Method and system for establishing intrusive rock thickness prediction model, and thickness prediction method

Abstract

The present invention discloses a method for establishing an intrusive rock thickness prediction model, comprising: conducting three-dimensional seismic interpretation on a target area, establishing an intrusive rock geological model containing information on different thicknesses and different intrusion angle combinations; conducting seismic forward modeling and prestack depth migration processing on the intrusive rock geological model to form a corresponding intrusive rock seismic profile model; using the intrusive rock seismic profile model, extracting seismic amplitude response characteristics under information on different thicknesses and different angle combinations, and establishing a prediction initial model for characterizing the correlation between thickness, intrusion angle and seismic response; and correcting the prediction initial model based on actual drilling data of wells drilled in the target area to generate a model suitable for predicting the intrusive rock thickness in the target area. The present invention can accurately predict the thickness of igneous rocks in igneous rock development areas, and provide a reliable basis for reservoir prediction and drilling design.

Description

Technical Field

[0001] The present invention relates to the technical field of igneous rock thickness prediction, and in particular to a method and system for establishing an intrusive rock thickness prediction model, and a thickness prediction method. Background Art

[0002] Intrusive rocks are commonly found in the Sangtamu Formation in the Shunbei area of ​​the Tarim Basin, and the large-scale development of igneous rocks has a great impact on the later drilling design. Therefore, a systematic study on intrusive rocks can better understand the relationship between the seismic response characteristics and geological characteristics of intrusive rocks, and provide a reliable basis for later drilling design.

[0003] At present, unlike the mainstream igneous rock research at home and abroad, the igneous rocks of the Sangtamu Formation in the Shunbei area of ​​Tarim are intrusive rocks, and no obvious volcanic channels have been found, and the scale of intrusion is large. The appearance of intrusive rocks has brought great difficulties to the design of drilling. Since the thickness characteristics of intrusive rocks affect the design and planning of drilling technology, it is necessary to carry out the prediction of intrusive rock thickness.

[0004] Therefore, the prior art needs to provide a model and a corresponding prediction scheme that can realize the while-drilling prediction of the thickness of intrusive rocks, so as to provide a better basis for reservoir prediction and drilling design through the study of intrusive rocks. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for establishing an intrusive rock thickness prediction model, comprising: step one, conducting three-dimensional seismic interpretation on a target area, and establishing an intrusive rock geological model containing information of different thicknesses and different intrusion angle combinations; step two, conducting seismic forward modeling and prestack depth migration processing on the intrusive rock geological model, and forming a corresponding intrusive rock seismic profile model; step three, using the intrusive rock seismic profile model, extracting seismic amplitude response characteristics under the information of different thicknesses and different angle combinations, and establishing an initial prediction model for characterizing the correlation between thickness, intrusion angle and seismic response; step four, correcting the initial prediction model according to actual drilling data of wells drilled in the target area, and generating a model suitable for predicting the intrusive rock thickness in the target area.

[0006] Preferably, in step three, the maximum peak amplitude data corresponding to the igneous rock seismic reflection under different intrusive rock development pattern thicknesses and different angle combinations are extracted from the intrusive rock seismic profile model to form a corresponding statistical data list; the statistical data list is interpolated and fitted to generate the prediction initial model.

[0007] Preferably, a cubic spline interpolation algorithm is used to interpolate the statistical data list.

[0008] Preferably, in step 2, elastic wave seismic forward modeling and prestack depth migration processing are carried out according to the intrusive rock geological model to obtain a forward profile; based on the forward profile combined with the three-dimensional seismic data of the target area, the seismic response characteristics of different intrusive rock development modes in the target area are determined to generate the intrusive rock seismic profile model.

[0009] Preferably, in step 4, the actual intrusion angle information and the actual thickness information of the intrusive rock of multiple wells drilled in the target area are obtained, and the theoretical value of the seismic amplitude attribute at the corresponding position is calculated using the initial prediction model; the actual value of the seismic amplitude attribute of multiple wells drilled in the target area is obtained, based on which, the ratio of the actual value of the seismic amplitude attribute of each well position drilled is first calculated to the corresponding theoretical value, and then the average value of each ratio is calculated to obtain the average amplitude ratio; the average amplitude ratio is loaded as a multiplication factor module to the front end of the seismic response characteristic data input part in the initial prediction model, thereby forming an intrusive rock thickness prediction model.

