CN116595396A - A logging curve standardization method and device based on multi-window anchor points - Google Patents

Abstract

The invention discloses a logging curve standardization method and device based on multi-window anchor points. For the traditional curve standardization method, the logging curve standardization method based on multi-window anchor points used in the present invention can provide a set of logging curves suitable for multiple trips The process of automatic depth matching of curves This process mainly includes logging data import, curve preprocessing, initial migration processing, logging curve attribute extraction, refined migration processing, generation of depth migration charts, application to multiple sets, and finally Well logging data is used for stratigraphic analysis and reservoir oil and gas evaluation. The standardization of well logging curves is to eliminate the systematic errors generated during the process of well logging data acquisition. Through curve standardization and correction, the well logging curve data corresponding to each well target layer have the same average value or similar frequency distribution, which provides a good foundation for subsequent reservoir evaluation and reservoir geology. The necessary basic work in the research.

Description

A logging curve standardization method and device based on multi-window anchor points

technical field

The invention relates to the technical field of petroleum and natural gas exploration and development, in particular to a logging curve standardization method and device based on multi-window anchor points.

Background technique

In the field of oil and gas exploration, well logging is widely used in oil and gas exploration, development, and well completion stages. Log interpretation plays an important role in formation evaluation and reservoir fluid property identification. The standardization of well logging curves refers to matching the depth of multiple well logging data of the same well, which provides a guarantee for providing complete interpretation conclusions, and can also ensure accurate operations of subsequent perforating, sidewall coring, and formation testing.

The standardization of logging curves usually uses natural gamma ray curves for depth matching, and other curves in the same set are depth-migrated according to the correction amount of natural gamma ray. There are two commonly used depth matching methods. One is an algorithm based on cross-correlation and variance, which cannot provide accurate depth matching and requires additional manual adjustments, so it cannot meet the requirements of automatic data processing. The second is deep matching based on machine learning. Machine learning can make up for the shortcomings of manual assistance. The training set of machine learning contains a large amount of oilfield data. In order to obtain a perfect model, the grid model needs to be continuously updated. The matching points are adjusted and the database is updated. The disadvantage of this method is that it is highly dependent on self-renewal and human-computer interaction in the early stage, and requires a large amount of training data to provide support. Therefore, an algorithm based on automatic processing is still needed to perform curve depth matching on multiple logging curves.

Contents of the invention

The purpose of the present invention is to overcome the above-mentioned deficiencies in the prior art, and provide a logging curve standardization method and device based on multi-window anchor points.

For realizing the above object, technical scheme of the present invention is:

In the first aspect, the present invention provides a method for standardizing well logging curves based on multi-window anchor points, comprising the steps of:

101. Import well logging data, the well logging data includes a well logging curve in the first trip of well logging data and a well logging curve in the second trip of well logging data, and the two well logging curves are the same type of well logging curves ;

102. Carry out curve preprocessing on the two imported well logging curves, so that the sampling rates of the two well logging curves are consistent, and obtain the two preprocessed well logging curves;

103. Perform initial offset processing on the two preprocessed logging curves;

104. Perform attribute extraction on the two logging curves after the initial migration, select a logging curve in the first logging data as the reference curve, and select a logging curve of the same type in the second logging data as the target Curve, identify one or more curve attributes by comparing the reference curve and the target curve, and obtain the anchor point pair of the two logging curves;

105. In the case of obtaining the anchor point pairs of the two logging curves, choose to execute the depth migration corresponding to the anchor point of the reference curve or the target curve, generate the final anchor point pair, and generate a depth migration chart;

106. Apply the generated depth migration chart to other curves in the second well logging data, so as to realize the standardization operation of all the well logging curves of the second well logging data.

Further, the described logging curve standardization method based on multi-window anchor points also includes the following steps:

107. After all logging curves are standardized, perform data analysis and reservoir oil and gas evaluation.

Further, in step 102, the curve preprocessing includes: 1) data resampling, changing the sampling rate of the data to a set interval; 2) suppressing the interference part of the two passes of data.

Further, in step 104, the attribute extraction adopts method, assuming that the logging curve in the first logging data is /> , the logging curve in the second logging data is /> , /> The calculation formula is: /> Where: /> is the depth, /> yes /> on average, /> yes /> on average, /> is about /> function, /> is about /> The function;

along the reference curve Direction sliding window, extracting a sequence of /> sample, get the corresponding /> data, forming a series of anchor pairs.

Further, in step 103, the initial offset processing of the preprocessed curve includes: 1) calculating the correlation coefficients of two well logging curves belonging to the first and second well logging data respectively, Then perform initial offset processing with a fixed value; 2) smooth the two log curves.

