A fine reservoir prediction method for carbonate fractured-vug reservoirs and related device

Abstract

This invention discloses a refined reservoir prediction method and related apparatus for fracture-vuggy reservoirs in carbonate rocks, belonging to the field of reservoir prediction in oil and gas exploration. First, the invention performs coherence enhancement on the original post-stack seismic data. Then, after calibrating the coherence enhancement value, a threshold is determined. The coherence enhancement value is compared with this threshold to obtain the fracture-vuggy reservoir and its boundary range. Next, post-stack deterministic inversion is performed based on the original seismic data. The P-wave impedance boundary between the vuggy reservoir and the surrounding rock is determined using wells that have drilled into the vuggy reservoir. This boundary value is used to refine the post-stack deterministic inversion, thus obtaining the vuggy reservoir and its boundary range. Finally, the predicted fracture-vuggy reservoir is removed from the vuggy reservoir to obtain the fracture-pore type reservoir and its boundary range. This invention indirectly obtains the distribution range of fracture-pore type reservoirs through seismic attributes and post-stack deterministic inversion, achieving accurate prediction of fracture-pore type reservoirs.

Description

Technical Field

[0001] This invention belongs to the field of reservoir prediction in oil and gas exploration, and in particular, it is a refined reservoir prediction method and related device for carbonate fracture-vuggy reservoirs. Background Technology

[0002] Carbonate reservoirs in oilfields are mainly composed of cave and fracture-pore type reservoirs, which are characterized by irregular shapes and non-uniform distribution, making reservoir prediction extremely difficult. Conventional inversion methods cannot adequately describe their reservoir distribution characteristics.

[0003] Currently, carbonate fracture-vuggy reservoirs in the Tarim Oilfield can be divided into two categories: Category I reservoirs refer to cave-type reservoirs with large to relatively large reservoir spaces, and Category II reservoirs refer to fracture-vuggy reservoirs with relatively large reservoir spaces. Reservoir prediction methods for carbonate fracture-vuggy reservoirs generally fall into two categories. One method uses seismic attributes to qualitatively describe the fracture-vuggy reservoir, such as using coherence attributes and structural tensor attributes to qualitatively characterize the reservoir boundary. Then, a threshold is applied to refine the obtained attributes, thereby characterizing the boundary of the fracture-vuggy reservoir. However, the threshold is usually determined based on wellbore engineering anomalies such as ventilation and leakage. While this method can characterize the outline of the fracture-vuggy reservoir, it does not further subdivide the interior of the reservoir, resulting in a relatively coarse characterization. Furthermore, the results from different attribute characterizations vary significantly, leading to uncertainty in the prediction results for fracture-vuggy reservoirs. Another approach is to qualitatively or semi-quantitatively characterize fractured-vuggy reservoirs using seismic inversion. This method closely integrates well and seismic analysis. First, rock physics analysis is performed on the target stratigraphic interval within the study area to determine the elastic parameter response ranges of cavernous, fracture-void, and non-reservoir types. Then, seismic inversion is performed based on seismic data to obtain the seismic inversion result data volume. Finally, the seismic inversion data volume is interpreted based on the well rock physics analysis results to obtain the distribution of cavernous, fracture-void, and non-reservoir types. However, due to limitations in resolution and accuracy of seismic inversion results, this method can only achieve relatively accurate predictions of cavernous reservoirs within the sub-type of fractured-vuggy reservoirs. The distribution of fracture-void reservoirs obtained using this method is inaccurate, and conventional seismic inversion methods cannot achieve relatively accurate predictions of fracture-void reservoirs within the sub-type of fractured-vuggy reservoirs.

[0004] In recent years, some improvements have been made to seismic inversion of fracture-vuggy reservoirs in carbonate rocks, with the development of phasing-controlled inversion methods. These methods organically combine the spatiotemporal distribution of seismic facies with seismic inversion calculations, minimizing boundary effects and improving the accuracy of the inversion results. However, this method still only predicts the distribution range of fracture-vuggy reservoirs by combining seismic inversion with well logging petrophysical analysis; it does not help in the accurate prediction of the subdivisions within fracture-vuggy reservoirs. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a refined reservoir prediction method and related apparatus for carbonate fracture-vuggy reservoirs.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] A refined reservoir prediction method for fractured-vuggy carbonate reservoirs includes the following steps:

[0008] Step 1: Based on the original post-stack seismic data, perform coherent enhancement attribute analysis. Use well logging to interpret the reservoir top location to calibrate the coherent enhancement attribute. Use the coherent enhancement attribute value corresponding to the reservoir top location interpreted by well logging as a threshold. Based on the relationship between the coherent enhancement attribute value and the threshold, determine the predicted fracture-vuggy reservoir and its boundary.

