Sequence division method and device under seismic data volume frequency division optimization

Abstract

The invention relates to a sequence division method and device under seismic data volume frequency division optimization, and the method comprises the steps: carrying out the wavelet transformation of a seismic data volume containing a target interval, and determining a sensitive frequency range corresponding to a target layer sand body according to the seismic data volume after the wavelet transformation; extracting a plurality of frequency division seismic data volumes in a sensitive frequency range, and screening a target frequency division amplitude seismic attribute volume with an optimal sand body recognition effect from the plurality of frequency division seismic data volumes; performing three-dimensional gridding processing on the target frequency division amplitude seismic data volume; extracting a grid amplitude value of a well passing track based on the grid-processed frequency division amplitude seismic data body, and establishing an amplitude value curve; and calibrating the position of the five-level sequence stratigraphic framework according to the amplitude value curve to obtain a calibrated sequence stratigraphic framework. According to the method, the problem of establishing the five-level sequence stratigraphic framework on the seismic section of the continental deposition reservoir is solved, a data basis is provided for subsequent reservoir inversion, the inversion result is more objective and accurate, and the resolution ratio is higher.

Description

Technical Field

[0001] The invention relates to a layer sequence division method and device under the frequency division optimization of seismic data volume. Background Art

[0002] High-precision sequence identification plays a very important role in oilfield exploration and development. Fine sequence division results can greatly improve research accuracy, especially reservoir inversion results under high-precision framework control are of great significance for detailed reservoir research. Summary of the invention

[0003] In order to enrich the sequence division method and realize the establishment of a five-level sequence stratigraphic framework on the seismic section, the present invention proposes a sequence division method and device under the frequency division optimization of seismic data volume. The technical solution proposed by the present invention is as follows:

[0004] In a first aspect, the present invention provides a method for layer sequence division under frequency division optimization of a seismic data volume, comprising:

[0005] Performing wavelet transformation on the seismic data volume containing the target layer segment to obtain a seismic data volume after wavelet transformation;

[0006] Determine the sensitive frequency range corresponding to the target layer sand body according to the seismic data body after the wavelet transformation;

[0007] Extracting a plurality of frequency-divided seismic data volumes within the sensitive frequency range, selecting a frequency-divided amplitude seismic data volume with the best sand body identification effect from the plurality of frequency-divided seismic data volumes, and obtaining a target frequency-divided amplitude seismic attribute volume;

[0008] Performing three-dimensional gridding processing on the target frequency-divided amplitude seismic data volume to obtain a frequency-divided amplitude seismic data volume after gridding processing;

[0009] Extracting grid amplitude values ​​of the well trajectory based on the gridded frequency-divided amplitude seismic data volume, and establishing an amplitude value curve;

[0010] A pre-established fourth-order sequence stratigraphic framework is obtained, and the fifth-order sequence stratigraphic framework position is calibrated on the fourth-order sequence stratigraphic framework according to the amplitude value curve to obtain a calibrated sequence stratigraphic framework.

[0011] In some embodiments, the method further comprises:

[0012] Under the control of the position of the fourth-level sequence stratigraphic framework, the position corresponding to the fifth-level sequence stratigraphic framework is calibrated in the time-domain seismic data volume based on the calibrated sequence stratigraphic framework to complete the fifth-level sequence tracking.

[0013] In some embodiments, performing wavelet transform on the seismic data volume including the target layer segment to obtain the seismic data volume after wavelet transform includes:

[0014] The seismic data volume containing the target layer is subjected to wavelet transformation by the following formula to obtain the seismic data volume after wavelet transformation:

[0015]

[0016] Where: WT x (a, b) represents the seismic data after wavelet transformation, a represents the scale factor; b represents the translation factor; ψ(t) represents the wavelet function; x(t) represents the seismic data.

[0017] In some embodiments, determining the sensitive frequency range corresponding to the target layer sand body according to the seismic data volume after the wavelet transformation includes:

[0018] Determine the velocity of the target layer sand body according to the seismic data body after the wavelet transformation;

[0019] The sandstone thickness range of the target layer sand body is obtained, and the sensitive frequency range corresponding to the target layer sand body is determined by the following formula according to the sandstone thickness range and the corresponding velocity of the target layer sand body:

[0020] f=V / 4*h

[0021] Where: f represents the sensitive frequency, V represents the longitudinal propagation velocity of seismic waves in the target layer, and h represents the thickness of sandstone.

[0022] In some embodiments, the amplitude seismic data volume within the sensitive frequency range is extracted by:

[0023] By using the sensitive frequency corresponding to the target layer sand body, a plurality of frequency-divided seismic data volumes of a plurality of adjacent frequencies of the sensitive frequency are extracted from the wavelet transformed seismic data volume according to a preset frequency interval.

