Earthquake-engineering-well testing and dynamic parameter association method and application

Abstract

The invention discloses an earthquake-engineering-well testing and dynamic parameter association method and application, and belongs to the technical field of oil and gas development. The association method comprises the following steps: determining dynamic parameters to be associated; collecting the existing dynamic characteristics of the production well similar to the dynamic parameters to be associated and the existing data of the production well; analyzing the dynamic parameter physical property response lower limit of the collected existing dynamic parameters in the corresponding existing data; deleting a physical property response lower limit part in the existing data corresponding to the existing dynamic parameters, and performing statistical analysis to obtain an association result of the to-be-associated dynamic parameters and earthquake-engineering-well testing; compared with the prior art, the method can effectively predict the production dynamics according to the seismic interpretation result of the production well, the drilling and acid fracturing engineering process response parameters and the well testing interpretation result, and provides a theoretical basis for matching engineering parameters and dynamic prediction before drilling of the fractured-vuggy reservoir.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil and gas development, and particularly relates to a method for correlating seismic-engineering-well testing with dynamic parameters and an application thereof. Background Art

[0002] Fractured-vuggy reservoirs have complex pore structures, various fracture-vug connection forms, and various flow mechanisms. Moreover, the reservoirs have extremely strong heterogeneity and anisotropy. The research on fractured-vuggy reservoirs has become the focus of current oil and gas reservoir development. Before drilling, if the dynamic characteristics of production wells can be predicted through the matching of geological characteristics and engineering parameters, it is of great significance for the planning of oil and gas reservoir development; therefore, how to achieve the correlation between seismic-engineering-well testing and dynamic parameters is very important.

[0003] Patent CN105718705B discloses a method for dynamic analysis of oil and gas fields. First, the next development plan is obtained through empirical analysis within the block, and then the plan is simulated and analyzed by combining theoretical analysis and mathematical models. If the analysis results of the mathematical model are the same as or similar to the results derived theoretically, the plan is adjusted; otherwise, the method of analogical analysis is adopted to find blocks with the same or similar properties for analogical analysis to obtain the final adjustment plan. This invention uses multiple dynamic analysis methods to complement and confirm each other, solves the problem of single dynamic analysis method in the prior art, and achieves the purpose of dynamically analyzing oil and gas fields through mutual confirmation of multiple methods.

[0004] However, for clastic oil and gas reservoirs, due to the good continuity of the reservoir, the production of production wells under different engineering conditions can be preliminarily predicted more accurately according to geological characteristics. But for fractured-vuggy oil and gas reservoirs, due to the huge differences in geological characteristics, the accuracy and reliability of the foregoing prediction methods are relatively poor; currently, the relationship between seismic interpretation results, engineering process parameters, well testing results, and production dynamics in fractured-vuggy oil and gas reservoirs is not clear, which forms an obstacle to the prediction of production dynamics and the formulation of construction plans. Therefore, it is difficult for the oil and gas field dynamic analysis method provided by the above-mentioned patent to achieve the analogical correlation between multiple parameters in fractured-vuggy oil and gas reservoirs.

[0005] In summary, how to provide a dynamic prediction method for fractured-vuggy reservoirs, which can roughly predict the dynamic characteristics of production wells through the understanding of geological characteristics and the matching of engineering parameters before production, is a problem that those skilled in the art expect to solve. Summary of the Invention

[0006] In view of the lack in the prior art of a method for roughly predicting the dynamic characteristics of production wells through understanding of geological features and matching of engineering parameters for fracture-vuggy reservoirs, the present invention provides a method for correlating seismic-engineering-well testing and dynamic parameters, so as to predict production dynamics based on the seismic interpretation results of production wells, the engineering process response parameters of drilling + acid fracturing, and the well testing interpretation results; and it can provide a theoretical basis for matching engineering parameters before drilling and dynamic prediction for fracture-vuggy reservoirs.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A method for correlating seismic-engineering-well testing and dynamic parameters includes the following steps:

[0009] S1. Determine the dynamic parameters to be correlated.

[0010] S2. Collect the existing dynamic characteristics of production wells of the same type as the dynamic parameters to be correlated in step S1, and the existing data of the production wells.

[0011] S3. Analyze the lower limit of the physical property response of the existing dynamic parameters in the existing data corresponding thereto collected in step S2.