[0009] Post-stack deterministic inversion is performed on the original post-stack seismic data to obtain the boundary value of the P-wave impedance of the cavernous reservoir and the surrounding rock; the post-stack deterministic inversion results are then sculpted using the boundary value to obtain the predicted cavernous reservoir and its boundary.

[0010] Step 2: Based on the predicted fracture-vuggy reservoir, remove the cavernous reservoir to obtain the fracture-vuggy reservoir and its boundary range.

[0011] Furthermore, in step 1, the determination is made based on the relationship between the coherence enhancement attribute value and the threshold, specifically as follows:

[0012] The coherent enhancement attribute value greater than the threshold is defined as 0, corresponding to the surrounding rock; all coherent enhancement attribute values ​​less than or equal to the threshold are defined as 1, corresponding to the fractured-vuggy reservoir, thus obtaining the fractured-vuggy reservoir and its boundary range.

[0013] Furthermore, in step 1, the post-stack deterministic inversion results are sculpted using the aforementioned boundary values ​​to obtain the predicted cavernous reservoir and its boundary range, specifically as follows:

[0014] A deterministic inversion result value greater than the threshold value is defined as 0, representing the surrounding rock;

[0015] A deterministic inversion result value less than or equal to the boundary value is defined as 1, representing a cavernous reservoir, thus obtaining the cavernous reservoir and its boundary range.

[0016] Furthermore, step 2 specifically involves:

[0017] The definition value of fracture-vuggy reservoir is subtracted from the definition value of cavernous reservoir by the predicted definition value. If the difference is 1, it represents fracture-vuggy reservoir; if the difference is 0, it represents surrounding rock. This gives us the fracture-vuggy reservoir and its boundary.

[0018] Furthermore, in step 1, the boundary value of the P-wave impedance between the cavernous reservoir and the surrounding rock is obtained, specifically as follows:

[0019] Well logging rock physics analysis was performed on wells that encountered cave-type reservoirs in the work area to obtain the P-wave impedance distribution map of the cave-type reservoir and the surrounding rock, and then the boundary value of the P-wave impedance between the cave-type reservoir and the surrounding rock was determined.

[0020] Furthermore, the longitudinal wave impedance of the cavernous reservoir and the surrounding rock in step (1) is taken from the same well that encountered the cavernous reservoir.

[0021] A fine reservoir prediction device for fracture-vuggy reservoirs in carbonate rocks includes a fracture-vuggy and cavernous reservoir prediction module and a fracture-vuggy reservoir prediction module.

[0022] The fractured-vuggy and cavernous reservoir prediction module is used to generate coherent enhancement attributes based on the original post-stack seismic data, use well logging to interpret the reservoir top position to calibrate the coherent enhancement attribute volume, use the coherent enhancement attribute value corresponding to the well logging interpreted reservoir top position as a threshold, and make a judgment based on the relationship between the coherent enhancement attribute value and the threshold to obtain the fractured-vuggy reservoir and its boundary.

[0023] It is also used to perform post-stack deterministic inversion on the original post-stack seismic data and obtain the boundary value of the P-wave impedance of the cavernous reservoir and the surrounding rock; the boundary value is used to sculpt the post-stack deterministic inversion results to obtain the cavernous reservoir and its boundary.

[0024] The fracture-void reservoir prediction module is used to remove cavernous reservoirs based on the predicted fracture-void reservoirs, thereby obtaining the fracture-void reservoirs and their boundary ranges.

