Method, device and computer storage medium for determining porosity of shale reservoir

Abstract

The embodiment of the present application discloses a method, device and computer storage medium for determining the porosity of a shale reservoir, and belongs to the technical field of shale gas exploration and development. The method includes: obtaining well logging data of a target single well for a target shale reservoir; determining, in sequence, a first change relationship between the organic carbon content and the reservoir density in the target shale reservoir, and a second change relationship between the organic carbon content and the reservoir volume in the target shale reservoir according to the well logging data; determining the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir according to the first change relationship, the second change relationship and the well logging data. The embodiment of the present application determines the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir through the relationship between the organic carbon content and the reservoir density in the target shale reservoir and the relationship between the organic carbon content and the reservoir volume, thereby improving the accuracy of determining the porosity of the shale reservoir.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of shale gas exploration and development, and in particular to a method, device, and computer storage medium for determining the porosity of a shale reservoir. Background Art

[0002] With the rapid development of shale gas in the global energy sector, its exploration and development are receiving increasing attention. Shale reservoirs vary across regions and wells, with some wells producing high yields, some producing low yields, and some producing no yields. Shale reservoir productivity is related to its porosity, so determining shale porosity is crucial.

[0003] However, because some shale reservoirs have high resistivity and others have low resistivity, that is, when the resistivity is below a certain threshold, the shale reservoir is considered low-resistivity. Currently, the porosity of low-resistivity shale reservoirs is determined using the same method as for normal-resistivity shale reservoirs. This results in inaccurate porosity determinations and, in turn, inaccurate productivity estimates for low-resistivity shale reservoirs. Summary of the Invention

[0004] The embodiments of the present application provide a method, device, and computer storage medium for determining the porosity of a shale reservoir, which can be used to solve the problem of inaccurate porosity determination of low-resistivity shale reservoirs in related technologies.

[0005] The technical solution is as follows:

[0006] In one aspect, a method for determining the porosity of a shale reservoir is provided, the method comprising:

[0007] Obtaining well logging data for a target single well in a target shale reservoir;

[0008] determining, in sequence, based on the well logging data, a first variation relationship between the organic carbon content and the reservoir density in the target shale reservoir, and a second variation relationship between the organic carbon content and the reservoir volume in the target shale reservoir;

[0009] The porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir is determined based on the first change relationship, the second change relationship, and the well logging data.

[0010] In some embodiments, the well logging data includes natural gamma ray logging curves, resistivity curves, acoustic wave transit time curves, and density curves;

[0011] The step of sequentially determining, based on the well logging data, a first variation relationship between the organic carbon content and the reservoir density in the target shale reservoir and a second variation relationship between the organic carbon content and the reservoir volume in the target shale reservoir comprises:

[0012] Determining a logging curve segment corresponding to an organic-rich layer segment and a logging curve segment corresponding to an organic-poor layer segment in the target shale reservoir according to the natural gamma ray logging curve, the resistivity curve, and the acoustic transit time curve;

[0013] Determining an organic carbon content determination model for the target shale reservoir based on the well logging curve segment corresponding to the organic-rich layer segment and the well logging curve segment corresponding to the organic-poor layer segment;

[0014] Performing a linear fit between the inverse of the density curve and the organic carbon content model to obtain the first variation relationship;

[0015] The second change relationship is determined according to the organic carbon content determination model and the first change relationship.

[0016] In some embodiments, determining the logging curve segments corresponding to the organic-rich layer segment and the organic-poor layer segment in the target shale reservoir according to the natural gamma ray logging curve, the resistivity curve, and the acoustic time difference curve includes:

[0017] Overlapping the resistivity curve and the acoustic time difference curve to obtain an overlapping curve;

[0018] According to the position of the curve corresponding to the non-organic layer segment in the natural gamma ray curve, the curve corresponding to the non-organic layer segment in the overlapping curve is removed to obtain the organic overlapping curve;

[0019] The logging curve segment corresponding to the organic-rich layer segment and the logging curve segment corresponding to the organic-poor layer segment are determined from the organic matter overlap curve. The logging curve segment corresponding to the organic-rich layer segment is the logging curve segment in which the resistivity curve and the acoustic time difference curve in the organic matter overlap curve have different trends and do not overlap. The logging curve segment corresponding to the organic-poor layer segment is the logging curve segment in which the resistivity curve and the acoustic time difference curve in the organic matter overlap curve have the same trends and overlap.

[0020] In some embodiments, determining the organic carbon content determination model of the target shale reservoir based on the well logging curve segment corresponding to the organic-rich layer segment and the well logging curve segment corresponding to the organic-poor layer segment includes:

[0021] Obtaining the formation resistivity of the target shale reservoir and the organic carbon content corresponding to different formations;

[0022] Determining an acoustic transit time baseline and a resistivity baseline in the logging curve segment corresponding to the organic-poor layer segment, wherein the acoustic transit time baseline is a baseline corresponding to the acoustic wave in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment, and the resistivity baseline is a baseline corresponding to the resistivity in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment;

[0023] Determining a reference acoustic transit time baseline and a reference resistivity baseline in the logging curve segment corresponding to the organic-rich layer segment based on the acoustic transit time baseline and the resistivity baseline corresponding to the organic-poor layer segment, and determining a reference acoustic transit time curve in the logging curve segment corresponding to the organic-rich layer segment;

[0024] determining reference organic matter abundances corresponding to different strata based on the reference acoustic transit time baseline, the reference resistivity baseline, the reference acoustic transit time curve, and the formation resistivity;

[0025] The organic matter reference abundance corresponding to the different strata and the organic carbon content corresponding to the different strata are linearly fitted to obtain the organic carbon content determination model.

[0026] In some embodiments, determining the second change relationship according to the organic carbon content determination model and the first change relationship includes:

[0027] Determine, from the first variation relationship, the densities corresponding to when the organic carbon content is 0% and 100%, respectively;

[0028] Determine the density corresponding to when the organic carbon content is 0 as the rock skeleton density of the target shale reservoir, and determine the density corresponding to when the organic carbon content is 100% as the density of the organic carbon content;

[0029] The second variation relationship is determined according to the organic carbon content density, the organic carbon content determination model, and reference densities corresponding to different strata, where the reference densities corresponding to different strata are obtained through the density curve.

[0030] In some embodiments, determining the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir based on the first change relationship and the second change relationship includes:

[0031] Determining the formation densities of different formations of the target shale reservoir after eliminating the influence of the organic carbon content based on the second change relationship, the density of the organic carbon content described in the first change relationship, and reference densities corresponding to different formations;

[0032] The porosity of the different formations is determined based on the formation density of the different formations, the rock skeleton density, and the fluid density of the fluid in the target shale reservoir.

[0033] In another aspect, a device for determining the porosity of a shale reservoir is provided, the device comprising:

[0034] An acquisition module, used to acquire well logging data of a target single well for a target shale reservoir;

[0035] a first determining module, configured to sequentially determine, based on the well logging data, a first variation relationship between the organic carbon content and the reservoir density in the target shale reservoir, and a second variation relationship between the organic carbon content and the reservoir volume in the target shale reservoir;

[0036] The second determination module is configured to determine the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir based on the first change relationship, the second change relationship, and the well logging data.

