Deep coal seam gas content prediction method and device, electronic equipment and storage medium

Abstract

The invention relates to a deep coal seam gas content prediction method and device, electronic equipment and a storage medium. The prediction method comprises the steps of obtaining drilling data of a target area; according to the well drilling data, a coal seam section and the maximum value of the logging gas logging total hydrocarbon value corresponding to the coal seam section are determined; and determining the gas content of the coal seam based on the maximum value of the logging gas logging total hydrocarbon value. According to the method, the gas content of the deep coal seam is predicted in a mode of measuring the total hydrocarbon value through logging gas, the mode is simple, convenient and fast, the effect is good, the method has important application value especially for the coal-seam-free pressure-maintaining coring well area, the gas content of the deep coal seam can be predicted in the coal-seam-free pressure-maintaining coring well area, and the method is suitable for large-scale popularization and application of the coal-seam-free pressure-maintaining coring well area. Meanwhile, compared with a mode of measuring the gas content through coal seam pressure-maintaining closed coring, the cost is greatly reduced, and an important supporting effect is achieved on development decision making of deep coal bed gas.

Description

Technical Field

[0001] The present invention relates to the technical field of natural gas geological exploration, and in particular, to a method, device, electronic device and storage medium for predicting the gas content of deep coal seams. Background Art

[0002] In recent years, the exploration of deep coalbed methane has been successful in the Carboniferous-Permian of the Ordos Basin in Inner Mongolia Autonomous Region and the Jurassic of the Baijiakai area in Xinjiang Uygur Autonomous Region, and has gradually become an important direction for future coalbed methane exploration. The primary task of developing deep coalbed methane is to measure the gas content of the coal seams in the target area. Deep coal seams generally refer to coal seams with a relatively deep burial depth.

[0003] Currently, the method for measuring the gas content of the coal seams in the target area is usually to measure the gas content by using a coal seam pressure-maintained closed coring. However, the coring cost is expensive and the operation is complex, and the prediction effect is not ideal. At the same time, in areas without coal seam pressure-maintained coring wells, how to carry out the prediction of the gas content of the coal seams has become a difficult problem for scientific researchers.

[0004] Therefore, in order to improve the prediction efficiency of the gas content of deep coal seams and reduce the cost required in the prediction process, it has become an urgent technical problem to propose a highly accurate and simple prediction method. Summary of the Invention

[0005] In view of this, the present invention provides a method that can accurately predict the gas content of deep coal seams and is simple and fast.

[0006] Specifically, the present invention is implemented through the following technical solutions:

[0007] According to a first aspect of the present invention, there is provided a method for predicting the gas content of deep coal seams, including obtaining drilling data of a target area; determining a coal seam section and the highest value of the total hydrocarbon value of the logging gas measurement corresponding to the coal seam section according to the drilling data; and determining the gas content of the deep coal seam based on the highest value of the total hydrocarbon value of the logging gas measurement.

[0008] In some embodiments, to determine the gas content of the deep coal seam based on the highest value of the total hydrocarbon value of the logging gas measurement, the following formula is used for calculation:

[0009] y = 3.86ln(x * 100) + 1.325;

[0010] where y represents the gas content of the deep coal seam, with the unit of m³ / t, and x represents the highest value of the total hydrocarbon value of the logging gas measurement corresponding to the coal seam section.

[0011] In some embodiments, the drilling data includes the total hydrocarbon value of gas logging, natural gamma log curve, acoustic travel time log curve, compensated density log curve, compensated neutron log curve, photoelectric absorption cross section index log curve, and gas logging lithology data.

[0012] In some embodiments, the steps of determining the coal seam section according to the drilling data include identifying the coal seam by combining the natural gamma log curve, acoustic travel time log curve, compensated density log curve, compensated neutron log curve, and photoelectric absorption cross section index log curve with the gas logging lithology data, determining the depth value of the deep coal seam, and determining the coal seam section according to the depth value of the deep coal seam.

