Lithology constraint-based logging curve standardization method and device, electronic equipment and medium

Abstract

The invention discloses a logging curve standardization method and device based on lithologic constraint, electronic equipment and a medium. The method comprises the following steps: constructing lithology constraint factors; according to the lithologic constraint factors, reconstructing a logging curve; according to the reconstructed logging curve of the standard well and the correction well, the single well correction value is calculated; and performing logging curve standardization according to the single well correction value. Lithology constraints are introduced in the well logging curve standardization process, a standard layer is replaced by improving the weight of a target layer section and the weight of a nearby mudstone microlayer, and the high-precision single well correction value is effectively calculated.

Description

Technical Field

[0001] The present invention relates to the field of geophysical prospecting applications, and more particularly to a method, device, electronic equipment and medium for standardizing well logging curves based on lithologic constraints. Background Art

[0002] Well logging curves are primarily used for petrophysical analysis, AVO analysis, and post-stack and pre-stack inversion, and are essential data for reservoir prediction. However, the acquisition of well logging data often results in systematic and random errors in well logging curves between wells (and adjacent wells) with similar sedimentary backgrounds within the study area due to non-geological factors such as environmental factors, instrumental factors, and human factors. This leads to poor inter-well consistency and hinders reservoir prediction. Well logging curve standardization aims to eliminate inter-well (and adjacent well) errors caused by non-geological factors and improve inter-well consistency.

[0003] Generally, well log normalization assumes the presence of a set of lithologically stable reference layers within the study area, often consisting of large mudstone intervals. This is due to the relative stability of mudstone within the same sedimentary setting. By comparing the frequency domain histograms of the well logs from a single well with those from a reference well near the reference layer, the correction for the single well is calculated and normalized. However, it is often difficult to find a set of lithologically stable reference layers within or near the target interval. Furthermore, the reference layer and the target interval may not coincide with the same logging run, making high-precision well log normalization difficult.

[0004] At present, a method for normalizing well logging curves based on lithologic constraints needs to be developed.

[0005] The information disclosed in the background technology section of the present invention is only intended to deepen the understanding of the general background technology of the present invention, and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. Summary of the Invention

[0006] The present invention proposes a logging curve standardization method, device, electronic equipment and medium based on lithologic constraints, which can introduce lithologic constraints during the logging curve standardization process, and effectively calculate high-precision single-well correction values ​​by increasing the weight of the target layer and nearby mudstone microlayers to replace the standard layer.

[0007] In a first aspect, an embodiment of the present disclosure provides a method for normalizing well logging curves based on lithologic constraints, comprising:

[0008] Construct lithologic constraint factors;

[0009] reconstructing a well logging curve according to the lithologic constraint factor;

[0010] Calculate the single well correction amount based on the reconstructed logging curves of the standard well and the correction well;

[0011] The logging curve is normalized according to the single well correction value.

[0012] Preferably, the lithology constraint factor is constructed by dividing the lithology curve into percentages.

[0013] Preferably, the lithologic constraint factor is:

[0014]

[0015] Among them, GR percentage is the lithologic constraint factor, GR is the natural gamma, GR max GR min are the maximum and minimum values ​​of GR.

[0016] Preferably, the reconstructed logging curve is:

[0017] Pimp rebuild =Pimp*GR percentage

[0018] Among them, Pimp rebuild is the reconstructed logging curve, GR percentage is the lithologic constraint factor, and Pimp is the well logging curve.

[0019] Preferably, calculating the single well correction amount based on the reconstructed logging curves of the standard well and the correction well includes:

[0020] The reconstructed logging curve is subjected to frequency histogram statistics in the target layer, compared with the reconstructed logging curve of the standard well, and the single well correction amount is calculated.

[0021] Preferably, the single well correction amount is:

[0022] Pimp correction =Pimp rebuild (Correction Well)-Pimp rebuild (Standard Well)

[0023] Among them, Pimp correction is the single well correction value.

[0024] Preferably, the well logging curve is normalized as follows:

[0025] Pimp (after correction) = Pimp (before correction) - Pimp correction

[0026] Among them, Pimp correction is the single well correction value.

[0027] In a second aspect, the embodiments of the present disclosure further provide a well logging curve normalization device based on lithologic constraints, comprising:

[0028] Building modules and constructing lithologic constraint factors;

[0029] A reconstruction module, for reconstructing the well logging curve according to the lithologic constraint factors;

[0030] The calculation module calculates the single well correction amount based on the reconstructed logging curves of the standard well and the correction well;

[0031] A standardization module is used to standardize the logging curve according to the single well correction value.