[0037] In some embodiments, the well logging data includes natural gamma ray logging curves, resistivity curves, acoustic wave transit time curves, and density curves;

[0038] The first determining module includes:

[0039] A first determining submodule is configured to determine a logging curve segment corresponding to an organic-rich layer segment and a logging curve segment corresponding to an organic-poor layer segment in the target shale reservoir according to the natural gamma ray logging curve, the resistivity curve, and the acoustic time difference curve;

[0040] A second determination submodule is configured to determine an organic carbon content determination model for the target shale reservoir according to the well logging curve segment corresponding to the organic-rich layer segment and the well logging curve segment corresponding to the organic-poor layer segment;

[0041] a fitting submodule, configured to perform a linear fit between the inverse of the density curve and the organic carbon content model to obtain the first variation relationship;

[0042] The third determination submodule is configured to determine the second change relationship according to the organic carbon content determination model and the first change relationship.

[0043] In some embodiments, the first determining submodule is configured to:

[0044] Overlapping the resistivity curve and the acoustic time difference curve to obtain an overlapping curve;

[0045] According to the position of the curve corresponding to the non-organic layer segment in the natural gamma ray curve, the curve corresponding to the non-organic layer segment in the overlapping curve is removed to obtain the organic overlapping curve;

[0046] The logging curve segment corresponding to the organic-rich layer segment and the logging curve segment corresponding to the organic-poor layer segment are determined from the organic matter overlap curve. The logging curve segment corresponding to the organic-rich layer segment is the logging curve segment in which the resistivity curve and the acoustic time difference curve in the organic matter overlap curve have different trends and do not overlap. The logging curve segment corresponding to the organic-poor layer segment is the logging curve segment in which the resistivity curve and the acoustic time difference curve in the organic matter overlap curve have the same trends and overlap.

[0047] In some embodiments, the second determining submodule is configured to:

[0048] Obtaining the formation resistivity of the target shale reservoir and the organic carbon content corresponding to different formations;

[0049] Determining an acoustic transit time baseline and a resistivity baseline in the logging curve segment corresponding to the organic-poor layer segment, wherein the acoustic transit time baseline is a baseline corresponding to the acoustic wave in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment, and the resistivity baseline is a baseline corresponding to the resistivity in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment;

[0050] Determining a reference acoustic transit time baseline and a reference resistivity baseline in the logging curve segment corresponding to the organic-rich layer segment based on the acoustic transit time baseline and the resistivity baseline corresponding to the organic-poor layer segment, and determining a reference acoustic transit time curve in the logging curve segment corresponding to the organic-rich layer segment;

[0051] determining reference organic matter abundances corresponding to different strata based on the reference acoustic transit time baseline, the reference resistivity baseline, the reference acoustic transit time curve, and the formation resistivity;

[0052] The organic matter reference abundance corresponding to the different strata and the organic carbon content corresponding to the different strata are linearly fitted to obtain the organic carbon content determination model.

[0053] In some embodiments, the third determining submodule is configured to:

[0054] Determine, from the first variation relationship, the densities corresponding to when the organic carbon content is 0% and 100%, respectively;

[0055] Determine the density corresponding to when the organic carbon content is 0 as the rock skeleton density of the target shale reservoir, and determine the density corresponding to when the organic carbon content is 100% as the density of the organic carbon content;

[0056] The second variation relationship is determined according to the organic carbon content density, the organic carbon content determination model, and reference densities corresponding to different strata, where the reference densities corresponding to different strata are obtained through the density curve.

[0057] In some embodiments, the second determining module includes:

[0058] a fourth determination submodule, configured to determine, based on the second change relationship, the density of the organic carbon content described in the first change relationship, and reference densities corresponding to different formations, the formation density of different formations of the target shale reservoir after eliminating the influence of the organic carbon content;

[0059] The fifth determination submodule is configured to determine the porosity of the different formations based on the formation density of the different formations, the rock skeleton density, and the fluid density of the fluid in the target shale reservoir.

[0060] On the other hand, a computer-readable storage medium is provided, on which instructions are stored. When the instructions are executed by a processor, any step of the above-mentioned method for determining the porosity of a shale reservoir is implemented.

[0061] The beneficial effects of the technical solutions provided in the embodiments of the present application include at least:

[0062] In the embodiment of the present application, the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir can be determined through the relationship between the organic carbon content in the target shale reservoir and the reservoir density, as well as the relationship between the organic carbon content and the reservoir volume, thereby improving the accuracy of determining the porosity of the shale reservoir, and further improving the accuracy of the production capacity estimation of the low-resistance shale reservoir. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. 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 any creative work.

[0064] Figure 1 This is a flow chart of a method for determining the porosity of a shale reservoir provided in an embodiment of the present application;

[0065] Figure 2 This is a flow chart of a method for determining the porosity of a shale reservoir provided in an embodiment of the present application;

[0066] Figure 3 This is a schematic diagram of the relationship between the organic carbon content and reservoir density in a target shale reservoir provided in an embodiment of the present application;

[0067] Figure 4 This is a schematic diagram of the relationship between the organic carbon content in a target shale reservoir and the reservoir volume provided in an embodiment of the present application;

[0068] Figure 5 This is a schematic structural diagram of a shale reservoir porosity determination device provided in an embodiment of the present application;

[0069] Figure 6 This is a schematic structural diagram of a first determination module provided in an embodiment of the present application;

[0070] Figure 7 is a structural diagram of a second determination module provided in an embodiment of the present application;

[0071] Figure 8 This is a schematic diagram of the structure of a terminal provided in an embodiment of the present application. DETAILED DESCRIPTION

[0072] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0073] Before explaining in detail a method for determining the porosity of a shale reservoir provided in an embodiment of the present application, an application scenario provided in an embodiment of the present application is first explained.

[0074] Since shale porosity is an important physical property for evaluating shale reservoirs, understanding the porosity in shale reservoirs provides a basis for evaluating the occurrence, flow state, and recoverability of shale oil and shale gas during exploration and development. However, the porosity of low-resistivity shale reservoirs is currently determined using the same method as for normal-resistivity shale reservoirs. This results in inaccurate porosity determinations and, in turn, in inaccurate estimates of the productivity of these reservoirs.

[0075] Based on such an application scenario, an embodiment of the present application provides a method for determining the porosity of a shale reservoir to improve the accuracy of determining the porosity of a low-resistivity shale reservoir.

[0076] Figure 1 This is a flow chart of a method for determining the porosity of a shale reservoir provided in an embodiment of the present application. The method for determining the porosity of a shale reservoir may include the following steps:

[0077] Step 101: Acquire well logging data of a target single well in a target shale reservoir.

[0078] Step 102: Based on the well logging data, determine in sequence a first variation relationship between the organic carbon content in the target shale reservoir and the reservoir density, and a second variation relationship between the organic carbon content in the target shale reservoir and the reservoir volume.

[0079] Step 103: Determine the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir based on the first change relationship, the second change relationship, and the well logging data.

[0080] In the embodiment of the present application, the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir can be determined through the relationship between the organic carbon content in the target shale reservoir and the reservoir density, as well as the relationship between the organic carbon content and the reservoir volume, thereby improving the accuracy of determining the porosity of the shale reservoir, and further improving the accuracy of the production capacity estimation of the low-resistance shale reservoir.

