Method for determining storage conditions of highly over-mature shale gas, terminal and storage medium

Abstract

The present application provides a method, terminal and storage medium for determining the preservation conditions of highly over-mature shale gas. The method includes: calculating the actual shale reservoir gas content parameters and theoretical shale reservoir gas content parameters of the target shale sample; calculating the first content ratio of the target shale sample based on the actual shale reservoir gas content parameters, the first content ratio being the ratio of the actual shale gas percentage content; calculating the second content ratio of the target shale sample based on the theoretical reservoir gas content parameters, the second content ratio being the ratio of the theoretical shale gas percentage content; calculating the standardized content ratio of the target shale sample using the first content ratio and the second content ratio of the target shale sample; determining the shale gas preservation condition type of the target shale sample according to the standardized content ratio of the target shale sample, the shale gas preservation condition type including normal and abnormal. The present application can improve the accuracy and pertinence of determining shale gas preservation conditions.

Description

Technical Field

[0001] The present application relates to the field of natural gas exploration, and in particular to a method for determining the preservation conditions of highly over-mature shale gas, a terminal and a storage medium. Background Art

[0002] High over-mature shales usually experience a series of complex burial histories, hydrocarbon generation histories, and tectonic evolution histories, and their gas content is also significantly different from that of medium and low-mature shales. High over-mature shale gas usually has the characteristics of high nitrogen and low hydrocarbons, and the nitrogen content can be used as an effective indicator parameter for evaluating the preservation conditions of high over-mature shale gas. In terms of plane, my country's high over-mature shale gas is mainly distributed in the southern region; in terms of stratigraphic position, the Silurian and Cambrian strata are important objects for the development of high over-mature shale gas in my country, and are also the main strata for achieving breakthroughs in exploration and development, such as the Lower Silurian Longmaxi Formation and the Lower Cambrian Niutitang Formation. In addition, deep shale gas in the same area has a higher degree of thermal evolution than medium-deep and shallow shale gas, and high over-mature shale gas can be developed beyond a certain depth range. It is not difficult to see that high over-mature shale gas has a wide distribution range and good resource potential. At the same time, because high over-mature shale gas has undergone complex geological evolution, its preservation conditions have become a key factor restricting the enrichment and accumulation of shale gas. Therefore, scientifically and rationally evaluating the high-overmature preservation conditions is of great significance for improving the understanding of the distribution and enrichment laws of shale gas, enriching the basic geological theory of shale gas, and improving the results of exploration practice.

[0003] At present, the evaluation of shale gas preservation conditions mainly focuses on the analysis of geological factors that affect shale gas enrichment and accumulation. The evaluation contents involved include shale reservoir thickness, thermal evolution degree, burial depth, formation inclination, top and bottom plate lithology and thickness, hydrogeology, structural conditions and many other aspects. The existing shale gas preservation condition methods used in the evaluation of the preservation conditions of highly mature shale gas mainly have the following problems: (1) The existing methods are mainly applicable to the general situation of shale gas preservation condition evaluation, and do not take into account the particularity of highly mature shale gas enrichment and accumulation, and are not targeted enough for the evaluation of the preservation conditions of highly mature shale gas; (2) The existing methods involve some non-quantitative geological parameters, which are difficult to achieve complete quantitative evaluation in the actual evaluation process, and usually require a certain amount of human subjective judgment; (3) The existing methods involve too many evaluation parameters and evaluation systems, and the corresponding amount of evaluation data required is large, which requires a lot of time and financial costs; (4) The existing methods mainly focus on the evaluation of macroscopic geological conditions related to shale gas preservation, but pay insufficient attention to the response of shale gas content to preservation conditions, especially the understanding of shale gas preservation conditions reflected by the changes in gas components has not been fully evaluated and applied; (5) Since the existing methods cannot fully achieve quantitative evaluation, they have certain limitations in terms of method automation, intelligence, informationization and computerization, which greatly reduces the efficiency of shale gas preservation condition evaluation. Summary of the invention

[0004] The present application provides a method, terminal and storage medium for determining the preservation conditions of highly over-mature shale gas, so as to solve the problem that the prior art cannot accurately determine the preservation conditions of highly over-mature shale gas.

[0005] In a first aspect, the present application provides a method for determining the preservation conditions of highly over-mature shale gas, comprising:

[0006] Calculate actual shale reservoir gas content parameters and theoretical shale reservoir gas content parameters of target shale samples;

[0007] Calculating a first content ratio of the target shale sample based on an actual shale reservoir gas-bearing parameter of the target shale sample, wherein the first content ratio is a ratio of actual shale gas percentage content;

[0008] Based on the theoretical reservoir gas content parameter of the target shale sample, calculating a second content ratio of the target shale sample, wherein the second content ratio is a ratio of theoretical shale gas percentage content;

[0009] Calculating a standardized content ratio of the target shale sample using the first content ratio and the second content ratio of the target shale sample;

[0010] According to the standardized content ratio of the target shale sample, the shale gas preservation condition type of the target shale sample is determined, and the shale gas preservation condition type includes normal and abnormal.

[0011] In a second aspect, the present application provides a terminal, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the method described in the first aspect or any possible implementation of the first aspect are implemented.

[0012] In a third aspect, the present application provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the steps of the method described in the first aspect or any possible implementation of the first aspect.

[0013] The present application provides a method, terminal and storage medium for determining preservation conditions of highly overmature shale gas, which calculates actual shale reservoir gas content parameters and theoretical shale reservoir gas content parameters of a target shale sample; based on the actual shale reservoir gas content parameters of the target shale sample, calculates a first content ratio of the target shale sample, the first content ratio being the ratio of actual shale gas percentage content; based on the theoretical reservoir gas content parameters of the target shale sample, calculates a second content ratio of the target shale sample, the second content ratio being the ratio of theoretical shale gas percentage content; using the first content ratio and the second content ratio of the target shale sample, calculates a standardized content ratio of the target shale sample; and according to the standardized content ratio of the target shale sample, determines the shale gas preservation condition type of the target shale sample, the shale gas preservation condition types including normal and abnormal. The present application calculates a standardized content ratio by using the first content ratio and the second content ratio, which not only improves the accuracy and specificity of determining shale gas preservation conditions, but also avoids analyzing complex shale gas geological factors and parameters. It is only necessary to consider the gas composition of shale gas to realize the judgment of the preservation conditions of highly mature shale gas, making the entire judgment process low-cost and simple and feasible. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0015] Figure 1 It is a flow chart for implementing the method for determining the preservation conditions of highly over-mature shale gas provided in the embodiment of the present application;

[0016] Figure 2It is a structural schematic diagram of a device for determining storage conditions of highly over-mature shale gas provided in an embodiment of the present application;

[0017] Figure 3 It is a schematic diagram of a terminal provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0019] In order to make the purpose, technical solutions and advantages of the present application clearer, specific embodiments will be described below in conjunction with the accompanying drawings.

