Lithology information confirmation method and device, storage medium and electronic equipment

Abstract

The invention relates to a lithology information confirmation method and device, a storage medium and electronic equipment, and the lithology information confirmation method comprises the steps: obtaining the logging data of a coal measure stratum; fitting a logging curve according to the logging data; and determining lithology information of the coal measure strata according to curve characteristics in the logging curve.

Description

Technical Field

[0001] The present invention relates to the technical field of deep oil and gas geological exploration, and particularly relates to a method and device for confirming lithologic information, a storage medium, and an electronic device. Background Art

[0002] In the related art, drilling cores and logging are used to identify coal-bearing strata. However, limited by factors such as the large burial depth of Paleozoic coal-bearing strata, few coring wells, incomplete intervals, and lack of discrimination information, there are problems such as large standard differences, missed judgments, and misjudgments, and there is a lack of accurate and popularizable discrimination criteria to accurately identify coal-bearing strata. Therefore, how to accurately and quickly complete the lithologic discrimination of coal seams has become an urgent problem to be solved. Summary of the Invention

[0003] In view of this, the present invention provides a method and device for confirming lithologic information of coal-bearing strata, a storage medium, and an electronic device.

[0004] Specifically, the present invention is implemented through the following technical solutions:

[0005] According to a first aspect of the present invention, there is provided a method for confirming lithologic information of coal-bearing strata, the method including: obtaining logging data of coal-bearing strata; fitting a logging curve according to the logging data; and determining the lithologic information of the coal-bearing strata according to curve features in the logging curve.

[0006] The method for confirming lithologic information of coal-bearing strata provided by the present invention obtains the logging data of coal-bearing strata, fits a logging curve according to each parameter included in the logging data. Thus, different curve features (i.e., the undulating features of the curve) formed by the numerical magnitudes of each parameter in the logging data can be shown on the logging curve. Through the curve features, the highs and lows of the numerical values of each parameter can be intuitively obtained. By combining the curve features of multiple parameters, the lithologic information of the coal-bearing strata can be determined. Among them, the lithologic information of the coal-bearing strata includes mudstone information, carbonaceous mudstone information, and coal rock information.

[0007] For example, well logging data includes acoustic transit time parameter (AC, Acoustic, abbreviation of well logging curve symbol), density parameter (DEN, Density, abbreviation of well logging curve symbol), deep lateral resistivity parameter (RD, deep investigate lateral resistivity log, abbreviation of well logging curve symbol), and natural gamma parameter (GR, natural gamma ray, abbreviation of well logging curve symbol), resistivity (RT, resistivity, abbreviation of well logging curve symbol). The corresponding value ranges are as follows: the GR value is 7 - 40 API (American Petroleum Institute, unit symbol), the DEN value is 1.2 - 1.3 g / cm3 (gram per cubic centimeter, unit symbol), the AC value is 403 - 423 μs / m (microsecond per meter, unit symbol), and the RT value is 300 - 330 ohm·m (ohm meter, unit symbol). The curve characteristics shown on the well logging curve are low GR, low DEN, high AC, and high RT. And low GR, low DEN, high AC, and high RT correspond to the lithologic information of coal rock. Therefore, the lithologic information can be quickly determined in the above manner. Of course, shale information and carbonaceous shale information can also be obtained by the above method.

[0008] It should be noted that the curve characteristics refer to the amplitude of the curve undulation. When the parameter value is relatively high, the position amplitude of the corresponding curve is relatively large, and the curve characteristic is high. The determination of whether the parameter value is high or low is based on the full coring of the well section, and through core observation and microscopic thin section observation, the well logging curve and the core are aligned to determine the quantitative value range of the well logging data of the coal measure strata. That is, the ranges of each parameter in the well logging data are limited in the above manner. In a certain value range of a parameter, the corresponding curve characteristic is high or low.

[0009] The present invention determines the lithologic information of the coal measure strata through the curve characteristics in the well logging curve, not only realizes the rapid identification of the coal measure source rock, thus guiding the breakthrough and production increase of deep oil and gas exploration in the oilfield, but also provides evidence for the well logging curve to identify the coal measure strata, achieving a method for quickly identifying the coal measure strata during the drilling process, improving the accuracy of identifying the coal measure strata, and providing technical support for the "Paleozoic reservoir in Paleozoic strata" buried hill exploration.

[0010] In addition, the method for determining the lithologic information of the coal measure strata in the above technical solution provided by the present invention may further have the following additional technical features:

[0011] In the above technical solution, further, the steps of determining the lithologic information of the coal measure strata according to the curve characteristics of the well logging curve include: obtaining the curve characteristics of the well logging curve; if the curve characteristics match the preset characteristics, taking the corresponding information of the preset characteristics as the lithologic information of the coal measure strata.

[0012] In this technical solution, the curve characteristics of the logging curve are obtained and matched with the preset characteristics. If the matching result of the curve characteristics and the preset characteristics is consistent, the lithology information corresponding to the preset characteristics is used as the lithology information of the curve. In this way, the lithology of the coal measure strata can be quickly, comprehensively and accurately identified, which also lays a foundation for the rapid evaluation of the coal measure source rocks.

