CN113703044B

CN113703044B - Correction method and device for ancient river channel width, electronic equipment and storage medium

Info

Publication number: CN113703044B
Application number: CN202010653433.2A
Authority: CN
Inventors: 吕慧; 马灵伟; 孙振涛; 周丹
Original assignee: China Petroleum and Chemical Corp; Sinopec Geophysical Research Institute
Current assignee: China Petroleum and Chemical Corp; Sinopec Geophysical Research Institute
Priority date: 2020-05-20
Filing date: 2020-07-08
Publication date: 2024-04-09
Anticipated expiration: 2040-07-08
Also published as: CN113703044A

Abstract

The method comprises the steps of establishing a hierarchical correction model for describing the corresponding relation between the calculated width and the actual width of a seam hole body in different width ranges through forward modeling results of a plurality of seam hole body models in different widths; processing the seismic attributes of the ancient river channel to be detected by a multi-attribute superposition and fusion method to identify the form and the initial seismic abnormal boundary of the ancient river channel to be detected, thereby obtaining the initial plane spread of the ancient river channel to be detected; determining the calculated width of the ancient river channel to be measured according to the initial plane spread of the ancient river channel to be measured; and carrying out grading correction on the calculated width of the ancient river channel to be measured by using the grading correction model so as to determine the actual width of the ancient river channel to be measured. The method realizes the conversion from the geophysical attribute abnormality of the ancient river to the geological abnormality, and improves the precision of the reservoir prediction of the ancient river.

Description

Correction method and device for ancient river channel width, electronic equipment and storage medium

Technical Field

The disclosure relates to the field of petroleum geophysical exploration, in particular to a correction method and device for paleo-river width, electronic equipment and a storage medium.

Background

At present, the research on karst ancient river channels in China is mainly in northwest regions, and main research results are concentrated on a geophysical recognition method of the karst ancient river channels. The ancient river channel is identified and characterized by comprehensively utilizing the technical means such as seismic coherence attribute, three-dimensional visualization, stratum slicing, seismic frequency division, RGB mixing and the like.

The ancient river channel identification research shows that the underground river seismic characteristics are characterized in that the seismic reflection characteristics are strong reflection characteristics along the trend of the river, and the transverse continuity is good; the vertical river course is mainly beaded reflection characteristics, and relatively weak reflection which is shown by unobvious beaded characteristics of local areas exists, wherein the main river course of the hidden river has strong energy in various attribute planes and spaces, good continuity, large extension length and weak energy and poor continuity of branch river courses.

Forward simulation research shows that the change of the transverse dimension of the fracture-cavity body is positively correlated with the width of the planar spread cloth (seismic abnormal planar spread cloth) of the fracture-cavity body on the seismic section, namely, the larger the actual width of the fracture-cavity body is, the larger the width of the planar spread cloth on the seismic section is, but the corresponding relation between the two is not clear, and in particular, how to correct the width of the seismic abnormal planar spread cloth of the palaeolian river so as to improve the precision of palaeolian river reservoir prediction is a problem to be solved in the fine development and the increased storage of carbonate palaeolian river reservoirs.

Disclosure of Invention

To the above problems, the present disclosure provides a correction method, device, electronic device and storage medium for ancient river channel width, which solves the problem of difficult correction for the ancient river channel width in the prior art.

In a first aspect, the present disclosure provides a method for correcting an ancient river channel width, the method comprising:

establishing a plurality of seam-hole body models with different widths and a forward modeling observation system, wherein the forward modeling observation system is used for performing forward modeling on each seam-hole body model;

forward modeling is carried out on each fracture-cavity model through the forward modeling observation system so as to obtain the seismic profile of each fracture-cavity model;

determining the calculated width of each fracture-cavity model according to the seismic section of each fracture-cavity model, and establishing a hierarchical correction model for describing the corresponding relation between the calculated width and the actual width of the fracture-cavity body in different width ranges according to the calculated width and the actual width of all the fracture-cavity models;

acquiring post-stack seismic data of the ancient river channel to be tested, and determining the seismic attribute of the ancient river channel to be tested according to the post-stack seismic data of the ancient river channel to be tested;

processing the seismic attributes of the ancient river channel to be detected by a multi-attribute superposition and fusion method to identify the form and the initial seismic abnormal boundary of the ancient river channel to be detected, thereby obtaining the initial plane spread of the ancient river channel to be detected;

Determining the calculated width of the ancient river channel to be measured according to the initial plane spread of the ancient river channel to be measured;

and carrying out grading correction on the calculated width of the ancient river channel to be measured by using the grading correction model so as to determine the actual width of the ancient river channel to be measured.

According to an embodiment of the present disclosure, optionally, in the above correction method for ancient river channel width, according to the seismic profile of each fracture-cavity model, the calculating width of each fracture-cavity model is determined, including the following steps:

determining a distribution curve of the amplitude of each fracture-cavity model in the width direction of the fracture-cavity model according to the seismic section of each fracture-cavity model;

based on the maximum amplitude of each fracture-cavity model, respectively carrying out normalization processing on the amplitude of each fracture-cavity model to obtain a distribution curve of the normalized amplitude of each fracture-cavity model in the width direction of the fracture-cavity model;

setting a plurality of amplitude threshold values, and determining boundaries of each fracture-cavity model corresponding to the amplitude threshold values in the width direction according to distribution curves of the normalized amplitudes of each fracture-cavity model in the width direction of the fracture-cavity model;

and determining the calculated width of each fracture-cavity model corresponding to each amplitude threshold according to the boundary of each fracture-cavity model corresponding to each amplitude threshold in the width direction.

According to an embodiment of the present disclosure, optionally, in the above correction method for ancient river channel width, according to the calculated widths and actual widths of all the hole seam models, a hierarchical correction model for describing the correspondence between the calculated widths and the actual widths of the hole seam models in different width ranges is established, including the following steps:

selecting an optimal amplitude threshold value from all the amplitude threshold values according to the calculated widths and the actual widths of all the seam cavity models corresponding to all the amplitude threshold values; the optimal amplitude threshold value can enable deviation between calculated widths and actual widths of all corresponding fracture-cavity body models to be minimum;

under the optimal amplitude threshold value, performing linear fitting on the calculated widths of all the fracture-cavity models with the actual widths being larger than 1/2 of the seismic wavelet wavelength to obtain a first linear relation, and performing linear fitting on the calculated widths of all the fracture-cavity models with the actual widths being 1/4 to 1/2 of the seismic wavelet wavelength to obtain a second linear relation;

and taking the combination of the first linear relation and the second linear relation as a grading correction model for describing the corresponding relation between the calculated width and the actual width of the seam hole body in different width ranges.

