Quantitative evaluation method for reservoir capacity of tight gas reservoir

Abstract

The invention discloses a quantitative evaluation method for the reservoir capacity of a tight gas reservoir, and relates to the field of petroleum and natural gas engineering. The method comprises the following steps: preparing a standard rock core, and obtaining Young modulus of the rock core, mineral types and mineral Young modulus and mineral percentage content of various minerals; minerals in the standard rock core are classified to obtain dragged minerals, raised minerals and mixed minerals; obtaining the limit Young's modulus and the percentage content of the dragged mineral, the percentage content of the mixed mineral and the percentage content of the drawn mineral of the dragged mineral and the drawn mineral; determining a reservoir capacity index, and evaluating the reservoir capacity of the reservoir corresponding to the standard core; and performing reservoir grading on the reservoir based on the reservoir capacity. The method provided by the invention is simple and feasible, has good adaptability to the mine field, also greatly reduces the test expenditure of the mine field, and has good application prospect and popularization value for similar tight gas reservoirs.

Description

Technical Field

[0001] The present application relates to the field of petroleum and natural gas engineering, and in particular to a quantitative evaluation method for the storage capacity of tight gas reservoirs. Background Art

[0002] Tight gas has become an important strategic resource for increasing reserves and production in various oil fields and supporting high-quality development. my country's tight gas resources are mainly distributed in several large basins in the country, with huge development potential. Finding favorable reservoir sweet spots and conducting comprehensive evaluations to determine the quality of the reservoirs, that is, the material basis and storage capacity of the reservoirs are the primary tasks of exploration, development and reservoir transformation. Comprehensive evaluation of the reservoirs will continue to affect subsequent strategic layout and experimental planning.

[0003] A large amount of coring and on-site testing at the mine has confirmed that compared with the tight oil and gas reservoirs in North America, the domestic continental tight gas reservoirs are highly heterogeneous, with discontinuous sand bodies, alternating sand and mud layers, very dense pore channels, and poor connectivity, which poses greater challenges in the reservoir evaluation process.

[0004] At present, the evaluation methods for the basic storage capacity of tight gas materials mainly include comprehensive evaluation from aspects such as field core sampling experiments, detailed logging interpretation, reservoir sweet spots and quality, CT and nuclear magnetic resonance testing, etc. However, the testing costs are relatively high and the cycle is long. The prediction parameters of the basic storage capacity of reservoir materials are diverse and complex, making it difficult to accurately and quantitatively evaluate. Summary of the invention

[0005] The purpose of the present invention is to provide a quantitative evaluation method for the storage capacity of tight gas reservoirs. The method classifies reservoir minerals based on Young's modulus, a mechanical parameter of single rock minerals, further calculates the percentage of different types of minerals, and quantitatively calculates the storage capacity index based on this to grade the reservoir.

[0006] In a first aspect, an embodiment of the present application provides a quantitative evaluation method for the storage capacity of a tight gas reservoir, comprising: preparing a standard core based on a rock sample, and obtaining physical parameters of the standard core; wherein the physical parameters include the Young's modulus of the core, the type of mineral, and the Young's modulus and percentage content of each type of mineral; dividing the various types of minerals in the standard core into drag minerals, pull-up minerals, and mixed minerals according to the physical parameters; determining the limiting Young's modulus of the drag minerals and the limiting Young's modulus of the pull-up minerals according to the physical parameters; determining the percentage content of the drag minerals, the pull-up minerals, and the mixed minerals in the standard core according to the limiting Young's modulus of the drag minerals and the limiting Young's modulus of the pull-up minerals combined with the physical parameters, respectively, to obtain the percentage content of the drag minerals, the pull-up minerals, and the mixed minerals; determining the storage capacity index of the standard core based on the percentage content of the drag minerals, the pull-up minerals, and the mixed minerals, so as to evaluate the storage capacity of the reservoir corresponding to the standard core.

[0007] In combination with the first aspect, in a possible implementation, obtaining the physical parameters of the standard core includes: performing microscopic measurements on the standard core to obtain the types of minerals in the standard core and the percentage of each mineral; and using a mechanical testing system to obtain the core Young's modulus of the standard core and the mineral Young's modulus of each mineral.