[0013] Specifically, the curve characteristics of the logging curve include the undulation amplitude of the curve formed by the specific values of each parameter. For example, the logging data includes acoustic time difference parameter (AC), density parameter (DEN), deep lateral parameter (RD) and natural gamma parameter (GR). The value ranges of the above parameters are as follows: the GR value is 7-40 API, the DEN value is 1.2-1.3 g / cm3, the AC value is 403-423 μs / m, and the RT value is 300-330 ohm·m. The curve characteristics shown on the logging curve are low GR, low DEN, high AC and high RT. And low GR, low DEN, high AC and high RT correspond to the lithology information of coal rock. Therefore, the lithology information can be quickly determined according to the above method. Of course, the mudstone information and carbonaceous mudstone information can also be obtained by the above method.

[0014] In the above technical solution, further, the logging data includes multiple logging parameters. The step of determining the lithology information of the coal measure strata according to the curve characteristics of the logging curve further includes: combining two of the multiple logging parameters to form a logging parameter set, matching the logging parameter set with the standard parameter set, and determining the lithology information of the coal measure strata according to the matching result.

[0015] In this technical solution, the logging data includes multiple logging parameters. Specifically, two of the multiple logging parameters are combined to form a logging parameter set. The values of the two parameters in the logging parameter set are matched with the value ranges of the corresponding parameters in the standard parameter set. When the two logging parameters meet the ranges of the two standard parameters in the standard parameter set, the lithology information corresponding to the standard parameter set is used as the lithology information of the coal measure strata. Through the above determination method, it provides a basis for quickly identifying the coal measure strata by using the logging curve. It can be understood that the two standard parameters in the standard parameter set are in one-to-one correspondence with the types of the two logging parameters in the logging parameter set.

[0016] Among them, the standard parameter set is obtained by fitting multiple logging curves of coal measures strata based on the fine analysis of single-well logging curves to form a logging curve crossplot. Through the crossplot analysis of the values of GR, AC, and DEN on the logging curve crossplot, the lithology information corresponding to the standard parameter set is obtained. By establishing the logging curve crossplot of coal measures strata, a basis is provided for quickly identifying coal measures strata using logging curves. Specifically, the relationship between the numerical ranges of two standard parameters in the standard parameter set and the lithology information is as follows:

[0017] Shale is within the range of [AC (200 - 300): GR (80 - 140)], coal rock is within the range of [AC (390 - 500): GR (20 - 75)], and carbonaceous shale is within the range of [AC (300 - 380): GR (75 - 130)]; for the standard chart of the DEN - GR crossplot of logging curves, shale is within the range of [DEN (2.4 - 2.8): GR (80 - 140)], coal rock is within the range of [DEN (1.2 - 1.6): GR (20 - 75)], and carbonaceous shale is within the range of [DEN (1.8 - 2.4): GR (75 - 130)].

[0018] In the above technical solution, further, after the step of determining the lithology information of coal measures strata according to the curve characteristics of logging curves, it further includes: performing X-ray diffraction analysis and maceral analysis on the coal measures strata to verify the accuracy of the lithology information.

[0019] In this technical solution, through X-ray diffraction analysis (phase analysis of xray diffraction, abbreviated as XRD analysis) and maceral analysis, the accuracy of the lithology information quickly identified according to curve characteristics can be determined.

[0020] In the above technical solution, further, the lithology information of coal measures strata includes coal rock information. After the step of performing X-ray diffraction analysis and maceral analysis on the coal measures strata to verify the accuracy of the lithology information, it further includes: determining the industrial component information corresponding to the coal rock information according to multiple logging parameters; determining the coal rank information corresponding to the coal rock information according to the industrial component information.

[0021] In this technical solution, after determining the coal rock information included in the lithology information of coal measures strata, the coal rank information corresponding to the coal rock information is determined according to multiple logging parameters and coal rock analysis data. By determining the coal rank information, it is convenient to carry out fine evaluation of coal rock.

[0022] In the above technical solution, further, the method for confirming the lithology information of coal measures strata further includes: determining the structural information corresponding to the coal rock information according to multiple logging parameters, where the structural information includes primary structure, fragmented structure, and granular structure.

[0023] In this technical solution, through the acoustic travel time parameter, deep lateral resistivity parameter, and natural gamma parameter among multiple logging parameters, the structural information of coal and rock can be determined, where the structural information includes primary structure, fragmented structure, and granular structure. Since the structural information of coal seams is an important controlling factor for coal seam gas content, it thus lays a foundation for the evaluation and exploration of coalbed methane.

[0024] In the above technical solution, further, the method for confirming the lithological information of coal measures strata further includes: determining the coal seam gas content corresponding to the coal and rock information according to multiple logging parameters.

[0025] In this technical solution, through multiple logging parameters, the coal seam gas content corresponding to the coal and rock information is determined. Since the coal seam gas content is a decisive index for the development rating of coalbed methane, obtaining the gas content of coal seams is of great significance for the development of coalbed methane.

[0026] Among them, the coal seam gas content corresponding to the coal and rock information can be determined according to the relational formula between the coal and rock gas content and logging parameters.

[0027] Specifically, according to the density parameter (DEN) in the logging parameters or the relational formula between the coal and rock gas content and the acoustic travel time parameter (AC), the coal and rock gas content is determined. The relational formulas are as follows: Coal and rock gas content = 17.844 × DEN + 33.488, and the relational formula between the coal and rock gas content and the acoustic travel time parameter: Coal and rock gas content = 0.0441 × AC - 10.6529.

[0028] According to the second aspect of the present invention, there is provided a device for confirming the lithological information of coal measures strata, and the device includes a module for executing the method for confirming the lithological information of coal measures strata in the first aspect or any possible implementation manner of the first aspect.