[0025] Furthermore, the fractured-vuggy and cavernous reservoir prediction module includes a fractured-vuggy reservoir prediction unit and a cavernous reservoir prediction unit;

[0026] The fractured-vuggy reservoir prediction unit is used to generate coherent enhancement attributes based on the original post-stack seismic data. The coherent enhancement attribute volume is calibrated by interpreting the reservoir top position using well logging. The coherent enhancement attribute value corresponding to the reservoir top position interpreted by well logging is used as a threshold. The relationship between the coherent enhancement attribute value and the threshold is used to determine the fractured-vuggy reservoir and its boundary.

[0027] The cavernous reservoir prediction unit is used to perform post-stack deterministic inversion on the original post-stack seismic data and obtain the boundary value of the P-wave impedance between the cavernous reservoir and the surrounding rock; the boundary value is used to sculpt the post-stack deterministic inversion results to obtain the cavernous reservoir and its boundary.

[0028] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the steps of the above-described fine reservoir prediction method for carbonate fracture-vuggy reservoirs.

[0029] A computer-readable storage medium storing a computer program, the computer program being executed by a processor of the steps of the fine reservoir prediction method for carbonate fracture-vuggy reservoirs described above.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] This invention provides a refined reservoir prediction method for fracture-vuggy reservoirs in carbonate rocks. First, coherence enhancement attributes are generated based on raw post-stack seismic data. The coherence enhancement attribute values ​​are then calibrated using the reservoir top location interpreted from well logging to determine a threshold. The coherence enhancement attribute values ​​are compared with this threshold to obtain the fracture-vuggy reservoir and its boundary range. Next, post-stack deterministic inversion is performed based on the raw post-stack seismic data. The P-wave impedance boundary between the cavernous reservoir and the surrounding rock is determined using wells that have encountered cavernous reservoirs. This boundary value is used to refine the post-stack deterministic inversion results, thus obtaining the cavernous reservoir and its boundary range. Since wellbore P-wave impedance is difficult to accurately distinguish between cavernous and fracture-void reservoirs, fracture-void reservoirs are difficult to directly identify through inversion. Since fracture-vuggy reservoirs can be broadly divided into cavernous and fracture-void reservoirs, the predicted fracture-vuggy reservoir is used to remove the cavernous reservoir, thus obtaining the fracture-void reservoir and its boundary range, achieving further accurate prediction of fracture-vuggy reservoirs. This invention enables more accurate prediction of fracture-void reservoirs, a sub-category of fracture-void reservoirs. Compared to the traditional method of directly predicting the boundaries of fracture-void reservoirs through seismic inversion combined with well logging petrophysical analysis, this method can indirectly obtain the distribution range of fracture-void reservoirs by combining seismic attributes and post-stack deterministic inversion, thus achieving a more accurate prediction of fracture-void reservoirs.

[0032] The present invention provides a fine reservoir prediction device for fractured-vuggy carbonate reservoirs, which includes specific modules for performing the above-mentioned working method.

[0033] This invention provides a computer device and storage medium for a refined reservoir prediction method for fractured-vuggy carbonate reservoirs, which implements the specific steps of the above-mentioned working method. Attached Figure Description

[0034] Figure 1 This is a flowchart of the present invention;

[0035] Figure 2 This is the original seismic profile of the well.

[0036] Figure 3 To interpret the coherent enhanced attribute map after reservoir top calibration by overlaying well logging of original post-stack seismic data profiles;

[0037] Figure 4 A diagram showing the fractured-vuggy reservoir and its boundary range;

[0038] Figure 5 The image shows the longitudinal wave impedance distribution of the cave-type reservoir and surrounding rock above ground.

[0039] Figure 6 A graph showing the P-wave impedance results obtained from deterministic inversion based on the original seismic data;

[0040] Figure 7 Map showing the cavernous reservoir and its distribution range, sculpted based on deterministic inversion results;

[0041] Figure 8 The final map showing the fracture-pore type reservoir and its distribution range;

[0042] Figure 9 This is a fracture-pore type reservoir map obtained by combining seismic inversion results with well logging petrophysical analysis. Detailed Implementation

[0043] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0044] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0045] To improve the reservoir prediction accuracy of fracture-void reservoirs, a sub-category of fracture-void reservoirs, this invention uses seismic attributes to predict fracture-void reservoirs based on the original post-stack seismic data, and simultaneously uses post-stack deterministic inversion to predict cavern reservoirs. By removing cavern reservoirs from the predicted fracture-void reservoirs, the fracture-void reservoirs and their distribution range are obtained. This enables further prediction of fracture-void reservoirs within the sub-category of fracture-void reservoirs. This invention plays an important role in correctly understanding the sub-categories and distribution ranges of fracture-void reservoirs.

