Method and device for calculating total organic carbon content of shale

Abstract

The invention belongs to the technical field of petroleum and natural gas exploration and development, and discloses a shale total organic carbon content calculation method and device, and the method comprises the steps: carrying out mineral composition and organic matter density testing on a rock core of a shale evaluation reservoir; calculating the actual Young modulus of the shale evaluation reservoir; calculating the theoretical Young modulus of the shale evaluation reservoir; correcting the theoretical Young modulus by using the actual Young modulus, and calculating the proportion of the clay mineral content to the brittle mineral content; calculating the density of the clay minerals and the brittle minerals; and calculating the organic carbon content. The actual Young modulus is used for correcting the theoretical Young modulus, the influence relation of the single mineral Young modulus on the actual overall Young modulus is optimized, the TOC content can be calculated in the whole reservoir, the calculation process is simplified, the accuracy of the prediction result is improved, and the defect that a large amount of coring detection is needed in the traditional calculation process is overcome.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas exploration and development, and in particular relates to a method and a device for calculating the total organic carbon content of shale. Background Art

[0002] The accurate evaluation of geological sweet spots is the core indicator of oilfield exploration geological reserve potential and an important criterion for whether it has mining value. The core indicator for evaluating sweet spots is the quantitative calculation of the total organic carbon (TOC) content of the reservoir. The larger the value, the better the reservoir quality and the greater the exploration and development potential. At present, domestic and foreign scholars have conducted a lot of research on reservoir TOC content, mainly focusing on combining logging curve calculation with correlation algorithm calculation. The existing methods for predicting reservoir TOC content mainly include the following:

[0003] (1) The elastic parameter curve is calculated using the logging curve, and the TOC content curve is established using the TOC content obtained from coring. The elastic parameter curve is combined with the TOC content curve, and the relationship between the two is obtained through seismic inversion calculation. The well logging data, VSP logging results and 3D seismic data are used to quantitatively predict the planar distribution of TOC content and the distribution range of organic carbon content.

[0004] (2) A mineral rock physics model for TOC optimization estimation was established using laboratory-measured X-ray diffraction data, organic carbon density, logging density curves and other data. The accurate TOC distribution on the well was obtained through an iterative optimization method. A TOC quantitative plate was established using the measured TOC data and an equivalent medium model, and the TOC-sensitive elastic parameters were determined. Finally, prestack elastic parameter inversion was performed on the seismic reflection traces processed in the OVT domain. Statistical fitting was used to achieve the purpose of quantitatively predicting the spatial distribution of TOC content by combining well and seismic data, thus solving the technical problem of low prediction results of TOC content.

[0005] (3) The principal component analysis method was used to preprocess the data, and two TOC content prediction models were established based on the BP neural network and the gradient boosting decision tree (GBDT) method, which were compared with the traditional TOC content prediction method. The TOC content of the reservoir was predicted using the results of machine learning prediction.

[0006] Method (1) combines the target value with the main influencing parameters to solve and predict, but the disadvantage of this method is that it relies on field test data. Due to the limitation of the accuracy of the test instrument, the calculation result has a large error and is difficult to accurately evaluate. Method (2) is also too dependent on field data, but its advantage is that the data it gives for a specific reservoir will be very correct, but there is too much preliminary preparation work. Method (3) starts from the current mainstream algorithm. Neural networks have a strong leading role in big data prediction. Method (3) starts from selecting highly correlated data and performs specific mathematical processing on the target data to predict it, but similarly, too much data is needed to support the development of its algorithm. Therefore, it is necessary to propose a TOC content calculation method with strong universality, which should be combined with field reality and theory at the same time. The calculation results are more scientific and generally practical, providing important guidance for the economic development of unconventional resources. Summary of the invention