[0013] In some embodiments, the steps of determining the highest value of the total hydrocarbon value of gas logging corresponding to the coal seam section include determining the set of the total hydrocarbon values of gas logging corresponding to the coal seam section; and determining the highest value of the total hydrocarbon value of gas logging according to the set of the total hydrocarbon values of gas logging.

[0014] In some embodiments, the burial depth of the deep coal seam is greater than 2000 meters.

[0015] In some embodiments, the deep coal seam contains hydrocarbon gases.

[0016] According to the second aspect of the present invention, there is provided a device for predicting the gas content of a deep coal seam, the device including: an acquisition unit for acquiring drilling data of a target area; a determination unit for determining a coal seam section and the highest value of the total hydrocarbon value of gas logging corresponding to the coal seam section according to the drilling data; and the determination unit is further configured to determine the gas content of the deep coal seam based on the highest value of the total hydrocarbon value of gas logging.

[0017] According to the third aspect of the present invention, there is provided an electronic device including a memory, a processor, and a computer program stored on the memory and executable on the processor, and when the processor executes the program, the steps of the method for predicting the gas content of a deep coal seam in the first aspect or any possible implementation manner of the first aspect are implemented.

[0018] According to the fourth aspect of the present invention, there is provided a storage medium having a computer program stored thereon, and when the program is executed by a processor, the steps of the method for predicting the gas content of a deep coal seam in the first aspect or any possible implementation manner of the first aspect are implemented.

[0019] The technical solution provided by the present invention at least brings the following beneficial effects: The present invention uses the method of logging gas total hydrocarbon value to quantitatively evaluate the gas content of deep coal seams. This method is simple, fast and effective, especially has important application value for areas without coal seam pressure-maintained coring wells, enabling the prediction of gas content in deep coal seams in areas without coal seam pressure-maintained coring wells. At the same time, compared with the method of measuring gas content by coal seam pressure-maintained closed coring, the cost is greatly reduced, which has an important supporting role for the development decision-making of deep coalbed methane. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings herein are incorporated into and constitute a part of this specification, showing embodiments in accordance with the present invention, and are used together with the specification to explain the principles of the present invention.

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or in the prior art, the following will briefly introduce the accompanying drawings required for use in the description of the embodiments or related technologies. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 It is a schematic flow chart of a method for predicting the gas content of deep coal seams provided in the first embodiment of the present invention;

[0023] Figure 2 It is a schematic flow chart of a method for predicting the gas content of deep coal seams provided in the second embodiment of the present invention;

[0024] Figure 3 It is a TJ1 comprehensive logging interpretation chart provided in the third embodiment of the present invention;

[0025] Figure 4 It is a schematic block diagram of a device for predicting the gas content of deep coal seams provided in an embodiment of the present invention;

[0026] Figure 5 It is a schematic block diagram of an electronic device provided in an embodiment of the present invention.

[0027] Among them, Figure 4 and Figure 5 The corresponding relationship between the reference numerals and the component names in is as follows:

[0028] 1 Device for predicting the gas content of deep coal seams, 10 Acquisition unit, 12 Determination unit, 2 Electronic device, 20 Memory, 22 Processor. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0030] See Figure 1 , an embodiment of the present invention provides a method for predicting the gas content of deep coal seams, which may include the following steps:

[0031] S102. Obtain the drilling data of the target area;

[0032] S104. Determine the coal seam section and the highest value of the total hydrocarbon value of gas logging corresponding to the coal seam section according to the drilling data;

[0033] S106. Determine the gas content of the deep coal seam based on the highest value of the total hydrocarbon value of gas logging.