[0081] In some embodiments, the well logging data includes a natural gamma ray log curve, a resistivity curve, a sonic time difference curve, and a density curve;

[0082] Determining, in sequence, based on the well logging data, a first variation relationship between the organic carbon content and the reservoir density in the target shale reservoir, and a second variation relationship between the organic carbon content and the reservoir volume in the target shale reservoir, including:

[0083] Determining a logging curve segment corresponding to an organic-rich layer segment and a logging curve segment corresponding to an organic-poor layer segment in the target shale reservoir according to the natural gamma ray logging curve, the resistivity curve, and the acoustic time difference curve;

[0084] Determine the organic carbon content determination model of the target shale reservoir according to the well logging curve segment corresponding to the organic-rich layer segment and the well logging curve segment corresponding to the organic-poor layer segment;

[0085] Performing a linear fit between the inverse of the density curve and the organic carbon content model to obtain the first variation relationship;

[0086] The second change relationship is determined according to the organic carbon content determination model and the first change relationship.

[0087] In some embodiments, determining the logging curve segments corresponding to the organic-rich layer segment and the organic-poor layer segment in the target shale reservoir based on the natural gamma ray logging curve, the resistivity curve, and the acoustic transit time curve includes:

[0088] Overlapping the resistivity curve and the acoustic time difference curve to obtain an overlapping curve;

[0089] According to the position of the curve corresponding to the non-organic layer segment in the natural gamma ray curve, the curve corresponding to the non-organic layer segment in the overlapping curve is removed to obtain the organic overlapping curve;

[0090] The logging curve segment corresponding to the organic-rich layer segment and the logging curve segment corresponding to the organic-poor layer segment are determined from the organic matter overlap curve. The logging curve segment corresponding to the organic-rich layer segment is the logging curve segment in which the resistivity curve and the acoustic wave time difference curve in the organic matter overlap curve have different trends and do not overlap. The logging curve segment corresponding to the organic-poor layer segment is the logging curve segment in which the resistivity curve and the acoustic wave time difference curve in the organic matter overlap curve have the same trends and overlap.

[0091] In some embodiments, determining the organic carbon content determination model of the target shale reservoir and the well logging curve segment corresponding to the organic-poor layer segment based on the well logging curve segment corresponding to the organic-rich layer segment includes:

[0092] Obtain the formation resistivity of the target shale reservoir and the organic carbon content corresponding to different strata;

[0093] Determining an acoustic transit time baseline and a resistivity baseline in the logging curve segment corresponding to the organic-poor layer segment, wherein the acoustic transit time baseline is a baseline corresponding to the acoustic wave in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment, and the resistivity baseline is a baseline corresponding to the resistivity in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment;

[0094] Determining a reference acoustic transit time baseline and a reference resistivity baseline in the logging curve segment corresponding to the organic-rich layer segment based on the acoustic transit time baseline and the resistivity baseline corresponding to the organic-poor layer segment, and determining a reference acoustic transit time curve in the logging curve segment corresponding to the organic-rich layer segment;

[0095] determining reference organic matter abundances corresponding to different strata based on the reference acoustic transit time baseline, the reference resistivity baseline, the reference acoustic transit time curve, and the formation resistivity;

[0096] The organic matter reference abundance corresponding to the different strata and the organic carbon content corresponding to the different strata are linearly fitted to obtain a model for determining the organic carbon content.

[0097] In some embodiments, determining the second change relationship according to the organic carbon content determination model and the first change relationship includes:

[0098] Determine, from the first variation relationship, the densities corresponding to when the organic carbon content is 0% and 100%, respectively;

[0099] The density corresponding to when the organic carbon content is 0 is determined as the rock skeleton density of the target shale reservoir, and the density corresponding to when the organic carbon content is 100% is determined as the density of the organic carbon content;

[0100] The second variation relationship is determined based on the organic carbon content density, the organic carbon content determination model, and reference densities corresponding to different strata. The reference densities corresponding to different strata are obtained through the density curve.

[0101] In some embodiments, determining the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir based on the first change relationship and the second change relationship includes:

[0102] Determining the formation densities of different strata of the target shale reservoir after eliminating the influence of the organic carbon content based on the second variation relationship, the density of the organic carbon content described in the first variation relationship, and reference densities corresponding to different strata;

[0103] The porosity of the different formations is determined based on the formation density of the different formations, the rock skeleton density, and the fluid density of the fluid in the target shale reservoir.

[0104] All of the above optional technical solutions can be combined in any way to form optional embodiments of the present application, and the embodiments of the present application will not be described in detail one by one.

[0105] Figure 2 This is a flow chart of a method for determining the porosity of a shale reservoir provided in an embodiment of the present application. This embodiment uses the method for determining the porosity of a shale reservoir as an example for explanation, and the method for determining the porosity of a shale reservoir may include the following steps:

[0106] Step 201: The terminal obtains logging data of a target single well in a target shale reservoir.

[0107] Since the logging data of a single well can be related to the porosity of a shale reservoir, in order to determine the porosity of a target shale reservoir, the terminal can obtain the logging data of a target single well for the target shale reservoir. The target shale reservoir can be any low-resistivity shale reservoir, and the target single well can be any single well within the target shale reservoir range.

[0108] As an example, upon receiving an acquisition instruction, the terminal can obtain the logging data of the target single well from a locally stored file. That is, the terminal can obtain and store the logging data of the target single well in advance, and upon receiving the acquisition instruction, obtain the logging data of the target single well from the locally stored file. Alternatively, upon receiving the acquisition instruction, the terminal can also send an acquisition request to other devices, where the acquisition request carries the well identifier of the target well; upon receiving the acquisition request from the terminal, the other devices return the logging data of the target well to the terminal based on the well identifier of the target well, thereby enabling the terminal to obtain the logging data of the target well.

[0109] It should be noted that the acquisition instruction is triggered when the user acts on the terminal through a specified operation, and the specified operation includes voice operation, click operation, sliding operation, etc.

[0110] In some embodiments, the well logging data includes at least a gamma ray log (GR), a resistivity log (Rt), a sonic transit time log, and a density log.

[0111] Step 202: The terminal sequentially determines a first variation relationship between the organic carbon content and the reservoir density in the target shale reservoir, and a second variation relationship between the organic carbon content and the reservoir volume in the target shale reservoir based on the well logging data.

[0112] Since the amount of organic carbon content in the target shale reservoir affects the reservoir density and volume, and thus affects the porosity of the target shale reservoir, the terminal needs to determine the first change relationship between the organic carbon content and the reservoir density in the target shale reservoir, and the second change relationship between the organic carbon content and the reservoir volume in the target shale reservoir based on the logging data.

[0113] As an example, the terminal determines the first change relationship between the organic carbon content and the reservoir density in the target shale reservoir, and the second change relationship between the organic carbon content and the reservoir volume in the target shale reservoir in sequence based on the logging data, and the operation includes at least: determining the logging curve segment corresponding to the organic-rich layer segment and the logging curve segment corresponding to the organic-poor layer segment in the target shale reservoir based on the natural gamma logging curve, the resistivity curve and the acoustic time difference curve; determining the organic carbon content determination model of the target shale reservoir based on the logging curve segment corresponding to the organic-rich layer segment and the logging curve segment corresponding to the organic-poor layer segment; linearly fitting the inverse of the density curve with the organic carbon content model to obtain the first change relationship; determining the second change relationship based on the organic carbon content determination model and the first change relationship.

[0114] Since the layers that affect the porosity of the target shale reservoir are mainly organic layers, the terminal needs to determine the logging curve segments corresponding to the organic-rich layers and the organic-poor layers in the target shale reservoir based on the natural gamma ray logging curve, resistivity curve and acoustic time difference curve.