[0007] In order to overcome the defects of the above-mentioned prior art, the purpose of the present invention is to provide a method and device for calculating the total organic carbon content of shale based on the mechanical properties of rock, and to calculate the TOC content of the reservoir by combining the actual core data on site with the theoretical data. First, coring is carried out in the target reservoir section for evaluation, the mineral composition of the core is tested, and the rock mechanical parameter Young's modulus is calculated. Then, the minerals in the shale are divided into brittle minerals and clay minerals, the theoretical Young's modulus is compared with the actual Young's modulus, and data processing is performed to predict the clay layer content of the reservoir. Finally, the TOC content of the reservoir is obtained, so as to achieve the purpose of quantitative evaluation of the reservoir TOC.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A method for calculating the total organic carbon content of shale, characterized by comprising:

[0010] Conduct mineral composition and organic matter density tests on cores of shale evaluation reservoirs;

[0011] Calculate the actual Young's modulus of the shale evaluation reservoir based on the P-wave and S-wave corresponding to the coring location;

[0012] The theoretical Young's modulus of shale reservoir evaluation is calculated using the mechanical property parameters of different mineral components;

[0013] The actual Young's modulus of the shale evaluation reservoir is used to correct the theoretical Young's modulus of the shale evaluation reservoir, and the corrected Young's modulus of the shale evaluation reservoir is obtained, and the proportion of clay mineral content and brittle mineral content in each layer of the shale evaluation reservoir is calculated;

[0014] Calculate the density of clay minerals and brittle minerals in shale evaluation reservoirs;

[0015] The organic carbon content of each layer of the shale evaluation reservoir is calculated based on the density of clay minerals and brittle minerals in the shale evaluation reservoir and the proportion of clay mineral content and brittle mineral content in each layer of the shale evaluation reservoir.

[0016] Furthermore, the actual Young's modulus of the shale evaluation reservoir is calculated based on the longitudinal and transverse waves corresponding to the coring position, and the calculation formula is:

[0017]

[0018] Among them, E v is the actual Young's modulus of the shale reservoir, MPa; ρ is the density of the core, kg / m 3 ; V p is the longitudinal wave velocity corresponding to the coring position, m / s; V s is the shear wave velocity corresponding to the coring position, m / s.

[0019] Furthermore, the theoretical Young's modulus of the shale evaluation reservoir is calculated using the mechanical property parameters of different mineral components. The calculation formula is:

[0020]

[0021] Among them, E e is the theoretical Young's modulus of shale reservoir evaluation, MPa; n is the number of mineral components, i=1,2...n; E i is the Young's modulus of various brittle single minerals in the mineral composition, MPa; E n is the Young's modulus of clay minerals in the mineral composition, MPa; k c is the proportion of brittle minerals in the shale reservoir, %; k n The proportion of clay minerals in the shale evaluation reservoir, %.

[0022] Furthermore, the actual Young's modulus of the shale evaluation reservoir is used to correct the theoretical Young's modulus of the shale evaluation reservoir to obtain the corrected Young's modulus of the shale evaluation reservoir, and the clay mineral content and brittle mineral content ratio of each layer of the shale evaluation reservoir are calculated, including:

[0023] Clay mineral content ratio of shale evaluation reservoir k n The proportion of brittle minerals c The calculation formula is as follows:

[0024]

[0025]

[0026]

[0027] kc +k n =1

[0028] in, Young's modulus of brittle minerals in the reservoir for the corrected shale evaluation, MPa; Young's modulus of clay minerals in the reservoir for the corrected shale evaluation, MPa; Young's modulus of the reservoir for the corrected shale evaluation, MPa;

[0029] The clay mineral content ratio k of shale evaluation reservoir layer A n The proportion of brittle minerals k c The calculation formula is as follows, where layer A is any layer of the shale evaluation reservoir:

[0030]

[0031]

[0032]

[0033]

[0034] k c1 +k n1 =1

[0035] Among them, E v1 Actual Young's modulus of reservoir layer A for shale evaluation, MPa; E e1 Theoretical Young's modulus of reservoir interval A for shale evaluation, MPa; The Young's modulus of brittle minerals in reservoir interval A was evaluated for the corrected shale; is the Young's modulus of clay minerals in the modified shale reservoir section A; ρ is the density of the core, kg / m 3 ; V p1 P-wave velocity of reservoir segment A for shale evaluation, m / s; V s1 The shear wave velocity of the reservoir layer A for shale evaluation, m / s; k c1 is the proportion of brittle mineral content in shale reservoir layer A, %; k n1 The clay mineral content percentage of shale evaluation reservoir layer A is %.