[0010] On the other hand, the present invention also provides a system for establishing an intrusive rock thickness prediction model, comprising: an intrusive rock development feature generation module, which is configured to carry out three-dimensional seismic interpretation of the target area and establish an intrusive rock geological model containing information on different thicknesses and different intrusion angle combinations; a seismic response feature generation module, which is configured to carry out seismic forward simulation and pre-stack depth migration processing on the intrusive rock geological model to form a corresponding intrusive rock seismic profile model; an initial model generation module, which is configured to use the intrusive rock seismic profile model to extract the seismic amplitude response characteristics under the information on different thicknesses and different angle combinations, and establish a prediction initial model for characterizing the correlation between thickness, intrusion angle and seismic response; a model correction module, which is configured to correct the prediction initial model based on actual drilling data of wells drilled in the target area, and generate a model suitable for predicting the intrusive rock thickness in the target area.

[0011] Preferably, the initial model generation module is further configured to extract the maximum peak amplitude data corresponding to the igneous rock seismic reflection under different intrusive rock development pattern thicknesses and different angle combinations from the intrusive rock seismic profile model, form a corresponding statistical data list, and then interpolate and fit the statistical data list to generate the prediction initial model.

[0012] Preferably, in the initial model generation module, a cubic spline interpolation algorithm is used to perform interpolation processing on the statistical data list.

[0013] Preferably, the seismic response characteristic generating module is further configured to carry out elastic wave seismic forward modeling and prestack depth migration processing according to the intrusive rock geological model to obtain a forward profile, and determine the seismic response characteristics under different intrusive rock development modes in the target area according to the forward profile combined with the three-dimensional seismic data of the target area to generate the intrusive rock seismic profile model.

[0014] In addition, the present invention also provides a method for predicting the thickness of intrusive rocks, the method comprising: step one, obtaining the intrusion angle information and seismic response characteristic information of the intrusive rocks to be predicted in the target area; step two, based on the intrusion angle information and the seismic response characteristic information, using a preset intrusive rock thickness prediction model, determining the seismic amplitude change information under different thickness conditions under a specified intrusion angle, thereby obtaining the intrusive rock thickness from actual drilling data, wherein the intrusive rock thickness prediction model is constructed using the method described above.

[0015] Compared with the prior art, one or more embodiments of the above scheme may have the following advantages or beneficial effects:

[0016] The present invention discloses a method and system for establishing an intrusive rock thickness prediction model, and an intrusive rock thickness prediction method. Specifically, in order to improve the blank of the intrusive rock thickness prediction research in the Sangtamu Formation in the Shunbei area of ​​the Tarim Basin, the present invention starts with different development modes of intrusive rocks and establishes corresponding geological models; forward simulation and prestack depth migration imaging research are carried out on the geological model to obtain the seismic response characteristics of igneous rocks with different development modes; then, by extracting the seismic amplitude response characteristics, the relationship between the igneous rock thickness, the intrusion angle and the seismic response is established to form a theoretical prediction template; finally, the theoretical template is corrected using the actual drilling parameters in the area to obtain the actual thickness prediction model that conforms to the area, thereby realizing the accurate prediction of the igneous rock thickness. The present invention can accurately predict the thickness of igneous rocks in the igneous rock development area, accurately predict the thickness change characteristics of igneous rocks, and further provide a reliable basis for later reservoir prediction and drilling design, with good prediction effect, and broad application and promotion prospects.

[0017] 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 can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0019] Figure 1 It is a step diagram of a method for establishing an intrusive rock thickness prediction model according to an embodiment of the present application.

[0020] Figure 2 It is a specific flow chart of the method for establishing an intrusive rock thickness prediction model according to an embodiment of the present application.