According to an embodiment of the present disclosure, optionally, in the correction method for the paleo-channel width, the seismic attribute includes an amplitude attribute and a coherence attribute, wherein the amplitude attribute includes a root mean square amplitude attribute, a total energy, middle-low frequency energy and high frequency energy in a frequency division amplitude, and an amplitude average curvature; the seismic attributes of the ancient river channel to be detected are processed through a multi-attribute superposition and fusion method to identify the form and the initial seismic abnormal boundary of the ancient river channel to be detected, so that the initial plane layout of the ancient river channel to be detected is obtained, and the method comprises the following steps:

processing the middle-low frequency energy in the root mean square amplitude attribute, the total energy and the frequency division amplitude of the ancient river channel to be detected by a multi-attribute superposition and fusion method so as to identify a main river channel of the ancient river channel to be detected;

processing high-frequency energy and amplitude average curvature in frequency division amplitude of the ancient river channel to be detected by a multi-attribute superposition and fusion method so as to identify a branch river channel of the ancient river channel to be detected;

forming the form of the ancient river channel to be tested by a main river channel and a branch river channel of the ancient river channel to be tested;

processing the amplitude class attribute and the coherence attribute of the ancient river channel to be tested by a multi-attribute superposition method to determine the initial seismic anomaly boundary of the ancient river channel to be tested;

And forming initial plane spread of the ancient river channel to be tested by the form of the ancient river channel to be tested and the initial seismic abnormal boundary.

According to an embodiment of the present disclosure, optionally, in the above correction method for the width of the old river, the amplitude attribute and the coherence attribute of the old river to be measured are processed by a multi-attribute superposition method to determine an initial seismic anomaly boundary of the old river to be measured, including the following steps:

determining an initial boundary of the ancient river channel to be tested according to the coherence attribute of the ancient river channel to be tested;

and adjusting the maximum value and the minimum value of the amplitude attribute of the ancient river channel to be measured to enable the seismic anomaly boundary of the ancient river channel to be measured to coincide with the initial boundary of the ancient river channel to be measured, thereby determining the initial seismic anomaly boundary of the ancient river channel to be measured.

According to an embodiment of the present disclosure, optionally, in the above correction method for the width of the ancient river channel to be measured, the calculating width of the ancient river channel to be measured is determined according to the initial planar spread of the ancient river channel to be measured, including the following steps:

multiplying the maximum value of the amplitude class attribute of the to-be-measured old river channel corresponding to the initial plane spread of the to-be-measured old river channel by the optimal amplitude threshold value to obtain a second seismic anomaly boundary of the to-be-measured old river channel;

And determining the calculated width of the ancient river channel to be measured according to the second seismic abnormal boundary of the ancient river channel to be measured.

According to an embodiment of the present disclosure, optionally, in the above correction method for the width of the ancient river channel, the step correction is performed on the calculated width of the ancient river channel to be measured by using the step correction model, so as to determine the actual width of the ancient river channel to be measured, and the method includes the following steps:

determining the initial width of the ancient river channel to be measured according to the initial seismic abnormal boundary of the ancient river channel to be measured;

substituting the calculated width of the ancient river channel to be measured into the first linear relation when the initial width of the ancient river channel to be measured is larger than 1/2 of the wavelength of the seismic wavelet so as to correct the calculated width of the ancient river channel to be measured and calculate the actual width of the ancient river channel to be measured;

when the initial width of the ancient river channel to be measured is 1/4 of the seismic wavelet wavelength to 1/2 of the seismic wavelet wavelength, substituting the calculated width of the ancient river channel to be measured into the second linear relation so as to correct the calculated width of the ancient river channel to be measured and calculate the actual width of the ancient river channel to be measured.

In a second aspect, the present disclosure provides a correction device for ancient river channel width, the device comprising:

The system comprises a fracture-cavity model and forward modeling observation system building module, a forward modeling observation system and a model modeling module, wherein the fracture-cavity model and forward modeling observation system building module is used for building a plurality of fracture-cavity models with different widths;

the forward modeling module is used for performing forward modeling on each fracture-cavity model through the forward modeling observation system so as to obtain the seismic section of each fracture-cavity model;

the hierarchical correction model building module is used for determining the calculated width of each fracture-cavity model according to the seismic section of each fracture-cavity model, and building a hierarchical correction model for describing the corresponding relation between the calculated width and the actual width of the fracture-cavity body in different width ranges according to the calculated width and the actual width of all the fracture-cavity models;

the device comprises a to-be-measured old river channel seismic attribute determining module, a to-be-measured old river channel seismic attribute determining module and a data processing module, wherein the to-be-measured old river channel seismic attribute determining module is used for acquiring post-stack seismic data of the to-be-measured old river channel and determining the seismic attribute of the to-be-measured old river channel according to the post-stack seismic data of the to-be-measured old river channel;

the initial plane spread determining module is used for processing the seismic attributes of the ancient river channel to be detected through a multi-attribute superposition and fusion method so as to identify the form and the initial seismic abnormal boundary of the ancient river channel to be detected, thereby obtaining the initial plane spread of the ancient river channel to be detected;

The to-be-measured ancient river channel calculation width determining module is used for determining the calculation width of the to-be-measured ancient river channel according to the initial plane spread of the to-be-measured ancient river channel;

the actual width determining module of the ancient river channel to be measured is used for carrying out grading correction on the calculated width of the ancient river channel to be measured by utilizing the grading correction model so as to determine the actual width of the ancient river channel to be measured.

In a third aspect, the present disclosure provides an electronic device, including a memory and a processor, the memory having stored thereon a computer program which, when executed by the processor, performs the method of correcting the width of the culvert according to any one of the first aspects.

In a fourth aspect, the present disclosure provides a storage medium storing a computer program executable by one or more processors to implement the method for correcting a width of a paleo-river according to any one of the first aspects.

One or more embodiments of the above-described solution may have the following advantages or benefits compared to the prior art:

the method comprises the steps of establishing a hierarchical correction model for describing the corresponding relation between the calculated width and the actual width of a seam hole body in different width ranges through forward modeling results of a plurality of seam hole body models in different widths; processing the seismic attributes of the ancient river channel to be detected by a multi-attribute superposition and fusion method to identify the form and the initial seismic abnormal boundary of the ancient river channel to be detected, thereby obtaining the initial plane spread of the ancient river channel to be detected; determining the calculated width of the ancient river channel to be measured according to the initial plane spread of the ancient river channel to be measured; and carrying out grading correction on the calculated width of the ancient river channel to be measured by using the grading correction model so as to determine the actual width of the ancient river channel to be measured. According to the method, a hierarchical correction model of the paleo-river width is established based on forward modeling results of the fracture-cavity model, conversion from paleo-river geophysical attribute abnormality to geological abnormality is achieved, accuracy of paleo-river reservoir prediction is improved, reliable technical support is provided for guiding deep carbonate reservoir exploration and development efficiency, and the method has important significance for fine development and increased storage and production of carbonate paleo-river reservoirs.

Drawings

The present disclosure will be described in more detail below based on embodiments and with reference to the accompanying drawings:

fig. 1 is a flow chart of a method for correcting an ancient river channel width according to an embodiment of the present disclosure;

FIG. 2 is a schematic diagram showing a relationship between a calculated width and a real width of a series of cavity models under different amplitude thresholds according to an embodiment of the present disclosure;

FIG. 3 is a schematic diagram showing a linear relationship between calculated width and actual width of a fracture-cavity model with different width ranges obtained according to the series of fracture-cavity models according to an embodiment of the present disclosure;

fig. 4 is a schematic diagram of a width correction process of an ancient river channel to be measured according to an embodiment of the present disclosure;

FIG. 5 is a schematic diagram of a process for verifying a width correction result of a ancient river channel to be tested with a width of greater than 1/2 of a seismic wavelet wavelength according to a logging result provided in an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of a process for verifying a width correction result of a paleo-channel to be tested with a width of 1/4 to 1/2 of the seismic wavelet wavelength according to a logging result provided in an embodiment of the present disclosure;

fig. 7 is a schematic structural diagram of an ancient river channel width correction device according to an embodiment of the present disclosure;

In the drawings, like parts are given like reference numerals, and the drawings are not drawn to scale.

