinate point is located in the interval where the Class I mark is located, then the pore structure category of the huge and thick lignite coal reservoir to be identified is Class I.
[0048] In the specific implementation process, the pore structure type identification chart of the thick lignite coal reservoir can be established in the following ways:
[0049] In some embodiments, the pore structures of various extremely thick lignite coal reservoirs can be classified according to the NMR interpretation results of the pore structures of various extremely thick lignite coal reservoirs (such as the pore type and T2 spectrum peak correspondence table shown in Table 2) to obtain multiple categories of pore structures; wherein the multiple categories of pore structures include: Category 1, Category 2, Category 3 and Category 4.
[0050]
[0051] In the specific implementation process, conventional logging parameters that are sensitive to the pore structure of the thick lignite coal reservoir can be selected to establish a pore structure type identification chart for the thick lignite coal reservoir.
[0052] Acoustic time difference and resistivity are most sensitive to pore structure response. In some embodiments, an acoustic time difference-resistivity intersection diagram can be established on a plane rectangular coordinate system. For example, the acoustic time difference can be selected as the horizontal coordinate and the resistivity can be selected as the vertical coordinate, or the acoustic time difference can be selected as the vertical coordinate and the resistivity can be selected as the horizontal coordinate.
[0053] In some embodiments, multiple coordinate points on the acoustic time difference-resistivity cross-plot can be obtained based on the acoustic time difference data and resistivity data of each thick lignite coal reservoir; and the types of pore structures corresponding to the multiple coordinate points can be obtained as follows: Figure 4A and Figure 4B Pore structure type identification plate shown.
[0054] According to the acoustic time difference data and resistivity data of each thick lignite coal reservoir, the data points on the acoustic time difference-resistivity cross-plot are drawn, and the distribution intervals of pore structures of types I (corresponding to the first category), II (corresponding to the second category), III (corresponding to the third category), and IV (corresponding to the fourth category) are divided according to the distribution law of the data points (e.g. Figure 4A and 4B shown).
[0055] Class I: high acoustic time difference and high resistivity;
[0056] Class II: The acoustic time difference is slightly lower and the resistivity is higher;
[0057] Class III: high acoustic time difference and low resistivity;
[0058] Class IV: low acoustic time difference and high resistivity (dense).
[0059] Step S130, determining whether the to-be-identified extremely thick lignite coal reservoir is a sweet spot according to the coal rock type and pore structure category of the to-be-identified extremely thick lignite coal reservoir.
[0060] In the specific implementation process, high-quality coal rock type and high-quality pore structure can be used as identification conditions for identifying the thick lignite coal reservoir as a sweet spot.
[0061] In some embodiments, when the coal rock type of the to-be-identified thick lignite coal reservoir is high-quality coal rock and the category of the pore structure is the first category, the to-be-identified thick lignite coal reservoir is determined to be a sweet spot. Figure 5A and Figure 5BAs shown, according to the well logging curve of Well B, the coal rock type and pore structure are identified. The 440-473m section is a well-developed woody coal with the best quality pore structure of the first category, and this section is determined to be a sweet spot.
[0062] In the implementation provided by the present application, the coal rock type of the giant thick lignite coal reservoir to be identified is determined based on the well logging electrical characteristics of the giant thick lignite coal reservoir to be identified, using the established mapping relationship between the coal rock type of the giant thick lignite coal reservoir and the well logging electrical characteristics; the category of the pore structure of the giant thick lignite coal reservoir to be identified is determined based on the acoustic wave time difference and resistivity of the giant thick lignite coal reservoir to be identified, using the established pore structure type identification plate of the giant thick lignite coal reservoir; and whether the giant thick lignite coal reservoir to be identified is a sweet spot segment is determined based on the coal rock type and pore structure category of the giant thick lignite coal reservoir to be identified. Therefore, it is possible to accurately determine whether the giant thick lignite coal reservoir is a sweet spot segment based only on the conventional well logging parameters of the giant thick lignite coal reservoir.
[0063] Figure 6 It is an exemplary schematic diagram of a device for determining a sweet spot section of a thick lignite coal reservoir according to some embodiments of the present application.