[0036] Furthermore, the density of clay minerals and brittle minerals in the shale evaluation reservoir is calculated using the following formula:

[0037]

[0038]

[0039] Among them, ρc is the average density of brittle minerals in shale reservoir evaluation, kg / m 3 ; n is the number of mineral components, i=1,2...n-1; ρ i It is the density of various brittle single minerals in the mineral composition, kg / m 3 ρ n is the average density of clay minerals in shale reservoir evaluation, kg / m 3 ; j is the number of clays inside the clay mineral, pieces; r = 1, 2...j; ρ j is the density of each clay.

[0040] Furthermore, the organic carbon content of each layer of the shale evaluation reservoir is calculated based on the density of clay minerals and brittle minerals in the shale evaluation reservoir and the proportion of clay mineral content and brittle mineral content in each layer of the shale evaluation reservoir, including:

[0041] Calculate the organic matter content k of shale evaluation reservoir layer A n1 :

[0042] ρ d =ρ y ρ n2 +ρ n k n3 +ρ c k c1

[0043] k n1 =k n2 +k n3

[0044] Among them, ρ d is the density of the well logging density curve at the corresponding point of the core, kg / m 3 ρ y is the density of organic matter, kg / m 3 ;k n1 is the clay mineral content ratio of shale evaluation reservoir layer A, %; k n2 and k n3 They are respectively the proportion of organic matter content and inorganic matter content in clay minerals of shale evaluation reservoir interval A, %;

[0045] Calculate the organic carbon content T of shale evaluation reservoir layer A:

[0046]

[0047] Wherein, T is the organic carbon content of shale reservoir layer A, %; V y and V z are the volume of organic matter in shale evaluation reservoir layer A and the volume of shale evaluation reservoir layer A, m 3.

[0048] Furthermore, before testing the mineral composition and organic matter density of the core of the shale evaluation reservoir, the following are included:

[0049] The core is made into rock samples, and the rock samples are dried to constant weight.

[0050] In a second aspect, the present invention discloses a device for calculating the total organic carbon content of shale, comprising:

[0051] Mineral composition and organic matter density test module, used to test the mineral composition and organic matter density of the core of the shale evaluation reservoir;

[0052] The actual Young's modulus calculation module is used to calculate the actual Young's modulus of the shale evaluation reservoir based on the longitudinal wave and the transverse wave corresponding to the coring position of the core;

[0053] Theoretical Young's modulus calculation module, used to calculate the theoretical Young's modulus of shale evaluation reservoir using mechanical property parameters of different mineral components;

[0054] The mineral content ratio calculation module is used to correct the theoretical Young's modulus of the shale evaluation reservoir using the actual Young's modulus of the shale evaluation reservoir, obtain the corrected Young's modulus of the shale evaluation reservoir, and calculate the clay mineral content and brittle mineral content ratio of each layer of the shale evaluation reservoir;

[0055] Density calculation module, used to calculate the density of clay minerals and brittle minerals in shale evaluation reservoirs;

[0056] The organic carbon content calculation module is used to calculate the organic carbon content of each layer of the shale evaluation reservoir based on the density of clay minerals and brittle minerals in the shale evaluation reservoir and the proportion of clay mineral content and brittle mineral content in each layer of the shale evaluation reservoir.

[0057] In a third aspect, the present invention discloses an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of the above-mentioned method for calculating the total organic carbon content of shale are implemented.

[0058] In a fourth aspect, the present invention discloses a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned steps of calculating the total organic carbon content of shale.