[0115] As an example, the terminal determines the logging curve segments corresponding to the organic-rich layer segment and the logging curve segments corresponding to the organic-poor layer segment in the target shale reservoir based on the natural gamma ray logging curve, the resistivity curve and the acoustic time difference curve, including: overlapping the resistivity curve and the acoustic time difference curve to obtain an overlapping curve; according to the position of the curve corresponding to the non-organic layer segment in the natural gamma ray curve, the curve corresponding to the non-organic layer segment in the overlapping curve is removed to obtain an organic overlapping curve; determining the logging curve segments corresponding to the organic-rich layer segment and the logging curve segments corresponding to the organic-poor layer segment from the organic overlapping curve, the logging curve segment corresponding to the organic-rich layer segment is the logging curve segment in which the resistivity curve and the acoustic time difference curve in the organic overlapping curve have different trends and do not overlap, and the logging curve segment corresponding to the organic-poor layer segment is the logging curve segment in which the resistivity curve and the acoustic time difference curve in the organic overlapping curve have the same trends and overlap.

[0116] In some embodiments, the terminal overlapping the resistivity curve and the acoustic transit time curve means superimposing the scaled acoustic transit time curve on the resistivity curve in the depth measurement direction, thereby obtaining an overlapping curve.

[0117] It should be noted that the operation of overlapping the resistivity curve and the acoustic wave time difference curve by the terminal can refer to the relevant technology, and the embodiments of the present application will not be described in detail.

[0118] Since the inorganic layer has no effect or almost negligible effect on the porosity of the target shale reservoir, and since the natural gamma curve can reflect different reservoir structures, the terminal can remove the curve corresponding to the inorganic layer in the overlapping curve according to the location of the inorganic layer in the natural gamma curve to obtain the organic overlapping curve.

[0119] In some embodiments, the terminal can identify the curve positions corresponding to non-organic layers such as oil layers and evaporative rocks from the natural gamma curve, and according to the curve positions corresponding to the non-organic layers in the natural gamma curve, remove the curves corresponding to the non-organic layers in the overlapping curves to obtain the organic overlapping curves.

[0120] Since the organic matter overlap curve may include the logging curve segments corresponding to the organic matter-poor layer segment and the logging curve segments corresponding to the organic matter-rich layer segment, the terminal can also determine the logging curve segments corresponding to the organic matter-rich layer segment and the logging curve segments corresponding to the organic matter-poor layer segment from the organic matter overlap curve.

[0121] In some embodiments, the terminal can identify a logging curve segment in an organic matter overlay curve where the resistivity curve and the acoustic transit time curve have the same trend and overlap as a logging curve segment corresponding to an organic-poor layer (typically a non-source rock). Also, a logging curve segment in an organic matter overlay curve where the resistivity curve and the acoustic transit time curve have different trends and do not overlap is identified as a logging curve segment corresponding to an organic-rich layer.

[0122] In some embodiments, the terminal determines the organic carbon content of the target shale reservoir according to the well logging curve segment corresponding to the organic-rich layer segment and the well logging curve segment corresponding to the organic-poor layer segment, and the operation of the determination model includes: obtaining the formation resistivity of the target shale reservoir and the organic carbon content corresponding to different formations; determining the acoustic time difference baseline and the resistivity baseline in the well logging curve segment corresponding to the organic-poor layer segment, the acoustic time difference baseline is the baseline corresponding to the acoustic wave in the overlapping part of the well logging curve segment corresponding to the organic-poor layer segment, and the resistivity baseline is the baseline corresponding to the resistivity in the overlapping part of the well logging curve segment corresponding to the organic-poor layer segment. baseline; according to the acoustic transit time baseline and resistivity baseline corresponding to the organic-poor layer section, the reference acoustic transit time baseline and reference resistivity baseline are determined in the logging curve corresponding to the organic-rich layer section, and the reference acoustic transit time curve in the logging curve section corresponding to the organic-rich layer section is determined; the reference abundance of organic matter corresponding to different formations is determined according to the reference acoustic transit time baseline, the reference resistivity baseline, the reference acoustic transit time curve and the formation resistivity; the reference abundance of organic matter corresponding to different formations and the organic carbon content corresponding to different formations are linearly fitted to obtain a model for determining the organic carbon content.

[0123] Since the organic carbon content corresponding to strata at different depths in the target shale reservoir is different, the terminal needs to obtain the formation resistivity of the target shale reservoir and the organic carbon content corresponding to different strata.

[0124] Since the effect of the organic-poor layer on the porosity is almost negligible, and the resistivity baseline and acoustic transit time baseline in the organic-poor layer are related to the resistivity baseline and acoustic transit time baseline in the organic-rich layer, the terminal can first determine the resistivity baseline and acoustic transit time baseline in the organic-poor layer, and then determine the corresponding reference acoustic transit time baseline and reference resistivity baseline in the logging curve segment corresponding to the organic-rich layer based on the resistivity baseline and acoustic transit time baseline in the organic-poor layer.

[0125] In some embodiments, the terminal can determine the resistivity baseline and the acoustic transit time baseline in the organic-poor layer as a reference resistivity baseline and a reference acoustic transit time baseline corresponding to the organic-rich layer, respectively.

[0126] It should be noted that the reference acoustic transit time curve is any acoustic transit time curve in the logging curve segment corresponding to the organic-rich layer segment.

[0127] In some embodiments, the terminal can determine the reference abundance of organic matter corresponding to different formations using the following first formula based on the reference acoustic wave time difference baseline, the reference resistivity baseline, the reference acoustic wave time difference curve and the formation resistivity.

[0128]

[0129] It should be noted that in the first formula (1) above, index is the reference abundance of organic matter corresponding to different strata, R t is the reference resistivity baseline, Δt is the reference acoustic time difference curve, R bl is the formation resistivity, Δt bl is the reference acoustic time difference baseline, and D is a constant.

[0130] In some embodiments, the terminal performs linear fitting on the organic matter reference abundance corresponding to different strata and the organic carbon content corresponding to different strata, and the obtained organic carbon content determination model can be obtained by the following method: Figure 3 It can be represented by the image shown, and can also be represented by the formula shown by the following second formula.

[0131] TOC=A+B*index (2)

[0132] It should be noted that in the above second formula (2), A and B are both constants, TOC is the organic carbon content, and index is the reference abundance of organic matter corresponding to different strata.

[0133] To determine the first variation relationship between the organic carbon content and reservoir density in the target shale reservoir, the terminal can fit the density curve of the target shale reservoir to the organic carbon content. That is, the terminal linearly fits the inverse of the density curve to the organic carbon content model to obtain the first variation relationship.

[0134] It should be noted that after fitting the organic carbon content model with the inverse of the density curve, the following can be obtained: Figure 4 The first change relationship shown.

[0135] Since the reservoir volume will also change as the organic carbon content and density change, the terminal can determine the model and the first change relationship and the second change relationship based on the organic carbon content.

[0136] In some embodiments, the terminal determines the second change relationship based on the organic carbon content determination model and the first change relationship, and the operation includes: determining the densities corresponding to the organic carbon content of 0 and 100% respectively from the first change relationship; determining the density corresponding to the organic carbon content of 0 as the rock skeleton density of the target shale reservoir, and determining the density corresponding to the organic carbon content of 100% as the density of the organic carbon content; determining the second change relationship based on the organic carbon content density, the organic carbon content determination model and the reference density corresponding to different strata, and the reference density corresponding to different strata is obtained through the density curve.