[0021] Figure 3 It is a schematic diagram of the effect of an example of an intrusive rock geological model in the method for establishing an intrusive rock thickness prediction model in an embodiment of the present application.

[0022] Figure 4 It is a schematic diagram of the effect of an example of an intrusive rock seismic profile model in the method for establishing an intrusive rock thickness prediction model in an embodiment of the present application.

[0023] Figure 5 It is a schematic diagram of the effect of an example of predicting an initial model in the method for establishing an intrusive rock thickness prediction model in an embodiment of the present application.

[0024] Figure 6 It is a schematic diagram of the effect of an example of an intrusive rock thickness prediction model in the method for establishing an intrusive rock thickness prediction model in an embodiment of the present application.

[0025] Figure 7 It is a module block diagram of a system for establishing an intrusive rock thickness prediction model according to an embodiment of the present application.

[0026] Figure 8 It is a step diagram of the intrusive rock thickness prediction method according to an embodiment of the present application.

[0027] Fig. 9 It is a schematic diagram of the effects of the first example and the second example of using the intrusive rock thickness prediction method of the embodiment of the present application to realize the igneous rock thickness prediction. DETAILED DESCRIPTION

[0028] The following will describe the implementation methods of the present invention in detail with reference to the accompanying drawings and embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that as long as there is no conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other, and the technical solutions formed are all within the protection scope of the present invention.

[0029] In addition, the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions. Also, although a logical sequence is shown in the flowchart, in some cases, the steps shown or described can be performed in a sequence different from that here.

[0030] Intrusive rocks are commonly found in the Sangtamu Formation in the Shunbei area of ​​the Tarim Basin, and the large-scale development of igneous rocks has a great impact on the later drilling design. Therefore, a systematic study on intrusive rocks can better understand the relationship between the seismic response characteristics and geological characteristics of intrusive rocks, and provide a reliable basis for later drilling design.

[0031] At present, unlike the mainstream igneous rock research at home and abroad, the igneous rocks of the Sangtamu Formation in the Shunbei area of ​​Tarim are intrusive rocks, and no obvious volcanic channels have been found, and the scale of intrusion is large. The appearance of intrusive rocks has brought great difficulties to the design of drilling. Since the thickness characteristics of intrusive rocks affect the design and planning of drilling technology, it is necessary to carry out the prediction of intrusive rock thickness.

[0032] Therefore, in order to solve the above technical problems, the present invention provides a method and system for establishing an intrusive rock thickness prediction model. The method and system first analyze the seismic amplitude response characteristics and intrusive rock development characteristics of the target area; then, establish an initial prediction model for characterizing the correlation between igneous rock thickness, invasion angle and seismic characteristic response; then use the real-time drilling data of the wells drilled in the target area to correct the initial prediction model, so as to form a final intrusive rock thickness prediction model that conforms to the actual geological characteristics of the target area. In addition, the present invention also provides an intrusive rock thickness prediction method. After obtaining the invasion angle information and seismic response characteristic information of other wells to be drilled in the target area, the method uses the intrusive rock thickness prediction model to directly and accurately predict the igneous rock thickness in the target area, thereby providing a better basis for reservoir prediction and drilling design through the study of intrusive rocks.

[0033] Figure 1 It is a step diagram of a method for establishing an intrusive rock thickness prediction model according to an embodiment of the present application. Figure 2 This is a specific flow chart of the method for establishing an intrusive rock thickness prediction model in the embodiment of the present application. Figure 1 and Figure 2 The method for establishing a thickness prediction model for intrusive rocks (hereinafter referred to as "thickness prediction model establishment method") according to the present invention is described.