[0059] Technical effects and advantages of the present invention:

[0060] The present invention utilizes actual Young's modulus to correct theoretical Young's modulus, optimizes the influence relationship of single mineral Young's modulus on actual overall Young's modulus, and defines a new method for calculating reservoir TOC content in combination with density curve. The TOC content of the entire reservoir can be calculated, which simplifies the calculation process, improves the accuracy of prediction results, and makes up for the disadvantage that the traditional calculation process requires a large number of coring tests. It plays an important guiding role in effectively reducing exploration and development costs and evaluating reservoir TOC content, and has broad application prospects.

[0061] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 This is a flow chart of a method for calculating the total organic carbon content of shale according to the present invention;

[0063] Figure 2 This is a structural diagram of a shale total organic carbon content calculation device according to the present invention. DETAILED DESCRIPTION

[0064] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0065] like Figure 1 As shown, the present invention provides a method for calculating the total organic carbon content of shale, comprising:

[0066] Conducting mineral composition and organic matter density tests on cores of shale evaluation reservoirs, wherein the mineral composition includes brittle minerals and clay minerals, and the brittle minerals include a variety of brittle single minerals;

[0067] Calculating the actual Young's modulus of the shale evaluation reservoir based on the longitudinal wave and the transverse wave corresponding to the coring position;

[0068] Calculating the theoretical Young's modulus of the shale evaluation reservoir using the mechanical property parameters of the different mineral components;

[0069] Using the actual Young's modulus of the shale evaluation reservoir to correct the theoretical Young's modulus of the shale evaluation reservoir, obtain the corrected Young's modulus of the shale evaluation reservoir, and calculate the proportion of clay mineral content and brittle mineral content in each layer of the shale evaluation reservoir;

[0070] Calculate the density of clay minerals and brittle minerals in shale evaluation reservoirs;

[0071] The organic carbon content of each layer of the shale evaluation reservoir is calculated based on the density of clay minerals and brittle minerals in the shale evaluation reservoir and the proportion of clay mineral content and brittle mineral content in each layer of the shale evaluation reservoir.

[0072] In some embodiments of the present invention, the actual Young's modulus of the shale evaluation reservoir is calculated based on the longitudinal wave and the shear wave corresponding to the coring position, and the calculation formula is:

[0073]

[0074] Among them, E v is the actual Young's modulus of the shale reservoir, MPa; ρ is the density of the core, kg / m 3 ; V p is the longitudinal wave velocity corresponding to the coring position, m / s; V s is the shear wave velocity corresponding to the coring position, m / s.

[0075] In some embodiments of the present invention, the theoretical Young's modulus of the shale evaluation reservoir is calculated using the mechanical property parameters of different mineral components, and the calculation formula is:

[0076]

[0077] Among them, E e is the theoretical Young's modulus of shale reservoir evaluation, MPa; n is the number of mineral components, i=1,2...n; E i is the Young's modulus of various brittle single minerals in the mineral composition, MPa; E n is the Young's modulus of clay minerals in the mineral composition, MPa; k c is the proportion of brittle minerals in the shale reservoir, %; k n The proportion of clay minerals in the shale evaluation reservoir, %.

[0078] In some embodiments of the present invention, the actual Young's modulus of the shale evaluation reservoir is used to correct the theoretical Young's modulus of the shale evaluation reservoir to obtain the corrected Young's modulus of the shale evaluation reservoir, and the clay mineral content and brittle mineral content ratio of each layer of the shale evaluation reservoir are calculated, including:

[0079] Clay mineral content ratio of shale evaluation reservoir k n The proportion of brittle minerals c The calculation formula is as follows:

[0080]

[0081]

[0082]

[0083] k c +k n =1

[0084] in, Young's modulus of brittle minerals in the reservoir for the corrected shale evaluation, MPa; Young's modulus of clay minerals in the reservoir for the corrected shale evaluation, MPa; Young's modulus of the modified shale evaluation reservoir, MPa.

