A modeling method and device for connecting channels between oil reservoir wells, and storage medium

Abstract

The present invention discloses a modeling method and device for an inter-well communication channel in an oil reservoir, and a storage medium. The method comprises: constructing an initial inter-well communication channel according to cave data and / or fracture data between target well groups; calculating the amount of simulated produced tracer according to the initial inter-well communication channel and inter-well tracer experimental data; judging whether the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer is greater than or equal to a preset threshold value: if so, outputting the initial inter-well communication channel; if not, adjusting the cave data and / or fracture data between the target well groups to optimize the inter-well communication channel until the degree of agreement corresponding to the optimized inter-well communication channel is greater than or equal to the preset threshold value, so that the communication channel represented on the computer is not only consistent with the static geological data, but also consistent with the characteristic dynamic data, thereby improving the accuracy of the communication channel and providing a reliable basis for subsequent adjustment of the oil reservoir development plan.

Description

Technical Field

[0001] The invention belongs to the technical field of oil reservoir fine characterization application, and in particular relates to a modeling method and device for an inter-well communication channel in an oil reservoir, and a storage medium. Background Art

[0002] In the development and production of fracture-cavity reservoirs, the dynamic connectivity of the reservoir is the basic production unit of the oil field, among which the main dynamic connectivity is the caves and fractures of different sizes (Yang Yu, Kang Yili, Zhang Fengdong, et al. Definition and division of flow units of fracture-cavity reservoirs in Tahe Oilfield [J]. Daqing Petroleum Geology and Development, 2007, 26(002): 31-33.). Using geostatistics and other methods and related reservoir geological theories to achieve a true and accurate characterization of the dynamic connectivity of fracture-cavity reservoirs is an important prerequisite for the successful subsequent numerical simulation, history fitting and development prediction of the reservoir (Yang Jian, Cheng Qian, Li Jianglong, et al. Inter-well connectivity of fracture-cavity reservoirs in Tahe District 4, Tarim Basin [J]. Petroleum and Natural Gas Geology, 2012(03): 484-489.).

[0003] The most widely used methods for characterizing reservoir connectivity are to start with static geological data, and to make the characterized reservoir connectivity consistent with static geological data such as seismic data and wellbore data as much as possible through reservoir and geological analysis, mathematical computer algorithms (such as multi-point geostatistics), etc. (Hou Jiagen, Ma Xiaoqiang, Liu Yuming, Zhao Bin. Research on multi-class and multi-scale modeling methods for fracture-cavity carbonate reservoirs: A case study of Ordovician reservoirs in the fourth block of Tahe Oilfield [J]. Earth Science Frontiers, 2012, 19(02): 59-66.). However, in addition to static geological data such as seismic data, there are more dynamic data for reservoir characterization, such as injection and production fluid data, interference well test data, and liquid marker detection data. These reservoir dynamic data can truly and reliably reflect the geological and reservoir properties of underground reservoir connectivity, and are of great value in the characterization of reservoir connectivity. However, the above traditional methods cannot integrate these characteristic dynamic data, resulting in inconsistency between the characterized reservoir connectivity and the dynamic data, and even great contradictions. This contradiction can be manifested as follows: (1) For example, the characteristic production dynamic data show that A, B and C are a unified reservoir interconnected body and can be developed together, but the represented reservoir connectivity model only shows that A and B are a unified reservoir interconnected body and C is an isolated interconnected body; (2) The characteristic production dynamic data show that A, B and C are three isolated interconnected bodies, but the represented connectivity model shows that the three are a unified reservoir interconnected body; (3) The dynamic data show that A and B are a unified reservoir interconnected body, and the represented connectivity model also shows that the two are a unified reservoir interconnected body, but the connectivity characteristics between the two in the connectivity model are quite different from the actual characteristic dynamic data.

[0004] In actual industrial practice, in order to solve this problem, engineers often manually adjust the characterized reservoir connectivity, such as modifying the density of fractures in some parts or increasing the number of small caves, etc. However, this subjective and empirical approach is not only extremely time-consuming and labor-intensive, but also cannot guarantee that the connectivity characteristics of the manually modified reservoir connectivity are consistent with the actual characteristic production data, affecting subsequent history matching and well location design.

[0005] There is an urgent need for a modeling method, device and storage medium for inter-well communication channels in oil reservoirs. Summary of the invention

[0006] The technical problem to be solved by the present invention is how to accurately determine the inter-well communication channels in the oil reservoir, so as to provide a reliable basis for subsequent numerical simulation, adjustment of the oil reservoir development plan and evaluation of injection and production effects.