[0029] The device for confirming the lithological information of coal measures strata includes:

[0030] An acquisition module for acquiring logging data of coal measures strata;

[0031] A processing module for fitting a logging curve according to the logging data;

[0032] A determination module for determining the lithological information of coal measures strata according to the curve characteristics of the logging curve.

[0033] The confirmation device for lithological information of coal measures strata provided by the present invention includes an acquisition module, a processing module, and a determination module. The logging data of the coal measures strata is acquired, and logging curves are fitted based on each parameter included in the logging data. Thus, different curve characteristics (i.e., undulation characteristics of the curves) formed by the numerical values of each parameter in the logging data can be shown on the logging curves. Through the curve characteristics, the high and low of the numerical values of each parameter can be intuitively obtained. By combining the curve characteristics of multiple parameters, the lithological information of the coal measures strata can be determined. Among them, the lithological information of the coal measures strata includes mudstone information, carbonaceous mudstone information, and coal rock information.

[0034] According to the third aspect of the present invention, there is provided a storage medium on which a computer program is stored. When the program is executed by a processor, the steps of the method for confirming the lithological information of coal measures strata in the first aspect or any possible implementation manner of the first aspect are implemented.

[0035] According to the fourth 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. When the processor executes the program, the steps of the method for confirming the lithological information of coal measures strata in the first aspect or any possible implementation manner of the first aspect are implemented.

[0036] The technical solution provided by the present invention at least brings the following beneficial effects:

[0037] The method of the present invention identifies the lithological information of coal measures strata through logging curve characteristics; and based on a large number of tests of XRD analysis data and maceral data, it provides evidence for the logging curve to identify coal measures strata, realizes the rapid identification of the lithological information of coal measures strata during the drilling process, improves the identification accuracy of coal measures strata, and provides technical support for the "Paleozoic reservoir in Paleozoic buried hill" exploration. Description of the Drawings

[0038] The drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present invention, and are used together with the specification to explain the principles of the present invention.

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or related technologies. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0040] Figure 1 It is one of the schematic flowcharts of the method for determining the lithological information of coal measures strata provided by the embodiment of the present invention;

[0041] Figure 2 It is the second schematic flowchart of the method for determining the lithological information of coal measures strata provided by the embodiment of the present invention;

[0042] Figure 3 It is the third schematic flow chart of the method for determining the lithological information of coal measures strata provided by the embodiments of the present invention;

[0043] Figure 4 It is the fourth schematic flow chart of the method for determining the lithological information of coal measures strata provided by the embodiments of the present invention;

[0044] Figure 5 It is the structural block diagram of the device for confirming the lithological information of coal measures strata provided by the embodiments of the present invention;

[0045] Figure 6 It is the structural block diagram of the electronic device provided by the embodiments of the present invention;

[0046] Figure 7 It is the lithological map of coal measures strata of logging curves provided by the embodiments of the present invention;

[0047] Figure 8 It is one of the comprehensive columnar diagrams of the rock-electricity relationship of coal measures strata provided by the embodiments of the present invention;

[0048] Figure 9 It is one of the crossplot diagrams of logging curves of coal measures strata provided by the embodiments of the present invention;

[0049] Figure 10 It is the second crossplot diagram of logging curves of coal measures strata provided by the embodiments of the present invention;

[0050] Figure 11 It is the lithology determination diagram of XRD data of coal measures strata provided by the embodiments of the present invention;

[0051] Figure 12 It is the standard determination diagram of macerals of coal measures strata provided by the embodiments of the present invention;

[0052] Figure 13 It is the fine calculation diagram of industrial components of coal seams provided by the embodiments of the present invention;

[0053] Figure 14 It is one of the evaluation diagrams of coal seam structures provided by the embodiments of the present invention;

[0054] Figure 15 It is the gas content calculation diagram provided by the embodiments of the present invention;

[0055] Figure 16 It is the second comprehensive columnar diagram of the rock-electricity relationship of coal measures strata provided by the embodiments of the present invention;

[0056] Figure 17 It is the third crossplot diagram of logging curves of coal measures strata provided by the embodiments of the present invention;

[0057] Figure 18It is the fourth cross-plot of well logging curves of coal measures strata provided by the embodiments of the present invention;

[0058] Figure 19 It is the discrimination diagram of macerals in coal measures strata provided by the embodiments of the present invention;

[0059] Figure 20 It is the second evaluation diagram of coal seam structure provided by the embodiments of the present invention; Detailed implementation manners

[0060] 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. Obviously, 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 protection scope of the present invention.

[0061] Figure 1 Schematically shows one of the flow diagrams of the method for confirming the lithology information of coal measures strata in an embodiment of the present invention. Among them, the method includes:

[0062] Step S102, obtaining well logging data of coal measures strata;

[0063] Step S104, fitting well logging curves according to the well logging data;

[0064] Step S106, determining the lithology information of coal measures strata according to the curve characteristics in the well logging curves.

[0065] For the method for confirming the lithology information of coal measures strata provided by the present invention, the well logging data of coal measures strata is obtained, and well logging curves are fitted according to each parameter included in the well logging data. Thus, different curve characteristics (i.e., the undulating characteristics of the curves) formed by the numerical values of each parameter in the well logging data can be shown on the well logging curves. Through the curve characteristics, the high and low of the numerical values of each parameter can be intuitively obtained. Combining the curve characteristics of multiple parameters, the lithology information of coal measures strata can be determined. Among them, the lithology information of coal measures strata includes mudstone information, carbonaceous mudstone information and coal rock information.