[0034] like Figure 1As shown, step S110 conducts three-dimensional seismic interpretation on the target area to establish an intrusive rock geological model containing information on different thicknesses and different intrusion angle combinations. In step S110, it is first necessary to determine the area to be studied (target area) and obtain three-dimensional seismic data of the target area. Then, a seismic interpretation study is conducted on the target area. Next, based on the existing geophysical data and seismic interpretation results of the current area to be studied, the development pattern of the intrusive rock in the target area is determined, thereby establishing an intrusive rock geological model containing information on different thicknesses and different intrusion angle combinations. Specifically, in the process of constructing the intrusive rock geological model, the embodiment of the present invention will be based on the statistical analysis results of the rock physical parameters of the target area, and on this basis, further combined with geophysical characteristics, to establish an igneous rock geological model under different thicknesses and different intrusion angles, thereby providing a model basis for subsequent research. Among them, the development pattern of the intrusive rock includes but is not limited to: the spatial distribution of the intrusive rock, the intrusion angle of the intrusive rock, and the thickness of the intrusive rock.

[0035] For example, after obtaining the three-dimensional seismic data of the Shunbei area of ​​the Tarim Basin, the development state of the intrusive rocks of the Sangtamu Formation in the area is studied. Through the development of the three-dimensional seismic interpretation work, it can be known that the intrusive rocks in the area develop at different intrusion angles, and there are also obvious differences in the seismic amplitude energy, which indicates that the thickness of the intrusive rocks in the area also changes. According to the analysis of step S110, an igneous rock geological model (intrusive rock geological model) under the conditions of different thicknesses and different intrusion angle combinations is established. Figure 3 FIG. 1 is a schematic diagram showing the effect of an example of an intrusive rock geological model in the method for establishing an intrusive rock thickness prediction model in an embodiment of the present application. Figure 3 As shown, the figure shows the spatial distribution characteristics of the intrusive rocks in the area, and shows that the intrusion angles of the intrusive rocks in the area are 0°, 15°, 30°, and 45°, and the thickness of the intrusive rocks are 20m and 40m respectively.

[0036] After the construction of the intrusive rock geological model is completed, the process proceeds to step S120 . Step S120 performs seismic forward simulation and prestack depth migration processing on the intrusive rock geological model constructed in step S110 to form a corresponding intrusive rock seismic profile model.

[0037] Specifically, in step S120, elastic wave seismic forward modeling and prestack depth migration processing are first carried out in sequence according to the intrusive rock geological model constructed in step S110, so as to obtain a forward profile. Then, according to the currently obtained forward profile, combined with the three-dimensional seismic data of the target area, the seismic response characteristics of different intrusive rock development modes in the target area are determined, and an intrusive rock seismic profile model is generated, so as to obtain seismic identification information of the intrusive rock in the target area.

[0038] Figure 4The figure is a schematic diagram of the effect of an example of the seismic profile model of an intrusive rock in the method for establishing an intrusive rock thickness prediction model in the embodiment of the present application. In step S120 of the embodiment of the present invention, based on the establishment of the geological model, wave equation forward simulation and prestack depth migration imaging processing are carried out, and the seismic response characteristics corresponding to different development modes of the intrusive rock formed under the combination of different intrusion angles and different thicknesses are clarified, that is, the seismic profile model of the intrusive rock, reference Figure 4 .

[0039] After completing the seismic response characteristic analysis for the intrusive rock in the target area, the process proceeds to step S130. Step S130 uses the seismic profile model of the intrusive rock constructed in step S120 to extract the seismic amplitude response characteristics under different thickness and different angle combination information, and establishes a prediction initial model for characterizing the correlation between thickness, intrusion angle and seismic response.

[0040] In step S130, it is necessary to first extract the maximum peak amplitude data corresponding to the seismic reflection characteristics of igneous rocks under different intrusive rock development modes (formed by different thicknesses and different intrusion angles) from the intrusive rock seismic profile model constructed in step S120 (reference Figure 4 ), thereby using these maximum peak amplitude data to form a corresponding statistical data list.

[0041] Then, the currently obtained statistical data list is interpolated and fitted to generate an initial prediction model, thereby obtaining a theoretical prediction model. In order to obtain an accurate theoretical prediction model, the embodiment of the present invention adopts a cubic spline interpolation algorithm to complete the interpolation of a series of maximum peak amplitude data in the statistical data list, and fits the interpolation results to form an initial prediction model.