[0032] Preferably, the lithology constraint factor is constructed by dividing the lithology curve into percentages.

[0033] Preferably, the lithologic constraint factor is:

[0034]

[0035] Among them, GR percentage is the lithologic constraint factor, GR is the natural gamma, GR max GR min are the maximum and minimum values ​​of GR.

[0036] Preferably, the reconstructed logging curve is:

[0037] Pimp rebuild =Pimp*GR percentage

[0038] Among them, Pimp rebuild is the reconstructed logging curve, GR percentage is the lithologic constraint factor, and Pimp is the well logging curve.

[0039] Preferably, calculating the single well correction amount based on the reconstructed logging curves of the standard well and the correction well includes:

[0040] The reconstructed logging curve is subjected to frequency histogram statistics in the target layer, compared with the reconstructed logging curve of the standard well, and the single well correction amount is calculated.

[0041] Preferably, the single well correction amount is:

[0042] Pimp correction =Pimp rebuild (Correction Well)-Pimp rebuild (Standard Well)

[0043] Among them, Pimp correction is the single well correction value.

[0044] Preferably, the well logging curve is normalized as follows:

[0045] Pimp (after correction) = Pimp (before correction) - Pimp correction

[0046] Among them, Pimp correction is the single well correction value.

[0047] In a third aspect, an embodiment of the present disclosure further provides an electronic device, the electronic device comprising:

[0048] a memory storing executable instructions;

[0049] A processor runs the executable instructions in the memory to implement the well logging curve normalization method based on lithologic constraints.

[0050] In a fourth aspect, an embodiment of the present disclosure further provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the well logging curve normalization method based on lithologic constraints.

[0051] The methods and apparatus of the present invention have other features and advantages that will be apparent from or will be described in detail in the accompanying drawings and subsequent detailed descriptions incorporated herein, which together serve to explain the specific principles of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present invention.

[0053] Figure 1 A flowchart showing the steps of a well logging curve normalization method based on lithologic constraints according to an embodiment of the present invention is shown.

[0054] Figure 2 A schematic diagram showing the construction of lithologic constraint factors according to an embodiment of the present invention is shown.

[0055] Figure 3 FIG. 4 is a schematic diagram showing well logging curve reconstruction according to an embodiment of the present invention.

[0056] Figure 4 A schematic diagram of calculating the correction amount for a single well according to an embodiment of the present invention is shown.

[0057] Figure 5A schematic diagram illustrating normalization of well logging curves according to an embodiment of the present invention is shown.

[0058] Figure 6 A block diagram of a well logging curve normalization device based on lithologic constraints according to an embodiment of the present invention is shown.

[0059] Description of reference numerals:

[0060] 201. Construction module; 202. Reconstruction module; 203. Calculation module; 204. Standardization module. DETAILED DESCRIPTION

[0061] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0062] To facilitate understanding of the solutions and effects of the embodiments of the present invention, six specific application examples are given below. Those skilled in the art should understand that these examples are only for facilitating understanding of the present invention, and any specific details thereof are not intended to limit the present invention in any way.

[0063] Example 1

[0064] Figure 1 A flowchart showing the steps of a well logging curve normalization method based on lithologic constraints according to an embodiment of the present invention is shown.

[0065] like Figure 1 As shown, the logging curve standardization method based on lithologic constraint includes: step 101, constructing a lithologic constraint factor; step 102, reconstructing the logging curve according to the lithologic constraint factor; step 103, calculating the single-well correction value according to the reconstructed logging curves of the standard well and the correction well; step 104, standardizing the logging curve according to the single-well correction value.

[0066] In one example, the lithology constraint factor is constructed by percentage-based lithology curves.

[0067] In one example, the lithologic constraint factor is:

[0068]

[0069] Among them, GR percentage is the lithologic constraint factor, GR is the natural gamma, GR max GR min are the maximum and minimum values ​​of GR.

[0070] In one example, the reconstructed well log is:

[0071] Pimprebuild =Pimp*GR percentage

[0072] Among them, Pimp rebuild is the reconstructed logging curve, GR percentage is the lithologic constraint factor, and Pimp is the well logging curve.

[0073] In one example, calculating the single well correction amount based on the reconstructed logging curves of the standard well and the correction well includes:

[0074] The reconstructed logging curve is statistically analyzed by frequency histogram in the target layer, compared with the reconstructed logging curve of the standard well, and the correction amount of the single well is calculated.