[0066] The well logging data includes acoustic time difference parameter (AC), density parameter (DEN), deep lateral parameter (RD) and natural gamma parameter (GR). As Figure 7 shown, the well logging curve characteristics of coal rock are low GR, low DEN, high AC and high RT. The GR value is 7 - 40 API, and the DEN value is 1.2 - 1.3 g / cm 3, the AC value is 403 - 423 us / m, and the RT value is 300 - 330 ohm.m; the logging curve characteristics of carbonaceous mudstone are high GR, medium - high AC, high DEN, and low RT. The GR value is 70 - 110 API, the AC value is 300 - 340 us / m, and the DEN value is 2 - 2.3 g / cm 3 , the RT value is 5 - 10 ohm.m; the logging curve characteristics of mudstone are high GR, medium AC, high DEN, and low RT. The GR value is 70 - 120 API, the AC value is 250 - 300 us / m, and the DEN value is 1.2 - 1.4 g / cm 3 , the RT value is 5 - 10 ohm.m. Therefore, the lithology information can be quickly determined according to the above method.

[0067] The present invention identifies the lithology information of the coal - measure strata through the logging curve characteristics, realizes the rapid identification of the lithology of the coal - measure strata during the drilling process, improves the accuracy of the identification of the coal - measure strata, and provides technical support for the exploration of "paleozoic source rocks in paleozoic reservoirs".

[0068] Figure 2 Schematically shows the second flow chart of the method for confirming the lithology information of the coal - measure strata according to an embodiment of the present invention. Among them, the steps of determining the lithology information of the coal - measure strata according to the curve characteristics of the logging curve include:

[0069] Step S202, obtain the curve characteristics of the logging curve;

[0070] Step S204, if the curve characteristics match the preset characteristics, use the lithology information corresponding to the preset characteristics as the lithology information of the coal - measure strata.

[0071] In this embodiment, the curve characteristics of the logging curve are obtained and matched with the preset characteristics. If the matching result of the curve characteristics and the preset characteristics is consistent, the lithology information corresponding to the preset characteristics is used as the lithology information of the curve. In this way, the lithology of the coal - measure strata can be quickly, comprehensively and accurately identified, and it also lays a foundation for the rapid evaluation of the coal - measure source rocks.

[0072] Specifically, as Figure 8 shown, the curve characteristics of the logging curve include multiple logging parameters. The high and low values of the parameter values are manifested as the high and low undulations of the curve on the logging curve, that is, if the parameter value is high, the curve characteristic is high; conversely, if the parameter value is low, the curve characteristic is low. The performance of the coal rock information corresponding to the curve characteristics is low GR, low DEN, high AC, and high RT. The performance of the carbonaceous mudstone information corresponding to the curve characteristics is high GR, medium - high AC, high DEN, and low RT. The performance of the mudstone information corresponding to the curve characteristics is high GR, medium AC, high DEN, and low RT. The specific values are shown in Figure 7 and Figure 8, whose logging curve characteristics can be used as important features for accurately identifying the lithology of coal-bearing strata. The parameter differences between carbonaceous mudstone and mudstone curves are relatively small, and there are differences in the AC and DEN values.

[0073] Figure 3 Schematically shows the third flow chart of the method for confirming the lithology information of coal-bearing strata according to an embodiment of the present invention. Among them, the logging parameters include multiple logging parameters. According to the curve characteristics of the logging curves, the steps for determining the lithology information of coal-bearing strata include:

[0074] Step S302: Combine two of the multiple logging parameters to form a set of logging parameters;

[0075] Step S304: Match the set of logging parameters with the set of standard parameters, and determine the lithology information of the coal-bearing strata according to the matching result.

[0076] In this embodiment, the logging data includes multiple logging parameters. Specifically, two of the multiple logging parameters are combined to form a set of logging parameters. The numerical values of the two parameters in the set of logging parameters are matched with the numerical value ranges of the corresponding parameters in the set of standard parameters. When the two logging parameters meet the ranges of the two standard parameters in the set of standard parameters, the lithology information corresponding to the set of standard parameters is used as the lithology information of the coal-bearing strata. Through the above determination method, it provides a basis for quickly identifying coal-bearing strata using logging curves.

[0077] It can be understood that the two standard parameters in the set of standard parameters correspond one-to-one with the types of the two logging parameters in the set of logging parameters.

[0078] Among them, the set of standard parameters is based on the fine analysis of single-well logging curves. For example, Figure 9 and Figure 10 As shown in the logging curve crossplot, multiple logging curves of coal-bearing strata are fitted to form a logging curve crossplot. By performing crossplot analysis on the GR, AC, and DEN values on the logging curve crossplot, the lithology information corresponding to the set of standard parameters is obtained. By establishing a logging curve crossplot of coal-bearing strata, it provides a basis for quickly identifying coal-bearing strata using logging curves.