[0007] In view of the above problems, the present invention provides a modeling method and device, and a storage medium for a communication channel between oil reservoir wells.

[0008] In a first aspect, the present invention provides a method for modeling a communication channel between wells in an oil reservoir, comprising the following steps:

[0009] S100, constructing an initial well-to-well communication channel according to cave data and / or fracture data between target well groups;

[0010] S200, calculating the amount of simulated produced tracer according to the initial inter-well communication channel and inter-well tracer experimental data;

[0011] S300, collecting the actual amount of produced tracer, and calculating the degree of agreement between the simulated amount of produced tracer and the actual amount of produced tracer;

[0012] S400, optimizing the initial inter-well communication channel according to the degree of agreement between the simulated amount of produced tracer and the actual amount of produced tracer to obtain an optimized inter-well communication channel as the determined inter-well communication channel.

[0013] According to an embodiment of the present invention, preferably, step S400 includes the following steps:

[0014] S410, determining whether the consistency between the simulated amount of the produced tracer and the actual amount of the produced tracer is greater than or equal to a preset threshold:

[0015] S420, when the degree of agreement between the simulated amount of produced tracer and the actual amount of produced tracer is greater than or equal to a preset threshold, the initial inter-well communication channel is used as the determined inter-well communication channel;

[0016] S430, when the degree of agreement between the simulated amount of produced tracer and the actual amount of produced tracer is less than a preset threshold, adjust the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups to obtain an optimized well-to-well communication channel, and use the optimized well-to-well communication channel as the initial well-to-well communication channel, and return to step S200.

[0017] According to an embodiment of the present invention, preferably, step S400 includes the following steps:

[0018] S410, determining whether the consistency between the simulated amount of the produced tracer and the actual amount of the produced tracer is greater than or equal to a preset threshold:

[0019] S420, when the degree of agreement between the simulated amount of produced tracer and the actual amount of produced tracer is greater than or equal to a preset threshold, the initial inter-well communication channel is used as the determined inter-well communication channel;

[0020] S430, when the degree of agreement between the simulated amount of the produced tracer and the actual amount of the produced tracer is less than a preset threshold, executing step S440;

[0021] S440, adjusting the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups to obtain an optimized well-to-well communication channel;

[0022] S450, calculating the degree of agreement between the amount of simulated produced tracer corresponding to the optimized inter-well communication channel and the amount of actual produced tracer, and comparing it with the degree of agreement corresponding to the inter-well communication channel before optimization;

[0023] S460, when the degree of fit corresponding to the optimized inter-well communication channel is greater than the degree of fit corresponding to the inter-well communication channel before optimization, comparing the degree of fit corresponding to the optimized inter-well communication channel with a preset threshold;

[0024] S470, when the degree of fit corresponding to the optimized inter-well communication channel is greater than or equal to a preset threshold, the optimized inter-well communication channel is used as the determined inter-well communication channel;

[0025] S480, when the degree of fit corresponding to the optimized inter-well communication channel is less than a preset threshold, return to step 440 to optimize the inter-well communication channel again;

[0026] S490, when the degree of fit corresponding to the optimized inter-well communication channel is less than or equal to the degree of fit corresponding to the inter-well communication channel before optimization, return to step 440 to optimize the inter-well communication channel again.

[0027] According to an embodiment of the present invention, preferably, before constructing the initial well-to-well communication channel according to the cave data and / or fracture data between the target well groups, the method further includes the following steps:

[0028] According to the shape of the concentration curve of the real produced tracer between the target well groups, it is judged whether the inter-well communication channel is constructed by caves, fractures, or caves and fractures at the same time;

[0029] The cave data and / or fracture data used to construct the inter-well communication channel are screened according to the judgment result.

[0030] According to an embodiment of the present invention, preferably, screening the cave data and / or fracture data for constructing the inter-well communication channel according to the judgment result includes the following steps:

[0031] When the inter-well communication channel is constructed by a cave, pipeline-type cave data is selected as cave data for constructing the inter-well communication channel;

[0032] When the inter-well communication channel is constructed by fractures, the fracture data used for constructing the inter-well communication channel are selected from the fractures identified by the ant body based on the fracture credibility;

[0033] When the inter-well communication channel is constructed by caves and fractures, pipeline-type cave data is selected as cave data for constructing the inter-well communication channel, and fracture data for constructing the inter-well communication channel is selected from the fractures identified by the ant body based on the fracture credibility.