[0008] In combination with the first aspect, in a second possible implementation, the various minerals in the standard core are divided into drag minerals, lifting minerals and mixed minerals according to physical parameters, including: classifying the various minerals in the standard core according to their Young's modulus and the Young's modulus of the core; classifying minerals whose Young's modulus is lower than that of the core as drag minerals; classifying minerals whose Young's modulus is higher than that of the core as lifting minerals; and classifying the mixed part of the lifting minerals and the drag minerals as mixed minerals.

[0009] In combination with the first aspect, in a third possible implementation, the limiting Young's modulus of the drag mineral is the sum of the mineral Young's moduli of all mineral types in the drag mineral; the limiting Young's modulus of the pull-up mineral is the sum of the mineral Young's moduli of all mineral types in the pull-up mineral.

[0010] In combination with the third possible implementation of the first aspect, in a fourth possible implementation, the method for calculating the limiting Young's modulus of the drag mineral includes: ;in, represents the limiting Young's modulus of the drag mineral, Indicates the number of mineral types in the drag mineral. Indicates the type of mineral in the drag mineral i The mineral content, Indicates the type of mineral in the drag mineral i Young's modulus of minerals, ; The calculation method of the limiting Young's modulus of the pull-up mineral includes: ;in, It indicates the limiting Young's modulus of the mineral. Indicates the number of mineral species in the standard core, Indicates the type of mineral in the pull-up mineral i The mineral content, Indicates the type of mineral in the pull-up mineral i Young's modulus of minerals, , Indicates the number of mineral types in the drag mineral.

[0011] In combination with the first aspect, in a fifth possible implementation, the method for calculating the percentage of the drag mineral includes: ;in, Indicates the percentage of drag minerals, represents the Young's modulus of the core, represents the limiting Young's modulus of the drag mineral, Indicates the number of mineral species in the drag mineral; Indicates the type of mineral in the drag mineral i The calculation method of the raised mineral percentage includes: ;in, It means to increase the percentage of minerals. It indicates the limiting Young's modulus of the mineral. Indicates the number of mineral species in the standard core, Indicates the percentage of minerals of mineral type i in the pulled-up mineral; the calculation method of the percentage of mixed minerals includes: ;in, Indicates the percentage of mixed minerals. .

[0012] In combination with the first aspect, in a sixth possible implementation manner, the calculation method of the storage capacity index includes: ;in, represents the storage capacity index of the standard core, Indicates the type of mineral in the drag mineral i The percentage content, Indicates the type of mineral in the pull-up mineral i The percentage content, Indicates the mineral types in the mixed mineral i The percentage content, Indicates the percentage of drag minerals, It means to increase the percentage of minerals. Indicates the percentage of mixed minerals. Indicates the number of mineral types in the drag mineral. Indicates the mineral types in the standard core, .

[0013] In combination with the sixth possible implementation of the first aspect, in a seventh possible implementation, the method for calculating the percentage content of each mineral in the drag mineral includes: ;in, Indicates the type of mineral in the drag mineral i The percentage content, Indicates the percentage of drag minerals, Indicates the type of mineral in the drag mineral; Indicates the type of mineral in the drag mineral i The mineral content, ; The calculation method of the percentage content of each mineral in the raised mineral includes: ;in, Indicates the type of mineral in the pull-up mineral i The percentage content, It means to increase the percentage of minerals. Indicates the type of mineral in the pull-up mineral i The mineral content, Indicates the type of mineral. ; The calculation method of the percentage content of each mineral in the mixed mineral includes: ;in, Indicates the percentage of each mineral in the mixed mineral.

[0014] In combination with the sixth possible implementation of the first aspect, in an eighth possible implementation, the storage capacity of the reservoir corresponding to the evaluation standard core includes: When , the storage capacity of the reservoir is classified as weak; when When , the reservoir storage capacity is classified as medium; when When , the storage capacity of the reservoir is classified as strong.

[0015] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: The present invention proposes a new quantitative evaluation method for the storage capacity of tight gas reservoirs, which solves the technical problems in the prior art that the evaluation method for the storage capacity based on the material basis of tight gas has high testing costs and long testing cycles, and is difficult to accurately and quantitatively evaluate the storage capacity of tight gas reservoirs. The method classifies reservoir minerals based on the Young's modulus, a mechanical parameter of a single rock mineral, and calculates the percentage of different types of minerals, thereby quantitatively calculating the storage capacity index and dividing the reservoir by storage capacity. The calculation process of this method is simple and feasible, and it has good adaptability to mines. At the same time, it greatly reduces the testing expenses of mines, and has better application prospects and promotion value for similar tight gas reservoirs. The reservoir type is divided by the storage capacity index, and combined with the dynamic development of reservoir transformation, which is a qualitative improvement over the previous static evaluation of reservoir storage capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1A flowchart of a method for quantitatively evaluating the storage capacity of a tight gas reservoir provided in an embodiment of the present application; Figure 2 A comparison chart of the core storage capacity index corresponding to the tight gas reservoir evaluation section provided in the embodiment of the present application. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are 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.

