A method of sedimentary facies delineation

Abstract

The present application relates to a kind of sedimentary facies delineation method, comprising: S1, the three-dimensional seismic data of study area and the well logging data of drilled well are acquired, in combination with the three-dimensional seismic data and the well logging data, the reservoir top and bottom interface of the reservoir of the reservoir sand body of the study area is tracked;S2, according to the top and bottom interface of the reservoir sand body, based on three-dimensional seismic data, the sensitive seismic attribute of the reservoir sand body reservoir is solved;S3, according to the sensitive seismic attribute of the reservoir sand body reservoir, obtain the sensitive seismic attribute of the reservoir sand body reservoir after primary optimization processing and plane sedimentary system boundary information;S4, according to the sensitive seismic attribute of the reservoir sand body reservoir after primary optimization processing, obtain the sensitive seismic attribute of the reservoir sand body reservoir after secondary optimization processing and the main flow line information of the internal river channel of sedimentary system;S5, according to the plane sedimentary system boundary information, the main flow line information of the internal river channel of sedimentary system, in combination with the three-dimensional seismic data, obtain fine plane sedimentary facies.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas exploration and development, and in particular to a method for constraining sedimentary facies characterization based on seismic attribute hierarchical optimization processing. Background Art

[0002] Sedimentary facies is the sum of sedimentary lithologic characteristics, paleontological characteristics, and geochemical characteristics. Sedimentary facies analysis is an important basic work in oil and gas exploration and development.

[0003] At present, the sedimentary facies analysis of existing technologies mainly adopts the "point-line-plane" research approach: first, single-well sedimentary facies analysis is carried out based on well cores and logging curves; second, well-connected profiles in the study area are selected to carry out inter-well sedimentary phase comparative analysis; finally, combined with seismic attributes and well-seismic analysis, the existing seismic attribute bodies are manually delineated based on geological knowledge to carry out planar sedimentary facies analysis.

[0004] However, the accuracy of this method's sedimentary facies analysis depends largely on the number of wells drilled in the study area and the researchers' experience interpreting seismic attributes. Furthermore, manual delineation often relies heavily on the subjective judgment of technicians, often resulting in low map accuracy and, consequently, low sedimentary facies identification accuracy due to factors such as a small number of wells drilled, a small number of sampling points, and varying levels of technical expertise. Existing sedimentary facies analysis methods struggle to meet the demands of offshore development, given the sparse well patterns found in offshore oil and gas fields (well spacings typically greater than 1000 meters in the early stages, reaching 200 to 500 meters in some areas during the mid- to late stages).

[0005] Therefore, it is necessary to make full use of 3D seismic data and well data to establish a more refined sedimentary facies characterization method. Summary of the Invention

[0006] In response to the above problems, the present invention provides a sedimentary facies characterization method that can fully utilize three-dimensional seismic data to carry out detailed characterization of sedimentary facies under offshore sparse well pattern conditions.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present application provides a method for characterizing a sedimentary phase, the method comprising:

[0009] S1, obtaining three-dimensional seismic data and well logging data of the wells that have been drilled in the study area, and tracing the top and bottom interfaces of the reservoir sand body in the study area by combining the three-dimensional seismic data and the well logging data;

[0010] S2, obtaining the sensitive seismic attributes of the reservoir sand body based on the top and bottom interfaces of the reservoir sand body and the three-dimensional seismic data;

[0011] S3, obtaining the sensitive seismic attributes of the reservoir sand body and reservoir layer and the planar sedimentary system boundary information after primary optimization processing according to the sensitive seismic attributes of the reservoir sand body and reservoir layer;

[0012] S4, obtaining, based on the sensitive seismic attributes of the reservoir sand body after the primary optimization processing, the sensitive seismic attributes of the reservoir sand body after the secondary optimization processing and the information of the main stream line of the river channel inside the sedimentary system;

[0013] S5, obtaining fine planar sedimentary facies based on the planar sedimentary system boundary information, the main stream line information of the internal river channel of the sedimentary system, and the three-dimensional seismic data.