Detailed Description

The embodiments of the present disclosure will be described in detail below with reference to the drawings and examples, so as to solve the technical problem by applying technical means to the present disclosure, and the implementation process for achieving the corresponding technical effects can be fully understood and implemented accordingly. The embodiments of the present disclosure and various features in the embodiments may be combined with each other without conflict, and the formed technical solutions are all within the protection scope of the present disclosure.

In the following description, meanwhile, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details or in the specific manner described herein.

Example 1

Fig. 1 is a flow chart of a method for correcting an ancient river width according to an embodiment of the present disclosure, referring to fig. 1, the method for correcting an ancient river width includes:

step S101: establishing a plurality of seam-hole body models with different widths and a forward modeling observation system, wherein the forward modeling observation system is used for performing forward modeling on each seam-hole body model;

Specifically, the establishment of the seam hole body models with different widths mainly comprises the steps of setting the shape and the size (mainly the transverse dimension, namely the width) of the seam hole body models, the transverse interval between the seam hole bodies, the filling speed in the seam hole bodies and the background surrounding rock speed.

It should be noted that, only one hole body is provided in each hole body model, so as to eliminate mutual interference between the hole bodies.

Specifically, the forward modeling observation system is mainly established by setting the offset, the track spacing, the maximum full coverage times and the excitation wavelet main frequency of the forward modeling observation system. The forward simulation observation system is established by referring to an actual observation system, actual seismic data are acquired with specific observation system parameters, such as gun spacing, channel spacing, arrangement length and the like, in order to enable the subsequent forward simulation result to be guided and applied to the actual data, the forward simulation needs to be performed by adopting the same observation system as the actual observation system, and in the embodiment, key parameters of the forward simulation observation system can be set as follows: the channel spacing is 50m, the gun spacing is 50m, the primary wavelet frequency is 30Hz, the maximum number of times of full coverage is 40, and the primary wavelet frequency is excited by 30Hz Rake wavelet.

The seismic wave propagation numerical simulation technology is an effective way for researching the seismic wave rule, and the forward simulation observation system can effectively collect, process and explain the seismic data.

Step S102: and performing forward modeling on each fracture-cavity model through the forward modeling observation system to obtain the seismic profile of each fracture-cavity model.

Specifically, step S102 includes the steps of:

s102a: carrying out wave equation forward modeling on each fracture-cavity body model by using the forward modeling observation system by using Rake wavelets so as to obtain a shot set record of each fracture-cavity body model;

s102b: processing shot set records of each fracture-cavity body model by adopting a Ke Xihuo f prestack depth migration imaging method to obtain prestack depth domain migration sections of each fracture-cavity body model;

s102c: and performing time-depth conversion on the pre-stack depth domain migration profile of each fracture-cavity model to obtain the pre-stack time domain migration profile of each fracture-cavity model.

Specifically, the wave equation forward modeling is carried out on each fracture-cavity body model by using the Rake wavelet with the main frequency of 30Hz, the seismic forward modeling is simplified modeling by using the basic theory of the researched geological problem, and the geological problem is solved by using a numerical simulation method in addition to the constraint condition of the seismic forward modeling, so that the relevant seismic wave field synthesis record is obtained, and the method is an effective means for understanding the propagation characteristics of the seismic wave in the underground medium and helping to explain and observe geological data. Seismic forward modeling is a process of finding measured data, known as geologic models. The whole process of the earthquake forward modeling is as follows:

(a) Establishing a geological model (namely a fracture-cavity model in the embodiment);

(b) The rock information is converted into seismic wave information (i.e., the step of obtaining shot gather records in this embodiment);

(c) Seismic wave field synthesis record (i.e. the step of processing shot gather record by adopting Ke Xihuo f prestack depth migration imaging technology in the embodiment)

Seismic forward modeling is an important technical means for studying the propagation characteristics of seismic waves. The method can directly guide the acquisition, processing and interpretation of actual data through the forward simulation of the earthquake, can also provide theoretical data for the research of inversion, and can evaluate the effectiveness of inversion results. Geologist utilizes forward modeling of earthquake to help explain observed earthquake data, test new algorithm and processing requirements, provide thinking for inversion, strengthen deep research and understanding of earthquake wave propagation rule, help understanding and solve new problems in current earthquake exploration and development.

The forward modeling method has various methods, wherein the forward modeling based on wave equation can well reflect the propagation rule of the seismic wave in the complex underground medium, so that people can conveniently study the propagation condition of the seismic wave in the complex underground medium, and the forward modeling method is frequently used in the forward modeling of the seismic wave.

And proper selection of the seismic wavelet is the key to wave equation based forward modeling of the seismic. The actual reception of a seismic wavelet requires a series of procedures: firstly, the excitation of the earthquake wave, then the propagation of the earthquake wave and finally the receiving of the earthquake wave are carried out, and the series of processes are equivalent to a geodetic filtering system. The seismic wavelet is an aperiodic vibration signal with a certain duration. So the proper seismic wavelet is selected to determine the coincidence degree of the forward result and the actual result.

In seismic exploration, seismic wavelets tend to have uncertainty. On land, the waveform of the seismic waves may vary greatly from the surface, and the source may produce ghosts, etc., because the recording system is a component that has no direction-finding changes. In the ocean, it is often assumed that the source and depth remain unchanged and that only the propagation effects can be changed, so that seismic exploration in many areas of the sea requires compensation and depth stacking, otherwise the exploration results are likely to be ineffective. The resolution of the seismic waves affects the resolution of the final synthetic seismic record and has a very important influence on the exploration results, so that the selection of the seismic wavelets is very important. In the actual exploration process, the common seismic wavelets include Shi wavelets, sine exponential decay wavelets, rake wavelets and the like.

In this embodiment, the seismic wavelet is a Rake wavelet.

The Ricker wavelet is a zero-phase wavelet, which is a common basic seismic wavelet proposed by Norman Ricker at 1940 and widely used for making synthetic seismic records, and the waveform of the Ricker wavelet is relatively simple and symmetrical, with a strong peak in the middle and weak side lobes on both sides. The video dominant frequency or dominant frequency of the Rake wavelet may be represented by the inverse 1/T of the time T between the two side lobes.

The characteristics of displacement, velocity, acceleration form and the like of particle motion of the Rake wavelet are very similar to those of actual seismic wavelets on the premise of not considering the accuracy of the instrument, and a great number of experiments prove that the synthetic seismic record by using the Rake wavelet can have a very good matching degree with the actual seismic record, so the method is generally considered to be a representation of ideal field seismic wavelets and is further used for interpretation and calculation of a seismic model. With respect to the discussion of the attenuation of the sub-waves, the seismic wavelets are mathematically, so that the state of the wavelets and the mechanism of waveform change can be better understood, and the design and experiment of the model can be facilitated.

In the forward modeling process, a Rake wavelet is transmitted to the fracture-cavity model, when the Rake wavelet propagates underground and encounters a wave impedance interface (generally the interface of two strata), reflection occurs, and then the reflection signals are recorded at different positions on the ground by a precise instrument, so that an earthquake shot set record is obtained. Continuously exciting and receiving at different positions to obtain a series of shot set records.