[0042] Figure 5 : is a schematic diagram of the effect of an example of the prediction initial model in the method for establishing an intrusive rock thickness prediction model in the embodiment of the present application. Since the prediction initial model is a model obtained by data interpolation and fitting, in the embodiment of the present invention, the prediction initial model is a three-dimensional information feature model based on quantitative data fitting, which is used to represent the correlation between the intrusive rock thickness, the intrusion angle and the seismic amplitude response data. Figure 5 .

[0043] In this way, step S130 in the steps of the embodiment of the present invention will first extract the maximum peak amplitude data in the seismic reflection characteristics of igneous rocks (intrusive rocks) under different intrusive rock development modes from the intrusive rock seismic profile model, and then interpolate and fit these maximum peak amplitude data to generate an initial prediction model, and then obtain the relationship between the three types of attribute information: igneous rock thickness, intrusion angle and seismic response.

[0044] After the theoretical prediction model is constructed, the process proceeds to step S140 to calibrate the current theoretical model using actual data. Step S140 calibrates the initial prediction model constructed in step S130 based on actual drilling data of wells drilled in the target area to generate a model suitable for predicting the thickness of intrusive rocks in the target area.

[0045] In the process of implementing the present invention, the inventors found that considering the difference between the theoretical model and the actual geological conditions, the model representing the relationship between the actual drilling thickness, the intrusion angle and the amplitude response information cannot be directly applied to the prediction of the actual igneous rock thickness, and the theoretical prediction model needs to be corrected to obtain an igneous rock thickness prediction template that conforms to the target area. In step S140, it is necessary to obtain the seismic amplitude response characteristic data, the intrusive rock distribution characteristics, the intrusion angle information and the intrusive rock thickness information for the current drilling location, based on which, the initial prediction model is corrected to obtain an intrusive rock thickness prediction model that conforms to the actual geological characteristics of the target area.

[0046] Specifically, in the process of correcting the initial prediction model, it is first necessary to obtain the actual thickness information and intrusion angle information of the intrusive rock at the (multiple) drilled positions in the target area, and use the initial prediction model to calculate the theoretical value of the seismic amplitude attribute at the corresponding position; then obtain the actual value of the seismic amplitude attribute of the multiple drilled positions in the target area, based on which, calculate the ratio of the actual value of the seismic amplitude attribute of each drilled position to the theoretical value at each position, and then calculate the average of multiple ratios to obtain the average amplitude ratio; finally, load the current average amplitude ratio as a multiplication factor module to the front end of the seismic response data input part in the initial prediction model, thereby forming an intrusive rock thickness prediction model and completing the correction of the initial model. Figure 5 and Figure 6 , the seismic amplitude value input to the initial prediction model is small to large, and after obtaining the parameters revealed by the actual drilling, a thickness prediction model that conforms to the actual parameters is constructed. In this way, the seismic response data that needs to be input to the initial prediction model is multiplied by the average amplitude ratio before the initial prediction model predicts a more accurate quantitative value of the intrusive rock thickness.

[0047] Figure 6It is a schematic diagram of the effect of an example of an intrusive rock thickness prediction model in the method for establishing an intrusive rock thickness prediction model in an embodiment of the present application. For example, after obtaining the actual drilling data of the Shunbei 4 well in the target area, the intrusive rock thickness information, intrusion angle information and seismic amplitude information at the current well are obtained based on such data. According to the actual situation, there are two sets of intrusive rocks at the well, with thickness parameters of 28m and 39m respectively, and inclination parameters of 9.54° and 3.89° respectively; the amplitude attributes are 6050 and 6950 respectively; according to the theoretical template, the calculated amplitude attributes are 1715 and 2194 respectively, so that the average amplitude ratio is calculated to be 3.35. In this way, the theoretical prediction template is corrected using the above attribute parameters to obtain an igneous rock thickness prediction template that conforms to the Shunbei 4 well area, such as Figure 6 As shown. The theoretical model (prediction initial model) established by the embodiment of the present invention reveals a general law, which can be applied to actual data, but the absolute value may not be applicable to actual data. Therefore, through the actual drilling point, the law followed by this theoretical model (prediction initial model) is corrected, so that the model for predicting the thickness of intrusive rock in the target area (intrusive rock thickness prediction model) established by the embodiment of the present invention is consistent with the law and the characteristics of the actual data in this area. Figure 5 and Figure 6 It is knowable.