[0020] In order to determine the preservation conditions of highly mature shale gas, the embodiment of the present application innovatively proposes a standardized content ratio as an index parameter based on the difference in the percentage content of the measured and theoretical shale gas components, which is used to determine the type of preservation conditions of highly mature shale gas. This parameter is constructed based on the standardized total gas content ratio and the standardized adsorbed gas content ratio. In the embodiment of the present application, the shale gas components include N 2 and CH 4 , then the standardized content ratio is the standardized N 2 / CH 4 The ratio of the content of the standardized total gas is the standardized total gas N 2 / CH 4 The ratio of the content and the standardized adsorbed gas content is the standardized adsorbed gas N 2 / CH 4 Content ratio.

[0021] Among them, the theoretical shale gas N used for standardization 2 / CH 4 The content ratio is based on the standard chart obtained from the simulation experiment. The theoretical adsorption gas N 2 / CH 4 The content ratio is based on the N content under reservoir pressure conditions. 2 / CH 4 Competitive adsorption experiments were performed to obtain

[0022] The embodiment of the present application is a method proposed for the preservation conditions of highly over-mature shale gas. The characteristics of this type of shale gas are fully considered in the process of proposing the method and technology. Different from medium and low-mature shale gas, the embodiment of the present application fully considers the particularity of the gas content of highly over-mature shale gas reservoirs, thereby improving the pertinence and accuracy of determining the preservation conditions of this type of shale gas.

[0023] Figure 1 The implementation flow chart of the method for determining the preservation conditions of highly over-mature shale gas provided in the embodiment of the present application is described in detail as follows:

[0024] In step 101, actual shale reservoir gas content parameters and theoretical shale reservoir gas content parameters of a target shale sample are calculated.

[0025] In the embodiments of the present application, the actual shale reservoir gas content parameters of the target shale sample are calculated through a shale gas analysis experiment, and the theoretical shale reservoir gas content parameters of the target shale sample are calculated through a physical simulation experiment or a statistical analysis method.

[0026] In a possible implementation, the actual shale reservoir gas content parameter may include the total shale gas N 2 Percentage content, total shale gas CH 4 Percentage content, adsorbed gas N 2 Percentage and adsorbed gas CH 4 Percentage content, calculation of actual shale reservoir gas content parameters of target shale samples, may include:

[0027] The actual shale reservoir gas content parameter of the target shale sample is calculated by the first formula, which is:

[0028]

[0029] Among them, γ Ta (N 2 ) is the total shale gas N 2 Percent content, γ Ta (CH 4 ) is the total shale gas CH 4 Percent content, γ Ad (N 2 ) is the adsorbed gas N 2 Percent content, γ Ad (CH 4 ) is the adsorbed gas CH 4 Percent content, γ De-i (N 2 ) is the desorption gas N corresponding to the i-th gas chromatography test 2 Percent content, γ De-i (CH 4 ) is the desorbed gas CH corresponding to the i-th gas chromatography test 4 Percentage, Q De-i is the desorption gas volume corresponding to the i-th gas chromatography test, γ Lo (N 2 ) is the N in the lost gas 2 Percent content, γ Lo (CH4 ) is the CH in the lost gas 4 Percentage, Q Ta is the total gas content of shale, Q De is the amount of gas desorbed from shale, Q Lo is the amount of shale gas loss, M is the total number of gas chromatography tests in the shale gas desorption experiment, N is the number of gas chromatography tests corresponding to the beginning of desorption of adsorbed gas, and i is the number of gas chromatography tests in the shale gas desorption experiment.

[0030] In this embodiment, the actual shale reservoir gas content parameters can be obtained through shale gas analysis experiments. Typical shale samples are selected for pressure coring with reference to the "SY / T 5947-1994 Pressure Coring Operation Procedure", and the collected shale samples are tested for shale gas analysis gas and residual gas with reference to the "SY / T 6940-2020 Shale Gas Content Determination Method", and the collected gas samples are tested and analyzed by gas chromatography and methane carbon isotope.

[0031] Based on the completion of shale gas desorption gas and residual gas testing and related gas chromatography analysis, the total shale gas N 2 Percentage and total shale gas CH 4 Percent content.

[0032] Among them, the total shale gas N 2 The calculation formula for the percentage content is:

[0033]

[0034] Total shale gas CH 4 The calculation formula for the percentage content is:

[0035]

[0036] In the formula, θ Ta (N 2 ),θ Ta (CH 4 ), γ De-i (N 2 ), γ De-i (CH 4 ), γ Lo (N 2 ) and γ Lo (CH 4 ) are in percentage form. The desorption volume Q corresponding to the i-th gas chromatography test De-i The unit is m 3 / t.

[0037] The total gas content of shale in the above formula is Q Ta The calculation formula is:

[0038] Q Ta =Q De +Q Lo

[0039] Among them, the total gas content of shale is Q Ta 、Shale desorption gas volume Q De and shale gas loss Q Lo The unit is m 3 / t.

[0040] Among them, the shale desorption gas volume Q De The calculation formula is:

[0041]

[0042] In addition, the adsorbed gas N of the actual gas in the embodiment of the present application is 2 Percentage and adsorbed gas CH 4 The determination of percentage content requires the use of methane carbon isotope fractionation rules and models to determine the boundary between adsorbed gas and free gas. Here, the desorbed gas corresponding to the Nth gas chromatography test is recorded as the beginning of desorption of the adsorbed gas.

[0043] Adsorbed gas N 2 The calculation formula for the percentage content is:

[0044]

[0045] Adsorbed gas CH 4 The calculation formula for the percentage content is:

[0046]

[0047] In the formula, γ Ad (N 2 ), γ Ad (CH 4 ) are in the form of percentage.

[0048] In a possible implementation, the theoretical shale reservoir gas content parameter may include the theoretical shale gas N 2 Percentage content, theoretical shale gas CH 4 Percentage content, theoretical shale gas N 2 Adsorption amount and theoretical shale gas CH 4 Adsorption amount, calculation of theoretical shale reservoir gas content parameters of target shale samples, may include:

[0049] Obtaining basic shale reservoir parameters of target shale samples, including organic matter reflectivity and reservoir pressure;

[0050] The theoretical shale gas N of the target shale sample is determined by using the organic matter reflectance of the target shale sample.2 Percentage and theoretical shale gas CH 4 Percent content;

[0051] The reservoir pressure of the target shale sample is input into the second formula to obtain the theoretical shale gas N of the target shale sample under the reservoir pressure. 2 Adsorption amount and theoretical shale gas CH 4 Adsorption amount, the second formula is:

[0052]

[0053] Among them, Q Ad-Th (N 2 ) is the theoretical shale gas N under reservoir pressure 2 Adsorption amount, Q Ad-Th (CH 4 ) is the theoretical shale gas CH under reservoir pressure 4 Adsorption amount, Q L (N 2 ) is the pure gas component N adsorbed by the shale reservoir 2 Langmuir volume constant, Q L (CH 4 ) is the pure gas component CH adsorbed by the shale reservoir 4 The Langmuir volume constant, P L (N 2 ) is the pure gas component N adsorbed by the shale reservoir 2 The Langmuir pressure constant, P L (CH 4 ) is the pure gas component CH adsorbed by the shale reservoir 4 The Langmuir pressure constant, P r (N 2 ) is the gas composition N at reservoir pressure 2 The partial pressure, P r (CH 4 ) is the gas component CH at reservoir pressure 4 The partial pressure, ω r (N 2 ) is N at reservoir pressure 2 Volume fraction, ω r (CH 4 ) is CH at reservoir pressure 4 The volume fraction, P r is the reservoir pressure.