Further, the step 104 also includes: using windows of different sizes to find a suitable pair of anchor points to obtain an optimal solution; if the pair of anchor points under any selected window cannot match, it is considered as an invalid pair of anchor points.

In a second aspect, the present invention provides a logging curve standardization device based on multi-window anchor points, including a memory, a processor, and a computer program stored in the memory and operable on the processor, the processor The steps of any one of the above methods are realized when the computer program is executed.

In a third aspect, the present invention provides a computer-readable storage medium, where a computer program is stored in the computer-readable storage medium, and when the computer program is executed by a processor, the steps of any one of the methods described above are implemented.

Compared with the prior art, the present invention has the beneficial effects of:

For traditional curve standardization methods, the logging curve standardization method based on multi-window anchor points used in the present invention can provide a set of procedures suitable for automatic curve standardization of multiple logging curves, which mainly includes logging data import, curve prediction Processing, initial migration processing, log curve attribute extraction, refined migration processing, generation of depth migration charts, application to multiple sets, and finally stratigraphic analysis and reservoir oil and gas evaluation on logging data. The standardization of well logging curves is to eliminate the systematic errors generated during the process of well logging data acquisition. Through curve standardization and correction, the well logging curve data corresponding to each well target layer have the same average value or similar frequency distribution, which provides a good foundation for subsequent reservoir evaluation and reservoir geology. The necessary basic work in the research.

Description of drawings

Fig. 1 is the flow chart of the logging curve standardization method based on the multi-window anchor point provided by Embodiment 1 of the present invention;

FIG. 2 is a schematic diagram of attribute extraction in step 104 provided by Embodiment 1 of the present invention;

Fig. 3 is a schematic diagram of comparison before and after curve standardization in Example 1 of the present invention;

Fig. 4 is a schematic composition diagram of the logging curve standardization device based on multi-window anchor points provided by Embodiment 2 of the present invention.

Detailed ways

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Example 1:

This embodiment provides a logging curve standardization method based on multi-window anchor points, which can use a logging curve in the first logging data to perform curve standardization on the same measurement item in the second logging data. By calculating the offset distance of the correlation coefficient between the two well logging curves as the constant offset of the second well logging curve, automatic depth matching is finally realized. This process can also perform multi-feature picking of well logging curves, and then obtain specific depth migration charts through eigenvalue analysis, and apply the depth migration charts to the second curve to stretch or compress the curve. After applying the depth offset chart, all curves in this survey will be depth offset by the same, and applied to the entire data set. Finally, the standardized logging curves can be used for stratigraphic correlation, sedimentary evolution, fault analysis, etc., and can also be applied in engineering, such as determining perforation depth, coring layers, and formation testing layers.

Specifically, the logging curve standardization method based on multi-window anchor points mainly includes the following steps:

101. Import logging data

The imported logging data includes a logging curve and a logging curve and a depth coordinate system in the second logging data. The two logging curves are the same type of logging curves; select the natural gamma curve of the two logging data Other types of curves can also be imported as reference curves, such as acoustic time difference, bulk density, compensated neutron, etc.

102. Curve preprocessing

The purpose of curve preprocessing is to make the two data sampling rates consistent and remove outliers. Preprocessing the two imported well logging curves, including: 1) data resampling, changing the sampling rate of the data to a set interval, such as 1 foot or 2 feet; 2) suppressing the interference part of the two trip data, such as Outliers on the natural gamma curve, outliers can be zeroed or replaced by constant terms.

103. Initial offset processing

Perform initial offset processing on the two preprocessed curves: including performing 1) conventional preprocessing between the two curves, that is, calculating the values of the two logging curves belonging to the first and second logging data Correlation coefficient, and then perform initial offset processing with a fixed value. The correlation coefficient can be selected for a certain curve, and the maximum offset can be used as a fixed value for offset processing. 2) Logging curve smoothing.

Through this step, the two well logs can be roughly synchronized.

104. Attribute extraction

The attributes of the two log curves after the initial migration are extracted, the first log curve is selected as the reference curve 201, and the second log curve is used as the target curve 202, and one or more curve attributes to get the anchor point pairs of the two logging curves;

As such, this step identifies one or more curve-specific properties, such as extrema, inflection points, by comparing the reference curve with the target curve. These attributes can be defined as the anchor points of the target curve 202, and the attribute identification is applied by Law. Multiple attributes are defined on a given curve, such as the anchor points 301, 302, 303 and additional attribute anchor points 304, 305 of the reference curve 201 in FIG. The optimization method finds the corresponding points on the corresponding reference curve to form anchor point pairs. Suppose the first curve is /> , the second curve is /> , /> The calculation formula is: /> In the formula: is the depth, /> yes /> on average, /> yes /> on average, /> is about /> function, /> its about The function.