[0085] The clay mineral content ratio k of shale evaluation reservoir layer A n The proportion of brittle minerals k c The calculation formula is as follows, where layer A is any layer of the shale evaluation reservoir:

[0086]

[0087]

[0088]

[0089]

[0090] k c1 +k n1 =1

[0091] Among them, E v1 Actual Young's modulus of reservoir layer A for shale evaluation, MPa; E e1 Theoretical Young's modulus of reservoir interval A for shale evaluation, MPa; Evaluating the Young's modulus of brittle minerals in reservoir interval A for the revised shale; is the Young's modulus of clay minerals in the shale evaluation reservoir layer A after correction; ρ is the density of the core, kg / m 3 ; V p1 P-wave velocity of reservoir segment A for shale evaluation, m / s; V s1 The shear wave velocity of the reservoir layer A for shale evaluation, m / s; k c1 is the proportion of brittle mineral content in shale reservoir layer A, %; k n1 The clay mineral content percentage of shale evaluation reservoir layer A is %.

[0092] In some embodiments of the present invention, the density of clay minerals and brittle minerals in the shale evaluation reservoir is calculated using the following formula:

[0093]

[0094]

[0095] Among them, ρ c is the average density of brittle minerals in shale reservoir evaluation, kg / m 3 ; n is the number of mineral components, i=1,2...n-1; ρ i It is the density of various brittle single minerals in the mineral composition, kg / m 3 ρ n is the average density of clay minerals in shale reservoir evaluation, kg / m 3 ; j is the number of clays inside the clay mineral, pieces; r = 1, 2...j; ρ j is the density of each clay.

[0096] In some embodiments of the present invention, the organic carbon content of each layer of the shale evaluation reservoir is calculated based on the density of clay minerals and brittle minerals in the shale evaluation reservoir and the ratio of clay mineral content to brittle mineral content in each layer of the shale evaluation reservoir, including:

[0097] Calculate the organic matter content k of shale evaluation reservoir layer A n2 :

[0098] ρ d =ρ y ρ n2 +ρ n k n3 +ρ c k c1

[0099] k n1 =k n2 +k n3

[0100] Among them, ρ d is the density of the logging density curve of the shale evaluation reservoir layer A, kg / m 3 ρ y is the density of organic matter, kg / m 3 ;k n1 is the clay mineral content ratio of shale evaluation reservoir layer A, %; k n2 and k n3 They are respectively the proportion of organic matter content and inorganic matter content in clay minerals of shale evaluation reservoir interval A, %;

[0101] Calculate the organic carbon content T of shale evaluation reservoir layer A:

[0102]

[0103] Wherein, T is the organic carbon content of shale reservoir layer A, %; V y and V z are the volume of organic matter in shale evaluation reservoir layer A and the volume of shale evaluation reservoir layer A, m 3 .

[0104] In some embodiments of the present invention, before using an X-ray diffractometer to test the mineral composition and organic matter density of a core of a shale evaluation reservoir, the method includes:

[0105] The core was made into rock samples, and the rock samples were dried at 100° to constant weight.

[0106] Second, as Figure 2 As shown, the present invention discloses a device for calculating the total organic carbon content of shale, comprising:

[0107] Mineral composition and organic matter density test module, used to test the mineral composition and organic matter density of the core of the shale evaluation reservoir using an X-ray diffractometer;

[0108] The actual Young's modulus calculation module is used to calculate the actual Young's modulus of the shale evaluation reservoir based on the longitudinal wave and the transverse wave corresponding to the coring position of the core;

[0109] Theoretical Young's modulus calculation module, used to calculate the theoretical Young's modulus of shale evaluation reservoir using the mechanical parameter properties of different mineral components;

[0110] The mineral content ratio calculation module is used to correct the theoretical Young's modulus of the shale evaluation reservoir using the actual Young's modulus of the shale evaluation reservoir, obtain the corrected Young's modulus of the shale evaluation reservoir, and calculate the clay mineral content and brittle mineral content ratio of each layer of the shale evaluation reservoir;

[0111] Density calculation module, used to calculate the density of clay organic minerals and brittle minerals in shale evaluation reservoirs;

[0112] The organic carbon content calculation module is used to calculate the organic carbon content of each layer of the shale evaluation reservoir based on the density of clay minerals and brittle minerals in the shale evaluation reservoir and the proportion of clay mineral content and brittle mineral content in each layer of the shale evaluation reservoir.