[0019] Figure 1 This is a flow chart of a method for quantitatively evaluating the storage capacity of a tight gas reservoir provided in an embodiment of the present application, including steps S1 to S5.

[0020] Step S1: Prepare a standard core based on a rock sample and obtain physical parameters of the standard core. Specifically, the physical parameters include Young's modulus of the core, mineral types, and Young's modulus and mineral percentage of each type of mineral.

[0021] Step S2: Classify various minerals in the standard core into drag minerals, pull-up minerals and mixed minerals according to physical parameters. Specifically, minerals with a Young's modulus lower than that of the core are classified as drag minerals. Minerals with a Young's modulus higher than that of the core are classified as pull-up minerals. The mixed part of pull-up minerals and drag minerals is classified as mixed minerals.

[0022] Step S3: Determine the limiting Young's modulus of the drag mineral and the limiting Young's modulus of the pull mineral according to the physical parameters.

[0023] Step S4: Determine the percentage of the drag mineral, the pull-up mineral and the mixed mineral in the standard core according to the limiting Young's modulus of the drag mineral and the limiting Young's modulus of the pull-up mineral in combination with physical parameters, and obtain the percentage of the drag mineral, the pull-up mineral and the mixed mineral.

[0024] Step S5: Determine the storage capacity index of the standard core based on the drag mineral percentage, the pull mineral percentage and the mixed mineral percentage to evaluate the storage capacity of the reservoir corresponding to the standard core.

[0025] In the embodiment of the present application, reservoir minerals are classified based on the physical parameter Young's modulus of a single rock mineral, and the percentage of different types of minerals is further calculated, so that the storage capacity index can be quantitatively calculated. The storage capacity of the reservoir is divided by the storage capacity index, and it is combined with the dynamic development of reservoir transformation, which can improve the adaptability of the quantitative method of the storage capacity of tight gas reservoirs to the mine, solve the problem that the traditional quantitative method of the storage capacity of tight gas reservoirs consumes a long time and requires a lot of resources for mine testing, and has a qualitative improvement over the previous static evaluation of reservoir storage capacity.

[0026] Specifically, taking the WY area, a main development area of ​​a tight gas reservoir, as an example, a quantitative evaluation process of the tight gas reservoir storage capacity of the WY area is implemented.

[0027] The WY area adopts horizontal well volume fracturing reconstruction. Therefore, the reservoir quality and classification of the WY area are crucial to the selection of fracturing stages and production capacity prediction.

[0028] Among them, WY1 well is a water well in the WY area. The horizontal section of WY1 well is 1500m long and the designed fracturing is 20 sections. Taking the three sections WY1-WY3 as an example, a quantitative evaluation method for the storage capacity of tight gas reservoirs provided in the embodiment of the present application is used to quantitatively evaluate the reservoir types of the three sections WY1-WY3. The specific quantitative evaluation process is shown in steps S1-S5 provided in the embodiment of the present application. Among them, step S1 includes sub-steps 101-103.

[0029] Step 101: Prepare standard cores based on rock samples: For sections WY1-WY3, obtain one rock sample each, for a total of three rock samples, and prepare the rock samples into standard cylindrical standard cores with a height of 5 cm and a bottom diameter of 2.5 cm. The standard core of section WY1 is recorded as Q1, the standard core of section WY2 is recorded as Q2, and the standard core of section WY3 is recorded as Q3.

[0030] Step 102: Using an X-ray diffractometer or other microscopic measurement methods, experiments are performed on the standard core Q1, the standard core Q2, and the standard core Q3 to obtain the mineral types and mineral percentages of the three standard cores, and the results are shown in Table 1. It should be noted that the mineral percentage here refers to the percentage of the mineral in the standard core.

[0031] Table 1

[0032] Step 103: Obtain the core Young's modulus of the three sections of standard core and the mineral Young's modulus of various minerals in the standard core. In the embodiment of the present application, the values ​​of the obtained Young's modulus of the three sections of standard core are shown in Table 1, and the obtained mineral Young's modulus of various minerals in the standard core are shown in Table 2.