On the reference curve 201 along Direction sliding window, extracting a sequence of /> sample, get the corresponding data. For example, the anchor points 301, 302, and 303 on the reference curve 201 in Fig. 2 correspond to the anchor points 401, 402, 403, and the anchor points 304, 305 correspond to the anchor points 404, 405, forming a series of anchor point pairs.

In order to avoid false matching, a multi-scale method is used to find suitable anchor point pairs using windows of different sizes to obtain an optimal solution. The number of windows can be defined as 2 or 3 as many as desired. If any anchor pair under any selection window cannot match, it is considered an invalid anchor pair. By using a variety of different window sizes, multiple optimal positions on the curve 201 corresponding to the anchor points on the curve 202 can be obtained (the optimal position refers to the optimal offset to which most of the eigenvalues of the two curves can correspond quantity). If the position of the curve 201 is the same under multiple window sizes, then the anchor point pair under this depth will be designated and saved.

105. Refined offset

In the case of one or more anchor point definitions, the refined migration can be independently selected to execute the migration under the anchor point depth of the curve 201 or the curve 202. For the deformed curve, the refined migration can be performed multiple times, for example, the first After the second refinement migration is executed, the execution result is then executed for the second refinement migration. The second time focuses on the invalid anchor points in the first refinement migration. Such an operation can improve the curve matching degree, and the final anchor point pair can be generated through two refinement migrations, and a depth migration chart 106 will be generated. The generated depth offset graph 106 can be used to change or move the anchor point depth of curve 202 corresponding to curve 201 . When applying the depth migration graph to the second pass curve 202, the curve can be stretched or compressed.

106. Apply Depth Offset Chart

Apply the generated depth migration chart to other curves in the second survey to realize the standardization of all curves in the second well logging data;

107. Data analysis and reservoir oil and gas evaluation

After the curve is standardized, data analysis and reservoir oil and gas evaluation are carried out on the data. The standardized logging curve can be used for stratigraphic correlation, sedimentary evolution, fault analysis, etc., and can also be applied in engineering, such as determining perforation depth and coring Horizon, stratum test horizon.

The standardization of well logging curves is to eliminate the systematic errors generated during the process of well logging data acquisition. Through curve standardization and correction, the well logging curve data corresponding to each well target layer have the same average value or similar frequency distribution, which provides a good foundation for subsequent reservoir evaluation and reservoir geology. The necessary basic work in the research.

As shown in Figure 3, the results show that after standardization, the qualification rate of the curves increases by more than 30%, which improves the precision and accuracy of logging interpretation, and accurately extracts various useful geological information from the logging curves. Significantly improved, it has a certain reference value for the standardization of logging curves in old well areas of oilfields.

Example 2:

Referring to FIG. 4 , the logging curve standardization device based on multi-window anchor points provided by this embodiment includes a processor 41, a memory 42, and a computer program 43 stored in the memory 42 and operable on the processor 41 , such as a multi-window anchor-based log normalization procedure. When the processor 41 executes the computer program 43, the steps in the first embodiment above are realized, for example, the steps described in FIG. 1 .

Exemplarily, the computer program 43 can be divided into one or more modules/units, and the one or more modules/units are stored in the memory 42 and executed by the processor 41 to complete this invention. The one or more modules/units may be a series of computer program instruction segments capable of accomplishing specific functions, and the instruction segments are used to describe the operation of the computer program 43 in the multi-window anchor point-based logging curve standardization device Implementation process.

The log standardization device based on multi-window anchor points can be computing equipment such as desktop computers, notebooks, palmtop computers, and cloud servers. The logging curve standardization device based on multi-window anchor points may include, but not limited to, a processor 41 and a memory 42 . Those skilled in the art can understand that Fig. 4 is only an example of the logging curve standardization device based on the multi-window anchor point, and does not constitute a limitation of the logging curve normalization device based on the multi-window anchor point, and may include more or more than the illustration Fewer components, or a combination of certain components, or different components, for example, the logging curve standardization device based on multi-window anchor points may also include input and output devices, network access devices, buses, and the like.

The so-called processor 41 may be a central processing unit (Central Processing Unit, CPU), and may also be other general-purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), Off-the-shelf programmable gate array (Field Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor, or the processor may be any conventional processor, or the like.