And then performing horizontal superposition and offset imaging on the shot set record by a Ke Xihuo f prestack depth offset imaging method to obtain a prestack depth domain offset section.

The principle of Ke Xihuo f prestack depth migration imaging method is as follows: in the depth domain shift algorithm of various wave equations, each calculation method has its own characteristics, and the relative accuracy of solutions and the running time of a computer are also affected differently. Ke Xihuo f prestack depth migration imaging can be applied to high angle oblique layers and severe lateral velocity variations. And meanwhile, the refraction effect of the curved interface and the strong refraction surface of the medium on the seismic wave rays is well estimated. The three-dimensional depth domain offset calculation formula under the layered medium model is as follows:

Wherein x and y are horizontal coordinates, and z is depth; t is the offset field at point (x ₁ ,y ₁ ,z ₁ ) When traveling on the two-way travel; r is (x) ₁ ,y ₁ ,z ₁ ) The distance between points to (x, y, z=0); theta is z-axis and link (x ₁ ,y ₁ ,z ₁ ) Straight line of point and (x, y, z=0) pointAn included angle between the two; k is a constant; v is the velocity of propagation of the seismic wave. The above equation can ultimately be attributed to the sum of the seismic wavefields observed from the diffraction-controlled time-distance curve for a given aperture.

It is assumed in the depth domain that a point (x, y, z) is an output point of this reflection point. In order to obtain a reflection output at the point a considerable number of input tracks need to be input around the point (x, y, z), the reflection passing through the point going through different paths to different detectors. The travel time from the source back to the detector via the reflection point is equal to the travel time from the source back to the detector via the reflection point plus the travel time from the reflection point to the detector, so to acquire the image after the reflection point is offset, we first calculate the travel time, then offset the input trace amplitude to the position of the output depth trace according to this time, all input traces repeat this process, and finally add up the amplitudes of the depth traces. If it is a strong reflection point and the speed is correct, the amplitudes are superimposed in phase and reinforce each other to obtain a strong energy output with good focusing, otherwise, they cancel each other to obtain a weak amplitude output.

The Ke Xihuo f prestack depth migration imaging method mainly comprises the following steps: initial model calculation, travel time calculation, ke Xihuo f offset summation, and depth velocity model correction.

Ke Xihuo f prestack depth migration imaging overcomes the difficulty that seismic data are low in superposition times and small in migration distance range, and an accurate depth-speed model is difficult to obtain, and an ideal depth migration data body is obtained.

And then, performing time-depth conversion on the prestack depth domain migration profile, and converting the depth domain into a time domain to obtain a prestack time domain migration profile commonly used in analysis in the prior art.

It should be noted that in the prestack time domain migration profile, each cavity body model appears as a "beaded" reflection feature. From the "beaded" reflection characteristics, the distribution of the amplitude of each cavity body model across the width of the cavity body model can be determined.

Step S103: according to the seismic sections of the various fracture-cavity models, the calculated widths of the various fracture-cavity models are determined, and according to the calculated widths and the actual widths of all the fracture-cavity models, a hierarchical correction model for describing the corresponding relation between the calculated widths and the actual widths of the fracture-cavity models in different width ranges is established.

Specifically, step S103 includes the steps of:

s103a: determining a distribution curve of the amplitude of each fracture-cavity model in the width direction of the fracture-cavity model according to the seismic section of each fracture-cavity model;

s103b: based on the maximum amplitude of each fracture-cavity model, respectively carrying out normalization processing on the amplitude of each fracture-cavity model to obtain a distribution curve of the normalized amplitude of each fracture-cavity model in the width direction of the fracture-cavity model;

s103c: setting a plurality of amplitude threshold values, and determining boundaries of each fracture-cavity model corresponding to the amplitude threshold values in the width direction according to distribution curves of the normalized amplitudes of each fracture-cavity model in the width direction of the fracture-cavity model;

s103d: and determining the calculated width of each fracture-cavity model corresponding to each amplitude threshold according to the boundary of each fracture-cavity model corresponding to each amplitude threshold in the width direction.

S103e: selecting an optimal amplitude threshold value from all the amplitude threshold values according to the calculated widths and the actual widths of all the seam cavity models corresponding to all the amplitude threshold values; the optimal amplitude threshold value can enable the calculated widths of all the corresponding fracture-cavity body models to be closest to the deviation between the calculated widths and the actual widths to be the smallest;

S103f: under the optimal amplitude threshold value, performing linear fitting on the calculated widths of all the fracture-cavity models with the actual widths being larger than 1/2 of the seismic wavelet wavelength to obtain a first linear relation, and performing linear fitting on the calculated widths of all the fracture-cavity models with the actual widths being 1/4 to 1/2 of the seismic wavelet wavelength to obtain a second linear relation;

s103g: and taking the combination of the first linear relation and the second linear relation as a grading correction model for describing the corresponding relation between the calculated width and the actual width of the seam hole body in different width ranges.

Specifically, each fracture-cavity model is discretized into the integration of point scatterers, and the amplitudes of points at different positions are counted, so that a distribution curve of the amplitudes of each fracture-cavity model in the width direction of the fracture-cavity model can be obtained, the amplitude of the fracture-cavity model is maximum at the center position, and the amplitude is smaller as the amplitude is closer to the boundary.

The amplitudes of the fracture-cavity body models are processed through maximum amplitude normalization, after the processing, the amplitude of the central position becomes 1, and the amplitudes of the two sides are smaller than 1 and are closer to the boundary, and the numerical value is smaller.

It should be noted that, typically, 40%, 50%, 60%, 70%, 80% are selected as the amplitude threshold values, wherein the amplitude threshold values are percentages because the amplitude has been normalized. The horizontal line corresponding to each amplitude threshold value and the distribution curve of the normalized amplitude of each fracture-cavity body model in the width direction of the fracture-cavity body model have two intersection points, the two intersection points respectively correspond to the boundary of the fracture-cavity body model in the width direction, and the difference value of the abscissa coordinates of the two intersection points is the calculated width corresponding to each amplitude threshold value.

And selecting an amplitude threshold value with the smallest deviation from the amplitude threshold values as an optimal amplitude threshold value according to the deviation between the calculated widths and the actual widths of all the seam cavity models corresponding to the amplitude threshold values.

The method comprises the steps of comparing a relation curve of calculated widths and actual widths of all the fracture-cavity body models corresponding to all the amplitude threshold values with a relation curve when the calculated widths and the actual widths completely coincide (in an ideal case), wherein the amplitude threshold value of the relation curve closest to the ideal case is the optimal amplitude threshold value.

When the actual width of the hole is smaller than a certain width and gradually decreases, the error between the calculated width and the actual width gradually increases, the width is the minimum width (minimum width without calibration) without correction, and the width is 1/4 of the wavelength (1/4 lambda) of the seismic wavelet.

Because the actual width is greater than the slit cavity model of 1/2 of the wavelet wavelength (greater than 1/2 lambda) and the actual width is between 1/4 of the wavelet wavelength and 1/2 of the wavelet wavelength (1/4 lambda-1/2 lambda), the slope of the relation curve between the calculated width and the actual width is different, the slit cavity models in the two width ranges are separately fitted, and two linear relations are respectively obtained. This allows for a graduated correction of the reservoir width.

Step S104: and acquiring post-stack seismic data of the ancient river channel to be tested, and determining the seismic attribute of the ancient river channel to be tested according to the post-stack seismic data of the ancient river channel to be tested.