[0064] like Figure 6 As shown, the device for determining the sweet spot section of a thick lignite coal reservoir includes: a first determination module 610 , a second determination module 620 , and a third determination module 630 .
[0065] The first determination module 610 is used to determine the coal rock type of the to-be-identified huge thick lignite coal reservoir according to the well logging electrical characteristics of the to-be-identified huge thick lignite coal reservoir and by using the established mapping relationship between the coal rock type of the to-be-identified huge thick lignite coal reservoir and the well logging electrical characteristics.
[0066] The second determination module 620 is used to determine the type of pore structure of the to-be-identified huge thick lignite coal reservoir according to the acoustic wave time difference and resistivity of the to-be-identified huge thick lignite coal reservoir and using the established pore structure type identification plate of the to-be-identified huge thick lignite coal reservoir.
[0067] The third determination module 630 determines whether the to-be-identified huge thick lignite coal reservoir is a sweet spot according to the coal rock type and pore structure category of the to-be-identified huge thick lignite coal reservoir.
[0068] In some embodiments, a mapping relationship between the coal rock type and the logging electrical characteristics of the giant thick lignite coal reservoir is established in the following manner: for the parameter data of each giant thick lignite coal reservoir, the coal rock type of the giant thick lignite coal reservoir is determined by coring observation; wherein, the parameter data of the giant thick lignite coal reservoir is collected from coring wells, special logging wells or unknown wells; for the logging parameters of each giant thick lignite coal reservoir, the logging electrical characteristics of the giant thick lignite coal reservoir are determined by core homing; wherein, the logging parameters are sensitive to the coal rock type of the giant thick lignite coal reservoir, and the logging parameters include: natural gamma, compensated density, and compensated neutron; according to the logging electrical characteristics and coal rock type of each giant thick lignite coal reservoir, a mapping relationship between the giant thick lignite coal reservoir type and the logging electrical characteristics is obtained.
[0069] In some embodiments, the pore structure type identification map is obtained by: classifying the pore structures of the various extremely thick lignite coal reservoirs according to the nuclear magnetic resonance interpretation results of the pore structures of the various extremely thick lignite coal reservoirs to obtain multiple categories of pore structures; establishing an acoustic time difference-resistivity cross-plot on a plane rectangular coordinate system; obtaining multiple coordinate points on the acoustic time difference-resistivity cross-plot based on the acoustic time difference data and resistivity data of each of the extremely thick lignite coal reservoirs; and obtaining the pore structure type identification map according to the categories of the pore structures corresponding to the multiple coordinate points.
[0070] In some embodiments, determining whether the to-be-identified huge thick lignite coal reservoir is a sweet spot segment based on the coal rock type and pore structure category of the to-be-identified huge thick lignite coal reservoir comprises: in response to the coal rock type of the to-be-identified huge thick lignite coal reservoir being high-quality coal rock, and the category of the pore structure being a first category, determining that the to-be-identified huge thick lignite coal reservoir is a sweet spot segment; wherein the pore structure of the first category is the highest quality pore structure.
[0071] In the above-mentioned embodiment of the device for determining the sweet spot section of a thick lignite coal reservoir, the specific processing of each module and the technical effects it brings can be referred to the relevant descriptions in the corresponding method embodiments, and will not be repeated here.
[0072] Figure 7 It is a schematic diagram of an exemplary structure of an electronic device according to some embodiments of the present application.
[0073] like Figure 7As shown, the electronic device includes: at least one processor 701, at least one communication interface 702, at least one memory 703 and at least one communication bus 704; optionally, the communication interface 702 may be an interface of a communication module, such as an interface of a GSM module; the processor 701 may be a processor CPU, or an application-specific integrated circuit ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present invention. The memory 703 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk storage. The memory 703 stores a program, and the processor 701 calls the program stored in the memory 703 to execute part or all of the above-mentioned method embodiments.
[0074] The present application relates to a storage medium for storing a computer-readable program. When the computer-readable program is executed, part or all of the above-mentioned method embodiments are executed.
[0075] Alternatively, the storage medium may be a non-transitory computer-readable storage medium, for example, the non-transitory computer-readable storage medium may be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, and the like.