[0054] Optionally, before calculating the theoretical shale reservoir gas-bearing parameters of the target shale sample, the embodiment of the present application also needs to obtain the basic shale reservoir parameters of the target shale sample, including the organic reflectance R o and reservoir pressure Pr .

[0055] Organic reflectance R o It characterizes the degree of thermal evolution of shale organic matter. This parameter is subsequently used for theoretical shale gas N 2 Percentage and theoretical shale gas CH 4 For type III kerogen shale samples, the vitrinite reflectance was measured using a spectrophotometer to obtain R o For type I and type II kerogen shale samples lacking vitrinite, the equivalent vitrinite reflectance can be obtained by obtaining the asphalt reflectance. o The shale samples tested were used for subsequent shale gas analysis experiments and N 2 / CH 4 The shale samples in the competitive adsorption experiment were the same sample.

[0056] Reservoir pressure P r It can be obtained through well test analysis or reservoir pressure gradient calculation. This parameter is subsequently used for theoretical shale gas N 2 Adsorption amount and theoretical shale gas CH 4 Obtaining the adsorption amount.

[0057] In addition, the gas composition of shale gas is affected by the thermal evolution of shale organic matter. 2 The percentage is high, and the N content of the actual shale gas composition can be compared with the theoretical shale gas composition. 2 / CH 4 Percentage (i.e. theoretical shale gas N 2 Percentage content, theoretical shale gas CH 4 In order to compare the N content of a specific shale sample with the theoretical gas composition, 2 / CH 4 The difference in percentage content requires the establishment of a theoretical shale gas N 2 / CH 4 The correspondence or chart between percentage content and degree of thermal evolution.

[0058] For the theoretical shale gas N 2 / CH 4 The corresponding relationship or chart of percentage content and thermal evolution degree can be established by the following methods:

[0059] (1) The thermal simulation experiment method can be used to conduct thermal simulation experiments on shale samples with low thermal evolution and specific kerogen types to obtain experimental gas N 2 / CH 4 The percentage content varies with temperature and thermal evolution index parameter organic matter reflectivity R oThe mathematical relationship or diagram between them.

[0060] (2) The results of different thermal simulation experiments on specific kerogen types of shales in previous studies can be collected, and the experimental gas N 2 / CH 4 Percent content with thermal evolution degree index parameter organic matter reflectivity R o The mathematical relationship or diagram between them.

[0061] (3) The gas composition data of shale gas in areas with good preservation conditions can be collected, and the stratigraphic position and kerogen type of the shale gas reservoir can be ensured to be consistent with the shale reservoir to be determined. 2 / CH 4 Percentage content and thermal evolution index parameters Organic matter reflectivity R o The mathematical relationship or diagram between them.

[0062] Given the unknown shale reservoir thermal evolution index parameter, organic reflectivity R o In the case of 2 Percentage and theoretical shale gas CH 4 The percentage content provides a comparative benchmark for subsequent judgment of shale gas preservation conditions, and can achieve targeted and accurate judgment of the preservation conditions of highly mature shale gas.

[0063] For theoretical shale gas N 2 Adsorption amount and theoretical shale gas CH 4 The adsorption amount is calculated to obtain the theoretical shale gas N 2 / CH 4 The theoretical shale gas N 2 Percentage and theoretical shale gas CH 4 Percentage of N 2 / CH 4 Proportional N 2 and CH 4 Competitive adsorption experiment. Complete N 2 and CH 4 After competitive adsorption experiments, the theoretical shale gas N 2 / CH 4 Adsorbed gas volume (i.e. theoretical shale gas N 2 Adsorption amount and theoretical shale gas CH 4 The analysis process of adsorption capacity is as follows:

[0064] According to the extended Langmuir equation (EL equation):

[0065]

[0066] Among them, Qm is the adsorption amount of component m in the mixed gas by the adsorbent, in units of m 3 / t;Q Lm is the Langmuir volume constant of pure gas component m adsorbed by the adsorbent, in m 3 / t;P Lm is the Langmuir pressure constant of pure gas component m adsorbed by the adsorbent, in MPa; P m is the partial pressure of gas component m, in MPa; n is the number of multi-component mixed gas components; Pj is the partial pressure of gas component j, in MPa; P Lj is the Langmuir pressure constant of pure gas component j adsorbed by the adsorbent, in MPa.

[0067] In shale reservoirs N 2 / CH 4 In the binary gas mixture isotherm adsorption experiment, the N 2 and CH 4 The adsorption amount can be expressed as:

[0068]

[0069] Among them, Q(N 2 ) and Q(CH 4 ) are the theoretical shale gas N 2 Adsorption amount and theoretical shale gas CH 4 Adsorption capacity, unit: m 3 / t;Q L (N 2 ) and Q L (CH 4 ) are the pure gas components N adsorbed by shale reservoirs 2 and CH 4 Langmuir volume constant, in m 3 / t;P L (N 2 ) and P L (CH 4 ) are the pure gas components N adsorbed by shale reservoirs 2 and CH 4 Langmuir pressure constant, in MPa; P(N 2 ) and P(CH 4 ) are the gas components N at adsorption equilibrium 2 and CH 4 The partial pressure of is in MPa.

[0070] Among them, the gas component N at adsorption equilibrium 2 and CH 4 The partial pressure P(N2 ) and P(CH 4 ) is calculated as follows:

[0071]

[0072] Among them, P B is the adsorption equilibrium pressure, in MPa; ω(N 2 ) and ω(CH 4 ) are the gas components N in the shale reservoir when the binary mixed gas is adsorbed in equilibrium 2 and CH 4 The volume fraction, in percentage form, can be obtained by gas chromatography analysis.

[0073] The present application embodiment is based on N 2 and CH 4 Competitive adsorption experimental results for obtaining binary gas mixture N 2 and CH 4 After the equation parameters in the adsorption amount calculation formula are added, the reservoir pressure P r Substituting into the corresponding formula, we can obtain the theoretical shale gas N 2 / CH 4 Adsorption volume.