[0012] S4. Delete the part of the lower limit of the physical property response in the existing data corresponding to the existing dynamic parameters in step S3, and statistical analysis can obtain the correlation result between the dynamic parameters to be correlated and seismic-engineering-well testing.

[0013] Preferably, the dynamic parameters to be correlated in step S1 are selected from elastic productivity, production decline rate, and open flow potential.

[0014] Preferably, the existing data of the production wells in step S2 include seismic interpretation results, engineering process response characteristics of drilling + acid fracturing, and well testing interpretation characteristics.

[0015] Preferably, the method for determining the lower limit of the physical property response of the dynamic parameters in step S3 includes the following steps:

[0016] (1) Fit the results of the existing dynamic parameters and their corresponding existing parameters in step S3 to form a curve.

[0017] (2) Determine the lower limit of the physical property response of the dynamic parameters according to the shape of the curve.

[0018] Further preferably, the dynamic parameters in step (1) are selected from elastic productivity, production decline rate, and open flow potential; and the existing data include seismic interpretation results, engineering process response characteristics of drilling + acid fracturing, and well testing interpretation characteristics.

[0019] Preferably, the method of statistical analysis in step S4 includes: establishing a model and conducting digital simulation demonstration.

[0020] Further preferably, the model establishment adopts a hierarchical constraint modeling method.

[0021] Even more preferably, the hierarchical constraint modeling method includes the establishment of a fracture system model, a structural model, a reservoir profile model, an internal structure model, and a parameter model.

[0022] Most preferably, the numerical simulation demonstration includes drawing the variation relationship of the dynamic parameters to be correlated with one or several of the geological features, seismic interpretation results, drilling + acid fracturing engineering process response features, and well test interpretation features in the model.

[0023] The present invention also provides an application of the above correlation method in the exploitation of a fracture-vuggy reservoir.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention discloses a correlation method for seismic - engineering - well test and dynamic parameters, which solves the problem that the relationship between the dynamic characteristics of the current fracture - vuggy oil and gas reservoir, the seismic interpretation results, the engineering process response parameters of drilling + acid fracturing, and the well test interpretation results is unclear; the present invention can effectively predict the production dynamics according to the seismic interpretation results, the engineering process response parameters of drilling + acid fracturing, and the well test interpretation results of production wells, and provide a theoretical basis for pre - drilling matching of engineering parameters and dynamic prediction in fracture - vuggy reservoirs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a relationship diagram between the open - flow potential and the carved - body reserves of the first - type wells in the embodiments of the present invention;

[0027] Figure 2 It is a relationship diagram between the open - flow potential and the carved - body reserves of the second - type wells in the embodiments of the present invention;

[0028] Figure 3 It is a relationship diagram between the open - flow potential and the pump - shut - off pressure of the first - type wells in the embodiments of the present invention;

[0029] Figure 4 It is a relationship diagram between the open - flow potential and the pump - shut - off pressure of the second - type wells in the embodiments of the present invention;

[0030] Figure 5 It is a relationship diagram between the open - flow potential and the pump - shut - off curve of the first - type wells in the embodiments of the present invention;

[0031] Figure 6 It is a relationship diagram between the open - flow potential and the pump - shut - off curve of the second - type wells in the embodiments of the present invention;

[0032] Figure 7 It is a relationship diagram between the open - flow potential and the formation factor of the first - type wells in the embodiments of the present invention;

[0033] Figure 8 It is the relationship diagram between the open flow potential and the formation coefficient of the second type of well in the embodiment of the present invention;

[0034] Figure 9 It is the relationship diagram between the open flow potential and the carved body reserve digital simulation of Well SHB4-4H in the embodiment of the present invention;

[0035] Figure 10 It is the digital simulation relationship diagram between the open flow potential and the shut-in pressure of Well SHB4-4H in the embodiment of the present invention;

[0036] Figure 11 It is the digital simulation relationship diagram between the open flow potential and the characteristics of the shut-in curve of Well SHB4-4H in the embodiment of the present invention;

[0037] Figure 12 It is the digital simulation relationship diagram between the open flow potential and the formation coefficient of Well SHB4-4H in the embodiment of the present invention. Specific embodiments

[0038] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0039] Embodiment A method for correlating seismic-engineering-well testing and dynamic parameters

[0040] (1) Data collection

[0041] For the Shunbei No. 4 fault zone, the selected production dynamic parameter is the open flow potential. Analyze the open flow potential and establish relationships with seismic interpretation results, drilling + acid fracturing engineering process response characteristics, and well testing interpretation characteristics. The relationships between the open flow potential and the three response characteristics were studied and statistically analyzed. The statistical relationships are as follows. During the statistical process, according to the dynamic characteristics, the production wells were divided into two categories, and the statistical results of the two types of wells are presented below.