[0137] Since the first change relationship is the relationship between the organic carbon content and the reservoir density in the target shale reservoir, when the organic carbon content is 0, it means that there is no organic carbon content, and the reservoir density of the target shale reservoir at this time is the rock skeleton density of the target shale reservoir. When the organic carbon content is 100%, it means that there is no other substance, so the reservoir density of the target shale reservoir at this time is the density of the organic carbon content.

[0138] As an example, the terminal determines the second change relationship through the following third formula according to the organic carbon content density, the organic carbon content determination model and the reference density corresponding to different strata.

[0139] V k =(TOC*ρ b *υ) / ρ k (3)

[0140] It should be noted that in the third formula (3), V k is the volume corresponding to different strata (or strata at different depths), TOC is the organic carbon content determined by the second formula (2), ρ b is the reference density corresponding to different strata, ρ k is the density of organic carbon content (i.e. the density corresponding to when the organic carbon content is 100%), υ is a constant, usually taking a value of 1.19.

[0141] Step 203: The terminal determines the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir based on the first change relationship and the second change relationship.

[0142] As an example, the terminal determines the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir based on the first change relationship and the second change relationship, and the operation includes: determining the formation density of different strata of the target shale reservoir after eliminating the influence of the organic carbon content based on the second change relationship, the density of the organic carbon content described in the first change relationship, and the reference density corresponding to different strata; determining the porosity of different strata based on the formation density, rock skeleton density and fluid density of the fluid in the target shale reservoir.

[0143] In some embodiments, the terminal determines the formation density of different formations of the target shale reservoir after eliminating the influence of organic carbon content by the following fourth formula based on the second change relationship, the density of the organic carbon content described in the first change relationship, and the reference density corresponding to different formations.

[0144] ρ bc =(ρ b -V k *ρ k ) / (1-V k ) (4)

[0145] It should be noted that in the fourth formula (4), ρ bc To eliminate the influence of organic carbon content, the formation density of different strata in the target shale reservoir is calculated. k is the volume corresponding to different strata determined by the third formula (second relationship) above, ρ b is the reference density corresponding to different strata, ρ k is the density of organic carbon content.

[0146] In some embodiments, the terminal determines the porosity of different formations using the following fifth formula based on the formation density, rock skeleton density and fluid density of the fluid in the target shale reservoir.

[0147] φ=(ρ ma -ρ bc ) / (ρ ma -ρ f ) (5)

[0148] It should be noted that in the fifth formula (5), φ is the porosity of different strata in the target rock reservoir, ρ bc To eliminate the influence of organic carbon content, the formation density of different layers of the target shale reservoir is: ma is the rock skeleton density of the target shale reservoir, ρ f is the fluid density.

[0149] Step 204: The terminal prompts the porosity of the target shale reservoir through the first prompt information.

[0150] In order to enable the staff to clearly understand the porosity of the target shale reservoir, the terminal can prompt the porosity of the target shale reservoir through the first prompt information after determining the porosity of the target shale reservoir.

[0151] In some embodiments, in order to make the staff understand the difference between the porosity obtained by logging and the actual porosity, the terminal can also compare the porosity obtained by logging with the porosity obtained by the above method, and prompt the comparison result through the second prompt information.

[0152] It should be noted that the first prompt information and the second prompt information can both be prompt information in at least one form such as text, image, video, etc.

[0153] In an embodiment of the present application, the terminal can determine the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir through the relationship between the organic carbon content in the target shale reservoir and the reservoir density, as well as the relationship between the organic carbon content and the reservoir volume, thereby improving the accuracy of determining the porosity of the shale reservoir, and further improving the accuracy of the production capacity estimation of the low-resistance shale reservoir.

[0154] Figure 5 This is a schematic diagram of the structure of a shale reservoir porosity determination device provided in an embodiment of the present application. The shale reservoir porosity determination device can be implemented using software, hardware, or a combination of both. The shale reservoir porosity determination device can include: an acquisition module 501, a first determination module 502, and a second determination module 503.

[0155] An acquisition module 501 is used to acquire well logging data of a target single well in a target shale reservoir;

[0156] A first determining module 502 is configured to sequentially determine a first variation relationship between the organic carbon content and the reservoir density in the target shale reservoir, and a second variation relationship between the organic carbon content and the reservoir volume in the target shale reservoir, based on the well logging data;

[0157] The second determining module 503 is configured to determine the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir according to the first change relationship, the second change relationship, and the well logging data.

[0158] In some embodiments, the well logging data includes natural gamma ray logging curves, resistivity curves, acoustic wave transit time curves, and density curves;

[0159] See also Figure 6 , the first determining module 502 includes:

[0160] The first determining submodule 5021 is configured to determine the logging curve segments corresponding to the organic-rich layer segment and the organic-poor layer segment in the target shale reservoir according to the natural gamma ray logging curve, the resistivity curve, and the acoustic transit time curve;

[0161] The second determination submodule 5022 is configured to determine an organic carbon content determination model for the target shale reservoir based on the well logging curve segment corresponding to the organic-rich layer segment and the well logging curve segment corresponding to the organic-poor layer segment;

[0162] A fitting submodule 5023 is configured to perform a linear fit between the inverse of the density curve and the organic carbon content model to obtain the first variation relationship;

[0163] The third determination submodule 5024 is configured to determine the second change relationship according to the organic carbon content determination model and the first change relationship.

[0164] In some embodiments, the first determining submodule 5021 is configured to:

[0165] Overlapping the resistivity curve and the acoustic time difference curve to obtain an overlapping curve;

[0166] According to the position of the curve corresponding to the non-organic layer segment in the natural gamma ray curve, the curve corresponding to the non-organic layer segment in the overlapping curve is removed to obtain the organic overlapping curve;

[0167] The logging curve segment corresponding to the organic-rich layer segment and the logging curve segment corresponding to the organic-poor layer segment are determined from the organic matter overlap curve. The logging curve segment corresponding to the organic-rich layer segment is the logging curve segment in which the resistivity curve and the acoustic time difference curve in the organic matter overlap curve have different trends and do not overlap. The logging curve segment corresponding to the organic-poor layer segment is the logging curve segment in which the resistivity curve and the acoustic time difference curve in the organic matter overlap curve have the same trends and overlap.

[0168] In some embodiments, the second determining submodule 5022 is configured to:

[0169] Obtaining the formation resistivity of the target shale reservoir and the organic carbon content corresponding to different formations;

[0170] Determining an acoustic transit time baseline and a resistivity baseline in the logging curve segment corresponding to the organic-poor layer segment, wherein the acoustic transit time baseline is a baseline corresponding to the acoustic wave in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment, and the resistivity baseline is a baseline corresponding to the resistivity in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment;

[0171] Determining a reference acoustic transit time baseline and a reference resistivity baseline in the logging curve segment corresponding to the organic-rich layer segment based on the acoustic transit time baseline and the resistivity baseline corresponding to the organic-poor layer segment, and determining a reference acoustic transit time curve in the logging curve segment corresponding to the organic-rich layer segment;

[0172] determining reference organic matter abundances corresponding to different strata based on the reference acoustic transit time baseline, the reference resistivity baseline, the reference acoustic transit time curve, and the formation resistivity;

[0173] The organic matter reference abundance corresponding to the different strata and the organic carbon content corresponding to the different strata are linearly fitted to obtain the organic carbon content determination model.