[0048] On the other hand, based on the method for establishing an intrusive rock thickness prediction model described in the above embodiment, an embodiment of the present invention also provides a system for establishing an intrusive rock thickness prediction model (hereinafter referred to as "thickness prediction model establishment system"). Figure 7 1 is a block diagram of a system for establishing an intrusive rock thickness prediction model according to an embodiment of the present application. Figure 7 As shown, the thickness prediction model establishment system described in the present invention includes: an intrusive rock development feature generation module 71, a seismic response feature generation module 72, an initial model generation module 73 and a model correction module 74.

[0049] Further, the intrusive rock development feature generation module 71 is implemented according to the method described in step S110 above, and is configured to carry out three-dimensional seismic interpretation of the target area, and establish an intrusive rock geological model containing information of different thicknesses and different intrusion angle combinations. The seismic response feature generation module 72 is implemented according to the method described in step S120 above, and is configured to carry out seismic forward simulation and pre-stack depth migration processing on the intrusive rock geological model to form a corresponding intrusive rock seismic profile model. The initial model generation module 73 is implemented according to the method described in step S130 above, and is configured to use the intrusive rock seismic profile model to extract the seismic amplitude response characteristics under different thicknesses and different angle combinations, and establish a prediction initial model for characterizing the correlation between thickness, intrusion angle and seismic response. The model correction module 74 is implemented according to the method described in step S140 above, and is configured to correct the prediction initial model according to the actual drilling data of the wells drilled in the target area, and generate a model suitable for predicting the thickness of intrusive rocks in the target area.

[0050] Preferably, the seismic response characteristic generation module 72 is further configured to carry out elastic wave seismic forward modeling and pre-stack depth migration processing according to the intrusive rock geological model to obtain a forward profile, and determine the seismic response characteristics of different intrusive rock development modes in the target area according to the forward profile combined with the three-dimensional seismic data of the target area to generate the intrusive rock seismic profile model.

[0051] Preferably, the initial model generation module 73 is further configured to extract the maximum peak amplitude data corresponding to the igneous rock seismic reflection under different intrusive rock development mode thicknesses and different angle combinations from the intrusive rock seismic profile model, form a corresponding statistical data list, and then interpolate and fit the statistical data list to generate a prediction initial model. In the initial model generation module, a cubic spline interpolation algorithm is used to interpolate the statistical data list.

[0052] In addition, based on the above thickness prediction model establishment method, an embodiment of the present invention also provides a method for predicting the thickness of intrusive rocks. The intrusive rock thickness prediction model constructed by the above thickness prediction model establishment method is used to carry out thickness prediction work for intrusive rocks at other locations in the target area (for example, intrusive rocks at undrilled locations), providing necessary support for reservoir research, drilling design, etc., and reducing exploration and development risks.

[0053] Figure 8 1 is a step diagram of the intrusive rock thickness prediction method of the present application embodiment. Figure 8As shown, first, step S801 obtains the intrusion angle information and seismic response characteristic information of the intrusive rock to be predicted in the target area. Thus, step S801 is used to obtain the intrusion angle information and seismic response characteristic information of the intrusive rock at the position where no well is drilled or no well is located in the target area, and then enters step S802.

[0054] Step S802 determines the seismic amplitude change (curve) information under different thickness conditions under the specified intrusion angle according to the intrusion angle information and seismic response characteristic information obtained in step S801, using the preset intrusion rock thickness prediction model, so as to obtain the intrusion rock thickness from the actual drilling data. In step S802, firstly, according to the intrusion angle information and seismic response characteristic information at the predicted position obtained in step S801, the intrusion rock thickness prediction model constructed by the above-mentioned thickness prediction model establishment method is used to obtain the first curve corresponding to the current intrusion angle condition. Among them, the first curve is the seismic amplitude change curve that changes with different thickness conditions. Then, using the current first curve, according to the seismic amplitude response characteristic data (obtained from the logging data) obtained in real time during the drilling process, accurate intrusion rock thickness data is quickly obtained.