[0024] In some embodiments, the frequency-divided amplitude seismic data volume with the best sand body identification effect is selected from the multiple frequency-divided amplitude seismic data volumes to obtain the target frequency-divided amplitude seismic attribute volume:

[0025] Extracting amplitude attributes of the plurality of frequency-divided seismic data volumes, and determining a correlation coefficient between the amplitude attributes of the drilled well position and the sandstone thickness;

[0026] The frequency-divided amplitude seismic data volume with the highest correlation coefficient is selected from the multiple frequency-divided amplitude seismic data volumes to obtain a target frequency-divided amplitude seismic attribute volume.

[0027] In some embodiments, the three-dimensional gridding of the target frequency-divided amplitude seismic data volume to obtain the gridded frequency-divided amplitude seismic data volume includes:

[0028] Determine the lateral accuracy of the grid based on the bins of the seismic data volume;

[0029] Determine the vertical accuracy of the grid based on the average thickness of the target layer sand body;

[0030] The target frequency-divided amplitude seismic data volume is subjected to three-dimensional gridding according to the determined grid transverse accuracy and grid longitudinal accuracy, and the amplitude value in the grid is assigned by the following formula to obtain the gridded frequency-divided amplitude seismic data volume:

[0031]

[0032] Where: G represents the geometric mean value of amplitude, X i Represents the amplitude value in the i-th grid, and n represents the number of grids.

[0033] In some embodiments, the fifth-level sequence stratigraphic framework position is calibrated on the fourth-level sequence stratigraphic framework in the following manner to obtain a calibrated sequence stratigraphic framework:

[0034] According to the acquired sand body distribution characteristics and the morphological change characteristics of the amplitude value curve, the fifth-order sequence stratigraphic framework position is calibrated on the fourth-order sequence stratigraphic framework to obtain a calibrated sequence stratigraphic framework.

[0035] In some embodiments, the time domain seismic data volume includes a single well seismic profile; the position corresponding to the fifth-level sequence frame is calibrated in the time domain seismic data volume based on the calibrated sequence stratigraphic framework under the control of the fourth-level sequence stratigraphic framework position, and the fifth-level sequence tracking is completed, including:

[0036] The time-depth conversion is performed on each well layer in the calibrated sequence stratigraphic framework. After the time-depth conversion, the corresponding position of the five-level sequence framework is calibrated on the single well seismic section, and the five-level sequence tracking is completed under the control of the position of the four-level sequence stratigraphic framework.

[0037] In a second aspect, the present invention provides a device for dividing a layer sequence under frequency division optimization of a seismic data volume, comprising:

[0038] A transformation module, used for performing wavelet transformation on the seismic data volume containing the target layer segment to obtain the seismic data volume after wavelet transformation;

[0039] A sensitive frequency range determination module is used to determine the sensitive frequency range corresponding to the target layer sand body according to the seismic data body after the wavelet transformation;

[0040] A screening module is used to extract multiple frequency-divided seismic data volumes within the sensitive frequency range, and screen the frequency-divided amplitude seismic data volume with the best sand body identification effect from the multiple frequency-divided seismic data volumes to obtain the target frequency-divided amplitude seismic attribute volume;

[0041] A gridding processing module, used for performing three-dimensional gridding processing on the target frequency-divided amplitude seismic data volume to obtain the frequency-divided amplitude seismic data volume after gridding processing;

[0042] An amplitude value curve establishment module is used to extract the grid amplitude value of the well trajectory based on the gridded frequency-divided amplitude seismic data volume and establish an amplitude value curve;

[0043] The calibration module is used to obtain a pre-established fourth-order sequence stratigraphic framework, and calibrate the fifth-order sequence stratigraphic framework position on the fourth-order sequence stratigraphic framework according to the amplitude value curve to obtain a calibrated sequence stratigraphic framework.

[0044] In a third aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for layer division under the frequency division optimization of the seismic data volume as described in the first aspect.

[0045] In a fourth aspect, the present invention provides an electronic device, comprising a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus;

[0046] Memory, used to store computer programs;

[0047] The processor is used to implement the layer sequence division method under the frequency division optimization of the seismic data volume as described in the first aspect when executing the program stored in the memory.