[0174] In some embodiments, the third determining submodule 5024 is configured to:

[0175] Determine, from the first variation relationship, the densities corresponding to when the organic carbon content is 0% and 100%, respectively;

[0176] Determine the density corresponding to when the organic carbon content is 0 as the rock skeleton density of the target shale reservoir, and determine the density corresponding to when the organic carbon content is 100% as the density of the organic carbon content;

[0177] The second variation relationship is determined according to the organic carbon content density, the organic carbon content determination model, and reference densities corresponding to different strata, where the reference densities corresponding to different strata are obtained through the density curve.

[0178] In some embodiments, see Figure 7 , the second determining module 503 includes:

[0179] a fourth determining submodule 5031, configured to determine, based on the second variation relationship, the density of the organic carbon content described in the first variation relationship, and reference densities corresponding to different formations, the formation density of different formations of the target shale reservoir after eliminating the influence of the organic carbon content;

[0180] The fifth determining submodule 5032 is configured to determine the porosity of the different formations according to the formation density of the different formations, the rock skeleton density, and the fluid density of the fluid in the target shale reservoir.

[0181] In an embodiment of the present application, the terminal can determine the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir through the relationship between the organic carbon content in the target shale reservoir and the reservoir density, as well as the relationship between the organic carbon content and the reservoir volume, thereby improving the accuracy of determining the porosity of the shale reservoir, and further improving the accuracy of the production capacity estimation of the low-resistance shale reservoir.

[0182] It should be noted that the porosity determination device for shale reservoirs provided in the above-mentioned embodiments uses the division of the aforementioned functional modules as an example for illustrative purposes only. In actual applications, the aforementioned functions can be assigned to different functional modules as needed, i.e., the internal structure of the device can be divided into different functional modules to perform all or part of the functions described above. Furthermore, the porosity determination device for shale reservoirs provided in the above-mentioned embodiments and the porosity determination method for shale reservoirs are based on the same concept. The specific implementation process is detailed in the method embodiments and will not be further described here.

[0183] Figure 8 The following is a block diagram of a terminal 800 according to an exemplary embodiment of the present application. Terminal 800 may be a smartphone, tablet computer, MP3 player (Moving Picture Experts Group Audio Layer III), MP4 player (Moving Picture Experts Group Audio Layer IV), laptop computer, or desktop computer. Terminal 800 may also be referred to as user equipment, portable terminal, laptop terminal, desktop terminal, or other similar names.

[0184] Typically, the terminal 800 includes a processor 801 and a memory 802 .

[0185] The processor 801 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 801 may be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), or PLA (Programmable Logic Array). The processor 801 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 801 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 801 may also include an AI (Artificial Intelligence) processor, which is used to process computing operations related to machine learning.

[0186] Memory 802 may include one or more computer-readable storage media, which may be non-transitory. Memory 802 may also include high-speed random access memory and non-volatile memory, such as one or more magnetic disk storage devices or flash memory storage devices. In some embodiments, the non-transitory computer-readable storage medium in memory 802 is used to store at least one instruction, which is executed by processor 801 to implement the porosity determination method for shale reservoirs provided in the method embodiments of this application.

[0187] In some embodiments, terminal 800 may optionally include a peripheral device interface 803 and at least one peripheral device. The processor 801, memory 802, and peripheral device interface 803 may be connected via a bus or signal lines. Each peripheral device may be connected to peripheral device interface 803 via a bus, signal lines, or circuit boards. Specifically, the peripheral device may include at least one of a radio frequency circuit 804, a display screen 805, a camera assembly 806, an audio circuit 807, a positioning assembly 808, and a power supply 809.

[0188] The peripheral device interface 803 can be used to connect at least one I / O (Input / Output)-related peripheral device to the processor 801 and the memory 802. In some embodiments, the processor 801, the memory 802, and the peripheral device interface 803 are integrated on the same chip or circuit board; in some other embodiments, any one or two of the processor 801, the memory 802, and the peripheral device interface 803 can be implemented on separate chips or circuit boards, which is not limited in this embodiment.

[0189] The RF circuit 804 is used to receive and transmit RF (Radio Frequency) signals, also known as electromagnetic signals. The RF circuit 804 communicates with communication networks and other communication devices via electromagnetic signals. The RF circuit 804 converts electrical signals into electromagnetic signals for transmission, or converts received electromagnetic signals into electrical signals. Optionally, the RF circuit 804 includes: an antenna system, an RF transceiver, one or more amplifiers, a tuner, an oscillator, a digital signal processor, a codec chipset, a user identity module card, and the like. The RF circuit 804 can communicate with other terminals via at least one wireless communication protocol. Such wireless communication protocols include, but are not limited to, metropolitan area networks, various generations of mobile communication networks (2G, 3G, 4G, and 5G), wireless local area networks, and / or WiFi (Wireless Fidelity) networks. In some embodiments, the RF circuit 804 may also include circuits related to NFC (Near Field Communication), which is not limited in this application.

[0190] Display screen 805 is used to display a user interface (UI). This UI may include graphics, text, icons, videos, or any combination thereof. When display screen 805 is a touch screen display, it is also capable of collecting touch signals on or above the surface of display screen 805. These touch signals can be input as control signals to processor 801 for processing. In this case, display screen 805 can also be used to provide virtual buttons and / or a virtual keyboard, also known as soft buttons and / or a soft keyboard. In some embodiments, there can be a single display screen 805, located on the front panel of terminal 800. In other embodiments, there can be at least two display screens 805, located on different surfaces of terminal 800 or in a foldable design. In other embodiments, display screen 805 can be a flexible display screen, located on a curved or foldable surface of terminal 800. Furthermore, display screen 805 can be configured as a non-rectangular, irregular shape, i.e., a special-shaped screen. Display screen 805 can be made of materials such as LCD (Liquid Crystal Display) and OLED (Organic Light-Emitting Diode).

[0191] The camera assembly 806 is used to capture images or videos. Optionally, the camera assembly 806 includes a front camera and a rear camera. Typically, the front camera is arranged on the front panel of the terminal, and the rear camera is arranged on the back of the terminal. In some embodiments, there are at least two rear cameras, which are any one of a main camera, a depth of field camera, a wide-angle camera, and a telephoto camera, so as to realize the fusion of the main camera and the depth of field camera to realize the background blur function, the fusion of the main camera and the wide-angle camera to realize panoramic shooting and VR (Virtual Reality) shooting function or other fusion shooting functions. In some embodiments, the camera assembly 806 may also include a flash. The flash can be a monochrome temperature flash or a dual-color temperature flash. A dual-color temperature flash refers to a combination of a warm light flash and a cold light flash, which can be used for light compensation at different color temperatures.

[0192] The audio circuit 807 may include a microphone and a speaker. The microphone is used to collect sound waves from the user and the environment, and convert the sound waves into electrical signals that are input into the processor 801 for processing, or input into the radio frequency circuit 804 to achieve voice communication. For the purpose of stereo sound collection or noise reduction, there may be multiple microphones, each located in different parts of the terminal 800. The microphone may also be an array microphone or an omnidirectional collection microphone. The speaker is used to convert electrical signals from the processor 801 or the radio frequency circuit 804 into sound waves. The speaker may be a traditional thin film speaker or a piezoelectric ceramic speaker. When the speaker is a piezoelectric ceramic speaker, it can not only convert electrical signals into sound waves audible to humans, but also convert electrical signals into sound waves inaudible to humans for purposes such as ranging. In some embodiments, the audio circuit 807 may also include a headphone jack.

[0193] Positioning component 808 is used to locate the current geographic location of terminal 800 to implement navigation or LBS (Location Based Service). Positioning component 808 can be based on the US GPS (Global Positioning System), China's Beidou system, Russia's Greninja system, or the European Union's Galileo system.