[0014] In one implementation, the step S2 includes:

[0015] Extract seismic attributes based on 3D seismic data, using the reservoir top and bottom interfaces interpreted by 3D seismic data as constraints;

[0016] Based on the geological stratification corresponding to the reservoir top and bottom interfaces and the interaction between wells and seismic data, the thickness of the drilled reservoir sand bodies is calculated;

[0017] Based on the aforementioned extracted seismic attributes and the statistically analyzed thickness of the drilled reservoir sand bodies, a correlation analysis is performed on the seismic attributes and the thickness of the reservoir sand bodies to select the sensitive seismic attributes of the reservoir sand bodies.

[0018] In one implementation, S3 includes:

[0019] According to the selected reservoir sand body sensitive seismic attributes, the reservoir sand body reservoir sensitive seismic attributes of the primary optimization processing are obtained;

[0020] According to the sensitive seismic attributes of the reservoir sand body after primary optimization, the maximum curvature of the sensitive seismic attributes of the reservoir sand body after optimization is obtained;

[0021] According to the optimized reservoir sand body reservoir sensitive seismic attributes and the maximum curvature of the reservoir sand body reservoir sensitive seismic attributes, a superposition map of the primary optimized reservoir sand body reservoir sensitive seismic attributes and the maximum curvature is prepared;

[0022] Delineate the boundaries of the target layer's sedimentary system.

[0023] In one implementation, S4 includes:

[0024] According to the selected reservoir sand body sensitive seismic attributes, the secondary optimized reservoir sand body reservoir sensitive seismic attributes are obtained;

[0025] According to the sensitive seismic attributes of the reservoir sand body after the secondary optimization, the maximum curvature of the sensitive seismic attributes of the reservoir sand body after the secondary optimization is obtained;

[0026] The reservoir sensitive seismic attribute of the secondary-optimized reservoir sand body is superimposed with the maximum curvature map.

[0027] The main stream line of the channel in the sedimentary system of the target layer is outlined.

[0028] In an implementation manner, the primary-optimization processing comprises:

[0029] According to the selected reservoir sand body sensitive seismic attribute, a first set of smoothing parameters is set to perform smoothing processing on the reservoir sand body sensitive seismic attribute, and a series of processed reservoir sand body sensitive seismic attributes are obtained.

[0030] According to the geological understanding, the smoothed reservoir sand body sensitive seismic attributes are compared and analyzed, and a seismic attribute capable of reflecting the planar distribution of the sedimentary system is selected as the reservoir sand body reservoir sensitive seismic attribute of the primary-optimization processing.

[0031] In an implementation manner, the secondary-optimization processing comprises:

[0032] According to the selected reservoir sand body sensitive seismic attribute, a second set of smoothing parameters is set to perform smoothing processing on the reservoir sand body sensitive seismic attribute, and a series of processed reservoir sand body sensitive seismic attributes are obtained, wherein the value of the second set of smoothing parameters is smaller than that of the first set of smoothing parameters.

[0033] According to the geological understanding, the smoothed reservoir sand body sensitive seismic attributes are compared and analyzed, and a seismic attribute capable of reflecting the planar distribution of the channel in the sedimentary system is selected as the reservoir sand body reservoir sensitive seismic attribute of the secondary-optimization processing.

[0034] In an implementation manner, in S5, the following steps are included:

[0035] According to the boundary of the sedimentary system of the target layer and the main stream line of the channel in the sedimentary system of the target layer, a superimposed map of the reservoir sand body reservoir sensitive seismic attribute, the boundary of the sedimentary system of the target layer and the main stream line of the channel in the sedimentary system of the target layer is made.

[0036] The seismic attribute is calibrated according to the actual drilling result of the drilled well.

[0037] The fine planar sedimentary facies is outlined.

[0038] In a second aspect, a computer readable storage medium is provided, which stores a computer program. The computer program is executed by a processor to control a device where the processor is located to implement the sedimentary facies delineation method in the first aspect.

[0039] In a third aspect, a computer device is provided, which includes a memory, a processor and a computer program stored in the memory and executable on the processor. The processor implements the sedimentary facies delineation method in the first aspect when executing the computer program.