[0048] Based on the above technical solution, the beneficial effects of the present invention compared with the prior art are as follows:

[0049] The method for layer division under the frequency division optimization of seismic data provided by the present invention improves the recognition ability of the seismic data body for thin-layer sandstone by performing wavelet transformation on the seismic data body containing the target layer segment; then the sensitive frequency range corresponding to the target layer sand body is determined according to the seismic data body after the wavelet transformation, and multiple frequency division seismic data bodies within the sensitive frequency range are extracted, and the frequency division amplitude seismic attribute body with the best sand body effect is established by using the frequency division optimization technology to obtain the target frequency division amplitude seismic attribute body; three-dimensional gridding is performed on the target frequency division amplitude seismic data body to obtain the frequency division amplitude seismic data body after gridding; based on the gridding The grid amplitude values ​​of the well trajectory are extracted from the frequency-divided amplitude seismic data volume, and an amplitude value curve is established to achieve the establishment of the amplitude value curve along the well trajectory; then, based on the established amplitude value curve, the position of the five-level sequence stratigraphic framework is calibrated on the well, and finally, it is tracked in the seismic data volume to complete the establishment of the five-level sequence stratigraphic framework. In the reservoir inversion, the stratigraphic framework is refined from the oil group (80-100 meters) to the 5th-level sand layer group (20-30 meters), and the research accuracy is improved by about 4-5 times. The difficulty of establishing a five-level sequence stratigraphic framework for continental sedimentary reservoirs on seismic sections has been overcome, which provides a data basis for subsequent reservoir inversion. The inversion results are more objective and accurate with higher resolution.

[0050] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0051] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0053] Figure 1 It is a flow chart of a method for layer sequence division under frequency division optimization of seismic data volume provided by an embodiment of the present invention;

[0054] Figure 2 It is a schematic diagram of calibrating well layers onto seismic data volumes provided by an embodiment of the present invention;

[0055] Figure 3a is a schematic diagram of grid amplitude values ​​of well-crossing trajectories extracted according to an embodiment of the present invention;

[0056] Figure 3b is a schematic diagram of a well trajectory amplitude curve established in an embodiment of the present invention;

[0057] Figure 4 It is a schematic diagram of assigning wellbore velocity data to a grid according to an embodiment of the present invention;

[0058] Figure 5 is a schematic diagram of five-level sequence tracing on a seismic section provided by an embodiment of the present invention;

[0059] Figure 6 It is a structural schematic diagram of a layer sequence division device under the frequency division optimization of a seismic data volume provided by an embodiment of the present invention;

[0060] Figure 7 It is a schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0061] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0062] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0063] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0064] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0065] Existing oil fields are generally continental sedimentary reservoirs, with complex and changeable sand body distribution, generally poor resolution of seismic data, and extremely difficult reservoir prediction. The inventors found in their work that the main method currently used for reservoir prediction is reservoir inversion. When establishing a stratigraphic framework, it is mainly based on tracking the characteristics of the event axis on the seismic profile. The division of the third and fourth level sedimentary cycles is not a big problem, but after being subdivided into five-level sequences, the interference factors on the seismic profile increase, the multi-solution is strong, and the sequence interface division is not detailed, resulting in unsatisfactory seismic inversion results, which cannot meet the inventors' expectations. At present, the establishment of a five-level stratigraphic framework requires overcoming the following technical difficulties:

[0066] (1) How to improve the ability of seismic data to identify thin-layer sandstone.

[0067] (2) How to combine lithology changes with seismic data to achieve a more reasonable five-level sequence division result. The inventors made the present invention after further research and development.

[0068] Embodiment 1

[0069] The embodiment of the present invention provides a method for dividing the layers under the frequency division optimization of the seismic data volume, referring to Figure 1 As shown, including:

[0070] S101, performing wavelet transformation on a seismic data volume including a target layer segment to obtain a seismic data volume after wavelet transformation;

[0071] Wavelet transform is a seismic data processing technology for improving resolution, and has advantages in studying the thickness of thin strata and the discontinuity of geological bodies. The present invention utilizes wavelet transform to improve the recognition ability of seismic data bodies for continental thin interbedded sandstones.

[0072] S102, determining a sensitive frequency range corresponding to a target layer sand body according to the seismic data volume after the wavelet transformation;

[0073] S103, extracting a plurality of frequency-divided seismic data volumes within the sensitive frequency range, selecting a frequency-divided amplitude seismic data volume with the best sand body identification effect from the plurality of frequency-divided seismic data volumes, and obtaining a target frequency-divided amplitude seismic attribute volume;

[0074] S104, performing three-dimensional gridding processing on the target frequency-divided amplitude seismic data volume to obtain a frequency-divided amplitude seismic data volume after gridding processing;

[0075] S105, extracting grid amplitude values ​​of well tracks based on the gridded frequency-divided amplitude seismic data volume, and establishing an amplitude value curve;

[0076] The grid amplitude value of the well track is extracted from the gridded frequency-divided amplitude seismic data volume, and the grid amplitude value of the well track extracted is referenced to Figure 3a As shown, a reference is established based on the amplitude value. Figure 3b The amplitude value curve shown is used to describe the lithology changes and provide a basis for the five-level sequence division.