[0075] In one example, the single-well correction is:

[0076] Pimp correction =Pimp rebuild (Correction Well)-Pimp rebuild (Standard Well)

[0077] Among them, Pimp correction is the single well correction value.

[0078] In one example, the well logs are normalized to:

[0079] Pimp (after correction) = Pimp (before correction) - Pimp correction

[0080] Among them, Pimp correction is the single well correction value.

[0081] Specifically, ① Construction of lithologic constraint factors: Percentage-based lithologic curves (GR or SH) are used to construct lithologic constraint factors:

[0082]

[0083] ② Logging curve reconstruction (taking the Pimp curve as an example): Multiply the logging curve with the lithologic constraint factor to reconstruct the logging curve:

[0084] Pimp rebuild =Pimp*GR percentage

[0085] ③ Calculation of single well correction (taking the Pimp curve as an example): Perform frequency histogram statistics on the reconstructed logging curve in and around the target layer, and compare it with the standard well to calculate the single well correction:

[0086] Pimp correction =Pimp rebuild (Correction Well)-Pimp rebuild (Standard Well)

[0087] ④ Logging curve standardization (taking Pimp curve as an example): Use the single well correction value to perform logging curve standardization:

[0088] Pimp (after correction) = Pimp (before correction) - Pimp correction .

[0089] Example 2

[0090] The present invention also provides a well logging curve standardization device based on lithologic constraints, comprising:

[0091] Building modules and constructing lithologic constraint factors;

[0092] Reconstruction module, reconstructs the logging curve according to the lithologic constraint factors;

[0093] The calculation module calculates the single well correction amount based on the reconstructed logging curves of the standard well and the correction well;

[0094] The standardization module standardizes the logging curve according to the single well correction value.

[0095] In one example, the lithology constraint factor is constructed by percentage-based lithology curves.

[0096] In one example, the lithologic constraint factor is:

[0097]

[0098] Among them, GR percentage is the lithologic constraint factor, GR is the natural gamma, GR max GR min are the maximum and minimum values ​​of GR.

[0099] In one example, the reconstructed well log is:

[0100] Pimp rebuild =Pimp*GR percentage

[0101] Among them, Pimp rebuild is the reconstructed logging curve, GR percentage is the lithologic constraint factor, and Pimp is the well logging curve.

[0102] In one example, calculating the single well correction amount based on the reconstructed logging curves of the standard well and the correction well includes:

[0103] The reconstructed logging curve is statistically analyzed by frequency histogram in the target layer, compared with the reconstructed logging curve of the standard well, and the correction amount of the single well is calculated.

[0104] In one example, the single-well correction is:

[0105] Pimp correction =Pimp rebuild (Correction Well)-Pimp rebuild (Standard Well)

[0106] Among them, Pimp correction is the single well correction value.

[0107] In one example, the well logs are normalized to:

[0108] Pimp (after correction) = Pimp (before correction) - Pimp correction

[0109] Among them, Pimp correction is the single well correction value.

[0110] Specifically, ① Construction of lithologic constraint factors: Percentage-based lithologic curves (GR or SH) are used to construct lithologic constraint factors:

[0111]

[0112] ② Logging curve reconstruction (taking the Pimp curve as an example): Multiply the logging curve with the lithologic constraint factor to reconstruct the logging curve:

[0113] Pimp rebuild =Pimp*GR percentage

[0114] ③ Calculation of single well correction (taking the Pimp curve as an example): Perform frequency histogram statistics on the reconstructed logging curve in and around the target layer, and compare it with the standard well to calculate the single well correction:

[0115] Pimp correction =Pimp rebuild (Correction Well)-Pimp rebuild (Standard Well)

[0116] ④ Logging curve standardization (taking Pimp curve as an example): Use the single well correction value to perform logging curve standardization:

[0117] Pimp (after correction) = Pimp (before correction) - Pimp correction .

[0118] Example 3

[0119] A certain basin is one of the most resource-rich geological units in China for coalbed methane resources. A particular gas field has been a key target for deep coalbed methane exploration and development in recent years. In particular, the Yangmei 1 well gas test, which produced over 100,000 cubic meters of gas per day, reveals the region's enormous potential for deep coalbed methane. However, geological factors crucial to the delineation of favorable areas, such as coal reservoir thickness prediction, coal seam roof structural depth and morphology, coal seam roof sealing, and reservoir fracture development, remain unclear. Prediction accuracy has not yet met required standards, and the accuracy of drilling engineering evaluations, such as the coal seam pressure coefficient and brittleness index, urgently needs to be improved.