[0074] The theoretical shale gas N under reservoir pressure is 2 The calculation formula of adsorption amount is:

[0075]

[0076] Theoretical shale gas CH under reservoir pressure conditions 4 The calculation formula of adsorption amount is:

[0077]

[0078] In the formula, the theoretical shale gas N under reservoir pressure is 2 Adsorption amount Q Ad -T h (N 2 ), theoretical shale gas CH under reservoir pressure 4 Adsorption amount Q Ad -T h (CH 4 ), shale reservoir adsorption of pure gas components N 2 The Langmuir volume constant Q L (N 2 ) and shale reservoir adsorption of pure gas component CH 4 The Langmuir volume constant Q L (CH 4 ) are all in m 3 / t; Shale reservoir adsorbs pure gas components N 2 The Langmuir pressure constant P L (N 2 ), the rock reservoir absorbs pure gas component CH 4 The Langmuir pressure constant P L (CH 4 ), gas composition N at shale reservoir pressure 2 The partial pressure P r (N 2 ) and the gas composition CH at reservoir pressure 4 The partial pressure P r (CH 4 ) are all in MPa.

[0079] The gas component N under reservoir pressure in the above formula is 2 and CH 4 The partial pressure P r (N 2 ) and P r (CH 4 ) is calculated as:

[0080]

[0081] In the formula, the reservoir pressure P r The unit is MPa, N at reservoir pressure 2 Volume fraction ω r (N 2 ) and CH at reservoir pressure 4 Volume fraction ω r (CH 4 ) are in percentage form.

[0082] In step 102, based on the actual shale reservoir gas content parameters of the target shale sample, a first content ratio of the target shale sample is calculated, where the first content ratio is a ratio of actual shale gas percentage content.

[0083] In the embodiment of the present application, the actual shale reservoir gas content parameter of the target shale sample calculated in step 101 is used to calculate a first content ratio of the actual shale gas percentage content of the target shale sample.

[0084] In a possible implementation, the first content ratio may include the actual total gas N 2 / CH 4 Content ratio and actual adsorbed gas N 2 / CH 4 The content ratio is calculated based on the actual shale reservoir gas-bearing parameters of the target shale sample, and includes:

[0085] The first content ratio of the target shale sample is calculated by the third formula, and the third formula is:

[0086]

[0087] Among them, R Ta (N 2 / CH 4 ) is the actual total gas N 2 / CH 4 Content ratio, R Ad (N 2 / CH 4 ) is the actual adsorbed gas N 2 / CH 4 Content ratio, γ Ta (N 2 ) is the total shale gas N 2 Percent content, γ Ta (CH 4 ) is the total shale gas CH 4 Percent content, γ Ad (N 2 ) is the adsorbed gas N 2 Percent content, γ Ad (CH 4 ) is the adsorbed gas CH 4 Percent content.

[0088] Optionally, the total shale gas N 2 Percentage γ Ta (N 2 ) and total shale gas CH 4 Percentage γ Ta (CH 4 )Enter the formula The actual total gas N of the target shale sample is calculated. 2 / CH 4 Content ratio R Ta (N 2 / CH 4 ), dimensionless.

[0089] The adsorbed gas N 2 Percentage γ Ad (N 2 ) and adsorbed gas CH 4 Percentage γ Ad (CH 4 )Enter the formula The actual adsorbed gas N of the target shale sample is calculated. 2 / CH 4 Content ratio R Ad (N 2 / CH 4), which is also dimensionless.

[0090] In step 103, based on the theoretical reservoir gas content parameter of the target shale sample, a second content ratio of the target shale sample is calculated, where the second content ratio is a ratio of the theoretical shale gas percentage content.

[0091] In the embodiment of the present application, the second content ratio of the theoretical shale gas percentage of the target shale sample is calculated using the theoretical shale reservoir gas content parameter of the target shale sample calculated in step 101.

[0092] In a possible implementation, the second content ratio may include the theoretical shale gas N 2 / CH 4 Content ratio and theoretical adsorption gas N 2 / CH 4 The content ratio is based on the theoretical shale reservoir gas-bearing parameters of the target shale sample, and a second content ratio of the target shale sample is calculated, including:

[0093] The second content ratio of the target shale sample is calculated by the fourth formula, and the fourth formula is:

[0094]

[0095] Among them, R Ta-Th (N 2 / CH 4 ) is the theoretical shale gas N 2 / CH 4 Content ratio, R Ad-Th (N 2 / CH 4 ) is the theoretical adsorbed gas N 2 / CH 4 Content ratio, γ Ta -T h (N 2 ) is the theoretical shale gas N 2 Percent content, θ Ta-Th (CH 4 ) is the theoretical shale gas CH 4 Percentage, Q Ad-Th (N 2 ) is the theoretical shale gas N under reservoir pressure 2 Adsorption amount, Q Ad-Th (CH 4 ) is the theoretical shale gas CH under reservoir pressure 4 Adsorption amount.

[0096] Optionally, the theoretical shale gas N 2 Percentage γ Ta -T h (N 2) and theoretical shale gas CH 4 Percentage content θTa-Th(CH 4 )Enter the formula Calculate the theoretical shale gas N of the target shale sample 2 / CH 4 Content ratio R Ta -T h (N 2 / CH 4 ), dimensionless.

[0097] Similarly, the theoretical shale gas N 2 Adsorption amount Q Ad-Th (N 2 ) and theoretical shale gas CH under reservoir pressure 4 Adsorption amount Q Ad-Th (CH 4 )Enter the formula The theoretical adsorbed gas N of the target shale sample was calculated. 2 / CH 4 Content ratio R Ad-Th (N 2 / CH 4 ), dimensionless.

[0098] The present embodiment takes into account the actual and theoretical shale gas N 2 / CH 4 The difference in N content is also analyzed from the perspectives of total gas and adsorbed gas in shale reservoirs. 2 / CH 4 Judging shale gas preservation conditions based on content differences can avoid analyzing complex shale gas geological factors and parameters. The preservation conditions of highly mature shales can be determined by considering only the gas composition of shale gas, making the entire determination process low-cost, simple and reliable.

[0099] In step 104, a standardized content ratio of the target shale sample is calculated using the first content ratio and the second content ratio of the target shale sample.

[0100] In the embodiment of the present application, the first content ratio of the target shale sample calculated in step 102 and the second content ratio of the target shale sample calculated in step 103 are used to calculate the standardized content ratio of the target shale sample, that is, the standardized N 2 / CH 4 Content ratio.

[0101] In a possible implementation, the first content ratio may include the actual total gas N 2 / CH 4 Content ratio and actual adsorbed gas N 2 / CH 4content ratio, the second content ratio may include theoretical shale gas N 2 / CH 4 Content ratio and theoretical adsorption gas N 2 / CH 4 Content ratio, standardized content ratio is standardized N 2 / CH 4 The content ratio, using the first content ratio and the second content ratio of the target shale sample, calculates the standardized content ratio of the target shale sample, including:

[0102] The actual total gas N 2 / CH 4 Content ratio and theoretical shale gas N 2 / CH 4 The content ratio is input into the fifth formula to calculate the standardized total gas N of the target shale sample. 2 / CH 4 Content ratio;

[0103] The actual adsorbed gas N 2 / CH 4 Content ratio and theoretical adsorption gas N 2 / CH 4 The content ratio is input into the sixth formula to calculate the standardized adsorbed gas N of the target shale sample. 2 / CH 4 Content ratio;

[0104] Using the normalized total gas N of the target shale sample 2 / CH 4 Content ratio and standardized adsorbed gas N 2 / CH 4 content ratio, calculate the standardized N 2 / CH 4 Content ratio;

[0105] Among them, the fifth formula is:

[0106]

[0107] Among them, I Ta (N 2 / CH 4 ) is the standardized total gas N 2 / CH 4 Content ratio, R Ta (N 2 / CH 4 ) is the actual total gas N 2 / CH 4 Content ratio, R Ta-Th (N 2 / CH 4 ) is the theoretical shale gas N2 / CH 4 Content ratio;

[0108] The sixth formula is:

[0109]

[0110] Among them, I Ad (N 2 / CH 4 ) is the standardized adsorbed gas N 2 / CH 4 Content ratio, RA d (N 2 / CH 4 ) is the actual adsorbed gas N 2 / CH 4 Content ratio, RA d-Th (N 2 / CH 4 ) is the theoretical adsorbed gas N 2 / CH 4 Content ratio.