[0034] According to the method for predicting the gas content of deep coal seams provided by the present invention, deep coal seam gas generally refers to methane gas contained in coal seams with a burial depth greater than 2000 meters, which is mainly adsorbed on the surface of coal matrix particles and partially free in coal pores or dissolved in coal seam water. The present invention uses the total hydrocarbon value of gas logging to quantitatively evaluate the gas content of deep coal seams. This method is simple, fast, and effective, especially has important application value for areas without coal seam pressure-maintained coring wells, enabling the prediction of the gas content of deep coal seams in areas without coal seam pressure-maintained coring wells. At the same time, compared with the method of measuring the gas content by coal seam pressure-maintained closed coring, the cost is greatly reduced, which has an important supporting role for the development decision-making of deep coal seam gas.

[0035] In the above embodiment, to determine the gas content of the deep coal seam based on the highest value of the total hydrocarbon value of gas logging, the following formula is used for calculation:

[0036] y = 3.86ln(x * 100) + 1.325;

[0037] Wherein, y represents the gas content of the deep coal seam, with the unit of m³ / t, and x represents the highest value of the total hydrocarbon value of gas logging corresponding to the coal seam section.

[0038] In this embodiment, by establishing the relationship between the total hydrocarbon value of gas logging and the gas content, and using the maximum value of the total hydrocarbon value of gas logging to quantitatively evaluate the gas content of deep coal seams, this method is simple, fast, and effective, and at the same time, the prediction cost is relatively low, which is applicable to the prediction of the gas content of coal seams in areas where the coal seam burial depth is greater than 2000 meters.

[0039] In the above embodiments, the drilling data includes the total hydrocarbon value of gas logging in well logging, the natural gamma logging curve, the acoustic travel time logging curve, the compensated density logging curve, the compensated neutron logging curve, the photoelectric absorption cross section index logging curve, and the well logging lithology data.

[0040] Of course, the drilling data is not limited to these data only. Any data that can affect the determination of the gas content in the coal seam should be regarded as drilling data, which will not be listed one by one here. Such data all vary with depth.

[0041] As Figure 2 shown, an embodiment of the present invention provides a method for predicting the gas content in deep coal seams, which may include the following steps:

[0042] S202. Obtain the drilling data of the target area;

[0043] S204. Based on the natural gamma logging curve, the acoustic travel time logging curve, the compensated density logging curve, the compensated neutron logging curve, and the photoelectric absorption cross section index logging curve in the drilling data, and in combination with the well logging lithology data, identify the coal seam and determine the depth value of the deep coal seam;

[0044] S206. Determine the coal seam section according to the depth value of the deep coal seam;

[0045] S208. Determine the highest value of the total hydrocarbon value of gas logging in well logging corresponding to the coal seam section;

[0046] S210. Determine the gas content in the deep coal seam based on the highest value of the total hydrocarbon value of gas logging in well logging.

[0047] According to the method for predicting the gas content in deep coal seams provided by the present invention, by obtaining the curve data of the exploration well that has drilled through the coal seam in the known target area, and in combination with the well logging lithology data, where the standard parameters of sandstone, mudstone or coal seam are given in the well logging lithology data, and comparing the curve data with the standard parameter data of coal. If the curve data conforms to the standard parameter data of coal, it is considered as the coal seam, and the depth of the coal seam can be accurately predicted, and the coal seam section can be determined according to the depth of the coal seam. For example, if the predicted depth of the coal seam in the target area is 2000 meters to 2200 meters, the coal seam section of 200 meters between the top and bottom of the coal seam can be determined.

[0048] In the above embodiments, the step of determining the highest value of the total hydrocarbon value of gas logging in well logging corresponding to the coal seam section includes determining the set of the total hydrocarbon values of gas logging in well logging corresponding to the coal seam section; and determining the highest value of the total hydrocarbon value of gas logging in well logging according to the set of the total hydrocarbon values of gas logging in well logging.

