Reef indication factor construction and well-free area reef prediction method

Abstract

The embodiment of the invention discloses a reef indication factor construction method and a well-free area reef prediction method. The method comprises the following steps: acquiring logging data and a logging interpretation result of a target stratum; wherein the target stratum comprises a carbonate rock stratum and a clastic rock stratum; constructing a reef indication factor curve and determining a reef indication factor angle according to the logging data and the logging interpretation result of the carbonate rock stratum; wherein the carbonate rock stratum comprises a reef body; and constructing a geologic model and an attribute model of the target stratum, performing forward modeling to generate a synthetic gather, and performing inversion on the synthetic gather to verify the reef indication factor curve. By adopting the scheme, the reef indication factor curve capable of accurately predicting reef distribution is constructed according to the stratum logging data and the logging interpretation result, and the reef indication factor curve is verified through synthetic gather inversion, so that the existence of the reef can be accurately predicted by determining the reef indication factor curve; and a good foundation is laid for exploration and development of oil and gas reservoirs.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of special processing of seismic data, and in particular, to a method for constructing reef indication factors and predicting reefs in well - less areas. Background Art

[0002] There are many reefs in the Quaternary basins of our country. Since most of their internal structures are relatively loose and pores are developed, they become good oil and gas reservoirs and are favorable targets for the exploration and development of lithologic oil and gas reservoirs. Reef prediction is one of the important topics in geological and geophysical research.

[0003] The existing reef prediction technologies mainly analyze the core, logging, well - logging data and seismic data of the existing wells drilled through reefs, and with the help of rock physics analysis and seismic forward modeling technical means, understand the well - logging, elastic parameters, AVO response characteristics and seismic reflection characteristics of reefs, establish reef interpretation markers for seismic stacking profiles, AVO attribute profiles and pre - stack lithologic inversion profiles, and implement the spatial distribution of reefs. In areas with low exploration degree, there are no drilling data at all, and the seismic data are mainly two - dimensional data. It is impossible to carry out reef prediction by conventional methods. Only based on the reflection structure and shape on the seismic profile, the paleogeomorphic position, and the reflection amplitude and frequency characteristics, etc., the shape and distribution range of reefs are speculated. However, because the seismic reflection characteristics of reefs and thick - layer sandstones on the seismic profile are similar, with strong amplitude and low frequency, and sometimes their tectonic positions are quite the same, it is more difficult to identify them, and the reliability of reef prediction is significantly low.

[0004] Therefore, how to predict reefs in well - less areas is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0005] The embodiments of the present invention provide a method for constructing reef indication factors and predicting reefs in well - less areas, so as to accurately predict the existence of reefs through reef indication factor curves in the strata of well - less areas, and lay a good foundation for the exploration and development of oil and gas reservoirs.

[0006] In a first aspect, the embodiments of the present invention provide a method for constructing reef indication factors, including:

[0007] Obtain the well - logging data and well - logging interpretation results of the target formation; wherein, the target formation includes carbonate strata and clastic rock strata;

[0008] Based on the well - logging data and well - logging interpretation results of the carbonate strata, construct a reef indication factor curve and determine the reef indication factor angle; wherein, the reef indication factor curve is used to characterize the existence of reefs, and the carbonate strata include reefs;

[0009] Construct a geological model and an attribute model of the target formation, perform forward modeling to generate a synthetic gather, and perform inversion on the synthetic gather to verify the reef indication factor curve.

[0010] In a second aspect, an embodiment of the present invention provides a reef prediction method for a well - less area, including:

[0011] Obtain common - reflection - point gather data of the formation in the well - less area, and analyze the common - reflection - point gather data to generate an attribute data volume;

[0012] Analyze the attribute data volume to determine a P - wave impedance data volume and an S - wave impedance data volume;

[0013] Determine a reef - indicating factor data volume based on the P - wave impedance data volume, the S - wave impedance data volume, and the reef - indicating factor angle;

[0014] Predict reefs in the formation of the well - less area based on the reef - indicating factor data volume.

[0015] In a third aspect, an embodiment of the present invention further provides a device for constructing a reef - indicating factor, including:

[0016] A logging data acquisition module, configured to acquire logging data and logging interpretation results of a target formation; wherein, the target formation includes a carbonate formation and a clastic rock formation;

[0017] A reef - indicating factor construction module, configured to construct a reef - indicating factor curve and determine a reef - indicating factor angle based on the logging data and logging interpretation results of the carbonate formation; wherein, the reef - indicating factor curve is used to characterize the presence of reefs, and the carbonate formation includes reefs;

[0018] A reef - indicating factor verification module, configured to construct a geological model and an attribute model of the target formation, perform forward modeling to generate a synthetic gather, and perform inversion on the synthetic gather to verify the reef - indicating factor curve.

[0019] In a fourth aspect, an embodiment of the present invention further provides a device for predicting reefs in a well - less area, including:

[0020] A gather data analysis module, configured to obtain common - reflection - point gather data of the formation in the well - less area, and analyze the common - reflection - point gather data to generate an attribute data volume;

[0021] An impedance data volume determination module, configured to analyze the attribute data volume to determine a P - wave impedance data volume and an S - wave impedance data volume;

[0022] A reef - indicating factor data volume determination module, configured to determine a reef - indicating factor data volume based on the P - wave impedance data volume, the S - wave impedance data volume, and the reef - indicating factor angle;

[0023] A reef body prediction module for well - less areas, which is used to predict reef bodies in the strata of well - less areas based on the reef body indicator factor data volume.