[0077] S106, obtaining a pre-established fourth-order sequence stratigraphic framework, and calibrating a fifth-order sequence stratigraphic framework position on the fourth-order sequence stratigraphic framework according to the amplitude value curve to obtain a calibrated sequence stratigraphic framework.

[0078] The method for stratigraphic division under frequency division optimization of seismic data provided by the present invention belongs to the field of oil and gas exploitation. In view of the above-mentioned problems, the present invention uses a wavelet transform method to improve the recognition ability of seismic data for thin-layer sandstone, and then establishes a well trajectory amplitude value curve based on the frequency division optimization technology to complete the five-level stratigraphic grid tracking, thereby realizing the fine division of stratigraphic layers combining multiple factors. Specifically, the wavelet transform method in the time-frequency analysis technology is first applied to perform wavelet transform on the seismic data body containing the target layer segment, thereby improving the seismic data body's ability to identify thin-layer sandstone; then, the sensitive frequency range corresponding to the target layer sand body is determined based on the seismic data body after the wavelet transform, and multiple frequency-divided seismic data bodies within the sensitive frequency range are extracted, and the frequency-divided amplitude seismic attribute body with the best sand body effect is established using the frequency-divided optimization technology to obtain the target frequency-divided amplitude seismic attribute body; three-dimensional gridding is performed on the target frequency-divided amplitude seismic data body to obtain the gridded frequency-divided amplitude seismic data body; based on the gridded frequency-divided amplitude seismic data body, the grid amplitude value of the well trajectory is extracted, and an amplitude value curve is established to achieve the establishment of an amplitude value curve along the well trajectory; then, based on the established amplitude value curve, the position of the five-level sequence stratigraphic framework is calibrated on the well, and finally, it is tracked in the seismic data body to complete the establishment of the five-level sequence stratigraphic framework. The five-level sedimentary cycle division results of the present invention are more reasonable. The stratigraphic framework in reservoir inversion is refined from the oil group (80-100 meters) to the 5-level sand layer group (20-30 meters), and the research accuracy is improved by about 4-5 times. The difficulty of establishing a five-level sequence stratigraphic framework for continental sedimentary reservoirs on seismic sections has been overcome, and a data basis has been provided for subsequent reservoir inversion. The inversion results are more objective and accurate, and the resolution is higher. The present invention provides effective technical means and field implementation methods for the fine prediction of continental sedimentary reservoirs. According to the method of the present invention, the fine establishment of a five-level sequence stratigraphic framework in the seismic data body can be achieved, and a more refined stratigraphic framework model is provided for reservoir distribution.

[0079] In a specific embodiment, the method further comprises:

[0080] S107, under the control of the position of the fourth-level sequence stratigraphic framework, based on the calibrated sequence stratigraphic framework, the position corresponding to the fifth-level sequence framework is calibrated in the time-domain seismic data volume to complete the fifth-level sequence tracking.

[0081] In a specific embodiment, the wavelet transform is performed on the seismic data volume containing the target layer segment in step S101 to obtain the seismic data volume after the wavelet transform, including:

[0082] The seismic data volume containing the target layer is subjected to wavelet transformation by the following formula to obtain the seismic data volume after wavelet transformation:

[0083]

[0084] Where: WT x(a, b) represents the seismic data after wavelet transformation, a represents the scale factor, b represents the translation factor, ψ(t) represents the wavelet function, and x(t) represents the seismic data. The scale factor a and the translation factor b are set according to actual needs and are not specifically limited here.

[0085] In a specific embodiment, the step S102 of determining the sensitive frequency range corresponding to the target layer sand body according to the seismic data volume after the wavelet transformation includes:

[0086] S1021, determining the velocity of the target layer sand body according to the seismic data volume after the wavelet transformation;

[0087] S1022, obtaining the sandstone thickness range of the target layer sand body, and determining the sensitive frequency range corresponding to the target layer sand body according to the sandstone thickness range and the corresponding velocity of the target layer sand body by the following formula:

[0088] f=V / 4*h, formula 2;

[0089] Where: f represents the sensitive frequency, V represents the longitudinal propagation velocity of seismic waves in the target layer, and h represents the thickness of sandstone.

[0090] The thickness range of the sandstone of the target layer is counted, and the sensitive frequency range corresponding to the sand body is calculated based on the different sensitivity of different frequencies to sandstones of different thicknesses, combined with the sensitive frequency calculation formula (Formula 2 above). For example, if the velocity of the target layer where the sand body is located is 2000 m / s and the sandstone thickness is 10 meters, then f = 2000 / 4*10 = 50 Hz, and the sensitive frequency of the sand body is around 50 Hz.

[0091] In a specific embodiment, the amplitude seismic data volume within the sensitive frequency range in S103 is extracted in the following manner:

[0092] S1031. Using the sensitive frequency corresponding to the target layer sand body, extract multiple frequency-divided seismic data volumes of multiple adjacent frequencies of the sensitive frequency from the wavelet transformed seismic data volume according to a preset frequency interval.