[0049] In this embodiment, since the total hydrocarbon value of mud logging gas measurement is data that varies with depth, the set of corresponding total hydrocarbon values of mud logging gas measurement can be determined according to the position of the coal seam section, and the highest value of the total hydrocarbon value of mud logging gas measurement can be determined from this set. The total hydrocarbon value of mud logging gas measurement is a percentage value. Thus, the gas content of deep coal seams is calculated using the highest value of the total hydrocarbon value of mud logging gas measurement. This method is simple, fast, and effective, and plays an important supporting role in the development decision-making of deep coalbed methane.

[0050] In the above embodiment, the burial depth of the deep coal seam is greater than 2000 meters.

[0051] In this embodiment, the prediction method for the gas content of deep coal seams of the present invention is applicable to areas where the burial depth of coal seams is greater than 2000 meters. The gas content of deep coal seams is quantitatively predicted using the mud logging gas measurement total hydrocarbon data of exploration wells with known coal seams drilled in the target area. In this way, the gas content of deep coal seams can also be predicted in areas without coal seam pressure-maintaining coring wells. At the same time, compared with the method of measuring gas content by coal seam pressure-maintaining closed coring, the cost is greatly reduced.

[0052] In the above embodiment, hydrocarbon gases are included in the deep coal seam.

[0053] In this embodiment, deep coalbed methane generally refers to methane gas contained in coal seams with a burial depth greater than 2000 meters, which is a hydrocarbon gas mainly adsorbed on the surface of coal matrix particles and partially free in coal pores or dissolved in coal seam water.

[0054] The embodiment of the present invention provides a prediction method for the gas content of deep coal seams, including the following steps:

[0055] (1) Collect drilling data of exploration wells with known coal seams drilled in the target area

[0056] Including but not limited to gas logging values, natural gamma logging curves, acoustic travel time logging curves, compensated density logging curves, compensated neutron logging curves, photoelectric absorption cross-section index logging curves, and mud logging lithology data. All the above data are data that vary with depth.

[0057] (2) Identification of the coal seam depth of the known well and determination of the total hydrocarbon value of mud logging gas measurement

[0058] Using the logging curve values and combining with the mud logging lithology data to identify the coal seam, determine the single-well coal seam depth value, and according to the data of the total hydrocarbon of mud logging gas measurement varying with depth, determine the highest value x of the total hydrocarbon of mud logging gas measurement in the coal seam section.

[0059] (3) Establish the relationship between the total hydrocarbon value of mud logging gas measurement and the gas content

[0060] y = 3.86ln(x * 100) + 1.325 Formula 1

[0061] Among them, y is the gas content of the coal seam, with the unit of m³ / t; x is the highest value of the total hydrocarbon in gas logging during well logging in the coal seam section, with the unit of %.

[0062] (4) Determine the gas content of the coal seam

[0063] Substitute the total hydrocarbon value x of the gas logging in the coal seam section in step 2 into formula 1 to calculate the gas content y of the coal seam.

[0064] The direct effect of the present invention is that it can quantitatively predict the gas content of the coal seam by using the total hydrocarbon data of gas logging in the exploration wells of the known coal seams drilled in the target area, which has the characteristics of simplicity, rapidity and low cost. Its applicable range is the area where the coal seam burial depth is greater than 2000 meters.

[0065] The total hydrocarbon value of gas logging is a gas logging method for directly measuring the content of combustible gas in drilling fluid during the drilling process. It can reflect the gas content of the drilled formation. By using gas logging data, oil and gas shows can be detected in time and well kicks can be predicted, so it is widely used in exploration wells.

[0066] Since the total hydrocarbon value of gas logging can reflect the natural gas content of the coal seam during the drilling process, the present invention quantitatively evaluates the gas content of deep coal seams based on the total hydrocarbon value of gas logging in coal seams. The method is simple, rapid and has good effects. Especially for areas without coal seam pressure-maintained coring wells, it has important application value, can greatly save coring costs, and at the same time has an important supporting role in the development decision-making of coalbed methane.