[0024] In a fifth aspect, an embodiment of the present invention further provides an electronic device, which includes:

[0025] One or more processors;

[0026] A storage device for storing one or more programs;

[0027] When the one or more programs are executed by the one or more processors, the one or more processors implement the reef body indicator factor construction and well - less area reef body prediction method according to any embodiment of the present invention.

[0028] In a sixth aspect, an embodiment of the present invention further provides a computer - readable storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the reef body indicator factor construction and well - less area reef body prediction method according to any embodiment of the present invention.

[0029] In a seventh aspect, an embodiment of the present invention further provides a computer program product, including a computer program. When the computer program is executed by a processor, it implements the reef body indicator factor construction and well - less area reef body prediction method according to any embodiment of the present invention.

[0030] An embodiment of the present invention provides a reef body indicator factor construction and well - less area reef body prediction method. By obtaining well - logging data and well - logging interpretation results of carbonate strata and clastic rock strata; based on the well - logging data and well - logging interpretation results of carbonate strata, constructing a reef body indicator factor curve for characterizing the presence of reef bodies and determining the reef body indicator factor angle; constructing a geological model and an attribute model of the target formation and performing forward modeling to generate a synthetic gather, and performing inversion on the synthetic gather to verify the reef body indicator factor curve. By adopting the technical solution of the embodiment of the present invention, according to the formation well - logging data and well - logging interpretation results, a reef body indicator factor curve capable of accurately predicting the distribution of reef bodies is constructed, and the reef body indicator factor curve is verified through synthetic gather inversion to determine that the reef body indicator factor curve can accurately predict the presence of reef bodies, laying a good foundation for the exploration and development of oil and gas reservoirs. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] By reading the following detailed description of non - restrictive embodiments with reference to the accompanying drawings, other features, objects, and advantages of the present invention will become more apparent. The drawings are only for the purpose of showing the preferred embodiments and are not considered as limiting the present invention. Moreover, throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0032] Figure 1It is a flowchart of a method for constructing reef indication factors provided in an embodiment of the present invention;

[0033] Figure 2 It is a flowchart of another method for constructing reef indication factors provided in an embodiment of the present invention;

[0034] Figure 3 It is a schematic diagram of the logging response characteristics profile of different lithologies provided in an embodiment of the present invention;

[0035] Figure 4 It is a schematic diagram of the principle of a method for obtaining reef indication factors provided in an embodiment of the present invention;

[0036] Figure 5 It is a schematic diagram of the forward geological and attribute models of the vertical distribution of different lithologies provided in an embodiment of the present invention;

[0037] Figure 6 It is a schematic diagram of the forward synthetic seismogram and its inversion profile of a theoretical model provided in an embodiment of the present invention;

[0038] Figure 7 It is a flowchart of a method for predicting reefs in well - less areas provided in an embodiment of the present invention;

[0039] Figure 8 It is a schematic diagram of the predicted profile of formation reefs in well - less areas provided in an embodiment of the present invention;

[0040] Figure 9 It is a schematic diagram of the structure of a device for constructing reef indication factors provided in an embodiment of the present invention;

[0041] Figure 10 It is a schematic diagram of the structure of a device for predicting reefs in well - less areas provided in an embodiment of the present invention;

[0042] Figure 11 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed implementation manners

[0043] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. Additionally, it should be noted that for the convenience of description, only parts related to the present invention are shown in the drawings, rather than all structures.

[0044] Before discussing the exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although the flowcharts depict operations (or steps) as sequential processes, many of the operations (or steps) can be implemented in parallel, concurrently, or simultaneously. In addition, the order of the operations can be rearranged. The process can be terminated when its operations are completed, but it can also have additional steps not included in the drawings. The process can correspond to a method, function, procedure, subroutine, subprogram, and so on.

[0045] Among them, the acquisition, storage, use, and processing of data in the technical solution of this application all comply with the relevant regulations of national laws and regulations. It should be noted that in the embodiments of this application, some industry-existing solutions such as certain software, components, or models may be mentioned. They should be considered exemplary. The purpose is only to illustrate the feasibility in the implementation of the technical solution of this application, but it does not mean that the applicant has already or necessarily used this solution.

[0046] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here.

[0047] Embodiment 1

[0048] Figure 1 It is a flowchart of a method for constructing a reef body indication factor provided in an embodiment of the present invention. This embodiment is applicable to the situation of constructing a reef body indication factor based on logging data. The method of this embodiment can be executed by a reef body indication factor construction device, and this device can be implemented in a hardware and / or software manner. This device can be configured in a server for constructing a reef body indication factor. The method specifically includes the following steps:

[0049] S110. Obtain the logging data and logging interpretation results of the target formation.

[0050] Among them, the target formation includes carbonate formations and clastic rock formations. A reef body is a special type in carbonate formations. In the embodiments of the present invention, a reef body indication factor that can indicate the existence of a reef body is constructed based on the logging data and logging interpretation results of carbonate formations. A clastic rock formation can refer to a rock formation formed by the mechanical weathering of rocks into rock debris and mineral debris, which are transported, deposited, compacted, and cemented.