[0113] In a third aspect, the present invention discloses an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of the above-mentioned method for calculating the total organic carbon content of shale are implemented.

[0114] In a fourth aspect, the present invention discloses a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned steps of calculating the total organic carbon content of shale.

[0115] In order to better illustrate the present solution, the following embodiments are also provided.

[0116] Example

[0117] Step 1: Take a shale gas well core with a core depth of 1500-1700m, and make a standard rock sample with a diameter of 2.5cm and a length of 5cm. The rock sample is numbered S1 and placed in a 100℃ oven to dry to constant weight. The mineral composition and organic matter density of the dried rock sample are tested by X-ray diffractometer. The test results are shown in Table 1.

[0118] Table 1 Basic parameters of core samples

[0119]

[0120] Step 2: According to the coring position, obtain the longitudinal and transverse waves of the corresponding interval from the well logging diagram to obtain the longitudinal wave velocity V p is 6423m / s, and the shear wave velocity V s The velocity is 5078 m / s, and the density of the core sample is 2.43 g / cm 3 , using the formula Calculate the actual Young's modulus E v The value is 83527.97MPa.

[0121] Step 3: Calculate the theoretical Young's modulus of the shale evaluation reservoir using the mechanical property parameters of different mineral components. The mechanical property parameters of different mineral components are shown in Table 2.

[0122] Table 2 Mineral mechanical properties of different mineral components

[0123] Mineral Name Young's modulus (MPa) <![CDATA[Density (g / cm 3 )]]> quartz 95942.54 2.65 dolomite 105309.01 2.67 Calcite 78010.81 2.71 Feldspar 64838.72 2.59 clay 21914.15 2.12

[0124] According to the mechanical property parameters of different mineral components in Table 2, the average Young's modulus of brittle minerals (quartz, dolomite, calcite, feldspar) is 86025.27 MPa, and the average Young's modulus of clay organic minerals (clay) is E n is 21914.15MPa, using the formula Obtain the theoretical Young's modulus E of the shale evaluation reservoir e It is 59278.11MPa.

[0125] Step 4: Use the formula k c +k n =1Calculate the Young's modulus of brittle minerals in shale reservoir after correction The Young's modulus of clay minerals in shale reservoir after correction is 121217.03MPa. It is 30878.93MPa.

[0126] The acoustic wave computational mechanical properties of the shale reservoir where the S1 sample is located can be used to calculate the corresponding brittle mineral proportion and clay mineral proportion. For other areas (layer segment A) in the reservoir, the P-wave velocity V p1 is 6523m / s, and the shear wave velocity V s1 is 4978m / s, using the formula:

[0127]

[0128]

[0129]

[0130]

[0131] k c1 +k n1 =1

[0132] The actual Young's modulus E of layer segment A is obtained v1 is 96672.45MPa, and the proportion of brittle minerals in layer A can be further obtained. c1 The clay mineral ratio of layer A is 72.8%. n1 It is 27.2%.

[0133] Step 5: Use the formula and The average density of brittle minerals and clay minerals in the shale evaluation reservoir is calculated respectively, and the average density of brittle minerals in the shale evaluation reservoir can be obtained: c 2.66g / cm 3 , the average density of clay minerals in shale evaluation reservoirs ρ n 2.12g / cm 3 .

[0134] Step 6: Read the well logging density curve of the corresponding point of the S1 sample and obtain its density ρ d 2.35g / cm 3 , so using the formula ρ d =ρ y ρ n2 +ρ n k n3 +ρ c k c1 , k n1 =k n2 +k n3 Calculate the proportion of organic matter in clay minerals in shale evaluation reservoir layer A n2 , we get kn2 The value of k is 11.6%, n3 is 15.6%, so, using the formula The organic carbon content T of the shale evaluation reservoir layer section A was calculated, and it was found that the organic carbon content T of the shale evaluation reservoir layer section A was 3.5%.