[0067] The embodiment of the present invention provides a method for predicting the gas content of deep coal seams, such as Figure 3 shown in the TJ1 comprehensive logging interpretation diagram. By collecting the data of the exploration well TJ1 with known coal seams drilled in the target block, including natural gamma logging curve, acoustic travel time logging curve and total hydrocarbon value of gas logging, etc., and using the logging curve identification coal seam data table in Table 1 below. Table 1 shows the standard parameters for determining coal, carbonaceous mudstone, mudstone and sandstone. Based on the comparison of the data at different depths in the data of the exploration well TJ1 with known coal seams drilled in the target block and the standard parameter data of coal in Table 1, the coal seam depth is accurately identified, and the coal seam depth is identified as 3304.5 - 3311 meters. And combined with Figure 3 , the highest total hydrocarbon value of gas logging corresponding to the coal seam depth is identified as 50%. Substitute the highest total hydrocarbon value of 50% into the formula y = 3.86ln(x * 100) + 1.325 to calculate the gas content of the coal seam as 16.42 m³ / t.

[0068] Table 1 Logging curve identification coal seam data table

[0069]

[0070] Based on the same inventive concept, such as Figure 4As shown in the figure, an embodiment of the present invention further provides a prediction device 1 for the gas content of deep coal seams. The device includes: an acquisition unit 10, configured to acquire drilling data of a target area; a determination unit 12, configured to determine a coal seam section and the highest value of the total hydrocarbon value of gas logging corresponding to the coal seam section according to the drilling data; the determination unit 12 is further configured to determine the gas content of the deep coal seam based on the highest value of the total hydrocarbon value of gas logging.

[0071] For the implementation processes of the functions and roles of each module in the above device, please refer to the implementation processes of the corresponding steps in the above method for details, which will not be elaborated here.

[0072] For the device embodiment, since it basically corresponds to the method embodiment, the relevant parts can refer to the partial description of the method embodiment. The device embodiment described above is only illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of the present invention. Those of ordinary skill in the art can understand and implement it without creative work.

[0073] Based on the same inventive concept, see Figure 5 , an embodiment of the present invention further provides an electronic device 2, including a memory 20 (such as a non-volatile memory), a processor 22, and a computer program stored on the memory 20 and executable on the processor 22. When the processor 22 executes the program, it implements the steps of the method for predicting the gas content of deep coal seams in any possible implementation manner, which is equivalent to the prediction device 1 for the gas content of deep coal seams as described above. Of course, the processor can also be used to process other data or operations. The electronic device 2 can be a device such as a PC, a server, or a terminal.

[0074] The electronic device 2 generally may further include: a memory, a network interface, and an internal bus. In addition to these components, other hardware may also be included, which will not be elaborated here.

[0075] It should be noted that the above electronic device 2 can be implemented by software. As a logically meaningful device, it is formed by the processor 22 of the electronic device 2 where it is located reading the computer program instructions stored in the non-volatile memory 20 into the memory for operation.

[0076] Based on the same inventive concept, an embodiment of the present invention further provides a storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the steps of the method for predicting the gas content of deep coal seams in any possible implementation manner.

[0077] Optionally, the storage medium may be a non-transitory computer-readable storage medium. For example, the non-transitory computer-readable storage medium may be ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device, etc.

[0078] Based on the same inventive concept, an embodiment of the present invention also provides a computer program product, including a computer program, which when executed by a processor, implements the steps of the prediction method for gas content in deep coal seams in any of the above possible implementation manners.

[0079] In an embodiment according to the present invention, the terms "first", "second", and "third" are only used for descriptive purposes and should not be construed as indicating or implying relative importance; the term "plurality" means two or more, unless otherwise clearly defined. Terms such as "installed", "connected", "coupled", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "coupled" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments according to the present invention can be understood according to specific circumstances.