[0040] The present invention discloses a method for finely characterizing sedimentary facies by using hierarchical optimization processing of seismic attributes to constrain them. This method uses three-dimensional seismic data, combined with well-seismic data, to track and interpret the top and bottom interfaces of reservoir sand bodies. Combined with the actual drilling of sand body thickness, the sensitive seismic attributes of the reservoir are analyzed. Based on the seismic sensitive attributes of the reservoir after hierarchical optimization processing, the boundaries of the sedimentary system and the main stream lines of the sedimentary system are obtained as constraints. Combined with actual drilling and logging phase analysis, the sedimentary facies are finely characterized, thereby guiding the deployment and optimization of development well patterns and providing important technical support for the efficient development and program adjustment of underground oil and gas reservoirs. Furthermore, it has the following advantages:

[0041] (1) Using a hierarchical analysis approach, we first determine the sedimentary system boundary based on the sensitive seismic attributes of the reservoir sand bodies processed by the primary optimization process, completing the first-level sedimentary facies analysis. We then combine the sensitive seismic attributes of the reservoir sand bodies processed by the secondary optimization process to complete the second-level characterization of the main stream of the sedimentary system. Finally, we use the sedimentary system boundary and the main stream of the sedimentary system as constraints, combined with the information of the drilled single wells, to compile a detailed sedimentary facies. This not only adapts to the complex sedimentary laws of the internal structural hierarchy of the fluvial reservoir, but also improves the accuracy of the qualitative characterization of reservoir connectivity.

[0042] (2) The well-seismic combined analysis method is adopted to fully utilize the rich three-dimensional seismic information to constrain the fine characterization of sedimentary facies, which makes up for the shortcomings of the sedimentary facies fine characterization analysis method based mainly on well information under the conditions of sparse offshore well networks, effectively reduces the uncertainty of sedimentary facies analysis, and at the same time improves the prediction efficiency of sedimentary facies analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A flowchart of a technology for fine characterization of sedimentary facies constrained by hierarchical optimization processing of seismic attributes provided in an embodiment of the present invention;

[0044] Figure 2 A schematic diagram of the top and bottom interfaces of a reservoir sand body tracked and interpreted based on three-dimensional seismic data provided by an embodiment of the present invention;

[0045] Figure 3 The embodiment of the present invention provides a method for obtaining a plane map of reservoir sensitive seismic attributes based on three-dimensional seismic data;

[0046] Figure 4 The reservoir sensitive seismic attributes, seismic attribute change rates and sedimentary system boundary plane diagrams of the primary optimization process provided by the embodiment of the present invention;

[0047] Figure 5 The reservoir sensitive seismic attributes, seismic attribute change rates, and planar diagram of the main stream of the sedimentary system through the secondary optimization process provided by the embodiment of the present invention;

[0048] Figure 6A detailed sedimentary phase plan view provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0049] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present invention.

[0050] In view of the defects and problems of the prior art, the present application provides a deposition phase characterization method, the method comprising:

[0051] S1, obtaining three-dimensional seismic data and well logging data of the wells that have been drilled in the study area, and tracing the top and bottom interfaces of the reservoir sand body in the study area by combining the three-dimensional seismic data and the well logging data;

[0052] S2, obtaining the sensitive seismic attributes of the reservoir sand body based on the top and bottom interfaces of the reservoir sand body and the three-dimensional seismic data;

[0053] S3, obtaining the sensitive seismic attributes of the reservoir sand body and reservoir layer and the planar sedimentary system boundary information after primary optimization processing according to the sensitive seismic attributes of the reservoir sand body and reservoir layer;

[0054] S4, obtaining, based on the sensitive seismic attributes of the reservoir sand body after the primary optimization processing, the sensitive seismic attributes of the reservoir sand body after the secondary optimization processing and the information of the main stream line of the river channel inside the sedimentary system;

[0055] S5, obtaining fine planar sedimentary facies based on the planar sedimentary system boundary information, the main stream line information of the internal river channel of the sedimentary system, and the three-dimensional seismic data.