[0033] Table 2

[0034] It should be noted that in the embodiments of the present application, the Young's modulus of the core and the Young's modulus of the mineral are obtained through a triaxial rock mechanics testing system.

[0035] Step S2: Classify minerals with a Young's modulus lower than that of the core as drag minerals. Classify minerals with a Young's modulus higher than that of the core as pull-up minerals. Classify a mixture of pull-up minerals and drag minerals as mixed minerals.

[0036] In the embodiment of the present application, the drag minerals include feldspar and clay minerals. The pull minerals include quartz, calcite and dolomite. The mixed minerals include feldspar, clay minerals, quartz, calcite and dolomite.

[0037] Step S3: dragging down the ultimate Young's modulus of the mineral and raising the ultimate Young's modulus of the mineral respectively according to the physical parameters.

[0038] The limiting Young's modulus of the dragging mineral represents the sum of the mineral Young's moduli of all minerals in the dragging mineral. The limiting Young's modulus of the pulling mineral represents the sum of the mineral Young's moduli of all minerals in the pulling mineral.

[0039] Specifically, the calculation formula of the limiting Young's modulus of the drag mineral is as follows: .

[0040] in, represents the limiting Young's modulus of the drag mineral, Indicates the number of mineral types in the drag mineral. Indicates the type of mineral in the drag mineral i The mineral percentage of Indicates the type of mineral in the drag mineral i Young's modulus of minerals, .

[0041] Substituting the values ​​in Table 1 and Table 2 into the above formula for calculation, the limiting Young's modulus of the drag mineral is obtained, as shown in Table 3.

[0042] The calculation process of the ultimate Young's modulus of the pull-up mineral is as follows: .

[0043] in, It indicates the limiting Young's modulus of the mineral. Indicates the number of mineral species in the standard core, Indicates the type of mineral in the pull-up mineral i The mineral content, Indicates the type of mineral in the pull-up mineral i Young's modulus of minerals, .

[0044] Substituting the values ​​in Table 1 and Table 2 into the calculation process of the ultimate Young's modulus of the pulled-up mineral, the ultimate Young's modulus of the pulled-up mineral is obtained, as shown in Table 3.

[0045] Table 3

[0046] Step 4: Based on the limiting Young's modulus of the drag mineral and the limiting Young's modulus of the pull-up mineral combined with physical parameters, the percentage of the drag mineral, the pull-up mineral and the mixed mineral in the standard core are determined respectively to obtain the percentage of the drag mineral, the percentage of the pull-up mineral and the percentage of the mixed mineral.

[0047] The more average the drag mineral percentage, pull-up mineral percentage, and mixed mineral percentage, the better the reservoir homogeneity and storage capacity. The calculation process needs to combine the limiting Young's modulus obtained in Table 3 with the Young's modulus of the actual measured standard core obtained in Table 2. The specific calculation process is as follows: The calculation method of drag mineral percentage includes: .

[0048] in, Indicates the percentage of drag minerals in the standard core. represents the Young's modulus of the standard core, .

[0049] The calculation method of the percentage of the raised minerals includes: .

[0050] in, It means to increase the percentage of minerals. .

[0051] The calculation method of the percentage of mixed minerals includes: .

[0052] in, Indicates the percentage of mixed minerals in the standard core. .

[0053] In summary, the calculation results of the percentage of drag minerals, the percentage of pull minerals and the percentage of mixed minerals are shown in Table 4.

[0054] Table 4

[0055] Step 5: Determine the storage capacity index of the standard core based on the percentage of drag minerals, the percentage of pull minerals and the percentage of mixed minerals to evaluate the storage capacity of the reservoir corresponding to the standard core. Specifically include: Step 501: Calculate the percentage of each mineral in the drag mineral, the pull mineral and the mixed mineral. The specific calculation process is as follows: The calculation process of the percentage of each mineral in the drag mineral includes: .

[0056] in, Drag mineral types within the mineral i The percentage content, .

[0057] The calculation process of the percentage of each mineral in the pull-up mineral includes: .

[0058] in, Indicates the type of mineral in the pull-up mineral i The percentage content, .

[0059] The calculation process of the percentage of each mineral in the mixed mineral includes: .

[0060] Right now: .

[0061] in, Indicates the mineral types in the mixed mineral i The percentage content.