[0055] Fig. 9 It is a schematic diagram of the effects of the first example and the second example of using the intrusive rock thickness prediction method of the embodiment of the present application to realize the igneous rock thickness prediction. Fig. 9 (a) Fig. 9 (b) shows the prediction results of two igneous rocks respectively. Fig. 9 a shows the seismic amplitude variation curve under different thickness conditions when the intrusion angle is 9.54°. The asterisk mark in the curve indicates the actual thickness of the intrusive rock corresponding to the seismic amplitude obtained during the actual drilling process, which is 28m thick; the circle mark indicates the predicted thickness of the intrusive rock corresponding to the seismic amplitude obtained during the actual drilling process, which is 30m thick. Fig. 9 b shows the seismic amplitude variation curve under different thickness conditions when the intrusion angle is 3.89°. The asterisk in the curve indicates the actual thickness of the intrusive rock corresponding to the seismic amplitude obtained during the actual drilling process, which is 39m; the circle indicates the predicted thickness of the intrusive rock corresponding to the seismic amplitude obtained during the actual drilling process, which is 36m. Therefore, the intrusive rock thickness prediction method provided in the embodiment of the present invention has a high prediction accuracy.

[0056] The present invention discloses a method and system for establishing an intrusive rock thickness prediction model, and an intrusive rock thickness prediction method. Specifically, in order to improve the blank of the intrusive rock thickness prediction research in the Sangtamu Formation in the Shunbei area of ​​the Tarim Basin, the present invention starts with different development modes of intrusive rocks and establishes corresponding geological models; forward simulation and prestack depth migration imaging research are carried out on the geological model to obtain the seismic response characteristics of igneous rocks with different development modes; then, by extracting the seismic amplitude response characteristics, the relationship between the igneous rock thickness, the intrusion angle and the seismic response is established to form a theoretical prediction template; finally, the theoretical template is corrected using the actual drilling parameters in the area to obtain the actual thickness prediction model that conforms to the area, thereby realizing the accurate prediction of the igneous rock thickness. The present invention can accurately predict the thickness of igneous rocks in the igneous rock development area, accurately predict the thickness change characteristics of igneous rocks, and further provide a reliable basis for later reservoir prediction and drilling design, with good prediction effect, and broad application and promotion prospects.

[0057] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any person familiar with the technology within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

[0058] It should be understood that the embodiments disclosed in the present invention are not limited to the specific structures, processing steps or materials disclosed herein, but should be extended to equivalent substitutions of these features understood by ordinary technicians in the relevant field. It should also be understood that the terms used herein are only used for the purpose of describing specific embodiments and are not meant to be limiting.

[0059] The "one embodiment" or "embodiment" mentioned in the specification means that the specific features, structures or characteristics described in conjunction with the embodiment are included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment" or "embodiment" appearing in various places throughout the specification do not necessarily refer to the same embodiment.

[0060] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A method for establishing an intrusive rock thickness prediction model, characterized in that: include: Step 1: Conduct 3D seismic interpretation in the target area and establish an intrusive rock geological model containing information on different thicknesses and different intrusion angles; Step 2: Performing seismic forward modeling and pre-stack depth migration processing on the intrusive rock geological model to form a corresponding intrusive rock seismic profile model; Step 3: using the intrusive rock seismic profile model, extracting the seismic amplitude response characteristics under the combination of different thicknesses and different angles, and establishing a prediction initial model for characterizing the correlation between thickness, intrusion angle and seismic response, which includes: extracting the maximum peak amplitude data corresponding to the igneous rock seismic reflection under different intrusive rock development mode thicknesses and different angle combinations from the intrusive rock seismic profile model, forming a corresponding statistical data list, and then interpolating and fitting the statistical data list to generate the prediction initial model; Step 4: According to the actual drilling data of the wells drilled in the target area, the initial prediction model is corrected to generate a model suitable for predicting the thickness of the intrusive rock in the target area. The step 4 includes: Obtain the actual intrusion angle information and actual thickness information of intrusive rocks at multiple wells drilled in the target area, and use the initial prediction model to calculate the theoretical value of the seismic amplitude attribute at the corresponding location; The actual values ​​of seismic amplitude attributes of multiple wells in the target area are obtained, and based on this, the ratio of the actual value of the seismic amplitude attribute of each well location to the corresponding theoretical value is first calculated, and then the average value of each ratio is calculated to obtain the average amplitude ratio; The average amplitude ratio is loaded as a multiplication factor module into the front end of the seismic response characteristic data input part in the initial prediction model, thereby forming an intrusive rock thickness prediction model.