[0093] Using the sensitive frequency corresponding to the sand body, multiple frequency-divided seismic data bodies of the sensitive frequency and adjacent frequencies are extracted. The above-mentioned preset frequency interval can be set according to actual needs, and the present invention does not make specific limitations. For example, when the sensitive frequency of the known sand body is around 50 Hz, the frequency-divided seismic bodies above or below 50 Hz are extracted respectively, and 5 frequency-divided seismic bodies of 40 Hz, 45 Hz, 50 Hz, 55 Hz, and 60 Hz are extracted respectively at intervals of 5 Hz.

[0094] In a specific embodiment, the frequency-divided amplitude seismic data volume with the best sand body identification effect is selected from the multiple frequency-divided amplitude seismic data volumes to obtain the target frequency-divided amplitude seismic attribute volume, including:

[0095] S1032, extracting the amplitude attributes of the multiple frequency-divided seismic data volumes, and determining the correlation coefficient between the amplitude attributes of the drilled positions and the sandstone thickness;

[0096] S1033: Filter the frequency-divided amplitude seismic data volume with the highest correlation coefficient from the multiple frequency-divided seismic data volumes to obtain a target frequency-divided amplitude seismic attribute volume.

[0097] Extract the amplitude attributes of multiple frequency-divided seismic data volumes, and select the frequency-divided amplitude seismic data volume that best reflects the distribution of sand bodies. Specifically, after determining the correlation coefficients corresponding to each frequency-divided seismic data volume, select the frequency-divided seismic data volume with the highest correlation coefficient from the multiple frequency-divided seismic data volumes to obtain the above-mentioned target frequency-divided amplitude seismic attribute volume. If 5 frequency-divided seismic data volumes are extracted, compare the correlation coefficients of the amplitude attribute values ​​of the drilled positions and the sandstone thickness values. The frequency-divided amplitude seismic data volume with the highest correlation coefficient has the strongest ability to identify sandstone.

[0098] In a specific embodiment, the step S104 described above performs three-dimensional gridding processing on the target frequency-divided amplitude seismic data volume to obtain the gridded frequency-divided amplitude seismic data volume, including:

[0099] S1041, determining the lateral accuracy of the grid according to the bins of the seismic data volume;

[0100] S1042, determining the vertical accuracy of the grid according to the average thickness of the target layer sand body;

[0101] S1043, performing three-dimensional gridding processing on the target frequency-divided amplitude seismic data volume according to the determined grid transverse accuracy and grid longitudinal accuracy, and assigning amplitude values ​​within the grid by the following formula to obtain the gridded frequency-divided amplitude seismic data volume:

[0102]

[0103] Where: G represents the geometric mean value of amplitude, X i Represents the amplitude value in the i-th grid, and n represents the number of grids.

[0104] The selected frequency-division amplitude seismic data volume is processed into three-dimensional grids (refer to Figure 2The horizontal accuracy of the grid is determined according to the lateral heterogeneity of the sand body, which is generally consistent with the bin of the seismic data body. For example, if the bin accuracy of the seismic data body is 25m*25m, the horizontal accuracy of the grid is also 25m*25m; the vertical accuracy of the grid is generally less than 1 / 2 of the average sand body thickness. For example, if the average thickness of the target layer sand body is 2m, the vertical accuracy of the grid should be less than 1m. The grid is assigned values ​​based on the amplitude value of the seismic data body using the geometric mean method (Formula 3 above), because the algorithm results have little impact on extreme values, and the value difference of the amplitude value of the sandstone and mudstone is more reasonable.

[0105] In a specific embodiment, the fifth-level sequence stratigraphic framework position is calibrated on the fourth-level sequence stratigraphic framework in the following manner to obtain the calibrated sequence stratigraphic framework in S106:

[0106] The above four-level sequence stratigraphic framework is obtained in the following way: the sedimentary sequence is a regular periodic repetition of several similar lithologies on the stratigraphic section, or refers to a set of rock combinations with a grain size from coarse to fine and then from fine to coarse from bottom to top. Sedimentary sequences are manifested in different scales and scales and can be divided into different levels. Oilfield geologists are accustomed to using a four-level sequence division scheme. The first-level sequence reflects the changes in ancient water depth, biological combination and sedimentary system, the second-level sequence reflects the repeated sedimentary phases within the same type of sedimentary system, the third-level sequence is an ordered combination of different microphases in the same lithofacies section, and the fourth-level sequence is a grain sequence combination containing at least one relatively coarse lithology layer. Reservoirs can be divided into levels according to different levels of sedimentary sequences. The first to fourth-level sequences roughly correspond to oil-bearing strata, oil layer group, sand layer group and small layer, respectively.