[0051] Well logging data are records of physical parameters of underground rock formations obtained through geophysical well logging techniques, and are important bases for oil and gas exploration, reservoir evaluation, and geological research. The well logging data include, but are not limited to, natural gamma, spontaneous potential, resistivity, density, longitudinal wave and shear wave acoustic travel times.

[0052] Well logging interpretation results can be useful geological information obtained by analyzing, calculating, and studying the geophysical data of rock formations measured along a borehole profile. The well logging interpretation results include, but are not limited to, shale content and porosity.

[0053] S120. Based on the well logging data and well logging interpretation results of carbonate rock formations, construct a reef body indicator factor curve and determine the reef body indicator factor angle.

[0054] Among them, the reef body indicator factor curve is used to characterize the presence of a reef body. Since carbonate rock formations include reef bodies, in the embodiments of the present invention, a reef body indicator factor curve is constructed based on the well logging data and well logging interpretation results of carbonate rock formations to characterize the presence of a reef body.

[0055] The reef body indicator factor angle refers to the angle corresponding to the reef body indicator factor curve, and the reef body indicator factor curve obtained at this angle can characterize the presence of a reef body.

[0056] In the embodiments of the present invention, through the well logging data and well logging interpretation results of carbonate rock formations, summarize the well logging response characteristics of reef bodies, and optimize the sensitive well logging curves of reef body formations; determine the well logging curves related to the angle through the Connolly formula, and perform correlation calculation on the well logging curves related to the angle and the optimized sensitive curves of reef body formations to determine the reef body indicator factor curve and determine the corresponding reef body indicator factor angle.

[0057] S130. Construct a geological model and an attribute model of the target formation and perform forward modeling to generate a synthetic gather, and perform inversion on the synthetic gather to verify the reef body indicator factor curve.

[0058] Among them, the geological model can refer to a model constructed based on the formation thickness and longitudinal distribution sequence of carbonate rock formations and clastic rock formations. The attribute model can refer to a model constructed based on the longitudinal wave velocity, shear wave velocity, and density of carbonate rock formations and clastic rock formations. Through the geological model and the attribute model, the formation characteristics of carbonate rock formations and clastic rock formations can be better simulated.

[0059] The synthetic gather can refer to a set of seismic data simulated and generated through certain physical models and mathematical methods in seismic data processing. These data are usually used to simulate the propagation of seismic waves in underground media in order to better understand and interpret actual seismic data.

[0060] In the embodiment of the present invention, multiple groups of seismic data of carbonate strata and clastic rock strata are simulated into synthetic seismograms through a geological model and an attribute model; and the simulated synthetic seismograms are inverted to verify the reef indicator factor curve. For example, a larger value in the reef indicator factor curve indicates that the formation position is a reef. By comparing the inversion result of the synthetic seismogram with the reef indicator factor curve, it is determined that the reef position indicated by the reef indicator factor curve is basically the same as the reef position indicated by the inversion result of the synthetic seismogram, and thus the reef indicator factor curve can be verified.

[0061] The embodiment of the present invention provides a method for constructing a reef indicator factor. By obtaining well logging data and well logging interpretation results of a target formation; wherein, the target formation includes carbonate strata and clastic rock strata; according to the well logging data and well logging interpretation results of the carbonate strata, a reef indicator factor curve is constructed and the reef indicator factor angle is determined; wherein, the reef indicator factor curve is used to characterize the existence of a reef, and the carbonate strata include reefs; a geological model and an attribute model of the target formation are constructed and forward modeling is performed to generate synthetic seismograms, and the synthetic seismograms are inverted to verify the reef indicator factor curve. By adopting the technical solution of the embodiment of the present invention, a reef indicator factor curve that can accurately predict the distribution of reefs is constructed based on formation well logging data and well logging interpretation results, and the reef indicator factor curve is verified through synthetic seismogram inversion to determine that the reef indicator factor curve can accurately predict the existence of reefs, laying a good foundation for the exploration and development of oil and gas reservoirs.

[0062] Embodiment 2

[0063] Figure 2 It is a flowchart of another method for constructing a reef indicator factor provided in the embodiment of the present invention. The embodiment of the present invention further optimizes the foregoing embodiment on the basis of the above embodiment, and the embodiment of the present invention can be combined with each optional solution in one or more of the above embodiments. As Figure 2 shown, the method for constructing a reef indicator factor and predicting reefs in a well - less area provided in the embodiment of the present invention may include the following steps:

[0064] S210. Obtain well logging data and well logging interpretation results of the target formation.

[0065] S220. According to the well logging data and well logging interpretation results of the carbonate strata, determine the carbonate well logging response characteristics and determine the first well logging curve.

[0066] Among them, the logging response characteristics refer to the relationship between the formation information obtained through various logging methods (such as natural gamma logging, array induction logging, etc.) and the actual physical properties of the formation. These characteristics are of great significance for identifying formation types, evaluating reservoir properties, and predicting oil and gas reservoirs. The logging response characteristics include but are not limited to natural gamma, spontaneous potential, resistivity, longitudinal wave velocity, shear wave velocity, density, and porosity, etc. Refer to Table 1 for the logging response characteristics of different lithologic formations obtained.