[0042] (2) Determination of the physical property response lower limit with seismic interpretation results

[0043] As Figure 1 it can be seen, for the first type of well, the relationship between the open flow potential and the carved body shows a positive correlation, with a good relationship. The larger the reserve, the larger the open flow potential. A large reserve indicates well-developed reservoir bodies, well-developed reservoir bodies indicate good flow conditions, and a large open flow potential. The first type of well does not require screening and has no physical property response lower limit.

[0044] As Figure 2 shown for the second type of well, the relationship between the open flow potential and the carved body reserve is not clear, or even shows a negative correlation. The physical property response lower limit of the open flow potential is set at 1.35 million cubic meters per day.

[0045] (3) Determination of the physical property response lower limit with drilling + engineering response

[0046] As Figure 3 can be seen, the relationship between the open flow potential and the shut-in pressure of the first type of wells shows a negative correlation, with a good relationship. The lower the shut-in pressure, the better the flow condition of the reservoir body, and the greater the open flow potential. For the first type of wells, 1.1 million m³ / day can be determined as the response lower limit.

[0047] For the second type of wells, as Figure 4 shown, the relationship between the open flow potential and the shut-in pressure is not clear, and the response lower limit can be not considered.

[0048] As Figure 5 can be seen, the relationship between the open flow potential and the shut-in pressure curve of the first type of wells shows a negative correlation, with a good relationship. The shut-in pressure curve 1 = close to straight, which is a cave; 2 = uniformly decreasing, which is a fracture; 3 = rapidly decreasing, which is a pore. Here, it shows that the shut-in characteristics of the first type of wells can be used to judge the open flow potential.

[0049] However, for the second type of wells as Figure 6 shown, although most of the shut-in pressure curves are of type 1, mainly caves, the relationship between the shut-in pressure curve and the open flow potential is not clear. The response lower limit of the first type of wells can be determined as 1.1 million m³ / day. There is no correlation for the second type of wells.

[0050] (4) Determination of the physical property response lower limit from well test interpretation results

[0051] As Figure 7 can be seen, the relationship between the formation coefficient and the open flow potential is clear. The larger the formation coefficient, the greater the flow capacity and the higher the productivity of the formation. However, it is not a linear relationship, but there is a trend that the amplitude slows down during the rising process. This is because when the formation coefficient is higher than a certain value, roughly after 15000 mD·m. Therefore, the response lower limit of the first type of wells can be determined as 1.1 million m³ / day.

[0052] Figure 8 The data relationship in

[0053] (5) Determination of the numerical simulation relationship

[0054] Further starting from the numerical reservoir model established on site, a gas reservoir mechanism model for the on-site development wells is established to verify the development law of the single fracture mechanism model. Based on the development characteristics of the reservoir body of the ultra-deep fault-karst reservoir, the results of the fracture system, reservoir outline, reservoir body identification and description, comprehensive use of data from aspects such as seismic, logging, geology, and production dynamics, and adopting the method of hierarchical constraint modeling, a fracture system model, a structural model, a reservoir outline model, an internal structure model, and a parameter model are established respectively, and different types of reservoir bodies are integrated into a three-dimensional geological model of the ultra-deep fault-karst reservoir.

[0055] Well SHB4-4H to be analyzed is located in the pull-apart fault zone of the main fault in Zone 2 of the Shunbei Oilfield. The actual deep well trajectory in the mountain penetrates the bead-shaped reflectors, showing good reservoir space. The model depth is 6277.0 - 7873.2 m, the average grid size is 50 m × 50 m × 2 m, and the number of grids is 45520. Due to the influence of integrated geology and engineering, the component model of condensate gas is not fully adopted, but an equivalent black oil dry gas model. The geological reserves of natural gas in the gas reservoir model are set at 722 million cubic meters.