[0107] After obtaining the established fourth-order sequence stratigraphic framework, based on the original fourth-order sequence, according to the obtained sand body distribution characteristics and the morphological change characteristics of the amplitude value curve, the fifth-order sequence stratigraphic framework position is calibrated on the fourth-order sequence stratigraphic framework, and the fifth-order sequence is subdivided to obtain the calibrated sequence stratigraphic framework. Specifically, based on the sandstone distribution, the turning point corresponding to the sandstone distribution position on the amplitude value curve is determined, and the sequence division is performed based on the sandstone and the determined turning point. Figure 4 As shown, the fifth-order sequence is divided according to the distribution of sandstone between the top of the fourth-order sequence interface and the bottom of the fourth-order sequence interface, combined with the turning point of the amplitude value curve; for locations without sandstone distribution (such as between the fifth-order sequence interface ② and the fifth-order sequence interface ③ of the W1 well and the W3 well), the sequence divided according to the adjacent well (W2 well) is extended to divide the fifth-order sequence interface ①, the fifth-order sequence interface ② and the fifth-order sequence interface ③. The division of the five-order sequence is mainly to reflect the amplitude change based on the seismic data. The present invention extracts the grid amplitude value of the well trajectory, establishes an amplitude value curve according to the amplitude value, and combines it with the sand body cycle on the well to achieve well-seismic unification. The five-order sequence division result can achieve vertical distinction in seismic.

[0108] The time domain seismic data volume described in step S107 includes a single well seismic profile. Under the control of the position of the fourth-level sequence stratigraphic framework, the position corresponding to the fifth-level sequence stratigraphic framework is calibrated in the time domain seismic data volume based on the calibrated sequence stratigraphic framework to complete the fifth-level sequence tracking, including:

[0109] S1071. Perform time-depth conversion on each well layer in the calibrated sequence stratigraphic framework. After the time-depth conversion, the corresponding position of the five-level sequence framework is calibrated on the single well seismic section. Under the control of the position of the four-level sequence stratigraphic framework, the five-level sequence tracking is completed.

[0110] After completing the calibration of the position of the five-level sequence stratigraphic framework on the well, the time-depth conversion is performed on each well layer in the calibrated sequence stratigraphic framework to obtain the time domain sequence stratigraphic framework. Based on the time domain sequence stratigraphic framework, the corresponding position of the five-level sequence framework is calibrated in the time domain seismic data body, that is, on the single well seismic section, to achieve the five-level sequence tracking under the control of the four-level sequence stratigraphic framework position. Figure 5 As shown, the fifth-level sequence tracing was completed on the seismic section, and the fifth-level sequence interface ①, the fifth-level sequence interface ② and the fifth-level sequence interface ③ were traced.

[0111] Embodiment 2

[0112] The embodiment of the present invention provides a layer sequence division device under the frequency division optimization of seismic data volume, referring to Figure 6 As shown, including:

[0113] Transformation module 201, used for performing wavelet transformation on the seismic data volume containing the target layer segment to obtain the seismic data volume after wavelet transformation;

[0114] A sensitive frequency range determination module 202 is used to determine the sensitive frequency range corresponding to the target layer sand body according to the seismic data body after the wavelet transformation;

[0115] The screening module 203 is used to extract multiple frequency-divided seismic data volumes within the sensitive frequency range, and screen the frequency-divided amplitude seismic data volume with the best sand body identification effect from the multiple frequency-divided seismic data volumes to obtain the target frequency-divided amplitude seismic attribute volume;

[0116] A gridding processing module 204 is used to perform three-dimensional gridding processing on the target frequency-divided amplitude seismic data volume to obtain a gridded frequency-divided amplitude seismic data volume;

[0117] An amplitude value curve establishing module 205 is used to extract the grid amplitude value of the well trajectory based on the gridded frequency-divided amplitude seismic data volume and establish an amplitude value curve;

[0118] The calibration module 206 is used to obtain a pre-established fourth-order sequence stratigraphic framework, and calibrate the fifth-order sequence stratigraphic framework position on the fourth-order sequence stratigraphic framework according to the amplitude value curve to obtain a calibrated sequence stratigraphic framework.

[0119] The implementation principle and technical effect of the device for layer division under the frequency division optimization of the seismic data volume provided in the embodiment of the present invention are similar to those of any of the aforementioned method embodiments, and will not be described in detail here.

[0120] Embodiment 3

[0121] An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the method for layer division under the frequency division optimization of the seismic data volume as described in the above method embodiment is implemented.

[0122] The computer-readable storage medium may be included in the device / apparatus described in the above embodiment; or it may exist independently without being assembled into the device / apparatus. The above computer-readable storage medium carries one or more programs, and when the above one or more programs are executed, the method according to the embodiment of the present invention is implemented.