2. The method according to claim 1, characterized in that The statistical data list is interpolated using a cubic spline interpolation algorithm.

3. The method according to claim 1 or 2, characterized in that: In the step 2, According to the intrusive rock geological model, elastic wave seismic forward modeling and prestack depth migration processing are carried out to obtain a forward modeling profile; According to the forward modeling section combined with the three-dimensional seismic data of the target area, the seismic response characteristics of different intrusive rock development modes in the target area are determined, and the intrusive rock seismic section model is generated.

4. A system for establishing an intrusive rock thickness prediction model, characterized in that: include: An intrusive rock development feature generation module, which is configured to conduct three-dimensional seismic interpretation of the target area and establish an intrusive rock geological model containing information on different thicknesses and different intrusion angles; A seismic response feature generation module configured to perform seismic forward modeling and prestack depth migration processing on the intrusive rock geological model to form a corresponding intrusive rock seismic profile model; An initial model generation module is configured to use the intrusive rock seismic profile model to extract the seismic amplitude response characteristics under the different thickness and different angle combination information, and establish a prediction initial model for characterizing the correlation between thickness, intrusion angle and seismic response, wherein the initial model generation module is further configured to extract the maximum peak amplitude data corresponding to the igneous rock seismic reflection under different intrusive rock development mode thickness and different angle combinations from the intrusive rock seismic profile model to form a corresponding statistical data list, and then interpolate and fit the statistical data list to generate the prediction initial model; The model correction module is configured to correct the initial prediction model according to the actual drilling data of the wells drilled in the target area to generate a model suitable for predicting the thickness of the intrusive rock in the target area, wherein: The model correction module is further configured to obtain actual intrusion angle information and actual thickness information of intrusive rocks of multiple wells that have been drilled in the target area, calculate theoretical values ​​of seismic amplitude attributes at corresponding positions using the initial prediction model, and then obtain actual values ​​of seismic amplitude attributes of multiple wells that have been drilled in the target area, and based on this, first calculate the ratio of the actual value of the seismic amplitude attribute of each well location to the corresponding theoretical value, and then calculate the average value of each ratio to obtain an average amplitude ratio; finally, load the average amplitude ratio as a multiplication factor module into the front end of the seismic response characteristic data input part in the initial prediction model, thereby forming an intrusive rock thickness prediction model.

5. The system according to claim 4, characterized in that In the initial model generation module, a cubic spline interpolation algorithm is used to interpolate the statistical data list.

6. The system according to claim 4 or 5, characterized in that: The seismic response characteristic generation module is further configured to carry out elastic wave seismic forward modeling and pre-stack depth migration processing according to the intrusive rock geological model to obtain a forward profile, and to determine the seismic response characteristics under different intrusive rock development modes in the target area according to the forward profile combined with the three-dimensional seismic data of the target area to generate the intrusive rock seismic profile model.

7. A method for predicting the thickness of an intrusive rock, characterized in that: The method comprises: Step 1: obtaining intrusion angle information and seismic response characteristic information of the intrusive rock at the location to be predicted in the target area; Step 2: According to the intrusion angle information and the seismic response characteristic information, a preset intrusive rock thickness prediction model is used to determine the seismic amplitude change information under different thickness conditions under a specified intrusion angle, thereby obtaining the intrusive rock thickness from actual drilling data, wherein the intrusive rock thickness prediction model is constructed using the method described in any one of claims 1 to 3.

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