[0079] Specifically, as shown in Figure 9 and Figure 10 the logging curve crossplot, the relationship between the numerical value ranges of the two standard parameters in the set of standard parameters and the lithology information is as follows:

[0080] The range of [AC(200 - 300): GR(80 - 140)] is mudstone, the range of [AC(390 - 500): GR(20 - 75)] is coal rock, and the range of [AC(300 - 380): GR(75 - 130)] is carbonaceous mudstone; for the standard chart of the DEN - GR cross - plot of well - logging curves, the range of [DEN(2.4 - 2.8): GR(80 - 140)] is mudstone, the range of [DEN(1.2 - 1.6): GR(20 - 75)] is coal rock, and the range of [DEN(1.8 - 2.4): GR(75 - 130)] is carbonaceous mudstone.

[0081] In the above - mentioned embodiment, further, after the step of determining the lithology information of the coal - bearing strata according to the curve characteristics of the well - logging curves, the following steps are also included: performing X - ray diffraction treatment and maceral treatment on the strata of the coal - bearing series to verify the accuracy of the lithology information.

[0082] In this embodiment, through X - ray diffraction analysis (phase analysis of xray diffraction, abbreviated as XRD analysis) and maceral analysis, the accuracy of the lithology information quickly identified according to the curve characteristics can be determined.

[0083] Figure 11 Shows the lithology determination chart of XRD data of the coal - bearing strata. XRD whole - rock analysis has been carried out on the cored well or cuttings of the coal - bearing strata (mudstone, carbonaceous mudstone, coal seam). Among them, authigenic minerals such as felsic, clay minerals, and siderite + pyrite have good discrimination for the coal - bearing strata. Based on the XRD data analysis of the measured coal - bearing strata, a lithology discrimination chart of XRD data of the coal - bearing strata has been established. Among them, coal rock is "low felsic, high clay minerals, low siderite + pyrite", and the relative content range of its minerals is [felsic(40 - 60%), clay minerals(40 - 50%), siderite + pyrite(<5%)]; carbonaceous mudstone is "medium felsic, high clay minerals, high siderite + pyrite", and the relative content of its minerals is [felsic(60 - 80%), clay minerals(20 - 35%), siderite + pyrite(20 - 35%)]; mudstone is "high felsic, low clay minerals, low siderite + pyrite", and the relative content of its minerals is [felsic(85 - 95%), clay minerals(<15%), siderite + pyrite(<10%)].

[0084] Figure 12 Shows the standard determination chart of the macerals of the coal - bearing strata. According to the maceral data, a comprehensive recognition triangular chart is used, such as Figure 12As shown, vitrinite, exinite, and inertinite have good discrimination for coal measures strata; the coal rock is "high vitrinite, low exinite, low inertinite", and the content range of its macerals is [vitrinite (60-90%), exinite (0-30%), inertinite (0-30%)]; the carbonaceous mudstone is "high vitrinite, medium exinite, medium inertinite", and the content range of its macerals is [vitrinite (80-90%), exinite (20-40%), inertinite (30-40%)]; the mudstone is "vitrinite and exinite dispersed, medium-low inertinite", and the content range of its macerals is [the distribution range of vitrinite and exinite is large, inertinite (0-50%)].

[0085] Figure 4 Schematically shows the fourth flow chart of the method for confirming the lithologic information of the coal measures strata of an embodiment of the present invention. Among them, the lithologic information of the coal measures strata includes coal rock information. After the steps of performing X-ray diffraction analysis and maceral analysis on the strata of the coal measures to verify the accuracy of the lithologic information, it further includes:

[0086] Step S402: Determine the industrial component information corresponding to the coal rock information according to multiple logging parameters;

[0087] Step S404: Determine the coal rank information corresponding to the coal rock information according to the industrial component information.

[0088] In this embodiment, after determining the coal rock information included in the lithologic information of the coal measures strata, the coal rank information corresponding to the coal rock information is determined according to multiple logging parameters and coal rock analysis data. By determining the coal rank information, it is convenient to carry out fine evaluation of coal rock. Among them, the coal rank information includes low coal rank, medium coal rank, and high coal rank.

[0089] Figure 13 Shows the fine calculation diagram of the industrial components of the coal seam, including the calculation formulas and calculation conditions of low, medium, and high coal rank components.

[0090] The industrial component calculation formulas for Gg16102 low-rank coal, medium-rank coal, and high-rank coal are also shown as follows: ① Low-rank coal: Ash (VHFL) = 106.32 - 0.42 × AC + 53.53 × DEN, Fixed carbon (VCLL) = -0.65 × VHFL + 64.04, Moisture (VWAT) = -0.018 × MHFL + 2.32, Volatile matter (VHFF) = 100 - VWAT - VHFL - VCLL; ② Medium-rank coal: Ash (VHFL) = 6.12 - 0.074 × AC + 27.69 × DEN, Fixed carbon (VCLL) = -1.30 × VHFL + 90.85, Moisture (VWAT) = 0.011 × VHFL + 0.56, Volatile matter (VHFF) = 100 - VWAT - VHFL - VCLL; ③ High-rank coal: Ash (VHFL) = -65.97 - 0.13 × AC + 98.76 × DEN, Fixed carbon (VCLL) = -0.99 × VHFL + 87.28, Moisture (VWAT) = -0.009 × MHFL + 0.704, Volatile matter (VHFF) = 100 - VWAT - VHFL - VCLL.

[0091] In the above embodiment, further, the method for confirming the lithological information of the coal-bearing strata further includes: determining the structural information corresponding to the coal-rock information according to a plurality of logging parameters, wherein the structural information includes primary structure, fractured structure, and fragmented structure.