[0076] Based on the same inventive concept, an embodiment of the present application further provides a computer program product, including a computer program, which implements part or all of the above-mentioned method embodiments when executed by a processor.
[0077] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only for example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.
[0078] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or multiple times in different positions in the present application does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.
[0079] In addition, unless explicitly stated in the claims, the order of the processing elements and sequences described in this application, the use of alphanumeric characters, or the use of other names are not intended to limit the order of the processes and methods of this application. Although the above disclosure discusses some invention embodiments that are currently considered useful through various examples, it should be understood that such details are only for illustrative purposes, and the attached claims are not limited to the disclosed embodiments. On the contrary, the claims are intended to cover all modifications and equivalent combinations that are consistent with the essence and scope of the embodiments of this application. For example, although the system components described above can be implemented by hardware devices, they can also be implemented only by software solutions, such as installing the described system on an existing server or mobile device.
[0080] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more embodiments of the invention, in the above description of the embodiments of this application, multiple features are sometimes combined into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.
[0081] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values is as accurate as possible within the feasible range.
[0082] Each patent, patent application, patent application disclosure, and other materials, such as articles, books, instructions, publications, documents, etc., cited in this application are hereby incorporated by reference in their entirety. Except for application history documents that are inconsistent with or conflicting with the content of this application, documents that limit the broadest scope of the claims of this application (currently or later attached to this application) are also excluded. It should be noted that if the descriptions, definitions, and / or use of terms in the attached materials of this application are inconsistent or conflicting with the content described in this application, the descriptions, definitions, and / or use of terms in this application shall prevail.
[0083] Finally, it should be understood that the embodiments described in this application are only used to illustrate the principles of the embodiments of the present application. Other variations may also fall within the scope of the present application. Therefore, as an example and not a limitation, the alternative configurations of the embodiments of the present application may be considered to be consistent with the teachings of the present application. Accordingly, the embodiments of the present application are not limited to the embodiments explicitly introduced and described in the present application.
Claims
1. A method for determining a sweet spot in a thick lignite coal reservoir, characterized in that: The method comprises: According to the well logging electrical characteristics of the to-be-identified extremely thick lignite coal reservoir, the coal rock type of the to-be-identified extremely thick lignite coal reservoir is determined by utilizing the established mapping relationship between the coal rock type of the extremely thick lignite coal reservoir and the well logging electrical characteristics; According to the acoustic time difference and resistivity of the to-be-identified extremely thick lignite coal reservoir, the type of the pore structure of the to-be-identified extremely thick lignite coal reservoir is determined by using the established pore structure type identification plate of the extremely thick lignite coal reservoir; wherein the type of the pore structure is obtained by evaluating the results of nuclear magnetic resonance interpretation; According to the coal rock type and pore structure category of the to-be-identified extremely thick lignite coal reservoir, it is determined whether the to-be-identified extremely thick lignite coal reservoir is a sweet spot.
2. The method according to claim 1, characterized in that: The mapping relationship between the coal rock type and the well logging electrical characteristics of the thick lignite coal reservoir is established in the following way: According to the parameter data of each thick lignite coal reservoir, the coal rock type of the thick lignite coal reservoir is determined by coring observation; wherein the parameter data of the thick lignite coal reservoir is collected from coring wells, special logging wells or unknown wells; For each of the logging parameters of the thick lignite coal reservoir, the logging electrical characteristics of the thick lignite coal reservoir are determined by core homing; wherein the logging parameters are sensitive to the coal rock type of the thick lignite coal reservoir, and the logging parameters include: natural gamma, compensated density, and compensated neutron; According to the well logging electrical characteristics and coal rock type of each of the very thick lignite coal reservoirs, a mapping relationship between the type of the very thick lignite coal reservoir and the well logging electrical characteristics is obtained.