[0111] The embodiment of the present application adopts the standardized total gas N 2 / CH 4 Content ratio and adsorbed gas N 2 / CH 4 Standardized N constructed by content ratio 2 / CH 4 The content ratio is used to judge the preservation conditions of over-mature shale gas. 2 / CH 4 The content ratio is determined by the actual total gas N 2 / CH 4 Content ratio and theoretical shale gas N 2 / CH 4 The content ratio is compared to obtain the standardized adsorbed gas N 2 / CH 4 The content ratio is determined by the actual adsorption gas N 2 / CH 4 Content ratio and theoretical adsorption gas N 2 / CH 4 The content ratio is compared to obtain.

[0112] Specifically, the standardized total gas N 2 / CH 4 The calculation formula of content ratio is:

[0113]

[0114] Among them, I Ta (N 2 / CH4 ) is the standardized total gas N 2 / CH 4 Content ratio, dimensionless; R Ta (N 2 / CH 4 ) is the actual total gas N 2 / CH 4 Content ratio, dimensionless; R Ta -T h (N 2 / CH 4 ) is the theoretical shale gas N 2 / CH 4 Content ratio, dimensionless.

[0115] Standardized adsorbed gas N 2 / CH 4 The calculation formula of content ratio is:

[0116]

[0117] Among them, I Ta (N 2 / CH 4 ) is the standardized total gas N 2 / CH 4 Content ratio, dimensionless; R Ta (N 2 / CH 4 ) is the actual total gas N 2 / CH 4 Content ratio, dimensionless; R Ta -T h (N 2 / CH 4 ) is the theoretical shale gas N 2 / CH 4 Content ratio, dimensionless.

[0118] In one possible implementation, the standardized total gas N 2 / CH 4 Content ratio and standardized adsorbed gas N 2 / CH 4 content ratio, calculate the standardized N 2 / CH 4 Content ratios may include:

[0119] The normalized total gas N 2 / CH 4 Content ratio and standardized adsorbed gas N 2 / CH 4 The content ratio is input into the seventh formula to calculate the standardized N2 / CH 4 Content ratio, the seventh formula is:

[0120]

[0121] Among them, I(N 2 / CH 4 ) is the standardized N of the target shale sample 2 / CH 4 Content ratio.

[0122] Optionally, in obtaining the standardized total gas N 2 / CH 4 Content ratio I Ta (N 2 / CH 4 ) and standardized adsorbed gas N 2 / CH 4 Content ratio IAd(N 2 / CH 4 ) based on which the standardized N 2 / CH 4 The content ratio is calculated as follows:

[0123]

[0124] Among them, I(N 2 / CH 4 ) is the standardized N of the target shale sample 2 / CH 4 Content ratio, dimensionless.

[0125] The standardized N proposed in the embodiment of this application 2 / CH 4 The content ratio is used to determine the preservation condition type of highly mature shale gas. 2 / CH 4 The content ratio is based on the standardized total gas N 2 / CH 4 Content ratio and standardized adsorbed gas N 2 / CH 4 The normalized total gas N 2 / CH 4 The theoretical shale gas N used for the content ratio 2 / CH 4 The content ratio is based on the standard chart obtained from the simulation experiment. The theoretical adsorption gas N 2 / CH 4 The content ratio is based on the N 2 / CH 4The data are obtained through competitive adsorption experiments, which can achieve the targeted and accurate determination of the preservation conditions of highly over-mature shale gas.

[0126] In step 105, the shale gas preservation condition type of the target shale sample is determined according to the standardized content ratio of the target shale sample, and the shale gas preservation condition type includes normal and abnormal.

[0127] In the embodiment of the present application, the shale gas preservation condition type of the target shale sample is determined according to the standardized content ratio of the target shale sample calculated in step 104. The shale gas preservation condition type includes normal and abnormal. Normal means that the shale gas preservation condition of the target shale sample is not significantly damaged, and abnormal means that the shale preservation condition of the target shale sample is damaged.

[0128] The standardized content ratio calculated in the embodiment of the present application can be quantitatively characterized, which is not only conducive to providing a quantitative criterion basis for determining the structure of the storage conditions, but also can realize the software, automation and intelligence of the entire judgment process, thereby greatly reducing the human labor and human operation errors.

[0129] In a possible implementation, determining the shale gas preservation condition type of the target shale sample according to the standardized content ratio of the target shale sample may include:

[0130] Determine whether the standardized content ratio of the target shale sample is not greater than a preset threshold;

[0131] If the standardized content ratio of the target shale sample is not greater than the preset threshold, the shale gas preservation condition type of the target shale sample is determined to be normal;

[0132] If the standardized content ratio of the target shale sample is greater than a preset threshold, it is determined that the shale gas preservation condition type of the target shale sample is abnormal.

[0133] Optionally, it is determined whether the standardized content ratio of the target shale sample is not greater than a preset threshold value. If so, it indicates that the shale gas preservation conditions of the target shale sample are normal. If so, it indicates that the shale gas preservation conditions of the target shale sample are abnormal.

[0134] For example, the preset threshold is 1+δ, and the standardized content ratio I(N 2 / CH 4 ), if I(N 2 / CH 4 )≤1+δ, it indicates that the shale gas preservation conditions of the target shale sample are normal. 2 / CH 4 )>1+δ, it indicates that the shale gas preservation conditions of the target shale sample are abnormal.

[0135] The value of δ may be 0.1, 0.3, or any other value based on actual needs, which is not limited in the embodiments of the present application.

[0136] This application can not only directly evaluate the preservation conditions of highly over-mature shale gas, but also lay a good foundation for understanding the distribution patterns of this type of shale gas, optimizing favorable areas and evaluating resources. The preservation condition determination results obtained based on the embodiments of this application can help to form a more scientific and reasonable understanding of the determination of favorable areas, and thus provide a scientific basis for subsequent exploration and development deployment.