[0092] In this embodiment, through the acoustic time difference parameter, deep lateral parameter, and natural gamma parameter in a plurality of logging parameters, the structural information of the coal-rock can be determined, wherein the structural information includes primary structure, fractured structure, and fragmented structure. Since the structural information of the coal seam is an important controlling factor for the gas content of the coal seam, determining the structural information of the coal seam lays a foundation for the evaluation and exploration of the gas content of the coal seam.

[0093] Figure 14An evaluation diagram of the coal seam structure is shown, showing the evaluation of the coal seam structure. Based on the curve characteristics of the acoustic travel time parameter (AC) and the degree of hole enlargement (hole diameter / drill bit diameter), and combined with the deep lateral parameter (RD) and the natural gamma parameter (GR), the structure of the coal seam is qualitatively judged. The primary structure has a high acoustic travel time parameter (400 - 450 μs / m), a low natural gamma parameter (30 - 50 API), a high resistivity parameter (>1000 Ω·m), and a small degree of hole enlargement (<1.05); the fragmented structure has a high acoustic travel time parameter (350 - 400 μs / m), a medium natural gamma parameter (80 - 100 API), a low resistivity parameter (800 Ω·m - 1000 Ω·m), and a large degree of hole enlargement (about 1.1); the granular structure has a low acoustic travel time parameter (<350 μs / m), a high natural gamma parameter (>120 API), a low resistivity parameter (800 Ω·m - 1000 Ω·m), and a small degree of hole enlargement (>1.1). In the above embodiment, further, the method for confirming the lithology information of the coal measure strata further includes: determining the gas content of the coal seam corresponding to the coal rock information according to multiple logging parameters.

[0094] In this embodiment, the gas content of the coal seam corresponding to the coal rock information is determined through multiple logging parameters. Since the gas content of the coal seam is a decisive index for the development rating of coalbed methane, therefore, obtaining the gas content of the coal seam is of great significance for the development of coalbed methane.

[0095] Among them, the gas content of the coal seam corresponding to the coal rock information can be determined according to the relational formula between the gas content of the coal rock and the logging parameters.

[0096] Specifically, according to the density parameter (DEN) in the logging parameters or the relational formula between the gas content of the coal rock and the acoustic travel time parameter (AC), the gas content of the coal rock is determined. The relational formulas are as follows: gas content = 17.844×DEN + 33.488, and the relational formula between the gas content of the coal rock and the acoustic travel time parameter: gas content = 0.0441×AC - 10.6529.

[0097] Figure 15 The calculation of the gas content of the coal seam by the density parameter and the acoustic travel time parameter is shown respectively.

[0098] Based on the same inventive concept, as Figure 5 shown, an apparatus 500 for determining the lithology information of coal measure strata according to an embodiment of the present invention is further provided, wherein the apparatus 500 for determining the lithology information of coal measure strata includes:

[0099] An acquisition module 502, configured to acquire logging data of coal measure strata;

[0100] A processing module 504, configured to fit a logging curve according to the logging data;

[0101] A determination module 506 is configured to determine the lithology information of the coal-bearing strata according to the curve characteristics of the logging curves.

[0102] The confirmation device for the lithology information of the coal-bearing strata provided by the present invention includes an acquisition module, a processing module, and a determination module. The logging data of the coal-bearing strata is acquired, and the logging curves are fitted according to each parameter included in the logging data. Thus, different curve characteristics (i.e., the undulating characteristics of the curves) formed by the numerical magnitudes of the parameters in the logging data can be shown on the logging curves. Through the curve characteristics, the high and low of the numerical values of each parameter can be intuitively obtained. By combining the curve characteristics of multiple parameters, the lithology information of the coal-bearing strata can be determined. Among them, the lithology information of the coal-bearing strata includes mudstone information, carbonaceous mudstone information, and coal rock information.

[0103] For the implementation process of the functions and roles of each unit in the above device, please refer to the implementation process of the corresponding steps in the above method for details, which will not be elaborated here.

[0104] 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 embodiments described above are 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 may be 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 efforts.

[0105] Based on the same inventive concept, the embodiment of the present invention also provides a storage medium, on which a computer program is stored. When the program is executed by a processor, the steps of the confirmation method for the lithology information of the coal-bearing strata in any possible implementation manner described above are implemented.

[0106] Optionally, the storage medium may be a non-temporary computer-readable storage medium. For example, the non-temporary computer-readable storage medium may be ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device, etc.

[0107] Based on the same inventive concept, the embodiment of the present invention also provides a computer program product, including a computer program. When the program is executed by a processor, the steps of the confirmation method for the lithology information of the coal-bearing strata in any possible implementation manner described above are implemented.

[0108] Based on the same inventive concept, refer to Figure 6, an embodiment of the present invention further provides an electronic device 600, including a memory 602 (such as a non-volatile memory), a processor 604, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps of the method for confirming the lithological information of the coal-bearing strata in any of the above possible implementation manners, which is equivalent to the device for confirming the lithological information of the coal-bearing strata as described above. Of course, the processor can also be used to process other data or perform operations. The electronic device can be a device such as a PC, a server, or a terminal.

[0109] Generally, the electronic device 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.

[0110] It should be noted that the device for confirming the lithological information of the coal-bearing strata can be implemented by software. As a logically meaningful device, it is formed by the processor of the electronic device where it is located reading the computer program instructions stored in the non-volatile memory into the memory and running them.