[0067] Table 1 List of Logging Response Characteristics of Different Lithologies

[0068]

[0069] Among them, the first logging curve is used to characterize the sensitive curve of carbonate rock formations and is a curve selected from the logging response characteristic curves that can characterize the characteristics of carbonate rock formations. For example, refer to Figure 3 , based on the logging response characteristic profile of different lithologies, select the logging curve that can clearly indicate the existence of reef bodies. For example, the resistivity curve can be selected as the first logging curve.

[0070] S230. Determine the longitudinal wave impedance and shear wave impedance of the target formation, and determine at least two second logging curves based on elastic impedance inversion.

[0071] Among them, elastic impedance inversion is a seismic inversion technique that combines conventional acoustic impedance inversion and prestack AVO (Amplitude Versus Offset) inversion. It has the characteristics of rich information, high resolution, and can reach the level of quantitative analysis, and at the same time has a relatively fast calculation speed. The second logging curves are obtained through elastic impedance inversion at different angles. The Connolly elastic impedance formula is an important part of the elastic impedance inversion technique. In the embodiments of the present invention, at least two second logging curves are determined through the Connolly elastic impedance formula.

[0072] The Connolly elastic impedance formula can be expressed as:

[0073] L(θ) = AI cos θ + SI sin θ

[0074] Among them, AI represents the longitudinal wave impedance of the target formation; SI represents the shear wave impedance of the target formation; θ increases by 1 to calculate 360 L(θ) curves, that is, 360 second logging curves.

[0075] Among them, the longitudinal wave impedance is determined based on the longitudinal wave velocity and density of the target formation, and the shear wave impedance is determined based on the shear wave velocity and density of the target formation. Therefore, when determining the second logging curves, it is necessary to first determine the shear wave velocity, longitudinal wave velocity, and density of the target formation. The longitudinal wave impedance and longitudinal wave impedance can be expressed as:

[0076] AI = V P *ρ

[0077] SI = V S *ρ

[0078] Wherein, V S represents the shear wave velocity, V P represents the compressional wave velocity, and ρ represents density

[0079] S240. Calculate the correlation between each of the at least two second logging curves and the first logging curve to determine a third logging curve, and use the third logging curve as the reef body indication factor curve.

[0080] Wherein, calculating the correlation between the first logging curve and the second logging curves to determine a third logging curve, and the third logging curve is the logging curve with the highest correlation with the first logging curve selected from the second logging curves. For example, see Figure 4 , calculate the correlation between 360 second logging curves and the first logging curve respectively, and construct a correlation curve as shown in Figure 4 ; through the correlation calculation result curve, the point with the maximum correlation can be determined. For example, the correlation is the maximum at 329 degrees. Determine the second logging curve corresponding to 329 degrees as the third logging curve, that is, the reef body indication factor curve; the angle corresponding to the third logging curve is the reef body indication factor angle, that is, take 329 degrees as the reef body indication factor angle.

[0081] S250. Construct a geological model and an attribute model of the target formation, perform forward modeling to generate a synthetic gather, and perform inversion on the synthetic gather to verify the reef body indication factor curve.

[0082] Wherein, after determining the reef body indication factor curve and the reef body indication factor angle, verify the reef body indication factor curve by establishing a theoretical model.

[0083] As an optional but non-limiting implementation manner, constructing the geological model and the attribute model of the target formation, performing forward modeling to generate a synthetic gather, and performing inversion on the synthetic gather to verify the reef body indication factor curve includes, but is not limited to, steps A1 - A5:

[0084] Step A1: Construct a geological model and an attribute model of the target formation according to the logging data and logging interpretation results of the target formation.

[0085] Step A2: Carry out forward modeling simulation using the wave equation algorithm, and generate a synthetic gather from the geological model and the attribute model.

[0086] Step A3: Apply prestack simultaneous inversion technology to perform inversion on the synthetic gather, generating a P-wave impedance data volume and an S-wave impedance data volume.

[0087] Step A4: Perform elastic impedance inversion on the P-wave impedance data volume and the S-wave impedance data volume to determine the reef body indicator factor data volume.

[0088] Step A5: Verify the reef body indicator factor curve based on the reef body indicator factor data volume.

[0089] Among them, referring to Figure 5 , based on the logging data and logging interpretation results of the target formation, establish an AVO forward geological model and an attribute model; among them, limestone is a kind of carbonate rock, and mudstone is a kind of clastic rock. Based on the logging data and logging interpretation results of limestone and mudstone, establish a geological model and an attribute model. Among them, the geological model sets the thickness and longitudinal distribution sequence of carbonate rock and clastic rock. The attribute model sets the P-wave velocity, S-wave velocity and density of carbonate rock and clastic rock. Use the wave equation algorithm to carry out AVO forward simulation to generate a synthetic gather; apply prestack simultaneous inversion technology to perform inversion on the synthetic gather to generate a P-wave impedance and an S-wave impedance data volume; obtain the reef body indicator factor data volume, and use a one-dimensional profile method to display and interpret the distribution characteristics of the reef body, that is, the larger the reef body indicator factor, the reef body, thus proving the possibility and reliability of predicting the reef body by this technical solution.