[0123] According to an embodiment of the present invention, the computer-readable storage medium may be a non-volatile computer-readable storage medium, for example, may include but is not limited to: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, apparatus, or device.

[0124] Embodiment 4

[0125] An embodiment of the present invention provides an electronic device, referring to Figure 7 As shown, it includes a processor 111, a communication interface 112, a memory 113 and a communication bus 114, wherein the processor 111, the communication interface 112 and the memory 113 communicate with each other through the communication bus 114.

[0126] A memory 113, for storing computer programs;

[0127] The processor 111 is used to implement the layer sequence division method under the frequency division optimization of the seismic data volume as described in the above method embodiment when executing the program stored in the memory 113.

[0128] The implementation principle and technical effect of the electronic device provided by the embodiment of the present invention are similar to those of any of the aforementioned method embodiments, and will not be repeated here.

[0129] The above-mentioned memory 113 can be an electronic memory such as a flash memory, an EEPROM (electrically erasable programmable read-only memory), an EPROM, a hard disk or a ROM. The memory 113 has a storage space for program codes for executing any method steps in the above-mentioned method. For example, the storage space for program codes may include various program codes for implementing various steps in the above method respectively. These program codes can be read from or written into one or more computer program products. These computer program products include program code carriers such as hard disks, compact disks (CDs), memory cards or floppy disks. Such computer program products are usually portable or fixed storage units. The storage unit may have a storage segment or storage space arranged similarly to the memory 113 in the above-mentioned electronic device. The program code can be compressed, for example, in an appropriate form. Generally, the storage unit includes a program for executing the method steps according to an embodiment of the present invention, that is, a code that can be read by, for example, a processor 111, and when these codes are run by an electronic device, the electronic device performs the various steps in the method described above.

[0130] In this document, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. The orientation or position relationship indicated by the terms "upper", "lower", etc. is based on the orientation or position relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0131] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict. The present invention is not limited to any single aspect, any single embodiment, or any combination and / or permutation of these aspects and / or embodiments. Each aspect and / or embodiment of the present invention can be used alone, or in combination with one or more other aspects and / or other embodiments.

[0132] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for layer division under frequency division optimization of seismic data volume, characterized in that: include: Performing wavelet transformation on the seismic data volume containing the target layer segment to obtain a seismic data volume after wavelet transformation; Determine the sensitive frequency range corresponding to the target layer sand body according to the seismic data body after the wavelet transformation; Extracting a plurality of frequency-divided seismic data volumes within the sensitive frequency range, selecting a frequency-divided amplitude seismic data volume with the best sand body identification effect from the plurality of frequency-divided seismic data volumes, and obtaining a target frequency-divided amplitude seismic attribute volume; Performing three-dimensional gridding processing on the target frequency-divided amplitude seismic data volume to obtain a frequency-divided amplitude seismic data volume after gridding processing; Extracting grid amplitude values ​​of the well trajectory based on the gridded frequency-divided amplitude seismic data volume, and establishing an amplitude value curve; A pre-established fourth-order sequence stratigraphic framework is obtained, and the fifth-order sequence stratigraphic framework position is calibrated on the fourth-order sequence stratigraphic framework according to the amplitude value curve to obtain a calibrated sequence stratigraphic framework.

2. The method for layer division under the frequency division optimization of seismic data volume according to claim 1, characterized in that: The method further comprises: Under the control of the position of the fourth-level sequence stratigraphic framework, the position corresponding to the fifth-level sequence stratigraphic framework is calibrated in the time-domain seismic data volume based on the calibrated sequence stratigraphic framework to complete the fifth-level sequence tracking.

3. The method for layer sequence division under the frequency division optimization of seismic data volume according to claim 1, characterized in that: The step of performing wavelet transformation on the seismic data volume including the target layer segment to obtain the seismic data volume after wavelet transformation comprises: The seismic data volume containing the target layer is subjected to wavelet transformation by the following formula to obtain the seismic data volume after wavelet transformation: Where: WT x (a, b) represents the seismic data after wavelet transformation, a represents the scale factor; b represents the translation factor; ψ(t) represents the wavelet function; x(t) represents the seismic data.

4. The method for layer division under frequency division optimization of seismic data volume according to claim 1, characterized in that: The determining of the sensitive frequency range corresponding to the target layer sand body according to the seismic data body after the wavelet transformation comprises: Determine the velocity of the target layer sand body according to the seismic data body after the wavelet transformation; The sandstone thickness range of the target layer sand body is obtained, and the sensitive frequency range corresponding to the target layer sand body is determined by the following formula according to the sandstone thickness range and the corresponding velocity of the target layer sand body: f=V / 4*h Where: f represents the sensitive frequency, V represents the longitudinal propagation velocity of seismic waves in the target layer, and h represents the thickness of sandstone.