[0080] In addition, although the operations are depicted in a particular order, this should be understood as requiring that such operations be performed in the particular order shown or in a sequential order, or that all illustrated operations be performed to achieve the desired result. In certain environments, multitasking and parallel processing may be advantageous. Similarly, although several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of the present invention. Certain features described in the context of separate embodiments may also be implemented combinatorially in a single implementation. Conversely, the various features described in the context of a single implementation may also be implemented separately or in any suitable sub-combination in multiple implementations.

[0081] Although the subject matter has been described in language specific to structural features and / or methodological logical acts, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. On the contrary, the specific features and acts described above are merely example forms for implementing the claims.

[0082] The above are only the preferred embodiments according to the embodiments of the present invention and are not used to limit the embodiments according to the present invention. For those skilled in the art, various changes and modifications can be made according to the embodiments of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiments according to the present invention shall be included within the protection scope of the embodiments according to the present invention.

Claims

1. A method for predicting the gas content of deep coal seams, characterized in that, it includes: Obtaining drilling data of the target area; According to the drilling data, determining the coal seam section and the highest value of the total hydrocarbon value of the logging gas measurement corresponding to the coal seam section; Based on the highest value of the total hydrocarbon value of the logging gas measurement, determining the gas content of the deep coal seam.

2. The method for predicting the gas content of deep coal seams according to claim 1, characterized in that, for the step of determining the gas content of the deep coal seam based on the highest value of the total hydrocarbon value of the logging gas measurement, the following formula is used for calculation: y = 3.86ln(x * 100) + 1.325; wherein, y represents the gas content of the deep coal seam, with the unit of m³ / t, x represents the highest value of the total hydrocarbon value of the logging gas measurement corresponding to the coal seam section, and 3.86 and 1.325 are constants.

3. The method for predicting the gas content of deep coal seams according to claim 1, characterized in that, the drilling data includes the total hydrocarbon value of the logging gas measurement, natural gamma logging curve, acoustic travel time logging curve, compensated density logging curve, compensated neutron logging curve, photoelectric absorption cross section index logging curve and logging lithology data.

4. The method for predicting the gas content of deep coal seams according to claim 3, characterized in that, the step of determining the coal seam section according to the drilling data includes: Based on the natural gamma logging curve, the acoustic travel time logging curve, the compensated density logging curve, the compensated neutron logging curve and the photoelectric absorption cross section index logging curve, combined with the logging lithology data for coal seam identification, determining the depth value of the deep coal seam, and according to the depth value of the deep coal seam, determining the coal seam section.

5. The method for predicting the gas content of deep coal seams according to claim 3, characterized in that, the step of determining the highest value of the total hydrocarbon value of the logging gas measurement corresponding to the coal seam section includes: Determining the set of total hydrocarbon values of the logging gas measurement corresponding to the coal seam section; According to the set of total hydrocarbon values of the logging gas measurement, determining the highest value of the total hydrocarbon value of the logging gas measurement.

6. The method for predicting the gas content of deep coal seams according to any one of claims 1 to 5, characterized in that, the burial depth of the deep coal seam is greater than 2000 meters.

7. The method for predicting the gas content of deep coal seams according to any one of claims 1 to 5, characterized in that, the deep coal seam includes hydrocarbon gases.

8. A device for predicting the gas content of deep coal seams, characterized in that, it includes: An acquisition unit for acquiring drilling data of the target area; A determination unit for determining the coal seam section and the highest value of the total hydrocarbon value of the logging gas measurement corresponding to the coal seam section according to the drilling data; The determination unit is further configured to determine the gas content of the deep coal seam based on the highest value of the total hydrocarbon value of the logging gas measurement.

9. An electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, when the processor executes the computer program, the steps of the method for predicting the gas content of deep coal seams according to any one of claims 1 to 7 are implemented.

10. A storage medium, on which a computer program is stored, It is characterized in that when the computer program is executed by a processor, the steps of the prediction method for the gas content in deep coal seams described in any one of claims 1-7 are implemented.

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