[0137] Moreover, the method for determining the preservation conditions of highly over-mature shale gas proposed in the embodiment of the present application is also inspiring and instructive for determining the preservation conditions of other different types of natural gas, such as coalbed methane, tight sandstone gas, tight carbonate gas, conventional natural gas, etc. It also contributes to the systematic study and overall understanding of the geological laws of the distribution of multiple types of natural gas, and can also provide a certain basis for the formulation of relevant natural gas exploration and development strategies.

[0138] The present application provides a method for determining the preservation conditions of highly over-mature shale gas, which comprises calculating the actual shale reservoir gas content parameters and theoretical shale reservoir gas content parameters of a target shale sample; calculating a first content ratio of the target shale sample based on the actual shale reservoir gas content parameters of the target shale sample, wherein the first content ratio is a ratio of actual shale gas percentage contents; calculating a second content ratio of the target shale sample based on the theoretical reservoir gas content parameters of the target shale sample, wherein the second content ratio is a ratio of theoretical shale gas percentage contents; calculating a standardized content ratio of the target shale sample using the first content ratio and the second content ratio of the target shale sample; and determining the shale gas preservation condition type of the target shale sample according to the standardized content ratio of the target shale sample, wherein the shale gas preservation condition types include normal and abnormal. The present application calculates a standardized content ratio by using the first content ratio and the second content ratio, which not only improves the accuracy and specificity of determining shale gas preservation conditions, but also avoids analyzing complex shale gas geological factors and parameters. It is only necessary to consider the gas composition of shale gas to realize the judgment of the preservation conditions of highly mature shale gas, making the entire judgment process low-cost and simple and feasible.

[0139] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0140] The following is an embodiment of the device of the present application. For details not described in detail, please refer to the corresponding method embodiment described above.

[0141] Figure 2The schematic diagram of the structure of the device for determining the storage conditions of highly over-mature shale gas provided in the embodiment of the present application is shown. For the convenience of explanation, only the part related to the embodiment of the present application is shown, which is described in detail as follows:

[0142] like Figure 2 As shown, the highly over-mature shale gas preservation condition determination device 2 comprises:

[0143] A parameter calculation module 21 is used to calculate actual shale reservoir gas-bearing parameters and theoretical shale reservoir gas-bearing parameters of a target shale sample;

[0144] A first ratio calculation module 22, used to calculate a first content ratio of the target shale sample based on the actual shale reservoir gas-bearing parameters of the target shale sample, wherein the first content ratio is a ratio of actual shale gas percentage content;

[0145] A second ratio calculation module 23, used to calculate a second content ratio of the target shale sample based on the theoretical reservoir gas content parameter of the target shale sample, where the second content ratio is a ratio of the theoretical shale gas percentage content;

[0146] A standard ratio calculation module 24, used to calculate a standardized content ratio of the target shale sample using the first content ratio and the second content ratio of the target shale sample;

[0147] The condition determination module 25 is used to determine the shale gas preservation condition type of the target shale sample according to the standardized content ratio of the target shale sample, and the shale gas preservation condition type includes normal and abnormal.

[0148] The present application provides a device for determining preservation conditions of highly over-mature shale gas, which calculates actual shale reservoir gas content parameters and theoretical shale reservoir gas content parameters of a target shale sample; based on the actual shale reservoir gas content parameters of the target shale sample, calculates a first content ratio of the target shale sample, the first content ratio being a ratio of actual shale gas percentage content; based on the theoretical reservoir gas content parameters of the target shale sample, calculates a second content ratio of the target shale sample, the second content ratio being a ratio of theoretical shale gas percentage content; using the first content ratio and the second content ratio of the target shale sample, calculates a standardized content ratio of the target shale sample; and according to the standardized content ratio of the target shale sample, determines the shale gas preservation condition type of the target shale sample, the shale gas preservation condition types including normal and abnormal. The present application calculates a standardized content ratio by using the first content ratio and the second content ratio, which not only improves the accuracy and specificity of determining shale gas preservation conditions, but also avoids analyzing complex shale gas geological factors and parameters. It is only necessary to consider the gas composition of shale gas to realize the judgment of the preservation conditions of highly mature shale gas, making the entire judgment process low-cost and simple and feasible.

[0149] In a possible implementation, the actual shale reservoir gas content parameter may include the total shale gas N 2 Percentage content, total shale gas CH 4 Percentage content, adsorbed gas N 2 Percentage and adsorbed gas CH 4 The percentage and parameter calculation module can be used for:

[0150] The actual shale reservoir gas content parameter of the target shale sample is calculated by the first formula, which is:

[0151]

[0152] Among them, γ Ta (N 2 ) is the total shale gas N 2 Percent content, γ Ta (CH 4 ) is the total shale gas CH 4 Percent content, γ Ad (N 2 ) is the adsorbed gas N 2 Percent content, γ Ad (CH 4 ) is the adsorbed gas CH 4 Percent content, γ De-i (N 2 ) is the desorption gas N corresponding to the i-th gas chromatography test 2 Percent content, γ De-i (CH 4 ) is the desorbed gas CH corresponding to the i-th gas chromatography test 4 Percentage, Q De-i is the desorption gas volume corresponding to the i-th gas chromatography test, γ Lo (N 2 ) is the N in the lost gas 2 Percent content, γ Lo (CH 4 ) is the CH in the lost gas 4 Percentage, Q Ta is the total gas content of shale, Q De is the amount of gas desorbed from shale, Q Lo is the amount of shale gas loss, M is the total number of gas chromatography tests in the shale gas desorption experiment, N is the number of gas chromatography tests corresponding to the beginning of desorption of adsorbed gas, and i is the number of gas chromatography tests in the shale gas desorption experiment.

[0153] In a possible implementation, the theoretical shale reservoir gas content parameter may include the theoretical shale gas N 2 Percentage content, theoretical shale gas CH 4 Percentage content, theoretical shale gas N 2Adsorption amount and theoretical shale gas CH 4 Adsorption amount, parameter calculation module can be used for:

[0154] Obtaining basic shale reservoir parameters of target shale samples, including organic matter reflectivity and reservoir pressure;

[0155] The theoretical shale gas N of the target shale sample is determined by using the organic matter reflectance of the target shale sample. 2 Percentage and theoretical shale gas CH 4 Percent content;

[0156] The reservoir pressure of the target shale sample is input into the second formula to obtain the theoretical shale gas N of the target shale sample under the reservoir pressure. 2 Adsorption amount and theoretical shale gas CH 4 Adsorption amount, the second formula is:

[0157]

[0158] Among them, Q Ad-Th (N 2 ) is the theoretical shale gas N under reservoir pressure 2 Adsorption amount, Q Ad-Th (CH 4 ) is the theoretical shale gas CH under reservoir pressure 4 Adsorption amount, Q L (N 2 ) is the pure gas component N adsorbed by the shale reservoir 2 Langmuir volume constant, Q L (CH 4 ) is the pure gas component CH adsorbed by the shale reservoir 4 The Langmuir volume constant, P L (N 2 ) is the pure gas component N adsorbed by the shale reservoir 2 The Langmuir pressure constant, P L (CH 4 ) is the pure gas component CH adsorbed by the shale reservoir 4 The Langmuir pressure constant, P r (N 2 ) is the gas composition N at reservoir pressure 2 The partial pressure, P r (CH 4 ) is the gas component CH at reservoir pressure 4 The partial pressure, ω r (N 2 ) is N at reservoir pressure 2 Volume fraction, ω r (CH 4) is CH at reservoir pressure 4 The volume fraction, P r is the reservoir pressure.