[0056] When the production well is directly drilled on the main fracture, the research adopted a pumping rate of 15 m 3 / min and a construction scale of a total of 3000 cubic meters of liquid volume. 500 cubic meters of acid fluid was used as the basic data for simulating the fracture propagation during the acid fracturing process. The simulation results under the basic parameters show that the fracture pressure ignores the direction of the minimum principal stress and the magnitude of the stress difference and directly extends along the fracture.

[0057] And the formation in this simulation belongs to ultra-deep formation (>6000 m), and only the experimental data with the highest and closest temperature and pressure conditions can be selected. Therefore, for the rock mechanics parameters, the experimental data of the sample with a confining pressure of 60 MPa and a temperature of 140 °C from Well Shunbei Ping 2H were selected. The average value of the selected sample data was taken as the rock mechanics parameters of the formation near the fracture zone. The Young's modulus of the formation near the fracture was 58 GPa, and the Poisson's ratio was 0.287. The auxiliary model can be regarded as a geological body from the surface to 9000 m underground, and the overall temperature and pressure conditions are lower than those of the ultra-deep formation. The interior of the fracture zone is mainly composed of fault gouge and breccia. Since it is difficult to obtain samples for mechanical parameter experiments and considering that its rock strength should be relatively low, the rock mechanics parameters of mudstone were referred to in this simulation. Finally, the Young's modulus inside the fracture zone was determined to be 10 GPa, and the Poisson's ratio was 0.35. Among them, the reservoir temperature was set at 170 °C, 10% HCL was used for acid fracturing, and the software-built-in parameters were used for the acid-rock reaction.

[0058] Among them, SHB4-4H is the first type of well in steps (2)-(4) of the embodiment. Combining the study of the lower limit of physical property response deletion, the relationship between the open flow potential, the carved body reserves, the shut-in pressure, the characteristics of the shut-in curve, and the formation coefficient under different fracture extension conditions is as Figures 9 - 12 shown, so as to realize the correlation between dynamic parameters and seismic-engineering-well testing.

[0059] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than to limit the protection scope of the present invention. Any simple modification or equivalent replacement of the technical solution of the present invention by those of ordinary skill in the art shall not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A method for correlating seismic - engineering - well testing with dynamic parameters, characterized in that It includes the following steps: S1. Determine the dynamic parameters to be correlated; S2. Collect the existing dynamic characteristics of production wells that are of the same type as the dynamic parameters to be correlated described in step S1, as well as the existing data of production wells; S3. Analyze the lower limit of the physical property response of the existing dynamic parameters collected in step S2 in their corresponding existing data; S4. Delete the part of the lower limit of the physical property response in the existing data corresponding to the existing dynamic parameters in step S3, and through statistical analysis, the correlation result between the dynamic parameters to be correlated and seismic-engineering-well testing can be obtained.

2. The association method according to claim 1, wherein The dynamic parameters to be correlated described in step S1 include elastic production rate, production decline rate, and open flow potential.

3. The association method according to claim 1, wherein The existing data of the production wells described in step S2 include seismic interpretation results, response characteristics of the drilling + acid fracturing engineering process, and well testing interpretation characteristics.

4. The association method according to claim 1, characterized in that, The method for determining the lower limit of the physical property response of the dynamic parameters described in step S3 includes the following steps: (1) Fit the results of the existing dynamic parameters described in step S3 and their corresponding existing parameters to form a curve; (2) Determine the lower limit of the physical property response of the dynamic parameters according to the shape of the curve.

5. The association method according to claim 4, wherein The dynamic parameters described in step (1) are selected from elastic production rate, production decline rate, and open flow potential; the existing data include seismic interpretation results, response characteristics of the drilling + acid fracturing engineering process, and well testing interpretation characteristics.

6. The association method according to claim 1, wherein The method of statistical analysis described in step S4 includes: establishing a model and conducting digital simulation demonstration.

7. The association method according to claim 6, characterized in that The model establishment adopts the hierarchical constraint modeling method.

8. The association method according to claim 7, wherein The hierarchical constraint modeling method includes the establishment of a fracture system model, a structural model, a reservoir contour model, an internal structure model, and a parameter model.

9. The association method according to claim 8, wherein The digital simulation demonstration includes plotting the variation relationship between the dynamic parameters to be correlated in the model and one or several of the geological characteristics, seismic interpretation results, response characteristics of the drilling + acid fracturing engineering process, and well testing interpretation characteristics.

10. Application of the correlation method according to any one of claims 1-9 in the exploitation of fractured-vuggy reservoirs.

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