[0135] In summary, the present invention uses actual Young's modulus to correct theoretical Young's modulus, optimizes the influence of single mineral Young's modulus on actual overall Young's modulus, and defines a new method for calculating reservoir TOC content in combination with density curve. TOC content of the entire reservoir can be calculated, which simplifies the calculation process, improves the accuracy of prediction results, and makes up for the disadvantage that the traditional calculation process requires a large number of coring tests. It plays an important guiding role in effectively reducing exploration and development costs and evaluating reservoir TOC content, and has broad application prospects.

[0136] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for calculating the total organic carbon content of shale, characterized in that: include: Conduct mineral composition and organic matter density tests on cores of shale evaluation reservoirs; Calculating the actual Young's modulus of the shale evaluation reservoir based on the longitudinal wave and the transverse wave corresponding to the coring position; Calculating the theoretical Young's modulus of the shale evaluation reservoir using the mechanical property parameters of the different mineral components; Using the actual Young's modulus of the shale evaluation reservoir to correct the theoretical Young's modulus of the shale evaluation reservoir, obtain the corrected Young's modulus of the shale evaluation reservoir, and calculate the proportion of clay mineral content and brittle mineral content in each layer of the shale evaluation reservoir; Calculate the density of clay minerals and brittle minerals in shale evaluation reservoirs; The organic carbon content of each layer of the shale evaluation reservoir is calculated based on the density of clay minerals and brittle minerals in the shale evaluation reservoir and the proportion of clay mineral content and brittle mineral content in each layer of the shale evaluation reservoir.

2. The method for calculating the total organic carbon content of shale according to claim 1, characterized in that: The actual Young's modulus of the shale evaluation reservoir is calculated based on the longitudinal wave and the transverse wave corresponding to the coring position, and the calculation formula is: Among them, E v is the actual Young's modulus of the shale reservoir, MPa; ρ is the density of the core, kg / m 3 ; V p is the longitudinal wave velocity corresponding to the coring position, m / s; V s is the shear wave velocity corresponding to the coring position, m / s.

3. The method for calculating the total organic carbon content of shale according to claim 2, characterized in that: The theoretical Young's modulus of the shale evaluation reservoir is calculated by using the mechanical property parameters of different mineral components, and the calculation formula is: Among them, E e is the theoretical Young's modulus of the shale reservoir, MPa; n is the number of types of the mineral components, i=1,2...n; E i is the Young's modulus of various brittle single minerals in the mineral composition, MPa; E n is the Young's modulus of clay mineral in the mineral component, MPa; k c is the proportion of brittle minerals in the shale reservoir, %; k n The proportion of clay minerals in the shale evaluation reservoir, %.

4. A method for calculating the total organic carbon content of shale according to claim 3, characterized in that: The method of using the actual Young's modulus of the shale evaluation reservoir to correct the theoretical Young's modulus of the shale evaluation reservoir to obtain the corrected Young's modulus of the shale evaluation reservoir, and calculating the proportion of clay mineral content and brittle mineral content in each layer of the shale evaluation reservoir, includes: Clay mineral content ratio of shale evaluation reservoir k n The proportion of brittle minerals c The calculation formula is as follows: k+k=1 cn in, Young's modulus of brittle minerals in the reservoir for the corrected shale evaluation, MPa; Young's modulus of clay minerals in the reservoir for the corrected shale evaluation, MPa; Young's modulus of the reservoir for the corrected shale evaluation, MPa; The clay mineral content ratio k of shale evaluation reservoir layer A n The proportion of brittle minerals c The calculation formula is as follows, where layer A is any layer of the shale evaluation reservoir: k c1 +k n1 =1 Among them, E v1 Actual Young's modulus of reservoir layer A for the shale evaluation, MPa; E e1 Theoretical Young's modulus of reservoir interval A evaluated for the shale, MPa; Evaluating the Young's modulus of brittle minerals in reservoir interval A for the revised shale; is the modified Young's modulus of clay minerals in the shale evaluation reservoir layer A; ρ is the density of the core, kg / m 3 ; V p1 P-wave velocity of reservoir segment A for shale evaluation, m / s; V s1 The shear wave velocity of the reservoir layer A for the shale evaluation, m / s; k c1 k is the proportion of brittle mineral content in the reservoir layer A of the shale evaluation, %; n1 is the clay mineral content percentage of the shale evaluation reservoir layer A, %.