[0159] In a possible implementation, the first content ratio may include the actual total gas N 2 / CH 4 Content ratio and actual adsorbed gas N 2 / CH 4 Content ratio, the first ratio calculation module can be used for:

[0160] The first content ratio of the target shale sample is calculated by the third formula, and the third formula is:

[0161]

[0162] Among them, R Ta (N 2 / CH 4 ) is the actual total gas N 2 / CH 4 Content ratio, R Ad (N 2 / CH 4 ) is the actual adsorbed gas N 2 / CH 4 Content ratio, γ Ta (N 2 ) is the total shale gas N 2 Percent content, γ Ta (CH 4 ) is the total shale gas CH 4 Percent content, γ Ad (N 2 ) is the adsorbed gas N 2 Percent content, γ Ad (CH 4 ) is the adsorbed gas CH 4 Percent content.

[0163] In a possible implementation, the second content ratio may include the theoretical shale gas N 2 / CH 4 Content ratio and theoretical adsorption gas N 2 / CH 4 Content ratio, the second ratio calculation module can be used for:

[0164] The second content ratio of the target shale sample is calculated by the fourth formula, and the fourth formula is:

[0165]

[0166] Among them, R Ta-Th (N 2 / CH4 ) is the theoretical shale gas N 2 / CH 4 Content ratio, R Ad-Th (N 2 / CH 4 ) is the theoretical adsorbed gas N 2 / CH 4 Content ratio, θ Ta -T h (N 2 ) is the theoretical shale gas N 2 Percent content, θ Ta-Th (CH 4 ) is the theoretical shale gas CH 4 Percentage, Q Ad-Th (N 2 ) is the theoretical shale gas N under reservoir pressure 2 Adsorption amount, Q Ad-Th (CH 4 ) is the theoretical shale gas CH under reservoir pressure 4 Adsorption amount.

[0167] In a possible implementation, the first content ratio may include the actual total gas N 2 / CH 4 Content ratio and actual adsorbed gas N 2 / CH 4 content ratio, the second content ratio may include theoretical shale gas N 2 / CH 4 Content ratio and theoretical adsorption gas N 2 / CH 4 Content ratio, standardized content ratio is standardized N 2 / CH 4 Content ratio, standard ratio calculation module can be used for:

[0168] The actual total gas N 2 / CH 4 Content ratio and theoretical shale gas N 2 / CH 4 The content ratio is input into the fifth formula to calculate the standardized total gas N of the target shale sample. 2 / CH 4 Content ratio;

[0169] The actual adsorbed gas N 2 / CH 4 Content ratio and theoretical adsorption gas N 2 / CH 4 The content ratio is input into the sixth formula to calculate the standardized adsorbed gas N of the target shale sample. 2 / CH 4 Content ratio;

[0170] Using the normalized total gas N of the target shale sample 2 / CH 4 Content ratio and standardized adsorbed gas N 2 / CH 4 content ratio, calculate the standardized N 2 / CH 4 Content ratio;

[0171] Among them, the fifth formula is:

[0172]

[0173] Among them, I Ta (N 2 / CH 4 ) is the standardized total gas N 2 / CH 4 Content ratio, R Ta (N 2 / CH 4 ) is the actual total gas N 2 / CH 4 Content ratio, R Ta -T h (N 2 / CH 4 ) is the theoretical shale gas N 2 / CH 4 Content ratio;

[0174] The sixth formula is:

[0175]

[0176] Among them, I Ad (N 2 / CH 4 ) is the standardized adsorbed gas N 2 / CH 4 Content ratio, R Ad (N 2 / CH 4 ) is the actual adsorbed gas N 2 / CH 4 Content ratio, R Ad-Th (N 2 / CH 4 ) is the theoretical adsorbed gas N 2 / CH 4 Content ratio.

[0177] In a possible implementation, the standard ratio calculation module may also be used for:

[0178] The normalized total gas N 2 / CH4 Content ratio and standardized adsorbed gas N 2 / CH 4 The content ratio is input into the seventh formula to calculate the standardized N 2 / CH 4 Content ratio, the seventh formula is:

[0179]

[0180] Among them, I(N 2 / CH 4 ) is the standardized N of the target shale sample 2 / CH 4 Content ratio.

[0181] In a possible implementation, the condition determination module may be used to:

[0182] Determine whether the standardized content ratio of the target shale sample is not greater than a preset threshold;

[0183] If the standardized content ratio of the target shale sample is not greater than the preset threshold, the shale gas preservation condition type of the target shale sample is determined to be normal;

[0184] If the standardized content ratio of the target shale sample is greater than a preset threshold, it is determined that the shale gas preservation condition type of the target shale sample is abnormal.

[0185] Figure 3 is a schematic diagram of a terminal provided in an embodiment of the present application. Figure 3 As shown, the terminal 3 of this embodiment includes: a processor 30, a memory 31, and a computer program 32 stored in the memory 31 and executable on the processor 30. When the processor 30 executes the computer program 32, the steps in the above-mentioned embodiments of the method for determining the preservation conditions of highly mature shale gas are implemented, for example Figure 1 Alternatively, when the processor 30 executes the computer program 32, the functions of each module / unit in the above-mentioned device embodiments are realized, for example Figure 2 The functions of each module are shown.

[0186] Exemplarily, the computer program 32 may be divided into one or more modules / units, which are stored in the memory 31 and executed by the processor 30 to complete the present application. The one or more modules / units may be a series of computer program instruction segments capable of completing specific functions, which are used to describe the execution process of the computer program 32 in the terminal 3. For example, the computer program 32 may be divided into Figure 2 The modules shown.

[0187] The terminal 3 may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The terminal 3 may include, but is not limited to, a processor 30 and a memory 31. Those skilled in the art will appreciate that Figure 3 It is only an example of terminal 3 and does not constitute a limitation on terminal 3. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the terminal may also include input and output devices, network access devices, buses, etc.

[0188] The processor 30 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0189] The memory 31 may be an internal storage unit of the terminal 3, such as a hard disk or memory of the terminal 3. The memory 31 may also be an external storage device of the terminal 3, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the terminal 3. Further, the memory 31 may also include both an internal storage unit of the terminal 3 and an external storage device. The memory 31 is used to store the computer program and other programs and data required by the terminal. The memory 31 may also be used to temporarily store data that has been output or is to be output.

[0190] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0191] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0192] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0193] In the embodiments provided in the present application, it should be understood that the disclosed devices / terminals and methods can be implemented in other ways. For example, the device / terminal embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0194] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0195] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0196] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the above-mentioned various high-maturity shale gas preservation condition determination method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device that can carry the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practices in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practices, computer-readable media does not include electrical carrier signals and telecommunication signals.