[0120] The exploration area of ​​the block is about 2000km 2 Exploration and development efforts primarily focus on tight sandstone reservoirs of the Upper Paleozoic and carbonate karst reservoirs of the Lower Paleozoic. Drilling data is relatively abundant, and understanding is relatively clear. However, exploration research on a certain coalbed methane formation is relatively limited, and further research is needed. The target stratum in this study area is the 8# coal seam of a certain formation, which is a swamp-tidal flat deposit with a thickness of approximately 8 to 13 meters. Seismic reflections show strong phases, good lateral continuity, and a wide distribution. However, the 8# coal seam exhibits rapid spatial variations in thickness, making accurate thickness prediction and definition of top and bottom boundaries challenging. Furthermore, bright coal, a high-quality reservoir, is relatively thin and exhibits complex relationships with semi-bright coal, dark coal, semi-dark coal, and interbedded gangue. To improve coal seam thickness prediction and define top and bottom boundaries, there is an urgent need to enhance the accuracy of well logging curve standardization and construct high-precision low-frequency models for quantitative coal seam inversion.

[0121] Figure 2 A schematic diagram showing the construction of lithologic constraint factors according to an embodiment of the present invention is shown.

[0122] Figure 3 FIG. 4 is a schematic diagram showing well logging curve reconstruction according to an embodiment of the present invention.

[0123] Figure 4 A schematic diagram of calculating the correction amount for a single well according to an embodiment of the present invention is shown.

[0124] Figure 5 A schematic diagram illustrating normalization of well logging curves according to an embodiment of the present invention is shown.

[0125] Therefore, in the implementation of this method, the GR curve is first used to construct the lithologic constraint factor, such as Figure 2 As shown in the figure, the impedance curve is then reconstructed using the lithology constraint factor, as shown in the figure. Figure 3 As shown in the figure, the weight of the target interval and the nearby mudstone microlayers is increased. Then, the reconstructed impedance curve is used to compare with the standard well in the frequency domain histogram of the logging curve to calculate the single well impedance correction value, as shown in the figure. Figure 4As shown, the single well impedance correction value is finally introduced into the impedance curve to be corrected to complete the single well impedance curve standardization process, as shown in Figure 5 Practical applications show that the well logging curve standardization method based on the present invention has high accuracy and good effect.

[0126] Example 4

[0127] Figure 6 A block diagram of a well logging curve normalization device based on lithologic constraints according to an embodiment of the present invention is shown.

[0128] like Figure 6 As shown, the well logging curve standardization device based on lithologic constraints includes:

[0129] Building module 201, building lithologic constraint factors;

[0130] Reconstruction module 202, reconstructs the well logging curve according to the lithologic constraint factor;

[0131] The calculation module 203 calculates the single well correction amount based on the reconstructed logging curves of the standard well and the correction well;

[0132] The standardization module 204 performs well logging curve standardization based on the single well correction value.

[0133] In one example, the lithology constraint factor is constructed by percentage-based lithology curves.

[0134] In one example, the lithologic constraint factor is:

[0135]

[0136] Among them, GR percentage is the lithologic constraint factor, GR is the natural gamma, GR max GR min are the maximum and minimum values ​​of GR.

[0137] In one example, the reconstructed well log is:

[0138] Pimp rebuild =Pimp*GR percentage

[0139] Among them, Pimp rebuild is the reconstructed logging curve, GR percentage is the lithologic constraint factor, and Pimp is the well logging curve.

[0140] In one example, calculating the single well correction amount based on the reconstructed logging curves of the standard well and the correction well includes:

[0141] The reconstructed logging curve is statistically analyzed by frequency histogram in the target layer, compared with the reconstructed logging curve of the standard well, and the correction amount of the single well is calculated.

[0142] In one example, the single-well correction is:

[0143] Pimp correction =Pimp rebuild (Correction Well)-Pimp rebuild (Standard Well)

[0144] Among them, Pimp correction is the single well correction value.

[0145] In one example, the well logs are normalized to:

[0146] Pimp (after correction) = Pimp (before correction) - Pimp correction

[0147] Among them, Pimp correction is the single well correction value.

[0148] Example 5

[0149] This embodiment provides an electronic device, which includes: a memory storing executable instructions; and a processor running the executable instructions in the memory to implement the above-mentioned well logging curve normalization method based on lithologic constraints.