The memory 42 may be an internal storage unit of the multi-window anchor point-based logging curve normalization device, for example, a hard disk or a memory of the multi-window anchor point-based well logging curve normalization device. The memory 42 can also be an external storage device of the logging curve standardization device based on multi-window anchor points, for example, a plug-in hard disk equipped on the multi-window anchor point-based logging curve standardization device, a smart memory card (SmartMedia Card, SMC), Secure Digital (Secure Digital, SD) card, Flash Card (Flash Card), etc. Further, the memory 42 may also include both an internal storage unit and an external storage device of the multi-window anchor point-based logging curve normalization device. The memory 42 is used to store the computer program and other programs and data required by the logging curve standardization device based on multi-window anchor points. The memory 42 can also be used to temporarily store data that has been output or will be output.

Example 3:

This embodiment provides a computer-readable storage medium, where the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method described in Embodiment 1 are implemented.

The computer readable medium may be any means that can contain, store, communicate, propagate or transport the program for use by or in conjunction with an instruction execution system, apparatus or device. More specific examples (non-exhaustive list) of computer-readable media include the following: electrical connection with one or more wires (electronic device), portable computer disk case (magnetic device), random access memory (RAM), Read Only Memory (ROM), Erasable and Editable Read Only Memory (EPROM or Flash Memory), Fiber Optic Devices, and Portable Compact Disc Read Only Memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program can be printed, for example by optically scanning the paper or other medium, followed by editing, interpretation or other suitable means if necessary The process then obtains the program electronically and stores it in the computer memory.

The above-mentioned embodiments are only to illustrate the technical concept and characteristics of the present invention, and its purpose is to enable those of ordinary skill in the art to understand the content of the present invention and implement it accordingly, and cannot limit the protection scope of the present invention. All equivalent changes or modifications made according to the essence of the content of the present invention shall fall within the protection scope of the present invention.

Claims (8)

1. a kind of logging curve standardization method based on multi-window anchor point, it is characterized in that, comprises the steps: 101. Import logging data, the logging data includes a logging curve in the first logging data and a logging curve in the second logging data, and the two logging curves are the same type of logging curves ; 102. Carry out curve preprocessing on the two imported well logging curves, so that the sampling rates of the two well logging curves are consistent, and obtain the two preprocessed well logging curves; 103. Perform initial offset processing on the two preprocessed logging curves; 104. Perform attribute extraction on the two logging curves after the initial migration, select a logging curve in the first logging data as the reference curve, and select a logging curve of the same type in the second logging data as the target Curve, identify one or more curve attributes by comparing the reference curve and the target curve, and obtain the anchor point pair of the two logging curves; 105. In the case of obtaining the anchor point pairs of the two logging curves, choose to execute the depth migration corresponding to the anchor point of the reference curve or the target curve, generate the final anchor point pair, and generate a depth migration chart; 106. Apply the generated depth migration chart to other curves in the second well logging data, so as to realize the standardization operation of all the well logging curves of the second well logging data. 2. the log standardization method based on multi-window anchor point as claimed in claim 1, is characterized in that, also comprises the steps: 107. After all logging curves are standardized, perform data analysis and reservoir oil and gas evaluation. 3. The logging curve standardization method based on multi-window anchor points as claimed in claim 1, wherein in step 102, the curve preprocessing comprises: 1) data resampling, changing the sampling rate of the data to Set the interval; 2) Suppress the interference part of the two data. 4. the logging curve standardization method based on multi-window anchor points as claimed in claim 1, is characterized in that, in step 104, what described attribute extraction adopts is method, assuming that the logging curve in the first logging data is /> , the logging curve in the second logging data is /> , /> The calculation formula is: /> Where: /> is the depth, /> yes /> on average, /> yes /> on average, /> is about /> function, /> is about /> The function; along the reference curve Direction sliding window, extracting a sequence of /> sample, get the corresponding /> data, forming a series of anchor pairs. 5. The logging curve standardization method based on multi-window anchor points according to claim 3, characterized in that, in step 103, the initial offset processing of the preprocessed curve includes performing: 1) calculating Correlation coefficients of the two well logging curves belonging to the first and second well logging data respectively, and then perform initial offset processing with a fixed value; 2) Smooth the two well logging curves. 6. the logging curve standardization method based on multi-window anchor points as claimed in claim 1, is characterized in that, described step 104 also comprises: utilize the window of different sizes to find suitable anchor point pair, obtain optimum solution; If any anchor pair under any selection window cannot match, it is considered an invalid anchor pair. 7. A log standardization device based on multi-window anchor points, comprising a memory, a processor, and a computer program stored in the memory and operable on the processor, wherein the processor executes The computer program realizes the steps of the method according to any one of claims 1-6. 8. A computer-readable storage medium, the computer-readable storage medium storing a computer program, characterized in that, when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.