[0197] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for determining storage conditions of highly over-mature shale gas, characterized in that: include: Calculate actual shale reservoir gas content parameters and theoretical shale reservoir gas content parameters of target shale samples; Calculating a first content ratio of the target shale sample based on an actual shale reservoir gas-bearing parameter of the target shale sample, wherein the first content ratio is a ratio of actual shale gas percentage content; Based on the theoretical reservoir gas content parameter of the target shale sample, calculating a second content ratio of the target shale sample, wherein the second content ratio is a ratio of theoretical shale gas percentage content; Calculating a standardized content ratio of the target shale sample using the first content ratio and the second content ratio of the target shale sample; Determining the shale gas preservation condition type of the target shale sample according to the standardized content ratio of the target shale sample, wherein the shale gas preservation condition type includes normal and abnormal; Wherein, the first content ratio includes the actual total gas Content ratio and actual adsorbed gas content ratio, wherein the second content ratio includes theoretical shale gas Content ratio and theoretical adsorption gas content ratio, wherein the standardized content ratio is the standardized Content ratio.

2. The method for determining storage conditions of highly over-mature shale gas according to claim 1, characterized in that: The actual shale reservoir gas content parameters include shale total gas Percentage content, total shale gas Percent content, adsorbed gas Percent content and adsorbed gas The actual shale reservoir gas content parameters of the target shale sample are calculated as follows: The actual shale reservoir gas content parameter of the target shale sample is calculated by a first formula, wherein the first formula is: in, is the total shale gas Percent content, is the total shale gas Percent content, The adsorbed gas Percent content, The adsorbed gas Percent content, For the The desorption gas corresponding to the gas chromatography test Percent content, For the The desorption gas corresponding to the gas chromatography test Percent content, For the The desorption volume corresponding to the gas chromatography test, For loss of air Percent content, For loss of air Percent content, is the total gas content of shale, is the amount of gas desorbed from shale, The gas loss from shale is is the total number of gas chromatography tests in the shale gas desorption experiment, is the number of gas chromatography tests corresponding to the start of desorption of the adsorbed gas, is the number of gas chromatography tests in the shale gas desorption experiment.

3. The method for determining storage conditions of highly over-mature shale gas according to claim 1, characterized in that: The theoretical shale reservoir gas content parameters include theoretical shale gas Percentage, theoretical shale gas Percentage, theoretical shale gas Adsorption and theoretical shale gas Adsorption amount, the theoretical shale reservoir gas-bearing parameters of the calculated target shale sample include: Obtaining basic shale reservoir parameters of the target shale sample, wherein the basic shale reservoir parameters include organic reflectivity and reservoir pressure; The theoretical shale gas of the target shale sample is determined by using the organic matter reflectance of the target shale sample. Percentage and theoretical shale gas Percent content; The reservoir pressure of the target shale sample is input into the second formula to obtain the theoretical shale gas of the target shale sample under the reservoir pressure. Adsorption and theoretical shale gas Adsorption amount, the second formula is: in, is the theoretical shale gas under the reservoir pressure Adsorption amount, is the theoretical shale gas under the reservoir pressure Adsorption amount, Adsorption of pure gas components for shale reservoirs The Langmuir volume constant, Adsorption of pure gas components for shale reservoirs The Langmuir volume constant, Adsorption of pure gas components for shale reservoirs The Langmuir pressure constant, Adsorption of pure gas components for shale reservoirs The Langmuir pressure constant, is the gas composition at reservoir pressure The partial pressure, is the gas composition at reservoir pressure The partial pressure, The reservoir pressure The volume fraction of The reservoir pressure The volume fraction of is the reservoir pressure.

4. The method for determining storage conditions of highly over-mature shale gas according to claim 1, characterized in that: The first content ratio includes the actual total gas Content ratio and actual adsorbed gas The first content ratio of the target shale sample is calculated based on the actual shale reservoir gas-bearing parameter of the target shale sample, comprising: The first content ratio of the target shale sample is calculated by a third formula, and the third formula is: in, The actual total gas / Content ratio, The actual adsorbed gas / Content ratio, Total shale gas Percent content, Total shale gas Percent content, For adsorption gas Percent content, For adsorption gas Percent content.

5. The method for determining storage conditions of highly over-mature shale gas according to claim 1, characterized in that: The second content ratio includes theoretical shale gas Content ratio and theoretical adsorption gas The step of calculating a second content ratio of the target shale sample based on a theoretical shale reservoir gas-bearing parameter of the target shale sample comprises: The second content ratio of the target shale sample is calculated by a fourth formula, and the fourth formula is: in, The theoretical shale gas / Content ratio, The theoretical adsorption gas / Content ratio, Theoretical shale gas Percent content, Theoretical shale gas Percent content, is the theoretical shale gas under reservoir pressure Adsorption amount, is the theoretical shale gas under reservoir pressure Adsorption amount.

6. The method for determining storage conditions of highly over-mature shale gas according to claim 1, characterized in that: The step of calculating the standardized content ratio of the target shale sample by using the first content ratio and the second content ratio of the target shale sample comprises: The actual total gas / The content ratio and the theoretical shale gas / The content ratio is input into the fifth formula to calculate the standardized total gas content of the target shale sample. / Content ratio; The actual adsorbed gas / The content ratio and the theoretical adsorption gas / The content ratio is input into the sixth formula to calculate the standardized adsorbed gas of the target shale sample. / Content ratio; The standardized total gas / Content ratio and standardized adsorption gas / content ratio, calculate the standardized / Content ratio; Wherein, the fifth formula is: in, The standardized total gas / Content ratio, The actual total gas / Content ratio, The theoretical shale gas / Content ratio; The sixth formula is: in, The standardized adsorption gas / Content ratio, The actual adsorbed gas / Content ratio, The theoretical adsorption gas / Content ratio.

7. The method for determining storage conditions of highly over-mature shale gas according to claim 6, characterized in that: The standardized total gas / Content ratio and standardized adsorption gas / content ratio, calculate the standardized / Content ratios, including: The standardized total gas / Content ratio and standardized adsorption gas / The content ratio is input into the seventh formula to calculate the standardized / Content ratio, the seventh formula is: in, Standardization of the target shale samples / Content ratio.

8. The method for determining storage conditions of highly over-mature shale gas according to claim 1, characterized in that: Determining the shale gas preservation condition type of the target shale sample according to the standardized content ratio of the target shale sample includes: Determining whether the standardized content ratio of the target shale sample is not greater than a preset threshold; If the standardized content ratio of the target shale sample is not greater than the preset threshold, determining that the shale gas preservation condition type of the target shale sample is normal; If the standardized content ratio of the target shale sample is greater than the preset threshold, it is determined that the shale gas preservation condition type of the target shale sample is abnormal.

9. A terminal 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 computer program, the steps of the method for determining the preservation conditions of highly over-mature shale gas as described in any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method for determining the preservation conditions of highly over-mature shale gas as described in any one of claims 1 to 8 are implemented.

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