[0046] The present invention will now be described in further detail with reference to the accompanying drawings:

[0047] See Figure 1 , Figure 1 The flowchart of this invention illustrates a refined reservoir prediction method for fractured-vuggy carbonate reservoirs, comprising the following steps:

[0048] Step 1: Perform coherence enhancement attributes based on the original post-stack seismic data;

[0049] Step 2: Use the reservoir top interpreted by well logging to calibrate the coherent enhancement attribute value, and use the coherent enhancement attribute value corresponding to the reservoir top position interpreted by well logging as the threshold;

[0050] Step 3: Define the coherence enhancement attribute value greater than the threshold as 0, representing the surrounding rock; define all coherence enhancement attribute values ​​less than or equal to the threshold as 1, representing fractured-vuggy reservoirs, thereby obtaining the fractured-vuggy reservoir and its boundary range.

[0051] Step 4: Select wells in the work area that encounter cave-like reservoirs and perform well logging rock physics analysis to determine the boundary value of the longitudinal wave impedance between the cave-like reservoir and the surrounding rock.

[0052] Step 5: Perform post-stack deterministic inversion based on the original post-stack seismic data;

[0053] Step 6: Use this boundary value to sculpt the post-stack deterministic inversion results. Deterministic inversion result values ​​greater than this boundary value are defined as 0, representing surrounding rock, and values ​​less than or equal to this boundary value are defined as 1, representing cavernous reservoirs, thus obtaining the cavernous reservoirs and their boundary range.

[0054] Step 7: Subtract the cavernous reservoir from the predicted fracture-cavity reservoir. A value of 1 represents a fracture-cavity reservoir, and a value of 0 represents the surrounding rock, thus obtaining the fracture-cavity reservoir and its boundary range.

[0055] Through the above specific steps, a more accurate prediction of fracture-void reservoirs, a sub-category of fracture-void reservoirs, is achieved. Compared to the traditional method of directly predicting the boundaries of fracture-void reservoirs through seismic inversion combined with well logging petrophysical analysis, this method can indirectly obtain the distribution range of fracture-void reservoirs by combining seismic attributes and post-stack deterministic inversion, thus achieving a more accurate prediction of fracture-void reservoirs.

[0056] This invention also provides a fine reservoir prediction device for fracture-vuggy reservoirs in carbonate rocks, including a fracture-vuggy and cavernous reservoir prediction module and a fracture-void reservoir prediction module. The fracture-vuggy and cavernous reservoir prediction module is used to perform coherent enhancement attribute analysis based on raw seismic data, using well logging interpretation of the reservoir top position to calibrate the coherent enhancement attribute volume, using the coherent enhancement attribute value corresponding to the well logging interpretation of the reservoir top position as a threshold, and judging based on the relationship between the coherent enhancement attribute value and the threshold to obtain the fracture-vuggy reservoir and its boundary. It is also used to perform post-stack deterministic inversion on the raw post-stack seismic data and obtain the boundary value of the P-wave impedance between the cavernous reservoir and the surrounding rock, using the boundary value to refine the post-stack deterministic inversion result to obtain the cavernous reservoir and its boundary. The fracture-void reservoir prediction module is used to remove the cavernous reservoir based on the predicted fracture-vuggy reservoir, thereby obtaining the fracture-void reservoir and its boundary range.

[0057] In one embodiment, a computer device is provided, which may be a server. The computer device includes a processor, memory, a network interface, and a database connected via a system bus. The processor of the computer device provides computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. When the computer program is executed by the processor, it implements a method for operating a fine reservoir prediction device for carbonate fracture-vuggy reservoirs.