[0111] The embodiments of the subject matter and the functional operations described in this specification can be implemented in the following: digital electronic circuits, tangibly embodied computer software or firmware, computer hardware including the structures disclosed in this specification and their structural equivalents, or a combination of one or more of them. The embodiments of the subject matter described in this specification can be implemented as one or more computer programs, that is, one or more modules in computer program instructions encoded on a tangible non-transitory program carrier to be executed by a data processing device or to control the operation of the data processing device. Alternatively or additionally, the program instructions can be encoded on an artificially generated propagated signal, such as a machine-generated electrical, optical, or electromagnetic signal, which is generated to encode and transmit information to a suitable receiver device for execution by the data processing device. The computer storage medium can be a machine-readable storage device, a machine-readable storage substrate, a random or serial access memory device, or a combination of one or more of them.

[0112] The processing and logical flows described in this specification can be executed by one or more programmable computers executing one or more computer programs to perform corresponding functions by operating on input data and generating outputs. The processing and logical flows can also be executed by dedicated logic circuits - such as FPGAs (Field Programmable Gate Arrays) or ASICs (Application Specific Integrated Circuits), and the device can also be implemented as a dedicated logic circuit.

[0113] Computers suitable for executing computer programs include, for example, general and / or special-purpose microprocessors, or any other type of central processing unit. Generally, the central processing unit will receive instructions and data from read-only memory and / or random access memory. The basic components of a computer include a central processing unit for implementing or executing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include one or more mass storage devices for storing data, such as magnetic disks, magneto-optical disks, or optical disks, etc., or the computer will be operably coupled to such mass storage devices to receive data from them or transfer data to them, or both. However, a computer is not necessarily required to have such devices. In addition, a computer may be embedded in another device, such as a mobile phone, a personal digital assistant (PDA), a mobile audio or video player, a game console, a global positioning system (GPS) receiver, or a portable storage device such as a universal serial bus (USB) flash drive, to name just a few examples.

[0114] Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices, such as semiconductor memory devices (e.g., EPROM, EEPROM, and flash memory devices), magnetic disks (e.g., internal hard disks or removable disks), magneto-optical disks, and CD-ROM and DVD-ROM disks. The processor and memory may be supplemented by, or incorporated in, special-purpose logic circuitry.

[0115] In this embodiment, different from the above embodiment where the entire core was taken from the Carboniferous-Permian interval of Qigu 16 Well, the Carboniferous-Permian interval of 3670 - 3760 m in Qigu 8 Well where there is no cored well was identified. As Figure 16 shown, two sets of coal seams were identified at 2703 - 2706 m and 2725 - 2730 m, with GR value of 25 - 31 API, AC value of 440 - 450 us / m, DEN value of 1.2 - 1.23 g / cm3, and RT value of 300 ohm.m; a mudstone interval developed at 3670 - 3678 m, with GR value of 115 API, AC value of 258 us / m, DEN value of 2.45 g / cm3, and RT value of 12 ohm.m; a carbonaceous mudstone interval at 3735 - 3740 m, with GR value of 95 API, AC value of 350 - 355 us / m, DEN value of 2.0 - 2.2 g / cm3, and RT value of 6 - 8 ohm.m.

[0116] There is a good corresponding relationship and discrimination degree in the cross-plot discrimination of the logging curves GR, AC, and DEN values of the Carboniferous-Permian, as Figure 17The AC-GR intersection diagram of Qigu-8 Well shown: Mudstone is in the range of [AC (200 - 300): GR (100 - 140)], coal is in the range of [AC (430 - 500): GR (25 - 75)], and carbonaceous mudstone is in the range of [AC (250 - 370): GR (75 - 125)]; as Figure 18 It can be seen from the DEN-GR intersection diagram of Qigu-8 Well shown: Mudstone is in the range of [DEN (2.3 - 2.8): GR (100 - 140)], coal is in the range of [DEN (1.2 - 1.6): GR (25 - 75)], and carbonaceous mudstone is in the range of [DEN (1.9 - 2.4): GR (75 - 125)].

[0117] The maceral data of the coal measures strata of Qigu-8 Well are plotted on the standard chart established in Example 1, showing a good degree of conformity. As Figure 19 Shown, the content of macerals in coal is [vitrinite (80 - 90%), exinite (0 - 20%), inertinite (0 - 10%)], the content of macerals in carbonaceous mudstone is [vitrinite (60 - 70%), exinite (0 - 10%), inertinite (30 - 40%)], and the content of macerals in mudstone is [vitrinite (30 - 60%), exinite (30 - 60%), inertinite (0 - 10%)].

[0118] Based on the accurate identification of the coal seam section, the acoustic time difference (AC) of the 3705m coal seam is 450 μs / m, and the density (DEN) is 1.23 g / cm3; the acoustic time difference (AC) of the 3730m coal seam is 440 μs / m, and the density (DEN) is 1.20 g / cm3. Based on the fitted formula for the industrial components of the coal seam, the industrial components of the coal seam in different sections can be calculated, as shown in Table 1. Both sections of the coal seam are of medium coal rank. The fixed carbon of the 3705m coal seam section is 82.1%, ash content is 6.79%, moisture content is 0.634%, and volatile matter is 10.47%. The fixed carbon of the 3730m coal seam section is 81.9%, ash content is 6.88%, moisture content is 0.63%, and volatile matter is 10.59%.

[0119] Table 1 Industrial Components of Coal Seam

[0120]

[0121] Combining the above comprehensive results, based on the coal gas content formula, the gas content of coal in different sections can be preliminarily estimated. As shown in Table 2, the gas contents of 3703m, 3705m, 3728m, and 3730m in Qigu-8 Well are 9.32%, 9.19%, 11.4%, and 8.75% respectively.