[0062] It should be noted that it is necessary to distinguish the mineral percentage of the minerals in the standard core obtained in step 102 from the mineral percentage of the minerals in the standard core obtained in step 501. , and The mineral content obtained in step 102 is the percentage of the mineral in the entire standard core. , Kazunori They respectively represent the percentage of minerals in the drag minerals, the percentage of minerals in the pull minerals, and the percentage of minerals in the mixed minerals in the standard core.

[0063] Substituting the data in Table 1 and Table 4 into the above three formulas for calculation, the percentage of each mineral in the drag mineral, pull-up mineral and mixed mineral in the standard core is obtained, as shown in Table 5.

[0064] Table 5

[0065] Taking the standard core Q1 in Table 5 as an example, the percentage of feldspar in the drag minerals is 14%, and the percentage of feldspar in the mixed minerals is 8%. Therefore, in the standard core Q1, the proportion of feldspar in the whole standard core Q1 is 22%, which is the same as the percentage of feldspar in the standard core in Table 1 (22%).

[0066] Step 502: Calculate the storage capacity index of the standard cores. Substituting the data in Tables 1 to 5 into the following formula, the storage capacity indexes of the standard cores Q1, Q2 and Q3 are obtained.

[0067] .

[0068] in, Represents the storage capacity index of standard core.

[0069] Specifically, the storage capacity indexes of the standard core Q1, the standard core Q2, and the standard core Q3 are shown in Table 5. The storage capacity index of the standard core Q1 = 0.88, the storage capacity index of the standard core Q2 = 0.84, and the storage capacity index of the standard core Q3 = 0.84.

[0070] Step 503: Based on the storage capacity index, the storage capacity of the reservoir corresponding to the standard core is evaluated, and the storage capacity of the reservoir corresponding to the standard core is divided.

[0071] Step 503: Based on the storage capacity index, the storage capacity of the reservoir corresponding to the standard core is evaluated.

[0072] Specifically, based on the storage capacity index obtained in step 502 , the storage capacity of the reservoirs corresponding to the standard cores Q1, Q2 and Q3 is evaluated.

[0073] when When , the storage capacity of the reservoir is classified as weak.

[0074] when When the reservoir capacity is classified as medium.

[0075] when When , the storage capacity of the reservoir is classified as strong.

[0076] It should be noted that, in the embodiment of the present application, the reservoir is also classified based on the reservoir capacity index, as follows: when When the reservoir capacity is determined to be Class III, the reservoir corresponding to the standard core is determined to be a low-development reservoir.

[0077] when When the reservoir capacity is determined to be Class II, the reservoir corresponding to the standard core is determined to be a medium development reservoir.

[0078] when When the reservoir capacity is determined to be Class I, the reservoir corresponding to the standard core is determined to be a high-development reservoir.

[0079] In the embodiment of the present application, the reservoir type corresponding to the standard cores Q1, Q2, and Q3 is Class I, and the reservoir quality is roughly the same. They are high-development reservoirs and need to be strengthened and transformed.

[0080] It should be noted that the quantitative evaluation method for the storage capacity of a tight gas reservoir provided in the present application also includes combining the calculated storage capacity index with the dynamic development of reservoir transformation to guide the exploration and development of the tight gas reservoir.

[0081] Although the present application provides method operation steps as described in the embodiments or flowcharts, more or fewer operation steps may be included based on conventional or non-creative labor. The order of steps listed in this embodiment is only one way of executing the order of many steps and does not represent the only execution order. When the actual device or client product is executed, it can be executed in sequence or in parallel according to the method shown in this embodiment or the accompanying drawings (for example, in a parallel processor or multi-threaded processing environment).

[0082] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other. Each embodiment focuses on the differences from other embodiments.

[0083] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit the present application. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present application.

Claims

1. A quantitative evaluation method for storage capacity of tight gas reservoirs, characterized in that: include: Prepare a standard core based on the rock sample and obtain physical parameters of the standard core; wherein the physical parameters include Young's modulus of the core, mineral types, and Young's modulus and mineral percentage of each type of mineral; According to physical parameters, various minerals in standard cores are divided into drag minerals, pull-up minerals and mixed minerals; Determine the limiting Young's modulus of the drag mineral and the limiting Young's modulus of the pull mineral based on the physical parameters; Based on the limiting Young's modulus of the drag mineral and the limiting Young's modulus of the pull-up mineral combined with the physical parameters, the percentage of the drag mineral, the pull-up mineral and the mixed mineral in the standard core are determined respectively, and the percentage of the drag mineral, the pull-up mineral and the mixed mineral are obtained; The storage capacity index of the standard core is determined based on the percentage of drag minerals, the percentage of pull-up minerals and the percentage of mixed minerals to evaluate the storage capacity of the reservoir corresponding to the standard core.