[0058] In one embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it performs the following steps: Step 1: Based on the original post-stack seismic data, coherent enhancement attributes are generated. The coherent enhancement attributes are calibrated using the reservoir top location interpreted by well logging. The coherent enhancement attribute value corresponding to the reservoir top location interpreted by well logging is used as a threshold. The predicted fracture-vuggy reservoir and its boundary are obtained based on the relationship between the coherent enhancement attribute value and the threshold. Post-stack deterministic inversion is performed on the original post-stack seismic data, and the boundary value of the P-wave impedance of the cavernous reservoir and the surrounding rock is obtained. The post-stack deterministic inversion result is sculpted using the boundary value to obtain the predicted fracture-vuggy reservoir and its boundary. Step 2: The cavernous reservoir is removed from the predicted fracture-vuggy reservoir to obtain the fracture-void reservoir and its boundary.

[0059] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, it performs the following steps: Step 1: Based on the original post-stack seismic data, coherent enhancement attributes are generated. The coherent enhancement attributes are calibrated using the reservoir top location interpreted by well logging. The coherent enhancement attribute value corresponding to the reservoir top location interpreted by well logging is used as a threshold. The predicted fracture-vuggy reservoir and its boundary are obtained based on the relationship between the coherent enhancement attribute value and the threshold. Post-stack deterministic inversion is performed on the original post-stack seismic data, and the boundary value of the P-wave impedance of the cavernous reservoir and the surrounding rock is obtained. The post-stack deterministic inversion result is sculpted using the boundary value to obtain the predicted fracture-vuggy reservoir and its boundary. Step 2: The cavernous reservoir is removed from the predicted fracture-vuggy reservoir to obtain the fracture-void reservoir and its boundary.

[0060] Example

[0061] See Figure 2 , Figure 2 This is the original seismic profile of the well.

[0062] See Figure 3 , Figure 3 This is a coherent enhancement attribute map for the reservoir top calibration after overlaying the original seismic profile with well logging interpretation. First, coherent enhancement attributes are generated based on the original seismic data. The threshold for coherent enhancement attributes is determined by calibrating the reservoir top according to the well logging interpretation. Specifically, the coherent enhancement attribute value corresponding to the reservoir top location in the well logging interpretation is set as the threshold. For this work area, the threshold is 0.5. Coherent enhancement attribute values ​​greater than this threshold are not displayed, while values ​​less than or equal to this threshold are displayed. The displayed coherent enhancement attribute values ​​are as follows: Figure 2 The superimposed shaded area is shown on the original seismic profile of Zhongguojing.

[0063] See Figure 4 , Figure 4 This diagram displays the fractured-vuggy reservoir and its boundary extent. All coherence enhancement attribute values ​​less than or equal to a threshold are defined as 1, representing the fractured-vuggy reservoir; values ​​greater than the threshold are defined as 0, representing the surrounding rock. This results in the diagram of the fractured-vuggy reservoir and its boundary extent. Figure 4 As shown.

[0064] See Figure 5 , Figure 5 This is a surface view of the P-wave impedance distribution of the cavernous reservoir and surrounding rock. As can be seen from the figure, the P-wave impedance values ​​of the cavernous reservoir and surrounding rock differ. A value of 1.55e is used. 7 kg / m 3 *m / s is the threshold, greater than 1.55e 7 kg / m 3 *m / s is considered as surrounding rock, less than or equal to 1.55e 7 kg / m 3 *m / s is considered a cavernous reservoir.

[0065] Figure 6 Based on Figure 1 The deterministic inversion result obtained by performing deterministic inversion on the original seismic data.

[0066] Figure 7 This refers to a cavernous reservoir sculpted based on deterministic inversion results. Figure 5 The threshold obtained from Nakaoue's analysis is 1.55e. 7 kg / m 3 *m / s is used to sculpt the deterministic inversion result volume, where the deterministic inversion result value is less than or equal to 1.55e. 7 kg / m 3 *m / s is defined as 1, representing a cavernous reservoir, greater than 1.55e. 7 kg / m 3 *m / s is defined as 0, representing the surrounding rock, such as Figure 7 As shown.

[0067] Figure 8 This is the final map showing the fracture-void type reservoir and its distribution range. Figure 4 The fractured-vuggy reservoir obtained from the subtraction Figure 6 The cave-type reservoir obtained through deterministic inversion is sculpted, with a value of 1 representing a fracture-pore type reservoir and a value of 0 representing the surrounding rock. This yields the final fracture-pore type reservoir and its distribution range. Figure 8 As shown. This concludes the detailed classification of fractured-vuggy reservoirs.