[0056] The above-mentioned primary optimization process includes:

[0057] According to the selected reservoir sand body sensitive seismic attributes, relatively large smoothing parameter values ​​are set to smooth the reservoir sand body sensitive seismic attributes to obtain a series of processed reservoir sand body sensitive seismic attributes;

[0058] Based on geological understanding, the sensitive seismic attributes of the reservoir sand bodies after smoothing were compared and analyzed, and the seismic attributes that can reflect the planar distribution of the sedimentary system were selected as the sensitive seismic attributes of the reservoir sand bodies for primary optimization.

[0059] Secondary optimization processing, including:

[0060] According to the selected reservoir sand body sensitive seismic attributes, different smaller second smoothing parameter values ​​are set to smooth the reservoir sand body sensitive seismic attributes to obtain a series of processed reservoir sand body sensitive seismic attributes;

[0061] Based on geological understanding, the sensitive seismic attributes of the reservoir sand bodies after smoothing were compared and analyzed, and the seismic attributes that can reflect the planar distribution of the river channels within the sedimentary system were selected as the sensitive seismic attributes of the reservoir sand bodies for secondary optimization.

[0062] The above method flow is described in more detail in the following embodiments in conjunction with the accompanying drawings of the present invention.

[0063] Example 1

[0064] Example 1 provides a method for fine characterization of sedimentary facies by hierarchical optimization of seismic attributes, such as Figure 1 As shown, the following steps are included:

[0065] Step A: Using 3D seismic data, combining well and seismic data, interactively tracking and interpreting the top and bottom interfaces of the reservoir sand body;

[0066] Depend on Figure 2 It can be seen that based on the 3D seismic data, the top and bottom interfaces of the target reservoir sand body can be tracked and interpreted.

[0067] Step B, obtaining the sensitive seismic attributes of the reservoir sand body based on the 3D seismic data, specifically comprises the following steps:

[0068] Step B1: Taking SQ4 as an example, the top and bottom interfaces of the SQ4 reservoir sand body are used as seismic time windows, and the reservoir seismic attributes of SQ4 are extracted based on 3D seismic data;

[0069] Step B2: Using the top and bottom interfaces of the SQ4 reservoir sand body interpreted by tracing as constraints, calculate the actual drilling sand body thickness;

[0070] Step B3: Perform correlation analysis on the seismic attributes extracted by SQ4 and reservoir thickness, select reservoir-sensitive seismic attributes, and calibrate the attributes based on the actual drilled reservoir thickness;

[0071] Depend on Figure 3 It can be seen that the SQ4 reservoir is distributed in a northwest-southeast direction as a whole, mainly in the central and northern part of the study area, among which the reservoir in the north is more developed.

[0072] Step C, based on the initial reservoir sensitivity attributes, obtains the reservoir sand body sensitive seismic attributes and plane sedimentary system boundary information after primary optimization processing, and the specific steps are as follows:

[0073] Step C1: Based on the initial reservoir sand body sensitive seismic attributes obtained in step B3, the initial reservoir sand body sensitive seismic attributes are smoothed using appropriate smoothing parameters to obtain primary optimized reservoir sand body reservoir sensitive seismic attributes;

[0074] Step C2: Calculate the maximum curvature of the reservoir sand body reservoir sensitive seismic attribute processed by the SQ4 primary optimization process, and obtain the change rate of the reservoir sensitive seismic attribute;

[0075] Step C3: Optimize the change rate of the sensitive seismic attributes of the SQ4 reservoir to obtain the boundary information of the planar sedimentary system;

[0076] Step C4: Based on the SQ4 plane sedimentary system boundary information, generate the reservoir sand body sensitive seismic attributes and sedimentary system boundary information of the SQ4 primary optimization process, and delineate the SQ4 sedimentary system boundary.

[0077] Depend on Figure 4 It can be seen that during the SQ4 period, four fan delta sedimentary bodies were developed, extending nearly northwest-southeast, and sheet sand and distal sand bar deposits were developed at the front end of the fan delta sedimentary bodies.