[0194] Power supply 809 is used to power various components in terminal 800. Power supply 809 can be AC ​​power, DC power, disposable batteries, or rechargeable batteries. When power supply 809 includes a rechargeable battery, the rechargeable battery can support wired charging or wireless charging. The rechargeable battery can also be used to support fast charging technology.

[0195] In some embodiments, the terminal 800 further includes one or more sensors 810 , including but not limited to: an acceleration sensor 811 , a gyroscope sensor 812 , a pressure sensor 813 , a fingerprint sensor 814 , an optical sensor 815 , and a proximity sensor 816 .

[0196] The accelerometer 811 can detect the magnitude of acceleration along the three coordinate axes of the coordinate system established by the terminal 800. For example, the accelerometer 811 can be used to detect the components of gravity acceleration along the three coordinate axes. The processor 801 can control the display screen 805 to display the user interface in a landscape or portrait view based on the gravity acceleration signal collected by the accelerometer 811. The accelerometer 811 can also be used to collect game or user motion data.

[0197] The gyroscope sensor 812 can detect the orientation and rotation angle of the terminal 800. It can work in conjunction with the accelerometer 811 to collect the user's 3D movements of the terminal 800. Based on the data collected by the gyroscope sensor 812, the processor 801 can implement the following functions: motion sensing (for example, changing the UI based on the user's tilt operation), image stabilization during shooting, game control, and inertial navigation.

[0198] The pressure sensor 813 can be set on the side frame of the terminal 800 and / or the lower layer of the display screen 805. When the pressure sensor 813 is set on the side frame of the terminal 800, it can detect the user's grip signal of the terminal 800, and the processor 801 performs left and right hand recognition or shortcut operations based on the grip signal collected by the pressure sensor 813. When the pressure sensor 813 is set on the lower layer of the display screen 805, the processor 801 controls the operational controls on the UI interface based on the user's pressure operation on the display screen 805. The operational controls include at least one of a button control, a scroll bar control, an icon control, and a menu control.

[0199] The fingerprint sensor 814 is used to collect the user's fingerprint. The processor 801 identifies the user's identity based on the fingerprint collected by the fingerprint sensor 814, or the fingerprint sensor 814 identifies the user's identity based on the collected fingerprint. When the user's identity is recognized as a trusted identity, the processor 801 authorizes the user to perform relevant sensitive operations, such as unlocking the screen, viewing encrypted information, downloading software, making payments, and changing settings. The fingerprint sensor 814 can be set on the front, back, or side of the terminal 800. When a physical button or manufacturer logo is provided on the terminal 800, the fingerprint sensor 814 can be integrated with the physical button or manufacturer logo.

[0200] The optical sensor 815 is used to detect ambient light intensity. In one embodiment, the processor 801 can control the display brightness of the display screen 805 based on the ambient light intensity detected by the optical sensor 815. Specifically, when the ambient light intensity is high, the display brightness of the display screen 805 is increased; when the ambient light intensity is low, the display brightness of the display screen 805 is decreased. In another embodiment, the processor 801 can also dynamically adjust the shooting parameters of the camera assembly 806 based on the ambient light intensity detected by the optical sensor 815.

[0201] Proximity sensor 816, also known as a distance sensor, is typically located on the front panel of terminal 800. Proximity sensor 816 is used to detect the distance between the user and the front of terminal 800. In one embodiment, when proximity sensor 816 detects that the distance between the user and the front of terminal 800 is gradually decreasing, processor 801 controls display screen 805 to switch from the screen-on state to the screen-off state. When proximity sensor 816 detects that the distance between the user and the front of terminal 800 is gradually increasing, processor 801 controls display screen 805 to switch from the screen-off state to the screen-on state.

[0202] Those skilled in the art will understand that Figure 8 The structure shown in the figure does not constitute a limitation on the terminal 800, and the terminal 800 may include more or fewer components than shown in the figure, or combine certain components, or adopt a different component arrangement.

[0203] An embodiment of the present application also provides a non-transitory computer-readable storage medium. When the instructions in the storage medium are executed by the processor of the terminal, the terminal is able to execute the porosity determination method of the shale reservoir provided in the above embodiment.

[0204] An embodiment of the present application also provides a computer program product containing instructions, which, when executed on a terminal, enables the terminal to execute the porosity determination method for a shale reservoir provided in the above embodiment.

[0205] Those skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware, or by a program to instruct the relevant hardware, and the program may be stored in a computer-readable storage medium, which may be a read-only memory, a disk, or an optical disk, etc.

[0206] The above description is only a preferred embodiment of the embodiments of the present application and is not intended to limit the embodiments of the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of this application.

Claims

1. A method for determining the porosity of a shale reservoir, characterized in that: The method comprises: Acquire well logging data of a target single well for a target shale reservoir, wherein the well logging data includes a natural gamma logging curve, a resistivity curve, an acoustic time difference curve, and a density curve; Determining in sequence, based on the well logging data, a first variation relationship between the organic carbon content in the target shale reservoir and the reservoir density, and a second variation relationship between the organic carbon content in the target shale reservoir and the reservoir volume; Determine the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir according to the first change relationship, the second change relationship and the well logging data; Wherein, determining in sequence, based on the well logging data, a first change relationship between the organic carbon content in the target shale reservoir and the reservoir density, and a second change relationship between the organic carbon content in the target shale reservoir and the reservoir volume, comprises: Determine the logging curve segment corresponding to the organic-rich layer segment and the logging curve segment corresponding to the organic-poor layer segment in the target shale reservoir according to the natural gamma logging curve, the resistivity curve and the acoustic time difference curve; Determine a model for determining the organic carbon content of the target shale reservoir according to the well logging curve segment corresponding to the organic-rich layer segment and the well logging curve segment corresponding to the organic-poor layer segment; Performing linear fitting on the inverse of the density curve and the organic carbon content determination model to obtain the first variation relationship; Determine the second change relationship according to the organic carbon content determination model and the first change relationship; The method of determining the organic carbon content of the target shale reservoir according to the well logging curve segment corresponding to the organic-rich layer segment and the well logging curve segment corresponding to the organic-poor layer segment includes: Obtaining the formation resistivity of the target shale reservoir and the organic carbon content corresponding to different formations; Determine an acoustic time difference baseline and a resistivity baseline in the logging curve segment corresponding to the organic-poor layer segment, wherein the acoustic time difference baseline is a baseline corresponding to the acoustic wave in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment, and the resistivity baseline is a baseline corresponding to the resistivity in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment; According to the acoustic transit time baseline and resistivity baseline corresponding to the organic-poor layer section, respectively, a corresponding reference acoustic transit time baseline and reference resistivity baseline are determined in the logging curve section corresponding to the organic-rich layer section, and a reference acoustic transit time curve is determined in the logging curve section corresponding to the organic-rich layer section; Determining reference abundance of organic matter corresponding to different strata according to the reference acoustic wave time difference baseline, the reference resistivity baseline, the reference acoustic wave time difference curve and the formation resistivity; Linearly fitting the organic matter reference abundance corresponding to the different strata and the organic carbon content corresponding to the different strata to obtain the organic carbon content determination model; The reference abundance of organic matter corresponding to different strata is determined according to the reference acoustic time difference baseline, the reference resistivity baseline, the reference acoustic time difference curve and the formation resistivity according to the following formula: （1） Where: is the reference abundance of organic matter corresponding to the different strata, is the reference resistivity baseline, is the reference acoustic wave time difference curve, is the formation resistivity, is the reference acoustic wave time difference baseline, is a constant; The organic matter reference abundance corresponding to the different strata and the organic carbon content corresponding to the different strata are linearly fitted to obtain the organic carbon content determination model according to the following formula: （2） Where: and are constants, is the organic carbon content.