2. The method according to claim 1, characterized in that The physical parameters of the standard core are obtained, including: Conduct microscopic measurement on the standard core to obtain the mineral types and percentage content of each mineral in the standard core; The Young's modulus of the standard core and the Young's modulus of various minerals are obtained by using the mechanical testing system.

3. The method according to claim 1, characterized in that The various minerals in the standard core are divided into drag minerals, pull-up minerals and mixed minerals according to physical parameters, including: Classify various minerals in the standard core according to their Young's modulus and the Young's modulus of the core; Minerals with Young's modulus lower than that of the core are classified as drag minerals; Minerals with Young's modulus higher than that of the core are classified as pull-up minerals; The mixed part of the pull-up minerals and the drag-down minerals is classified as mixed minerals.

4. The method according to claim 1, characterized in that The limiting Young's modulus of the encumbered mineral is the sum of the Young's moduli of all mineral species in the encumbered mineral; The limiting Young's modulus of the pulled-up mineral is the sum of the Young's moduli of all mineral types in the pulled-up mineral.

5. The method according to claim 4, characterized in that The calculation method of the limiting Young's modulus of the drag mineral includes: ； in, represents the limiting Young's modulus of the drag mineral, Indicates the number of mineral types in the drag mineral. Indicates the type of mineral in the drag mineral i The mineral content, Indicates the type of mineral in the drag mineral i Young's modulus of minerals, ; The method for calculating the limiting Young's modulus of the pull-up mineral includes: ； in, It indicates the limiting Young's modulus of the mineral. Indicates the number of mineral species in the standard core, Indicates the type of mineral in the pull-up mineral i The mineral content, Indicates the type of mineral in the pull-up mineral i Young's modulus of minerals, , Indicates the number of mineral types in the drag mineral.

6. The method according to claim 1, characterized in that The method for calculating the percentage of drag minerals includes: ； in, Indicates the percentage of drag minerals, represents the Young's modulus of the core, represents the limiting Young's modulus of the drag mineral, Indicates the number of mineral species in the drag mineral; Indicates the type of mineral in the drag mineral i The mineral percentage of The calculation method of the percentage of the raised mineral includes: ； in, It means to increase the percentage of minerals. It indicates the limiting Young's modulus of the mineral. Indicates the number of mineral species in the standard core, Indicates the type of mineral in the pull-up mineral i The mineral percentage of The calculation method of the percentage of mixed minerals includes: ； in, Indicates the percentage of mixed minerals. .

7. The method according to claim 1, characterized in that The calculation method of the storage capacity index includes: ； in, represents the storage capacity index of the standard core, Indicates the type of mineral in the drag mineral i The percentage content, Indicates the type of mineral in the pull-up mineral i The percentage content, Indicates the mineral types in the mixed mineral i The percentage content, Indicates the percentage of drag minerals, It means to increase the percentage of minerals. Indicates the percentage of mixed minerals. Indicates the number of mineral types in the drag mineral. Indicates the number of mineral species in the standard core, .

8. The method according to claim 7, characterized in that The above indicates the type of mineral in the drag mineral i The calculation method of percentage content includes: ； in, Indicates the type of mineral in the drag mineral i The percentage content, Indicates the percentage of drag minerals, Indicates the number of mineral species in the drag mineral; Indicates the type of mineral in the drag mineral i The mineral percentage of The calculation method of the percentage content of each mineral in the pull-up mineral includes: ； in, Indicates the type of mineral in the pull-up mineral i The percentage content, It means to increase the percentage of minerals. Indicates the type of mineral in the pull-up mineral i The mineral content, Indicates the number of mineral species; The mineral types in the mixed minerals i The calculation method of percentage content includes: ； in, Indicates the percentage of each mineral in the mixed mineral. .

9. The method according to claim 7, characterized in that: The storage capacity of the reservoir corresponding to the evaluation standard core includes: when When , the storage capacity of the reservoir is classified as weak; when When , the storage capacity of the reservoir is classified as medium; when When , the storage capacity of the reservoir is classified as strong.

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