3. The method according to claim 1, characterized in that: The pore structure type identification plate is obtained by the following method: According to the nuclear magnetic resonance interpretation results of the pore structures of various thick lignite coal reservoirs, the pore structures of the various thick lignite coal reservoirs are classified to obtain various categories of pore structures; Establish the acoustic wave time difference-resistivity cross plot on the plane rectangular coordinate system; According to the acoustic time difference data and resistivity data of each of the thick lignite coal reservoirs, a plurality of coordinate points on the acoustic time difference-resistivity cross-plot are obtained; The pore structure type identification plate is obtained according to the categories of the pore structures corresponding to each of the plurality of coordinate points.
4. The method according to claim 1, characterized in that The step of determining whether the to-be-identified extremely thick lignite coal reservoir is a sweet spot according to the coal rock type and pore structure category of the to-be-identified extremely thick lignite coal reservoir comprises: In response to the coal rock type of the to-be-identified extremely thick lignite coal reservoir being high-quality coal rock, and the category of the pore structure being the first category, the to-be-identified extremely thick lignite coal reservoir is determined to be a sweet spot; wherein, the pore structure of the first category is the highest quality pore structure.
5. A device for determining the sweet spot section of a thick lignite coal reservoir, characterized in that: The device comprises: The first determination module is used to determine the coal rock type of the to-be-identified huge thick lignite coal reservoir according to the well logging electrical characteristics of the to-be-identified huge thick lignite coal reservoir and by using the established mapping relationship between the coal rock type of the to-be-identified huge thick lignite coal reservoir and the well logging electrical characteristics; The second determination module is used to determine the type of pore structure of the to-be-identified huge and thick lignite coal reservoir according to the acoustic wave time difference and resistivity of the to-be-identified huge and thick lignite coal reservoir, using the established pore structure type identification plate of the to-be-identified huge and thick lignite coal reservoir; wherein the type of pore structure is obtained by evaluating the results of nuclear magnetic interpretation; The third determination module determines whether the to-be-identified huge-thick lignite coal reservoir is a sweet spot according to the coal rock type and pore structure category of the to-be-identified huge-thick lignite coal reservoir.
6. The device according to claim 5, characterized in that The mapping relationship between the coal rock type and the well logging electrical characteristics of the thick lignite coal reservoir is established in the following way: According to the parameter data of each thick lignite coal reservoir, the coal rock type of the thick lignite coal reservoir is determined by coring observation; wherein the parameter data of the thick lignite coal reservoir is collected from coring wells, special logging wells or unknown wells; For each of the logging parameters of the thick lignite coal reservoir, the logging electrical characteristics of the thick lignite coal reservoir are determined by core homing; wherein the logging parameters are sensitive to the coal rock type of the thick lignite coal reservoir, and the logging parameters include: natural gamma, compensated density, and compensated neutron; According to the well logging electrical characteristics and coal rock type of each of the very thick lignite coal reservoirs, a mapping relationship between the type of the very thick lignite coal reservoir and the well logging electrical characteristics is obtained.
7. The device according to claim 5, characterized in that The pore structure type identification plate is obtained by the following method: According to the nuclear magnetic resonance interpretation results of the pore structures of various thick lignite coal reservoirs, the pore structures of the various thick lignite coal reservoirs are classified to obtain various categories of pore structures; Establish the acoustic wave time difference-resistivity cross plot on the plane rectangular coordinate system; According to the acoustic time difference data and resistivity data of each of the thick lignite coal reservoirs, a plurality of coordinate points on the acoustic time difference-resistivity cross-plot are obtained; The pore structure type identification plate is obtained according to the categories of the pore structures corresponding to each of the plurality of coordinate points.
8. The device according to claim 5, characterized in that The step of determining whether the to-be-identified extremely thick lignite coal reservoir is a sweet spot according to the coal rock type and pore structure category of the to-be-identified extremely thick lignite coal reservoir comprises: In response to the coal rock type of the to-be-identified extremely thick lignite coal reservoir being high-quality coal rock, and the category of the pore structure being the first category, the to-be-identified extremely thick lignite coal reservoir is determined to be a sweet spot; wherein, the pore structure of the first category is the highest quality pore structure.
9. An electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor executes the method according to any one of claims 1 to 4 when running the program.
10. A storage medium for storing a computer-readable program, wherein when the computer-readable program is executed, the method according to any one of claims 1 to 4 is executed.