[0068] Figure 9For fractured-void reservoirs obtained by combining seismic inversion results with well logging rock physics analysis, due to the relatively dense nature of fractured-void reservoirs and the high degree of overlap between the P-wave impedance values ​​of the fractured-void reservoir and the surrounding rock, the interpretation of fractured-void reservoirs obtained by conventional inversion results through well logging rock physics analysis is not accurate. Some surrounding rocks are interpreted as fractured-void reservoirs, and a very small portion are interpreted as cavernous reservoirs, such as... Figure 9 As shown in the dashed box. By comparison, the boundary of the fracture-vuggy reservoir in this invention is determined based on coherent enhancement properties combined with actual engineering anomalies such as venting and leakage. The fracture-vuggy reservoir and its distribution range are obtained on this basis. The obtained fracture-vuggy reservoir and its distribution range are more accurate and reliable. At the same time, this invention also greatly reduces the probability of identifying the surrounding rock as a reservoir, and the surrounding rock background is also cleaner, which is more in line with geological understanding.

[0069] This invention utilizes well logging interpretation of the reservoir top location to calibrate the coherent enhancement attribute volume. Specifically, the coherent enhancement attribute value corresponding to the reservoir top location interpreted by well logging is set as a threshold. Values ​​greater than this threshold are defined as 0, representing surrounding rock; values ​​less than or equal to the threshold are defined as 1, representing fractured-vuggy reservoirs. This process yields the fractured-vuggy reservoir and its boundary range, enabling boundary identification of fractured-vuggy reservoirs. Because it fully references actual well logging data based on coherent enhancement attributes, the boundary identification results for fractured-vuggy reservoirs are relatively reliable.

[0070] This invention selects wells in the work area that encounter cave-type reservoirs for logging rock physics analysis to determine the P-wave impedance boundary value between the cave-type reservoir and the surrounding rock. The boundary value is then used to refine the post-stack deterministic inversion results. Deterministic inversion result values ​​greater than the boundary value are defined as 0, representing the surrounding rock, and values ​​less than or equal to the boundary value are defined as 1, representing the cave-type reservoir. This process yields the cave-type reservoir and its boundary range. The method and workflow are used to determine the cave-type reservoir and its boundary.

[0071] Carbonate fracture-vuggy reservoirs can be broadly classified into cavernous and fracture-void reservoirs. Therefore, subtracting the cavernous reservoir from the predicted fracture-vuggy reservoir yields a value of 1 representing a fracture-void reservoir and 0 representing the surrounding rock, thus obtaining the fracture-void reservoir and its boundary range. This method indirectly yields the fracture-void reservoir and its boundary range, achieving further accurate prediction of fracture-void reservoirs within the sub-categories of carbonate fracture-vuggy reservoirs. It overcomes the inaccuracy of conventional seismic inversion combined with well logging petrophysical analysis in characterizing fracture-void reservoirs, achieving further accurate prediction of fracture-void reservoirs within the sub-categories of fracture-vuggy reservoirs.