2. The method according to claim 1, characterized in that The step of determining the logging curve segment corresponding to the organic-rich layer segment and the logging curve segment corresponding to the organic-poor layer segment in the target shale reservoir according to the natural gamma logging curve, the resistivity curve and the acoustic time difference curve comprises: Overlapping the resistivity curve and the acoustic time difference curve to obtain an overlapping curve; According to the position of the curve corresponding to the non-organic layer section in the natural gamma logging curve, the curve corresponding to the non-organic layer section in the overlapping curve is removed to obtain the organic overlapping curve; The logging curve segment corresponding to the organic-rich layer segment and the logging curve segment corresponding to the organic-poor layer segment are determined from the organic matter overlap curve. The logging curve segment corresponding to the organic-rich layer segment is the logging curve segment in which the resistivity curve and the acoustic wave time difference curve in the organic matter overlap curve have different trends and do not overlap. The logging curve segment corresponding to the organic-poor layer segment is the logging curve segment in which the resistivity curve and the acoustic wave time difference curve in the organic matter overlap curve have the same trends and overlap.

3. The method according to claim 1, characterized in that The determining the second change relationship according to the organic carbon content determination model and the first change relationship includes: Determine, from the first variation relationship, the densities corresponding to when the organic carbon content is 0% and 100% respectively; The density corresponding to when the organic carbon content is 0 is determined as the rock skeleton density of the target shale reservoir, and the density corresponding to when the organic carbon content is 100% is determined as the density of the organic carbon content; The second variation relationship is determined according to the organic carbon content density, the organic carbon content determination model and reference densities corresponding to different strata, and the reference densities corresponding to different strata are obtained by acquiring the density curve.

4. The method according to claim 3, characterized in that The step of determining the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir according to the first change relationship and the second change relationship includes: Determine the formation density of different formations of the target shale reservoir after eliminating the influence of the organic carbon content according to the second change relationship, the density of the organic carbon content described in the first change relationship, and the reference density corresponding to different formations; The porosity of the different formations is determined based on the formation density of the different formations, the rock skeleton density and the fluid density of the fluid in the target shale reservoir.

5. A device for determining the porosity of a shale reservoir, characterized in that: The device comprises: An acquisition module, used to acquire well logging data of a target single well for a target shale reservoir, wherein the well logging data includes a natural gamma logging curve, a resistivity curve, an acoustic time difference curve and a density curve; A first determination module is used to determine, in sequence, a first change relationship between the organic carbon content in the target shale reservoir and the reservoir density, and a second change relationship between the organic carbon content in the target shale reservoir and the reservoir volume according to the well logging data; A second determination module is used to determine the porosity of the target shale reservoir after eliminating the influence of the organic carbon content in the target shale reservoir according to the first change relationship, the second change relationship and the well logging data; Wherein, the first determining module includes: A first determination submodule is used to determine the logging curve segment corresponding to the organic-rich layer segment and the logging curve segment corresponding to the organic-poor layer segment in the target shale reservoir according to the natural gamma logging curve, the resistivity curve and the acoustic time difference curve; A second determination submodule is used to determine an organic carbon content determination model of the target shale reservoir according to the well logging curve segment corresponding to the organic-rich layer segment and the well logging curve segment corresponding to the organic-poor layer segment; A fitting submodule, used for linearly fitting the inverse of the density curve with the organic carbon content determination model to obtain the first change relationship; A third determination submodule, configured to determine the second change relationship according to the organic carbon content determination model and the first change relationship; The second determining submodule is used for: Obtaining the formation resistivity of the target shale reservoir and the organic carbon content corresponding to different formations; Determine an acoustic time difference baseline and a resistivity baseline in the logging curve segment corresponding to the organic-poor layer segment, wherein the acoustic time difference baseline is a baseline corresponding to the acoustic wave in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment, and the resistivity baseline is a baseline corresponding to the resistivity in the overlapping portion of the logging curve segment corresponding to the organic-poor layer segment; Determining a reference acoustic transit time baseline and a reference resistivity baseline in the logging curve segment corresponding to the organic-rich layer segment according to the acoustic transit time baseline and the resistivity baseline corresponding to the organic-poor layer segment, and determining a reference acoustic transit time curve in the logging curve segment corresponding to the organic-rich layer segment; Determining reference abundance of organic matter corresponding to different strata according to the reference acoustic wave time difference baseline, the reference resistivity baseline, the reference acoustic wave time difference curve and the formation resistivity; Linearly fitting the organic matter reference abundance corresponding to the different strata and the organic carbon content corresponding to the different strata to obtain the organic carbon content determination model; The reference abundance of organic matter corresponding to different strata is determined according to the reference acoustic time difference baseline, the reference resistivity baseline, the reference acoustic time difference curve and the formation resistivity according to the following formula: （1） Where: is the reference abundance of organic matter corresponding to the different strata, is the reference resistivity baseline, is the reference acoustic wave time difference curve, is the formation resistivity, is the reference acoustic wave time difference baseline, is a constant; The organic matter reference abundance corresponding to the different strata and the organic carbon content corresponding to the different strata are linearly fitted to obtain the organic carbon content determination model according to the following formula: （2） Where: and are constants, is the organic carbon content.

6. The device according to claim 5, characterized in that The first determining submodule is used for: Overlapping the resistivity curve and the acoustic time difference curve to obtain an overlapping curve; According to the position of the curve corresponding to the non-organic layer section in the natural gamma logging curve, the curve corresponding to the non-organic layer section in the overlapping curve is removed to obtain the organic overlapping curve; The logging curve segment corresponding to the organic-rich layer segment and the logging curve segment corresponding to the organic-poor layer segment are determined from the organic matter overlap curve. The logging curve segment corresponding to the organic-rich layer segment is the logging curve segment in which the resistivity curve and the acoustic wave time difference curve in the organic matter overlap curve have different trends and do not overlap. The logging curve segment corresponding to the organic-poor layer segment is the logging curve segment in which the resistivity curve and the acoustic wave time difference curve in the organic matter overlap curve have the same trends and overlap.

7. The device according to claim 5, characterized in that The third determining submodule is used for: Determine, from the first variation relationship, the densities corresponding to when the organic carbon content is 0% and 100% respectively; The density corresponding to when the organic carbon content is 0 is determined as the rock skeleton density of the target shale reservoir, and the density corresponding to when the organic carbon content is 100% is determined as the density of the organic carbon content; The second variation relationship is determined according to the organic carbon content density, the organic carbon content determination model and reference densities corresponding to different strata, and the reference densities corresponding to different strata are obtained by acquiring the density curve.

8. The device according to claim 7, characterized in that The second determining module comprises: a fourth determination submodule, configured to determine the formation density of different formations of the target shale reservoir after eliminating the influence of the organic carbon content according to the second change relationship, the density of the organic carbon content described in the first change relationship, and the reference density corresponding to different formations; The fifth determination submodule is used to determine the porosity of the different formations according to the formation density of the different formations, the rock skeleton density and the fluid density of the fluid in the target shale reservoir.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, and when the instructions are executed by a processor, the steps of the method described in any one of claims 1 to 4 are implemented.

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