[0090] As an optional but non-limiting implementation method, the verification of the reef body indicator factor curve based on the reef body indicator factor data volume includes but is not limited to steps B1 - B2:

[0091] Step B1: Determine the inversion profile of the reef body indicator factor data volume and display the lithology distribution characteristics of the formation; among them, the lithology distribution characteristics of the reef body in the inversion profile are different from those of other formations.

[0092] Step B2: Verify the reef body indicator factor curve based on the lithology distribution characteristics of the formation.

[0093] Among them, to determine the inversion profile of the reef body indicator factor data volume and the lithology distribution characteristics of the formation, refer to Figure 6 , it can be seen that for the reef body indicator factor (R 329 O ) inversion profile corresponding to the carbonate rock formation shows dark red blocks, that is, high values of the reef body indicator factor; while the reef body indicator factors of other lithologies are medium - low values, showing green - blue; thus it can be seen that the reef body indicator factor inversion can accurately predict the reef body.

[0094] An embodiment of the present invention provides a method for constructing a reef body indication factor. Based on the logging data and logging interpretation results of carbonate strata, the logging response characteristics of carbonate rocks are determined, and the first logging curve for characterizing the sensitive curve of carbonate strata is determined; the longitudinal wave impedance and transverse wave impedance of the target formation are determined, and at least two second logging curves are determined based on elastic impedance inversion; the at least two second logging curves are respectively calculated for correlation with the first logging curve, and the second logging curve with the largest correlation calculation result is used as the reef body indication factor curve, and the corresponding angle is used as the reef body indication factor angle; the reef body indication factor curve is verified by establishing a theoretical model. By adopting the technical solution of the embodiment of the present invention, a reef body indication factor capable of accurately predicting the distribution characteristics of reef bodies is constructed, laying a good foundation for the analysis of marine strata sedimentary environment, paleogeomorphic restoration, and exploration and development of reef body oil and gas reservoirs in areas with low exploration degree.

[0095] Embodiment III

[0096] Figure 7 FIG. 7 is a flowchart of a reef body prediction method in an area without wells provided in an embodiment of the present invention. This embodiment is applicable to the case of predicting reef bodies in an area without wells based on the constructed reef body indication factor. The method of this embodiment can be executed by a reef body prediction device in an area without wells, and this device can be implemented in a hardware and / or software manner. This device can be configured in a server for reef body prediction in an area without wells. The method specifically includes the following steps:

[0097] S710. Obtain the common reflection point gather data of the formation in the area without wells, and analyze the common reflection point gather data to generate an attribute data volume.

[0098] Among them, in the formation in the area without wells lacking drilling data and logging data, obtain the common reflection point gather data of the formation in the area without wells, and analyze the common reflection point gather data to generate an attribute data volume. For example, perform AVO attribute analysis on the common reflection point gather data to generate a P attribute data volume and a P-G attribute data volume of AVO. Among them, the P attribute data volume refers to the data volume that is positively correlated with the longitudinal wave impedance, and the P-G attribute data volume refers to the data volume that is positively correlated with the transverse wave impedance.

[0099] S720. Analyze the attribute data volume to determine the longitudinal wave impedance data volume and the transverse wave impedance data volume.

[0100] Among them, by analyzing the P attribute data volume and the P-G attribute data volume, determine the longitudinal wave impedance data volume and the transverse wave impedance data volume.

[0101] As an optional but non-limiting implementation manner, the analyzing the attribute data volume to determine the longitudinal wave impedance data volume and the transverse wave impedance data volume includes, but is not limited to, steps C1-C3:

[0102] Step C1: Convert the attribute data volume into a P-wave velocity data volume and an S-wave velocity data volume, and determine the density data volume based on the P-wave velocity data volume.

[0103] Step C12: Perform low-pass filtering on the density data volume, the P-wave velocity data volume, and the S-wave velocity data volume to obtain the low-frequency initial models of the P-wave velocity, the S-wave velocity, and the density.

[0104] Step C3: Perform prestack inversion on the low-frequency initial models of the P-wave velocity, the S-wave velocity, and the density to generate a P-wave impedance data volume and an S-wave impedance data volume.

[0105] Among them, according to the relationship between the P attribute of the theoretical model and the P-wave velocity, and the relationship between the P-G attribute and the S-wave velocity, convert the AVO attribute data volume into a P-wave velocity data volume and an S-wave velocity data volume; and use the Gardner equation to obtain the density data volume. Perform low-pass filtering on the density data volume, the P-wave velocity data volume, and the S-wave velocity data volume to obtain the low-frequency initial models of the prestack inversion P-wave velocity, S-wave velocity, and density; generate a P-wave impedance data volume and an S-wave impedance data volume through prestack inversion.

[0106] S730: Determine the reef indicator factor data volume based on the P-wave impedance data volume, the S-wave impedance data volume, and the reef indicator factor angle.

[0107] Among them, after determining the P-wave impedance data volume and the S-wave impedance data volume, input the S-wave impedance and the P-wave impedance into the Connolly formula, and substitute the reef indicator factor angle to obtain the reef indicator factor data volume.

[0108] S740: Predict the reefs in the formation of the well-free area based on the reef indicator factor data volume.