Specifically, the ancient river channel to be detected is explored by manually exciting seismic waves, so that post-stack seismic data of the ancient river channel to be detected are obtained.

Seismic exploration is an exploration tool that is performed by manually exciting seismic waves, using a specific observation system to receive reflected waves from a reflective interface, and seismic data processing is the second stage of seismic exploration. It is critical that the acquisition system and the original seismic gather be known before processing work can be done. By analyzing the seismic data in detail, the characteristics of the seismic data are defined, and the processing flow suitable for the data can be formulated in a targeted manner.

Seismic attribute is a measure of the geometric, kinematic, dynamic and statistical characteristics of seismic data. At present, attribute parameters extracted from seismic data are basically classified into 6 major categories, namely, kinematic characteristic parameters, dynamic characteristic parameters, morphological characteristic parameters, elastic parameters, viscosity parameters and geological parameters, wherein the kinematic and dynamic characteristic parameters are commonly used for seismic attribute technology. Common seismic attributes are mainly amplitude, waveform, frequency, attenuation factor, velocity, phase, correlation coefficient, energy and ratio, etc. The sensitivity degree of different seismic attributes to different geological attributes is different, the law is required to be searched in continuous practical exploration aiming at the seismic attribute identification of the karst palace river channel, the seismic attributes which are more sensitive to the karst palace river channel with different geological features are summarized, and then optimization, combination and fusion are carried out, so that the comprehensive depiction of the karst palace river channel is further carried out.

In this embodiment, the seismic attributes include an amplitude class attribute and a coherence attribute, wherein the amplitude class attribute includes a root mean square amplitude attribute, a total energy, mid-low frequency energy and high frequency energy in a divided amplitude, and an amplitude average curvature.

Step S105: and processing the seismic attributes of the ancient river channel to be detected by a multi-attribute superposition and fusion method to identify the form and the initial seismic abnormal boundary of the ancient river channel to be detected, thereby obtaining the initial plane spread of the ancient river channel to be detected.

Specifically, step S105 includes the steps of:

s105a: processing the root mean square amplitude attribute, the total energy and the middle-low frequency energy attribute in the frequency division amplitude of the ancient river channel to be detected by a multi-attribute superposition and fusion method so as to identify a main river channel of the ancient river channel to be detected;

s105b: processing high-frequency energy and amplitude average curvature attribute in frequency division amplitude of the ancient river channel to be detected by a multi-attribute superposition and fusion method so as to identify a branch river channel of the ancient river channel to be detected;

s105c: the form of the to-be-measured ancient river channel is formed by a main river channel of the to-be-measured ancient river channel and branch river channels of the to-be-measured ancient river channel;

S105d: processing the amplitude class attribute and the coherence attribute of the ancient river channel to be detected by a multi-attribute superposition method, and identifying an initial seismic anomaly boundary of the ancient river channel to be detected;

s105e: and forming initial plane spread of the ancient river channel to be tested by the form of the ancient river channel to be tested and the initial seismic abnormal boundary.

Firstly, carrying out attribute optimization on the identification of a main river and a branch river of the ancient river to be tested, and determining the dominant attributes of the main river and the branch river.

The dominant attributes of the main river channel are root mean square amplitude attribute, total energy and middle and low frequency energy of the frequency division amplitude, and the dominant attributes of the branch river channel are high frequency energy of the frequency division amplitude and amplitude average curvature. Therefore, different attributes have different recognition effects on different levels of ancient river channels.

Therefore, based on the dominant properties of the main river channel and the branch river channel, the overall distribution state of the river channel can be clearly and intuitively recognized through the superposition and fusion technology of various property methods. Therefore, the main river channel of the ancient river channel to be detected can be identified by processing the root mean square amplitude attribute, the total energy and the middle-low frequency energy attribute in the frequency division amplitude of the ancient river channel to be detected through a multi-attribute superposition and fusion method. Similarly, the branch river of the ancient river to be detected can be identified by processing the high-frequency energy and the average curvature attribute of the amplitude in the frequency division amplitude of the ancient river to be detected through a multi-attribute superposition and fusion method.

Wherein, the step S105d for initial seismic anomaly boundary identification includes the steps of:

(a) Determining an initial boundary of the ancient river channel to be tested according to the coherence attribute of the ancient river channel to be tested;

(b) And adjusting the maximum value and the minimum value of the amplitude attribute of the ancient river channel to be measured to enable the seismic anomaly boundary of the ancient river channel to be measured to coincide with the initial boundary of the ancient river channel to be measured, thereby determining the initial seismic anomaly boundary of the ancient river channel to be measured.

Because the range of values for each seismic attribute is different, the color scale may change by adjusting the size of the maximum and minimum ranges. The coherence attribute belongs to a geometric attribute, which determines that the seismic anomaly boundary of the river channel is fixed, and adjusting the coherence attribute threshold does not change the identification of the boundary (i.e., width) of the river channel; amplitude class attributes adjust the maximum and minimum values, and the channel width represented by the amplitude changes. And adjusting the maximum value and the minimum value of the amplitude attribute to enable the energy abnormality to be filled in the river boundary determined by the coherence attribute, namely enabling the energy (amplitude) abnormality boundary to coincide with the initial boundary of the ancient river to be measured. The method realizes the identification of the initial seismic anomaly boundary of the old river by overlapping two attributes (amplitude attribute and coherence attribute).

In this step, according to the recognition result of the abnormal boundary of the initial earthquake of the ancient river channel to be measured, the abnormal width (initial width) of the initial earthquake of the ancient river channel to be measured is defined, and a foundation is laid for the next step of the hierarchical correction of the width of the ancient river channel to be measured.

Step S106: and determining the calculated width of the to-be-measured ancient river channel according to the plane spread of the to-be-measured ancient river channel.

Specifically, step S106 includes the steps of:

s106a: multiplying the maximum value of the amplitude class attribute of the to-be-measured old river channel corresponding to the initial plane spread of the to-be-measured old river channel by the optimal amplitude threshold value to obtain a second seismic anomaly boundary of the to-be-measured old river channel;

s106b: and determining the calculated width of the ancient river channel to be measured according to the second seismic abnormal boundary of the ancient river channel to be measured.

Namely, when the seismic anomaly boundary of the to-be-measured old river channel coincides with the initial boundary of the to-be-measured old river channel, the maximum value of the amplitude attribute of the to-be-measured old river channel is multiplied by the optimal amplitude threshold value, and the seismic anomaly boundary shown by the to-be-measured old river channel changes, so that the second seismic anomaly boundary of the to-be-measured old river channel can be obtained. And determining the width (calculated width) corresponding to the second seismic abnormal boundary by measuring the point moment according to the second seismic abnormal boundary of the ancient river channel to be measured.

In addition, the step of determining the calculated width of the ancient river channel to be measured can also refer to the step of determining the calculated width of the fracture-cavity model, and the corresponding steps are as follows:

(a) Determining a distribution curve of the amplitude of the to-be-measured old river in the width direction of the to-be-measured old river according to the initial plane spread of the to-be-measured old river;

(b) Based on the maximum amplitude of the to-be-measured old river, carrying out normalization processing on the amplitude of the to-be-measured old river to obtain a distribution curve of the normalized amplitude of the to-be-measured old river in the width direction of the to-be-measured old river;

(c) Determining the boundary of the to-be-measured ancient river channel in the width direction from the distribution curve of the normalized amplitude of the to-be-measured ancient river channel in the width direction according to the optimal amplitude threshold value;

(d) And determining the calculated width of the to-be-measured ancient river channel according to the boundary of the to-be-measured ancient river channel in the width direction.