[0150] An electronic device according to an embodiment of the present disclosure includes a memory and a processor.

[0151] The memory is used to store non-transitory computer-readable instructions. Specifically, the memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), a hard disk, flash memory, etc.

[0152] The processor may be a central processing unit (CPU) or other form of processing unit having data processing capability and / or instruction execution capability, and may control other components in the electronic device to perform desired functions. In one embodiment of the present disclosure, the processor is used to execute the computer-readable instructions stored in the memory.

[0153] Those skilled in the art should understand that in order to solve the technical problem of how to obtain a good user experience, this embodiment may also include well-known structures such as a communication bus and an interface, and these well-known structures should also be included in the scope of protection of this disclosure.

[0154] For detailed description of this embodiment, please refer to the corresponding description in the aforementioned embodiments, which will not be repeated here.

[0155] Example 6

[0156] This embodiment provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the method for normalizing well logging curves based on lithologic constraints is implemented.

[0157] According to an embodiment of the present disclosure, a computer-readable storage medium stores non-transitory computer-readable instructions, which, when executed by a processor, execute all or part of the steps of the aforementioned methods of the embodiments of the present disclosure.

[0158] The above-mentioned computer-readable storage media include, but are not limited to, optical storage media (e.g., CD-ROMs and DVDs), magneto-optical storage media (e.g., MOs), magnetic storage media (e.g., magnetic tapes or mobile hard disks), media with built-in rewritable non-volatile memory (e.g., memory cards), and media with built-in ROM (e.g., ROM cartridges).

[0159] Those skilled in the art should understand that the above description of the embodiments of the present invention is only for the purpose of illustrative purposes only to illustrate the beneficial effects of the embodiments of the present invention, and is not intended to limit the embodiments of the present invention to any given examples.

[0160] While various embodiments of the present invention have been described above, the above description is intended to be illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A method for normalizing well logging curves based on lithologic constraints, characterized in that: include: Construct lithologic constraint factors; reconstructing a well logging curve according to the lithologic constraint factor; Calculate the single well correction amount based on the reconstructed logging curves of the standard well and the correction well; The logging curve is normalized according to the single well correction value.

2. The method for normalizing well logging curves based on lithologic constraints according to claim 1, wherein: The lithology constraint factor is constructed by dividing the lithology curve into percentages.

3. The method for normalizing well logging curves based on lithologic constraints according to claim 2, wherein: The lithologic constraint factor is: Among them, GR percentage is the lithologic constraint factor, GR is the natural gamma, GR max GR min are the maximum and minimum values ​​of GR.

4. The method for normalizing well logging curves based on lithologic constraints according to claim 1, wherein: The reconstructed logging curve is: Pimp rebuild =Pimp*GR percentage Among them, Pimp rebuild is the reconstructed logging curve, GR percentage is the lithologic constraint factor, and Pimp is the well logging curve.

5. The method for normalizing well logging curves based on lithologic constraints according to claim 1, wherein: Based on the reconstructed logging curves of the standard well and the calibration well, the single well calibration amount is calculated including: The reconstructed logging curve is subjected to frequency histogram statistics in the target layer, compared with the reconstructed logging curve of the standard well, and the single well correction amount is calculated.

6. The method for normalizing well logging curves based on lithologic constraints according to claim 5, wherein: The single well correction amount is: Pimp correction =Pimp rebuild (Correction Well)-Pimp rebuild (Standard Well) Among them, Pimp correction is the single well correction value.

7. The method for normalizing well logging curves based on lithologic constraints according to claim 1, wherein: The well logging curve is normalized to: Pimp (after correction) = Pimp (before correction) - Pimp correction Among them, Pimp correction is the single well correction value.

8. A logging curve standardization device based on lithologic constraints, characterized in that: include: Building modules and constructing lithologic constraint factors; A reconstruction module, for reconstructing the well logging curve according to the lithologic constraint factors; The calculation module calculates the single well correction amount based on the reconstructed logging curves of the standard well and the correction well; A standardization module is used to standardize the logging curve according to the single well correction value.

9. An electronic device, characterized in that: The electronic device comprises: a memory storing executable instructions; A processor, wherein the processor runs the executable instructions in the memory to implement the well logging curve normalization method based on lithologic constraints according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method for normalizing well logging curves based on lithologic constraints according to any one of claims 1 to 7 is implemented.

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