[0109] Among them, identify the reefs and other lithologies based on the values of the reef indicator factor data volume. See Figure 8 , the color scale of the reef indicator factor data volume represents the high and low of the reef indicator factor. High values in red represent reefs, low values in blue represent mudstones, and intermediate values in yellow - blue-green represent sandstones. In the shale content curve, reefs are low values, mudstones are high values, and sandstones are medium - low values. The accuracy of the reef prediction by the reef indicator factor can be verified by the shale content curve.

[0110] An embodiment of the present invention provides a reef prediction method for a wellless area. By obtaining common reflection point gather data of the formation in the wellless area and analyzing the common reflection point gather data, an attribute data volume is generated; analyzing the attribute data volume to determine a longitudinal wave impedance data volume and a shear wave impedance data volume; determining a reef indication factor data volume based on the longitudinal wave impedance data volume, the shear wave impedance data volume, and the reef indication factor angle; and predicting the reef in the formation of the wellless area based on the reef indication factor data volume. By adopting the technical solution of the embodiment of the present invention, under the conditions of the formation in the wellless area and the lack of drilling data, that is, logging data, the reef indication factor data volume can be determined based on the gather data to predict the reef in the formation of the wellless area.

[0111] Embodiment 4

[0112] Figure 9 It is a schematic structural diagram of a reef indication factor construction device provided in an embodiment of the present invention. The technical solution of this embodiment is applicable to the situation of constructing a reef indication factor based on logging data. The device can be implemented by software and / or hardware and is generally integrated on any electronic device with network communication functions. The electronic device includes, but is not limited to: devices such as servers, computers, and personal digital assistants. As Figure 9 shown, the reef indication factor construction device provided in this embodiment may include: a logging data acquisition module 910, a reef indication factor construction module 920, and a reef indication factor verification module 930; wherein,

[0113] The logging data acquisition module 910 is configured to acquire logging data and logging interpretation results of a target formation; wherein, the target formation includes a carbonate formation and a clastic rock formation;

[0114] The reef indication factor construction module 920 is configured to construct a reef indication factor curve and determine a reef indication factor angle based on the logging data and logging interpretation results of the carbonate formation; wherein, the reef indication factor curve is used to characterize the existence of a reef, and the carbonate formation includes a reef;

[0115] The reef indication factor verification module 930 is configured to construct a geological model and an attribute model of the target formation and perform forward modeling to generate a synthetic gather, and perform inversion on the synthetic gather to verify the reef indication factor curve.

[0116] Based on the above embodiments, optionally, the reef indication factor construction module is specifically configured to:

[0117] Determine the logging response characteristics of the carbonate formation and determine a first logging curve based on the logging data and logging interpretation results of the carbonate formation; wherein, the first logging curve is used to characterize the sensitive curve of the carbonate formation;

[0118] Determine the longitudinal wave impedance and shear wave impedance of the target formation, and determine at least two second logging curves based on elastic impedance inversion; the second logging curves are obtained by elastic impedance inversion at different angles;

[0119] Perform correlation calculations on the at least two second logging curves with the first logging curve respectively to determine a third logging curve, and use the third logging curve as the reef body indication factor curve; wherein, the angle corresponding to the third logging curve is the reef body indication factor angle.

[0120] Based on the above embodiments, optionally, the reef body indication factor verification module is specifically configured to:

[0121] Construct a geological model and an attribute model of the target formation based on the logging data and logging interpretation results of the target formation;

[0122] Carry out forward modeling using the wave equation algorithm, and generate a synthetic gather from the geological model and the attribute model;

[0123] Apply prestack simultaneous inversion technology to invert the synthetic gather to generate a longitudinal wave impedance data volume and a shear wave impedance data volume;

[0124] Perform elastic impedance inversion on the longitudinal wave impedance data volume and the shear wave impedance data volume to determine the reef body indication factor data volume;

[0125] Verify the reef body indication factor curve based on the reef body indication factor data volume.

[0126] Based on the above embodiments, optionally, the reef body indication factor verification module is specifically configured to:

[0127] Determine the inversion profile of the reef body indication factor data volume and display the formation lithology distribution characteristics; wherein, the lithology distribution characteristics of the reef body in the inversion profile are different from those of other formations;

[0128] Verify the reef body indication factor curve based on the formation lithology distribution characteristics.

[0129] The reef body indication factor construction device provided in the embodiments of the present invention can execute the reef body indication factor construction method provided in any of the above embodiments of the present invention, and has the corresponding functions and beneficial effects for executing the reef body indication factor construction method. For the detailed process, refer to the relevant operations of the reef body indication factor construction method in the foregoing embodiments.

[0130] Embodiment Five

[0131] Figure 10It is a schematic structural diagram of a reef prediction device in the well-free area provided in an embodiment of the present invention. The technical solution of this embodiment is applicable to the situation of predicting reefs in the well-free area based on the constructed reef indication factors. This device can be implemented by software and / or hardware and is generally integrated on any electronic device with network communication functions, including but not limited to devices such as servers, computers, and personal digital assistants. As Figure 10 shown, the reef prediction device in the well-free area provided in this embodiment may include: a common reflection point gather data analysis module 1010, an impedance data volume determination module 1020, a reef indication factor data volume determination module 1030, and a well-free area reef prediction module 1040; among them,

[0132] The common reflection point gather data analysis module 1010 is used to obtain the common reflection point gather data of the formation in the well-free area and analyze the common reflection point gather data to generate an attribute data volume;

[0133] The impedance data volume determination module 1020 is used to analyze the attribute data volume to determine a P-wave impedance data volume and an S-wave impedance data volume;

[0134] The reef indication factor data volume determination module 1030 is used to determine a reef indication factor data volume according to the P-wave impedance data volume, the S-wave impedance data volume, and the reef indication factor angle;

[0135] The well-free area reef prediction module 1040 is used to predict the reefs in the formation of the well-free area according to the reef indication factor data volume.