The plane spread of the ancient river channel to be measured is obtained by processing the seismic attributes of the ancient river channel to be measured through a multi-attribute superposition and fusion method, so that the distribution curve of the amplitude of the ancient river channel to be measured in the width direction of the ancient river channel to be measured can be directly obtained from the plane spread of the ancient river channel to be measured. Then, the method for determining the calculated width of the ancient river channel to be measured is the same as that in step 103, and is firstly normalization processing, and then, the boundary is determined according to the optimal threshold value, so that the calculated width is determined.

Step S107: and carrying out grading correction on the calculated width of the ancient river channel to be measured by using the grading correction model so as to determine the actual width of the ancient river channel to be measured.

Specifically, step S107 includes the steps of:

step S107a: determining the initial width of the ancient river channel to be measured according to the initial seismic abnormal boundary of the ancient river channel to be measured;

step S107b: substituting the calculated width of the ancient river channel to be measured into the first linear relation when the initial width of the ancient river channel to be measured is larger than 1/2 of the wavelength of the seismic wavelet so as to correct the calculated width of the ancient river channel to be measured and calculate the actual width of the ancient river channel to be measured;

step S107c: when the initial width of the ancient river channel to be measured is 1/4 of the seismic wavelet wavelength to 1/2 of the seismic wavelet wavelength, substituting the calculated width of the ancient river channel to be measured into the second linear relation so as to correct the calculated width of the ancient river channel to be measured and calculate the actual width of the ancient river channel to be measured.

The corresponding linear relation is selected to have a certain error through calculating the width, so that the corresponding linear relation can be more accurately selected through the initial width (namely the transverse width of the seismic amplitude energy) obtained according to the seismic anomaly boundary of the ancient river channel to be detected.

Moreover, since the lateral width is smaller than 1/4 wavelength for the old river with seismic amplitude energy, it is difficult to quantitatively correct the result. Therefore, the embodiment is only suitable for ancient river channels with the transverse width of the earthquake amplitude energy being larger than 1/4 wavelength.

The correction method for the ancient river channel width comprises the steps of establishing a hierarchical correction model for describing the corresponding relation between the calculated width and the actual width of the seam hole body in different width ranges through forward modeling results of a plurality of seam hole body models in different widths; processing the seismic attributes of the ancient river channel to be detected by a multi-attribute superposition and fusion method to identify the form and the initial seismic abnormal boundary of the ancient river channel to be detected, thereby obtaining the initial plane spread of the ancient river channel to be detected; determining the calculated width of the ancient river channel to be measured according to the initial plane spread of the ancient river channel to be measured; and carrying out grading correction on the calculated width of the ancient river channel to be measured by using the grading correction model so as to determine the actual width of the ancient river channel to be measured. According to the method, a hierarchical correction model of the paleo-river width is established based on forward modeling results of the fracture-cavity model, conversion from paleo-river geophysical attribute abnormality to geological abnormality is achieved, accuracy of paleo-river reservoir prediction is improved, reliable technical support is provided for guiding deep carbonate reservoir exploration and development efficiency, and the method has important significance for fine development and increased storage and upper production of carbonate paleo-river reservoirs.

Example two

On the basis of embodiment one, this embodiment will explain the method described in embodiment one by way of specific application cases.

In the embodiment, a series of seam hole body models with different widths are established, and the irregularity of the seam hole shape and the filling characteristic change are considered. The filling speed of the fracture-cavity body is 4800m/s, and the background surrounding rock is 6000m/s. And taking hundreds of forward modeling results of the fracture-cavity as quantitative analysis samples, and carrying out quantitative characterization of the fracture-cavity body.

The numerical simulation of the heterogeneous medium wave equation is adopted, and main parameters of a forward simulation observation system are as follows: the offset is 50m, the track interval is 50m, the maximum full coverage times are 40 times, and the main frequency of the excitation wavelet adopts 30Hz Rake wavelet.

And performing forward modeling on each fracture-cavity model through the forward modeling observation system to obtain the seismic profile of each fracture-cavity model. Based on forward modeling results, extracting distribution curves of amplitudes corresponding to each fracture-cavity model in the width direction of the fracture-cavity model; based on the maximum amplitude of each fracture-cavity model, normalizing the amplitude corresponding to each fracture-cavity model to obtain a distribution curve of the amplitude of each normalized fracture-cavity model in the width direction of the fracture-cavity model.

And respectively taking 40%, 50%, 60%, 70% and 80% of the amplitude threshold values as amplitude threshold values, determining the boundary of each fracture-cavity body model corresponding to each amplitude threshold value in the width direction according to the normalized amplitude distribution curve, and further determining the calculated width of each fracture-cavity body model corresponding to each amplitude threshold value.

The relationship between the calculated width and the actual width when different amplitude threshold values are counted, and when the amplitude threshold values are 40%, 50%, 60%, 70%, 80% respectively, as shown in fig. 2, the relationship between the calculated width and the actual width is counted, and the diagonal line in the figure is a relationship curve (ideal relationship curve) when the calculated width and the actual width completely coincide. As can be seen from the figure, when the amplitude threshold value is 60%, the relationship between the corresponding calculated width and the actual width is closest to the ideal relationship curve, so the deviation of the calculated width obtained by the amplitude threshold value of 60% is the smallest, so in this embodiment, 60% is selected as the optimal amplitude threshold value, and the reliability of the correction can be ensured. Moreover, as can be seen from the figure, the relation between the calculated width and the actual width is different in different actual width ranges, and the relation is mainly represented by three width ranges of the actual width being smaller than 1/4 of the seismic wavelet wavelength (smaller than 50 m), the actual width being between 1/4 and 1/2 of the seismic wavelet wavelength (50 to 100 m) and the actual width being larger than 1/2 of the seismic wavelet wavelength (larger than 100 m).

The calculated widths and the actual widths of the hole body models in the three width ranges are respectively fitted under the optimal amplitude threshold value (60%), and the fitting result is shown in fig. 3, so that the following can be seen:

when the actual width is smaller than 1/4 of the wave length of the earthquake wavelet (smaller than 50 m), the obtained linear relation is y=0.1421x+48, the slope is small, the intercept is large, and the calculated width is almost consistent no matter what the marginal width of the fracture-cavity model is, so the width of the fracture-cavity model in the range can not be corrected;

when the actual width is between 1/4 and 1/2 of the wavelength of the seismic wavelet (50-100 m), the obtained linear relationship is y=0.94x+2.7 (second linear relationship), and the linear relationship correlation coefficient R ² Up to 0.99, the calculated width is almost identical to the actual width, but slightly different;

when the actual width is larger than 1/2 of the wavelength of the seismic wavelet (larger than 100 m), the obtained linear relation is y= 0.9992x-1.9051 (first linear relation), and the linear relation correlation coefficient R ² The calculated width is very consistent with the actual width up to 0.9999, and the relation between the calculated width and the actual width is coincident with an ideal relation curve, so that the calculated width can be directly used as the actual width without correcting the width of the fracture-cavity model in the range.