[0122] Table 2 Gas Content of Coal Seam

[0123]

[0124] Figure 20 Evaluation diagram of coal seam structure, showing the evaluation of coal seam structure.

[0125] Using this method, a total of 8 wells of "Paleozoic source rocks and Paleozoic reservoirs" in coal measures source rocks were deployed. Among them, the newly deployed well F1x1 in the Baitangkou area revealed thick coal measure strata. A total of 64 m of coal measure strata were identified in the Carboniferous-Permian interval, indicating that the buried hill oil and gas reservoirs of "Paleozoic source rocks and Paleozoic reservoirs" and "Paleozoic source rocks and Neozoic reservoirs" with coal measure strata as source rocks have great potential. Using this method, the exploration potential of buried hill oil and gas reservoirs with coal measure strata as source rocks can be effectively evaluated, and an effective evaluation method can be provided for the evaluation and development of deep coalbed methane.

[0126] Although this specification contains many specific implementation details, these should not be construed as limiting the scope of any invention or the scope of what is claimed, but rather are mainly used to describe the features of specific embodiments of a particular invention. Certain features described in multiple embodiments in this specification can also be implemented in combination in a single embodiment. On the other hand, the various features described in a single embodiment can also be implemented separately in multiple embodiments or in any suitable sub-combination. In addition, although features may operate in certain combinations as described above and are even initially claimed as such, one or more features from the claimed combination can in some cases be removed from the combination, and the claimed combination can be directed to a sub-combination or a variation of a sub-combination.

[0127] Similarly, although operations are depicted in the drawings in a particular order, this should not be construed as requiring that the operations be performed in the particular order shown or sequentially, or that all illustrated operations be performed, to achieve the desired result. In some cases, multitasking and parallel processing may be advantageous. In addition, the separation of the various system modules and components in the above embodiments should not be construed as required in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

[0128] Thus, specific embodiments of the subject matter have been described. Other embodiments are within the scope of the appended claims. In some cases, the acts recited in the claims can be performed in a different order and still achieve the desired result. In addition, the processes depicted in the drawings are not necessarily in the particular order or sequential order shown to achieve the desired result. In some implementations, multitasking and parallel processing may be advantageous.

[0129] It should be noted that in this text, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0130] The above are only specific embodiments of the present invention, enabling those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather will conform to the broadest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for confirming lithological information of coal measures strata, characterized in that, the method for confirming lithological information of coal measures strata includes: Obtaining well logging data of the coal measures strata; Fitting a well logging curve according to the well logging data; Determining the lithological information of the coal measures strata according to the curve characteristics in the well logging curve.

2. The method for confirming lithological information of coal measures strata according to claim 1, characterized in that, the step of determining the lithological information of the coal measures strata according to the curve characteristics in the well logging curve includes: Obtaining the curve characteristics of the well logging curve; If the curve characteristics match the preset characteristics, using the corresponding information of the preset characteristics as the lithological information of the coal measures strata.

3. The method for confirming lithological information of coal measures strata according to claim 2, characterized in that, the well logging data includes multiple well logging parameters, and the step of determining the lithological information of the coal measures strata according to the curve characteristics in the well logging curve further includes: Combining two well logging parameters among the multiple well logging parameters to form a well logging parameter set; Matching the well logging parameter set with a standard parameter set, and determining the lithological information of the coal measures strata according to the matching result.

4. The method for confirming lithological information of coal measures strata according to claim 3, characterized in that, after the step of determining the lithological information of the coal measures strata according to the curve characteristics in the well logging curve, it further includes: Performing X-ray diffraction analysis and maceral analysis on the coal measures strata to verify the accuracy of the lithological information.

5. The method for confirming lithological information of coal measures strata according to claim 4, characterized in that, the lithological information of the coal measures strata includes coal rock information, and after the step of performing X-ray diffraction analysis and maceral analysis on the coal measures strata to verify the accuracy of the lithological information, it further includes: Determining the industrial component information corresponding to the coal rock information according to the multiple well logging parameters; Determining the coal rank information corresponding to the coal rock information according to the industrial component information.

6. The method for confirming lithological information of coal measures strata according to claim 5, characterized in that, the method for confirming lithological information of coal measures strata further includes: Determining the structural information corresponding to the coal rock information according to multiple well logging parameters, where the structural information includes primary structure, fragmented structure and granular structure.

7. The method for confirming lithological information of coal measures strata according to claim 5, characterized in that, the method for confirming lithological information of coal measures strata further includes: Determining the gas content of coal seams corresponding to the coal rock information according to multiple well logging parameters.

8. A device for confirming lithological information of coal measures strata, characterized in that, the device for confirming lithological information of coal measures strata includes: An acquisition module for acquiring well logging data of the coal measures strata; A processing module for fitting a well logging curve according to the well logging data; A determination module for determining the lithological information of the coal measures strata according to the curve characteristics of the well logging curve.

9. A storage medium, on which a computer program is stored, characterized in that, When the described program is executed by a processor, it implements the steps of the method for confirming the lithological information of the coal-bearing strata described in any one of claims 1 to 7.

10. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein, when the processor executes the program, it implements the steps of the method for confirming the lithological information of the coal-bearing strata described in any one of claims 1 to 7.

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