[0136] On the basis of the above embodiment, optionally, the impedance data volume determination module is specifically used for:

[0137] Convert the attribute data volume into a P-wave velocity data volume and an S-wave velocity data volume, and determine a density data volume according to the P-wave velocity data volume;

[0138] Perform low-pass filtering on the density data volume, the P-wave velocity data volume, and the S-wave velocity data volume to obtain a low-frequency initial model of P-wave velocity, S-wave velocity, and density;

[0139] Perform prestack inversion on the low-frequency initial model of P-wave velocity, S-wave velocity, and density to generate a P-wave impedance data volume and an S-wave impedance data volume.

[0140] Among them, the reef indication factor angle is obtained by using any of the reef indication factor construction methods in the above embodiment. After entering the application stage, the reef indication factor data volume can be determined according to the reef indication factor angle to predict the reefs in the target formation.

[0141] The reef prediction device in the embodiment of the present invention can execute the reef prediction method in any embodiment of the present invention, and has the corresponding functions and beneficial effects for executing the reef prediction method. For the detailed process, refer to the related operations of the reef prediction method in the foregoing embodiments.

[0142] Embodiment Six

[0143] Figure 11 It is a schematic structural diagram of an electronic device provided in an embodiment of the present invention. The electronic device 10 is intended to represent various forms of digital computers, such as, laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as, personal digital processors, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are only examples and are not intended to limit the implementation of the present invention described and / or claimed herein.

[0144] As Figure 11 shown, the electronic device 10 includes at least one processor 11, and a memory communicatively connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc. Among them, the memory stores a computer program executable by the at least one processor. The processor 11 can execute various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 into the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. The input / output (I / O) interface 15 is also connected to the bus 14.

[0145] Multiple components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a magnetic disk, an optical disc, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0146] The processor 11 may be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as the reef body indication factor construction and reef body prediction method in the well-free area.

[0147] In some embodiments, the reef body indication factor construction and reef body prediction method in the well-free area may be implemented as a computer program tangibly embodied in a computer-readable storage medium, such as the storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed onto the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the reef body indication factor construction and reef body prediction method described above may be executed. Alternatively, in other embodiments, the processor 11 may be configured to execute the reef body indication factor construction and reef body prediction method in any other suitable manner (e.g., by means of firmware).

[0148] Various embodiments of the systems and techniques described above in this document may be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGA), application-specific integrated circuits (ASIC), application-specific standard products (ASSP), system-on-chip systems (SOC), complex programmable logic devices (CPLD), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include: implemented in one or more computer programs that may be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a special-purpose or general-purpose programmable processor that receives data and instructions from a storage system, at least one input device, and at least one output device, and transmits the data and instructions to the storage system, the at least one input device, and the at least one output device.

[0149] The computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when the computer programs are executed by the processor, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The computer programs may be executed entirely on the machine, partially on the machine, as a stand-alone software package partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0150] In the context of the present invention, a computer-readable storage medium can be a tangible medium that can contain or store a computer program for use by or in connection with an instruction execution system, apparatus, or device. The computer-readable storage medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. Alternatively, the computer-readable storage medium can be a machine-readable signal medium. More specific examples of the machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0151] To provide for interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or a trackball) by which the user can provide input to the electronic device. Other kinds of devices can also be used to provide for interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, speech input, or tactile input).

[0152] The systems and techniques described herein can be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer having a graphical user interface or a web browser through which the user can interact with an implementation of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0153] A computing system may include a client and a server. The client and the server are generally far from each other and usually interact via a communication network. The relationship between the client and the server is generated by computer programs running on corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or a cloud host, which is a host product in the cloud computing service system, solving the defects of difficult management and weak business scalability existing in traditional physical hosts and VPS services.

[0154] Embodiment VII

[0155] The embodiment of the present invention also provides a computer program product, including a computer program, which when executed by a processor, implements the reef body indication factor construction and reef body prediction method in a well-free area provided in any embodiment of the present application.

[0156] In the process of implementing the computer program product, computer program code for performing the operations of the present invention can be written in one or more programming languages or combinations thereof. The programming languages include object-oriented programming languages such as Java, Smalltalk, C++, and also include conventional procedural programming languages such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, executed as an independent software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer can be connected to the user's computer through any type of network - including a local area network (LAN) or a wide area network (WAN) - or can be connected to an external computer (for example, by using an Internet service provider to connect through the Internet).

[0157] It should be understood that various forms of the processes shown above can be used, with steps reordered, added, or deleted. For example, the steps recited in the present invention can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved, and no limitation is made herein.