The combination of the first linear relationship and the second linear relationship is used as a hierarchical correction model for describing the correspondence between the calculated width and the actual width of the hole body in different width ranges in the embodiment.

Next, post-stack seismic data of the paleo-channel to be measured are obtained, the seismic attributes of the paleo-channel to be measured are determined according to the post-stack seismic data of the paleo-channel to be measured, and the seismic attributes of the paleo-channel to be measured are processed through a multi-attribute superposition and fusion method to identify the morphology and the initial seismic abnormal boundary of the paleo-channel to be measured, so that the initial plane spread of the paleo-channel to be measured is obtained.

Multiplying the maximum value of the amplitude attribute of the to-be-measured old river channel corresponding to the superposition of the seismic anomaly boundary of the to-be-measured old river channel and the initial boundary of the to-be-measured old river channel by the optimal amplitude threshold value according to the obtained initial plane spread of the to-be-measured old river channel to obtain a second seismic anomaly boundary of the to-be-measured old river channel; according to the second seismic anomaly boundary of the ancient river channel to be measured, the calculation width of the ancient river channel to be measured is determined, and of course, a plurality of calculation widths can be obtained for different positions of the ancient river channel to be measured due to the fact that the length of the ancient river channel to be measured is longer.

Then determining the initial width of the ancient river channel to be measured according to the initial seismic anomaly boundary of the ancient river channel to be measured, and selecting a corresponding linear relation for correcting the initial width of different positions of the ancient river channel to be measured:

when the initial width of the ancient river channel to be measured is greater than 1/2 of the seismic wavelet wavelength (greater than 100 m), substituting the calculated width of the ancient river channel to be measured into a first linear relation (y= 0.9992 x-1.9051) to correct the calculated width of the ancient river channel to be measured and calculate the actual width of the ancient river channel to be measured. That is, for the width of this range, the calculated width may be directly used as the actual width without correction, approximately;

when the initial width of the ancient river channel to be measured is 1/4 of the wavelet wavelength to 1/2 of the wavelet wavelength (50-100 m), substituting the calculated width of the ancient river channel to be measured into the second linear relation (y=0.94x+2.7) so as to correct the calculated width of the ancient river channel to be measured and calculate the actual width of the ancient river channel to be measured.

After the widths of different positions of the ancient river channels to be measured are corrected, final plane spread is obtained, as shown in fig. 4, the point distance is 60m, and after correction, the width of the narrowest part of the two ancient river channels in the figure is about 25m, and the width of the widest part is about 180 m.

In order to verify the grading correction model, the correction results of the ancient river channels with different widths can be verified through the horizontal well penetrating through the river channel.

For example, as shown in fig. 5, the width of the ancient river to be measured is greater than 100m, and the horizontal well a logging of the inclined river shows that the river width is 145m (actual width). At this position, the width (initial width) of the old river determined based on the initial seismic anomaly boundary is 180m, the calculated width obtained after processing by the amplitude threshold value of 60% is 140m (greater than 100m, the calculated width is approximate to the actual width, the calculated width is the actual width), and the degree of coincidence with the actual width 145m of the river explained by the A logging is high.

As shown in fig. 6, the width of the ancient river channel to be measured is 50-100 m, the horizontal well B logging of the inclined through river channel shows that the width of the river channel is 60m, and at this position, the actual width of the corrected river channel is 70m, which is basically consistent with the actual width of the river channel 60m explained by the B logging.

Therefore, the above-described built hierarchical correction model is effective.

The forward modeling and well drilling verification analysis show that the prediction (correction) precision of the ancient river channel with the width of more than 100m reaches more than 90 percent; for ancient river channels with the width of 50-100 m, the prediction (correction) precision is about 80%. The ancient river course less than 50m, the quantization reliability is lower, can't quantify, do not consider the correction of the ancient river course less than 50m in this embodiment.

Example III

Fig. 7 is a schematic structural diagram of a correction device for ancient river channel width provided in an embodiment of the present disclosure, please refer to fig. 7, and the embodiment provides a correction device 100 for ancient river channel width, which includes a fracture-cavity model and forward modeling observation system building module 101, a forward modeling module 102, a hierarchical correction model building module 103, a seismic attribute determining module 104 for ancient river channel to be measured, an initial plane spread determining module 105 for ancient river channel to be measured, a calculation width determining module 106 for ancient river channel to be measured, and an actual width determining module 107 for ancient river channel to be measured.

The system comprises a fracture-cavity model and forward modeling observation system establishing module 101, a forward modeling observation system and a model analysis module, wherein the fracture-cavity model and forward modeling observation system establishing module is used for establishing a plurality of fracture-cavity models with different widths and forward modeling observation systems, and the forward modeling observation systems are used for performing forward modeling on each fracture-cavity model;

the forward modeling module 102 is configured to perform forward modeling on each fracture-cavity model through the forward modeling observation system, so as to obtain a seismic section of each fracture-cavity model;

the hierarchical correction model building module 103 is used for determining the calculated width of each fracture-cavity model according to the seismic section of each fracture-cavity model, and building a hierarchical correction model for describing the corresponding relation between the calculated width and the actual width of the fracture-cavity body in different width ranges according to the calculated width and the actual width of all the fracture-cavity models;

The to-be-measured old river seismic attribute determining module 104 is configured to obtain post-stack seismic data of the to-be-measured old river, and determine a seismic attribute of the to-be-measured old river according to the post-stack seismic data of the to-be-measured old river;

the initial plane spread determining module 105 is configured to process the seismic attribute of the old river to be measured by a multi-attribute superposition and fusion method, so as to identify the form and the initial seismic abnormal boundary of the old river to be measured, thereby obtaining the initial plane spread of the old river to be measured;

the to-be-measured ancient river channel calculation width determining module 106 is configured to determine a calculation width of the to-be-measured ancient river channel according to an initial plane spread of the to-be-measured ancient river channel;

the actual width determining module 107 of the ancient river channel to be measured is configured to perform hierarchical correction on the calculated width of the ancient river channel to be measured by using the hierarchical correction model, so as to determine the actual width of the ancient river channel to be measured.

The method comprises the steps that a fracture-cavity model and forward simulation observation system building module 101 builds a plurality of fracture-cavity models with different widths and forward simulation observation systems, and a forward simulation module 102 performs forward simulation on each fracture-cavity model through the forward simulation observation systems so as to obtain seismic profiles of each fracture-cavity model; the hierarchical correction model building module 103 determines the calculated width of each fracture-cavity model according to the seismic section of each fracture-cavity model, and builds a hierarchical correction model for describing the corresponding relation between the calculated width and the actual width of the fracture-cavity body in different width ranges according to the calculated width and the actual width of all the fracture-cavity models; the to-be-measured old river seismic attribute determining module 104 obtains post-stack seismic data of the to-be-measured old river and determines the seismic attribute of the to-be-measured old river according to the post-stack seismic data of the to-be-measured old river; the initial plane spread determining module 105 of the ancient river channel to be measured processes the seismic attribute of the ancient river channel to be measured through a multi-attribute superposition and fusion method so as to identify the form and the initial seismic abnormal boundary of the ancient river channel to be measured, thereby obtaining the initial plane spread of the ancient river channel to be measured; the to-be-measured old river calculation width determining module 106 determines the calculation width of the to-be-measured old river according to the initial plane spread of the to-be-measured old river; the actual width determining module 107 of the ancient river channel to be measured uses the grading correction model to perform grading correction on the calculated width of the ancient river channel to be measured, so as to determine the actual width of the ancient river channel to be measured.