[0078] Step D, based on the initial reservoir sensitive attributes, obtains the secondary optimized reservoir sand body reservoir sensitive seismic attributes and the main stream line information of the internal river channel of the sedimentary system, and the specific steps are as follows:

[0079] Step D1: Based on the initial reservoir sand body sensitive seismic attributes obtained in step B3, the initial reservoir sand body sensitive seismic attributes are smoothed using appropriate smoothing parameters to obtain secondary optimized reservoir sand body reservoir sensitive seismic attributes;

[0080] Step D2: Calculate the maximum curvature of the reservoir sand body sensitive seismic attribute processed by the SQ4 secondary optimization process, and obtain the change rate of the reservoir sensitive seismic attribute;

[0081] Step D3: Optimize the change rate of the sensitive seismic attributes of the SQ4 reservoir to obtain the channel boundary information within the sedimentary system;

[0082] Step D4: Based on the internal channel boundary information of the SQ4 sedimentary system, the reservoir sand body sensitive seismic attributes, sedimentary system and internal channel boundary information of the SQ4 secondary optimization processing are generated, and the main channel line of the SQ4 sedimentary system is drawn.

[0083] Depend on Figure 5 It can be seen that during the SQ4 period, four fan delta sedimentary bodies developed in a nearly northwest-southeast direction. Multiple branching channels were developed inside each fan delta sedimentary body, and sheet sand and distal sand bar deposits were developed at the front end of the fan delta sedimentary body.

[0084] Step E: Combine well and seismic data to obtain fine-scale planar sedimentary facies. The specific steps are as follows:

[0085] Step E1: Based on the analysis results of steps C4 and D4, a superimposed map of the reservoir sand body sensitive seismic attributes, the boundary of the target layer sedimentary system, and the main stream line of the sedimentary system is prepared;

[0086] Step E2: Based on the analysis results of step E1, calibrate the seismic attributes according to the actual drilling results;

[0087] Step E3: Based on the analysis results of step E2, combine well and seismic data to outline the fine planar sedimentary facies.

[0088] Depend on Figure 6 It can be seen that during the SQ4 period, four fan delta sedimentary bodies developed in a nearly northwest-southeast direction. Multiple branching channels were developed within each fan delta sedimentary body, lacustrine mudstones were developed between each fan delta sedimentary body, and lacustrine mudstones, sheet sands, and distal sandbar deposits were developed at the front end of the fan delta sedimentary body.

[0089] In the several embodiments provided by the present invention, it should be understood that the disclosed methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the above units is merely a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interface, indirect coupling or communication connection of devices or units, which may be electrical, mechanical or other forms.

[0090] The above-mentioned integrated unit implemented in the form of a software functional unit can be stored in a computer-readable storage medium. The above-mentioned software functional unit is stored in a storage medium and includes a number of instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) or a processor to perform some of the steps of the above-mentioned methods of various embodiments of the present invention. The aforementioned storage medium includes: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, etc., various media that can store program code.

[0091] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A sedimentary phase characterization method, characterized in that: The method comprises: S1, obtaining three-dimensional seismic data and well logging data of the wells that have been drilled in the study area, and tracing the top and bottom interfaces of the reservoir sand body in the study area by combining the three-dimensional seismic data and the well logging data; S2, obtaining sensitive seismic attributes of the reservoir sand body reservoir based on the top and bottom interfaces of the reservoir sand body reservoir and the three-dimensional seismic data; S3, obtaining the sensitive seismic attributes of the reservoir sand body and reservoir layer and the planar sedimentary system boundary information after primary optimization processing according to the sensitive seismic attributes of the reservoir sand body and reservoir layer; S4, obtaining, based on the sensitive seismic attributes of the reservoir sand body after the primary optimization processing, the sensitive seismic attributes of the reservoir sand body after the secondary optimization processing and the information of the main stream line of the river channel inside the sedimentary system; S5, obtaining fine planar sedimentary facies based on the planar sedimentary system boundary information, the main stream line information of the internal river channel of the sedimentary system, and the three-dimensional seismic data.