[0158] The above specific embodiments do not constitute a limitation to the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for constructing a reef indicator factor, characterized in that: The reef indicator factor construction method comprises: Acquire well logging data and well logging interpretation results of target formations; wherein the target formations include carbonate formations and clastic formations; Based on the logging data and logging interpretation results of the carbonate formation, a reef indicator factor curve is constructed and a reef indicator factor angle is determined; wherein the reef indicator factor curve is used to characterize the existence of the reef, and the carbonate formation includes the reef; The geological model and attribute model of the target stratum are constructed and forward modeling is performed to generate synthetic gathers, which are then inverted to verify the reef indicator factor curve.

2. The method according to claim 1, characterized in that The method of constructing a reef indicator factor curve and determining a reef indicator factor angle based on the well logging data and well logging interpretation results of the carbonate formation includes: According to the logging data of the carbonate formation and the logging interpretation results, the carbonate logging response characteristics are determined and a first logging curve is determined; wherein the first logging curve is used to characterize the sensitivity curve of the carbonate formation; Determine the longitudinal wave impedance and the shear wave impedance of the target formation, and determine at least two second logging curves based on elastic impedance inversion; the second logging curves are obtained by elastic impedance inversion at different angles; The at least two second logging curves are respectively correlated with the first logging curve to determine a third logging curve, and the third logging curve is used as a reef indication factor curve; wherein the angle corresponding to the third logging curve is the reef indication factor angle.

3. The method according to claim 1, characterized in that The method of constructing a geological model and an attribute model of the target stratum to perform forward modeling of synthetic gathers, and inverting the synthetic gathers to verify the reef indicator factor curve includes: Construct the geological model and attribute model of the target formation based on the logging data and logging interpretation results of the target formation; The wave equation algorithm is used to carry out forward simulation and generate synthetic gathers from geological models and attribute models; Applying prestack synchronous inversion technology to invert the synthetic gathers to generate a P-wave impedance data volume and a S-wave impedance data volume; Performing elastic impedance inversion on the longitudinal wave impedance data volume and the transverse wave impedance data volume to determine the reef indicator factor data volume; The reef indicator factor curve is verified based on the reef indicator factor data body.

4. The method according to claim 3, characterized in that: The verifying the reef indicator factor curve according to the reef indicator factor data body includes: Determine the inversion profile of the reef indicator factor data body and display the lithology distribution characteristics of the strata; wherein the lithology distribution characteristics of the reef in the inversion profile are different from those of other strata; According to the lithology distribution characteristics of the formation, the reef indicator factor curve is verified.

5. A method for predicting reef bodies in well-free areas, characterized in that: The reef indicator factor angle determined by the reef indicator factor construction method described in any one of claims 1 to 4, the method for predicting reefs in well-free areas comprises: Acquire common reflection point gather data of the formation in the well-free area, and analyze the common reflection point gather data to generate an attribute data body; Analyzing the attribute data volume to determine a longitudinal wave impedance data volume and a transverse wave impedance data volume; Determining a reef indicator factor data volume according to the longitudinal wave impedance data volume, the transverse wave impedance data volume and the reef indicator factor angle; The reef bodies in the well-free formation are predicted based on the reef body indicator factor data body.

6. The method according to claim 5, characterized in that The analyzing the attribute data body to determine the longitudinal wave impedance data body and the transverse wave impedance data body includes: The attribute data volume is converted into a longitudinal wave velocity data volume and a transverse wave velocity data volume, and the density data volume is determined according to the longitudinal wave velocity data volume; The density data volume, the longitudinal wave velocity data volume and the shear wave velocity data volume are low-pass filtered to obtain the initial low-frequency models of the longitudinal wave velocity, the shear wave velocity and the density; The P-wave velocity, S-wave velocity and density low-frequency initial model are pre-stack inverted to generate P-wave impedance data volume and S-wave impedance data volume.

7. A reef indicator factor construction device, characterized in that: The device comprises: A logging data acquisition module is used to acquire logging data and logging interpretation results of target formations; wherein the target formations include carbonate formations and clastic formations; A reef indicator factor construction module is used to construct a reef indicator factor curve and determine a reef indicator factor angle based on well logging data and well logging interpretation results of carbonate formations; wherein the reef indicator factor curve is used to characterize the existence of reefs, and carbonate formations include reefs; The reef indicator factor verification module is used to construct the geological model and attribute model of the target stratum and generate synthetic gathers by forward modeling, and invert the synthetic gathers to verify the reef indicator factor curve.

8. A reef prediction device for well-free areas, characterized in that: The device comprises: A gather data analysis module is used to obtain common reflection point gather data of the formation in the well-free area, and analyze the common reflection point gather data to generate an attribute data body; An impedance data volume determination module is used to analyze the attribute data volume to determine a longitudinal wave impedance data volume and a transverse wave impedance data volume; A reef indicator factor data volume determination module is used to determine the reef indicator factor data volume based on the longitudinal wave impedance data volume, the transverse wave impedance data volume and the reef indicator factor angle; The module for predicting reef bodies in well-free areas is used to predict reef bodies in well-free areas according to the reef body indicator factor data body.

9. An electronic device, characterized in that: include: one or more processors; A storage device for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the reef indicator factor construction method described in any one of claims 1-4 and the well-free area reef prediction method described in any one of claims 5-6.

10. A storage medium containing computer executable instructions, characterized in that: The computer executable instructions are used to execute the reef indicator factor construction method described in any one of claims 1 to 4 and the well-free area reef prediction method described in any one of claims 5 to 6 when executed by a computer processor.

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