The specific embodiment of the method for performing the correction of the ancient river channel width based on the above modules is described in detail in the first embodiment, and will not be repeated here.

Example IV

The embodiment of the application provides electronic equipment which can be a mobile phone, a computer or a tablet personal computer and the like, and comprises a memory and a processor, wherein a computer program is stored in the memory, and the computer program realizes the correction method of the width of the ancient river channel as described in the first embodiment when being executed by the processor. It is to be appreciated that the electronic device can also include an input/output (I/O) interface, as well as a communication component.

The processor is configured to execute all or part of the steps in the correction method for the ancient river channel width as in the first embodiment. The memory is used to store various types of data, which may include, for example, instructions for any application or method in the electronic device, as well as application-related data.

The processor may be an application specific integrated circuit (Application Specific Integrated Circuit, abbreviated as ASIC), a digital signal processor (Digital Signal Processor, abbreviated as DSP), a digital signal processing device (Digital Signal Processing Device, abbreviated as DSPD), a programmable logic device (Programmable Logic Device, abbreviated as PLD), a field programmable gate array (Field Programmable Gate Array, abbreviated as FPGA), a controller, a microcontroller, a microprocessor, or other electronic components for executing the correction method of the paleo river width in the first embodiment.

The Memory may be implemented by any type of volatile or non-volatile Memory device or combination thereof, such as static random access Memory (Static Random Access Memory, SRAM for short), electrically erasable programmable Read-Only Memory (Electrically Erasable Programmable Read-Only Memory, EEPROM for short), erasable programmable Read-Only Memory (Erasable Programmable Read-Only Memory, EPROM for short), programmable Read-Only Memory (Programmable Read-Only Memory, PROM for short), read-Only Memory (ROM for short), magnetic Memory, flash Memory, magnetic disk or optical disk.

Example five

The present embodiment also provides a computer readable storage medium, such as a flash memory, a hard disk, a multimedia card, a card memory (e.g., SD or DX memory, etc.), a Random Access Memory (RAM), a Static Random Access Memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a magnetic disk, an optical disk, a server, an App application store, etc., on which a computer program is stored, which when executed by a processor, can implement the following method steps:

step S102: forward modeling is carried out on each fracture-cavity model through the forward modeling observation system so as to obtain the seismic profile of each fracture-cavity model;

step S103: determining the calculated width of each fracture-cavity model according to the seismic section of each fracture-cavity model, and establishing a hierarchical correction model for describing the corresponding relation between the calculated width and the actual width of the fracture-cavity body in different width ranges according to the calculated width and the actual width of all the fracture-cavity models;

step S104: acquiring post-stack seismic data of the ancient river channel to be tested, and determining the seismic attribute of the ancient river channel to be tested according to the post-stack seismic data of the ancient river channel to be tested;

step S105: processing the seismic attributes of the ancient river channel to be detected by a multi-attribute superposition and fusion method to identify the form and the initial seismic abnormal boundary of the ancient river channel to be detected, thereby obtaining the initial plane spread of the ancient river channel to be detected;

step S106: determining the calculated width of the ancient river channel to be measured according to the initial plane spread of the ancient river channel to be measured;

The specific embodiment process of the above method steps can be referred to as embodiment one, and the description of this embodiment is not repeated here.

In summary, the method includes establishing a hierarchical correction model for describing a correspondence between calculated widths and actual widths of a hole body in different width ranges according to forward modeling results of hole body models in different widths; processing the seismic attributes of the ancient river channel to be detected by a multi-attribute superposition and fusion method to identify the form and the initial seismic abnormal boundary of the ancient river channel to be detected, thereby obtaining the initial plane spread of the ancient river channel to be detected; determining the calculated width of the ancient river channel to be measured according to the initial plane spread of the ancient river channel to be measured; and carrying out grading correction on the calculated width of the ancient river channel to be measured by using the grading correction model so as to determine the actual width of the ancient river channel to be measured. According to the method, a hierarchical correction model of the paleo-river width is established based on forward modeling results of the fracture-cavity model, conversion from paleo-river geophysical attribute abnormality to geological abnormality is achieved, accuracy of paleo-river reservoir prediction is improved, reliable technical support is provided for guiding deep carbonate reservoir exploration and development efficiency, and the method has important significance for fine development and increased storage and upper production of carbonate paleo-river reservoirs.

In the several embodiments provided in the embodiments of the present disclosure, it should be understood that the disclosed method may be implemented in other manners. The method embodiments described above are merely illustrative.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

While the embodiments disclosed in this disclosure are described above, the embodiments are presented only to facilitate understanding of the disclosure and are not intended to limit the disclosure. Any person skilled in the art to which this disclosure pertains will appreciate that numerous modifications and variations in form and detail can be made without departing from the spirit and scope of the disclosure, but the scope of the disclosure is to be determined by the appended claims.

Claims

1. The method for correcting the width of the ancient river channel is characterized by comprising the following steps of:

Performing grading correction on the calculated width of the ancient river channel to be measured by using the grading correction model so as to determine the actual width of the ancient river channel to be measured;

according to the seismic section of each fracture-cavity model, determining the calculated width of each fracture-cavity model, comprising the following steps:

determining the calculated width of each fracture-cavity model corresponding to each amplitude threshold according to the boundary of each fracture-cavity model corresponding to each amplitude threshold in the width direction;

according to the calculated widths and the actual widths of all the seam-hole body models, establishing a grading correction model for describing the corresponding relation between the calculated widths and the actual widths of the seam-hole bodies in different width ranges, wherein the grading correction model comprises the following steps:

2. The method of claim 1, wherein the seismic attributes comprise amplitude-class attributes and coherence attributes, wherein the amplitude-class attributes comprise root mean square amplitude attributes, total energy, mid-low frequency energy and high frequency energy in a divided amplitude, and amplitude average curvature; the seismic attributes of the ancient river channel to be detected are processed through a multi-attribute superposition and fusion method to identify the form and the initial seismic abnormal boundary of the ancient river channel to be detected, so that the initial plane layout of the ancient river channel to be detected is obtained, and the method comprises the following steps:

3. The method according to claim 2, wherein the processing of the amplitude class attribute and the coherence attribute of the culvert to be tested by a multi-attribute superposition method to determine an initial seismic anomaly boundary of the culvert to be tested comprises the steps of:

4. The method of claim 1, wherein determining the calculated width of the ancient river channel to be measured based on the initial planar spread of the ancient river channel to be measured comprises the steps of:

5. The method of claim 1, wherein using the hierarchical correction model, performing hierarchical correction on the calculated width of the ancient river channel to be measured to determine an actual width of the ancient river channel to be measured, comprising the steps of:

6. A correction device for ancient river channel width, the device comprising:

taking the combination of the first linear relation and the second linear relation as a grading correction model for describing the corresponding relation between the calculated width and the actual width of the seam hole body in different width ranges;

7. An electronic device comprising a memory and a processor, wherein the memory has stored thereon a computer program which, when executed by the processor, performs the method of correcting the width of a culvert according to any one of claims 1 to 5.

8. A storage medium storing a computer program executable by one or more processors for implementing the method of correcting the width of a culvert according to any one of claims 1 to 5.