5. The method for layer division under frequency division optimization of seismic data volume according to claim 1, characterized in that: The amplitude seismic data volume within the sensitive frequency range is extracted in the following manner: By using the sensitive frequency corresponding to the target layer sand body, a plurality of frequency-divided seismic data volumes of a plurality of adjacent frequencies of the sensitive frequency are extracted from the wavelet transformed seismic data volume according to a preset frequency interval.

6. The method for layer sequence division under the frequency division optimization of seismic data volume according to claim 1, characterized in that: The frequency-divided amplitude seismic data volume with the best sand body identification effect is selected from the multiple frequency-divided amplitude seismic data volumes to obtain the target frequency-divided amplitude seismic attribute volume: Extracting amplitude attributes of the plurality of frequency-divided seismic data volumes, and determining a correlation coefficient between the amplitude attributes of the drilled well position and the sandstone thickness; The frequency-divided amplitude seismic data volume with the highest correlation coefficient is selected from the multiple frequency-divided amplitude seismic data volumes to obtain a target frequency-divided amplitude seismic attribute volume.

7. The method for layer division under frequency division optimization of seismic data volume according to claim 1, characterized in that: The three-dimensional gridding process is performed on the target frequency-divided amplitude seismic data volume to obtain the gridded frequency-divided amplitude seismic data volume, including: Determine the lateral accuracy of the grid based on the bins of the seismic data volume; Determine the vertical accuracy of the grid based on the average thickness of the target layer sand body; The target frequency-divided amplitude seismic data volume is subjected to three-dimensional gridding according to the determined grid transverse accuracy and grid longitudinal accuracy, and the amplitude value in the grid is assigned by the following formula to obtain the gridded frequency-divided amplitude seismic data volume: Where: G represents the geometric mean value of amplitude, X i Represents the amplitude value in the i-th grid, and n represents the number of grids.

8. The method for layer sequence division under frequency division optimization of seismic data volume according to claim 1, characterized in that: The fifth-level sequence stratigraphic framework position is calibrated on the fourth-level sequence stratigraphic framework in the following manner to obtain a calibrated sequence stratigraphic framework: According to the acquired sand body distribution characteristics and the morphological change characteristics of the amplitude value curve, the fifth-order sequence stratigraphic framework position is calibrated on the fourth-order sequence stratigraphic framework to obtain a calibrated sequence stratigraphic framework.

9. The method for layer sequence division under frequency division optimization of seismic data volume according to claim 2, characterized in that: The time domain seismic data body includes a single well seismic profile; under the control of the position of the fourth-level sequence stratigraphic framework, based on the calibrated sequence stratigraphic framework, the position corresponding to the fifth-level sequence framework is calibrated in the time domain seismic data body to complete the fifth-level sequence tracking, including: The time-depth conversion is performed on each well layer in the calibrated sequence stratigraphic framework. After the time-depth conversion, the corresponding position of the five-level sequence framework is calibrated on the single well seismic section, and the five-level sequence tracking is completed under the control of the position of the four-level sequence stratigraphic framework.

10. A device for dividing layers under frequency division optimization of seismic data volume, characterized in that: include: A transformation module, used for performing wavelet transformation on the seismic data volume containing the target layer segment to obtain the seismic data volume after wavelet transformation; A sensitive frequency range determination module is used to determine the sensitive frequency range corresponding to the target layer sand body according to the seismic data body after the wavelet transformation; A screening module is used to extract multiple frequency-divided seismic data volumes within the sensitive frequency range, and screen the frequency-divided amplitude seismic data volume with the best sand body identification effect from the multiple frequency-divided seismic data volumes to obtain the target frequency-divided amplitude seismic attribute volume; A gridding processing module, used for performing three-dimensional gridding processing on the target frequency-divided amplitude seismic data volume to obtain the frequency-divided amplitude seismic data volume after gridding processing; An amplitude value curve establishment module is used to extract the grid amplitude value of the well trajectory based on the gridded frequency-divided amplitude seismic data volume and establish an amplitude value curve; The calibration module is used to obtain a pre-established fourth-order sequence stratigraphic framework, and calibrate the fifth-order sequence stratigraphic framework position on the fourth-order sequence stratigraphic framework according to the amplitude value curve to obtain a calibrated sequence stratigraphic framework.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method for layer division under the frequency division optimization of the seismic data volume as described in any one of claims 1 to 9 is implemented.

12. An electronic device, characterized in that: It includes a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus; Memory, used to store computer programs; The processor is used to implement the layer sequence division method under the frequency division optimization of the seismic data volume as described in any one of claims 1 to 9 when executing the program stored in the memory.

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