2. The deposition phase characterization method according to claim 1, characterized in that: Said S2 includes: Extract seismic attributes based on 3D seismic data, using the reservoir top and bottom interfaces interpreted by 3D seismic data as constraints; Based on the geological stratification corresponding to the reservoir top and bottom interfaces and the interaction between wells and seismic data, the thickness of the drilled reservoir sand bodies is calculated; Based on the aforementioned extracted seismic attributes and the statistically analyzed thickness of the drilled reservoir sand bodies, a correlation analysis is performed on the seismic attributes and the thickness of the reservoir sand bodies to select the sensitive seismic attributes of the reservoir sand bodies.

3. The deposition phase characterization method according to claim 2, characterized in that: In S3, this includes: According to the selected reservoir sand body sensitive seismic attributes, the reservoir sand body reservoir sensitive seismic attributes of the primary optimization processing are obtained; According to the sensitive seismic attributes of the reservoir sand body after primary optimization, the maximum curvature of the sensitive seismic attributes of the reservoir sand body after optimization is obtained; According to the optimized reservoir sand body reservoir sensitive seismic attributes and the maximum curvature of the reservoir sand body reservoir sensitive seismic attributes, a superposition map of the primary optimized reservoir sand body reservoir sensitive seismic attributes and the maximum curvature is prepared; Delineate the boundaries of the target layer's sedimentary system.

4. The deposition phase characterization method according to claim 3, characterized in that: In S4, it includes: According to the selected reservoir sand body sensitive seismic attributes, the secondary optimized reservoir sand body reservoir sensitive seismic attributes are obtained; According to the sensitive seismic attributes of the reservoir sand body after the secondary optimization, the maximum curvature of the sensitive seismic attributes of the reservoir sand body after the secondary optimization is obtained; Produce a superposition map of sensitive seismic attributes and maximum curvature of the reservoir sand body after secondary optimization; Delineate the main channel line within the target layer sedimentary system.

5. The deposition phase characterization method according to claim 4, characterized in that: The primary optimization process includes: According to the selected reservoir sand body sensitive seismic attributes, a first smoothing parameter set is set to perform smoothing processing on the reservoir sand body sensitive seismic attributes, thereby obtaining a series of processed reservoir sand body sensitive seismic attributes; Based on geological understanding, the sensitive seismic attributes of the reservoir sand bodies after smoothing were compared and analyzed, and the seismic attributes that can reflect the planar distribution of the sedimentary system were selected as the sensitive seismic attributes of the reservoir sand bodies for primary optimization.

6. The deposition phase characterization method according to claim 5, characterized in that: The secondary optimization process includes: According to the selected reservoir sand body sensitive seismic attributes, a second smoothing parameter set is set to smooth the reservoir sand body sensitive seismic attributes to obtain a series of processed reservoir sand body sensitive seismic attributes, wherein the value of the second smoothing parameter set is smaller than that of the first smoothing parameter set; Based on geological understanding, the sensitive seismic attributes of the reservoir sand bodies after smoothing were compared and analyzed, and the seismic attributes that can reflect the planar distribution of the river channels within the sedimentary system were selected as the sensitive seismic attributes of the reservoir sand bodies for secondary optimization.

7. The deposition phase characterization method according to claim 4, characterized in that: In S5, including: Based on the target layer sedimentary system boundary and the internal river channel mainstream line of the target layer sedimentary system, a superposition map of the reservoir sensitive seismic attributes of the sand body after secondary optimization, the target layer sedimentary system boundary and the internal river channel mainstream line of the sedimentary system is produced; Calibrate seismic attributes based on actual drilling results of existing wells; Delineate the fine-scale planar sedimentary facies.

8. A computer-readable storage medium, characterized in that A computer program is stored, and the computer program is executed by a processor to control the device where the processor is located to implement the deposition phase characterization method according to any one of claims 1 to 7.

9. A computer device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the method implements the deposition phase characterization method according to any one of claims 1 to 7 when the processor executes the computer program.

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