5. A method for calculating the total organic carbon content of shale according to claim 4, characterized in that: The calculation formula for calculating the density of clay minerals and brittle minerals in the shale evaluation reservoir is: Among them, ρ c is the average density of brittle minerals in shale reservoir evaluation, kg / m 3 ; n is the number of types of the mineral components, i = 1, 2...n-1; ρ i is the density of various brittle single minerals in the mineral composition, kg / m 3 ρ n is the average density of clay minerals in shale reservoir evaluation, kg / m 3 ; j is the number of clays inside the clay mineral, pieces; r = 1, 2...j; ρ j is the density of each clay.

6. A method for calculating the total organic carbon content of shale according to claim 5, characterized in that: The method of calculating the organic carbon content of each layer of the shale evaluation reservoir based on the density of clay minerals and brittle minerals in the shale evaluation reservoir and the proportion of clay mineral content to brittle mineral content in each layer of the shale evaluation reservoir includes: Calculate the organic matter content k of shale evaluation reservoir layer A n1 : r d =ρ y r n2 +r n k n3 +r c k c1 k n1 =k n2 +k n3 Among them, ρ d is the density of the well logging density curve at the corresponding point of the core, kg / m 3 ρ y is the organic matter density, kg / m 3 ;k n1 is the clay mineral content ratio of shale evaluation reservoir layer A, %; k n2 and k n3 They are respectively the proportion of organic matter content and inorganic matter content in clay minerals of shale evaluation reservoir interval A, %; Calculate the organic carbon content T of shale evaluation reservoir layer A: Wherein, T is the organic carbon content of shale reservoir layer A, %; V y and V z are the volume of organic matter in shale evaluation reservoir layer A and the volume of shale evaluation reservoir layer A, m 3 .

7. A method for calculating the total organic carbon content of shale according to any one of claims 1 to 6, characterized in that: Before conducting mineral composition and organic matter density tests on the core of the shale evaluation reservoir, the following steps are included: The core is made into a rock sample, and the rock sample is dried to a constant weight.

8. A device for calculating the total organic carbon content of shale, characterized in that: include: Mineral composition and organic matter density test module, used to test the mineral composition and organic matter density of the core of the shale evaluation reservoir; An actual Young's modulus calculation module, used to calculate the actual Young's modulus of the shale evaluation reservoir based on the longitudinal wave and the transverse wave corresponding to the coring position of the core; A theoretical Young's modulus calculation module is used to calculate the theoretical Young's modulus of the shale evaluation reservoir using the mechanical property parameters of the different mineral components; A mineral content ratio calculation module is used to correct the theoretical Young's modulus of the shale evaluation reservoir using the actual Young's modulus of the shale evaluation reservoir to obtain the corrected Young's modulus of the shale evaluation reservoir, and calculate the clay mineral content and brittle mineral content ratio of each layer of the shale evaluation reservoir; A density calculation module, used to calculate the density of clay minerals and brittle minerals in the shale evaluation reservoir; The organic carbon content calculation module is used to calculate the organic carbon content of each layer of the shale evaluation reservoir based on the density of clay minerals and brittle minerals in the shale evaluation reservoir and the proportion of clay mineral content and brittle mineral content in each layer of the shale evaluation reservoir.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps of the method for calculating the total organic carbon content of shale described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of calculating the total organic carbon content of shale as described in any one of claims 1 to 7 are implemented.

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