[0072] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A refined reservoir prediction method for fractured-vuggy carbonate reservoirs, characterized in that, Includes the following steps: Step 1: Based on the original post-stack seismic data, perform coherent enhancement attribute analysis. Use well logging to interpret the reservoir top location to calibrate the coherent enhancement attribute. Use the coherent enhancement attribute value corresponding to the reservoir top location interpreted by well logging as a threshold. Based on the relationship between the coherent enhancement attribute value and the threshold, determine the predicted fracture-vuggy reservoir and its boundary. Post-stack deterministic inversion is performed on the original post-stack seismic data to obtain the boundary value of the P-wave impedance of the cavernous reservoir and the surrounding rock; the post-stack deterministic inversion results are then sculpted using the boundary value to obtain the predicted cavernous reservoir and its boundary. Step 2: Based on the predicted fracture-vuggy reservoir, remove the cavernous reservoir to obtain the fracture-vuggy reservoir and its boundary range; In step 1, the determination is made based on the relationship between the coherence enhancement attribute value and the threshold, specifically as follows: The coherent enhancement attribute value greater than the threshold is defined as 0, corresponding to the surrounding rock; all coherent enhancement attribute values ​​less than or equal to the threshold are defined as 1, corresponding to the fractured-vuggy reservoir, thus obtaining the fractured-vuggy reservoir and its boundary range. In step 1, the post-stack deterministic inversion results are sculpted using the aforementioned boundary values ​​to obtain the predicted cavernous reservoir and its boundary range, specifically as follows: A deterministic inversion result value greater than the threshold value is defined as 0, representing the surrounding rock; A deterministic inversion result value less than or equal to the boundary value is defined as 1, representing a cavernous reservoir, thus obtaining the cavernous reservoir and its boundary range; Step 2 is as follows: The definition value of fracture-vuggy reservoir is subtracted from the definition value of cavernous reservoir by the predicted definition value. If the difference is 1, it represents fracture-vuggy reservoir; if the difference is 0, it represents surrounding rock. This gives us the fracture-vuggy reservoir and its boundary.

2. The refined reservoir prediction method for fractured-vuggy carbonate reservoirs according to claim 1, characterized in that, Step 1 involves obtaining the boundary value between the P-wave impedance of the cavernous reservoir and the surrounding rock, specifically as follows: Well logging rock physics analysis was performed on wells that encountered cave-type reservoirs in the work area to obtain the P-wave impedance distribution map of the cave-type reservoir and the surrounding rock, and then the boundary value of the P-wave impedance between the cave-type reservoir and the surrounding rock was determined.

3. The refined reservoir prediction method for fractured-vuggy carbonate reservoirs according to claim 1, characterized in that, The longitudinal wave impedance of the cavernous reservoir and the surrounding rock in step 1 is taken from the same well that encountered the cavernous reservoir.

4. A fine reservoir prediction device for carbonate fracture-vuggy reservoirs implementing the method of claim 1, characterized in that, Includes modules for predicting fractured-vuggy and cavernous reservoirs and modules for predicting fractured-vuggy reservoirs; The fractured-vuggy and cavernous reservoir prediction module is used to generate coherent enhancement attributes based on the original post-stack seismic data, use well logging to interpret the reservoir top position to calibrate the coherent enhancement attribute volume, use the coherent enhancement attribute value corresponding to the well logging interpreted reservoir top position as a threshold, and make a judgment based on the relationship between the coherent enhancement attribute value and the threshold to obtain the fractured-vuggy reservoir and its boundary. It is also used to perform post-stack deterministic inversion on the original post-stack seismic data and obtain the boundary value of the P-wave impedance of the cavernous reservoir and the surrounding rock; the boundary value is used to sculpt the post-stack deterministic inversion results to obtain the cavernous reservoir and its boundary. The fracture-void reservoir prediction module is used to remove cavernous reservoirs based on the predicted fracture-void reservoirs, thereby obtaining the fracture-void reservoirs and their boundary ranges.

5. The fine reservoir prediction device for carbonate fracture-vuggy reservoirs according to claim 4, characterized in that, The fractured-vuggy and cavernous reservoir prediction module includes a fractured-vuggy reservoir prediction unit and a cavernous reservoir prediction unit; The fractured-vuggy reservoir prediction unit is used to generate coherent enhancement attributes based on the original post-stack seismic data. The coherent enhancement attribute volume is calibrated by interpreting the reservoir top position using well logging. The coherent enhancement attribute value corresponding to the reservoir top position interpreted by well logging is used as a threshold. The relationship between the coherent enhancement attribute value and the threshold is used to determine the fractured-vuggy reservoir and its boundary. The cavernous reservoir prediction unit is used to perform post-stack deterministic inversion on the original post-stack seismic data and obtain the boundary value of the P-wave impedance between the cavernous reservoir and the surrounding rock; the boundary value is used to sculpt the post-stack deterministic inversion results to obtain the cavernous reservoir and its boundary.

6. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the fine reservoir prediction method for carbonate fracture-vuggy reservoirs as described in any one of claims 1-3.

7. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the fine reservoir prediction method for fractured-vuggy carbonate reservoirs as described in any one of claims 1-3.

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