[0034] According to an embodiment of the present invention, preferably, when the inter-well communication channel is constructed by fractures, constructing the initial inter-well communication channel according to the cave data and / or fracture data between the target well groups includes the following steps:

[0035] According to the fusion of different types of fractures, a discrete fracture three-dimensional spatial distribution model is formed as the initial well-to-well communication channel;

[0036] Adjusting the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups includes the following steps:

[0037] The orientation data in the fracture data in the discrete fracture three-dimensional spatial distribution model is adjusted to optimize the initial inter-well communication channel until the degree of fit corresponding to the optimized inter-well communication channel is greater than or equal to a preset threshold.

[0038] According to an embodiment of the present invention, preferably, when the inter-well communication channel is constructed by a cave or by a cave and a fracture, adjusting the attribute data in the cave data between the target well groups includes the following steps:

[0039] For two adjacent unconnected pipeline-type caves in the initial inter-well communication channel, determining a trend line for connecting the two adjacent unconnected pipeline-type caves according to the water flow direction in the pipeline-type cave;

[0040] Taking the vertical development probability of the pipeline-type cave as a constraint condition, the geometric statistical parameters of the trend line are adjusted.

[0041] According to an embodiment of the present invention, preferably, the geometric statistical parameters include wavelength, amplitude height, width and thickness, and the vertical development probability of the pipeline-type cave is used as a constraint condition to adjust the geometric statistical parameters of the trend line, including the following steps:

[0042] The trend line is divided into two parts: one end point a of the trend line and the karst cave segment disconnected from point a, and the other end point b of the trend line and the karst cave segment disconnected from point b;

[0043] Taking point a and point b as source points respectively, under the control of the trend line, setting the wavelength, amplitude height, width and thickness of the cave section disconnected from point a and the cave section disconnected from point b respectively, and taking the vertical development probability of the pipeline-type cave as a constraint condition, optimizing and simulating the cave section disconnected from point a and the cave section disconnected from point b;

[0044] The karst cave segment disconnected from point a and the karst cave segment disconnected from point b after the optimized simulation are overlapped, and the intersection is taken to obtain a pipeline-type cave used to connect the two adjacent unconnected pipeline-type caves, so that the two adjacent unconnected pipeline-type caves are in a connected state.

[0045] In a second aspect, the present invention provides a modeling device for a communication channel between oil reservoir wells, comprising:

[0046] A construction module, used to construct an initial well-to-well communication channel according to cave data and / or fracture data between target well groups;

[0047] A calculation module, used for calculating the amount of simulated produced tracer according to the initial inter-well communication channel and inter-well tracer experimental data;

[0048] The judgment module is used to judge whether the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer is greater than or equal to a preset threshold: when the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer is greater than or equal to the preset threshold, the initial inter-well communication channel is used as the determined inter-well communication channel; when the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer is less than the preset threshold, the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups are adjusted to optimize the inter-well communication channel until the degree of agreement corresponding to the optimized inter-well communication channel is greater than or equal to the preset threshold.

[0049] In a third aspect, the present invention provides a storage medium having a computer program stored thereon, which implements the steps of the above method when executed by a processor.

[0050] In a fourth aspect, the present invention provides a modeling device for inter-well communication channels in oil reservoirs, which includes a memory and a processor, wherein a computer program is stored in the memory, and the computer program implements the steps of the above method when executed by the processor.

[0051] Compared with the prior art, one or more embodiments of the above scheme may have the following advantages or beneficial effects:

[0052] The modeling method of the inter-well communication channel of the oil reservoir of the present invention is applied to construct an initial inter-well communication channel according to the cave data and / or fracture data between the target well groups; the amount of simulated produced tracer is calculated according to the initial inter-well communication channel and the inter-well tracer experimental data; the amount of real produced tracer is collected, and the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer is calculated; the initial inter-well communication channel is optimized according to the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer to obtain the optimized inter-well communication channel as the determined inter-well communication channel, so that the dynamic communication channel of the oil reservoir characterized on the computer is consistent with not only the static geological data, but also the characteristic dynamic data, thereby improving the accuracy of the description of the dynamic communication channel of the oil reservoir and providing a reliable basis for subsequent numerical simulation, adjustment of the oil reservoir development plan and evaluation of injection and production effects.

[0053] 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

[0054] 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:

[0055] Figure 1 A flow chart showing a method for modeling a well-to-well communication channel in an oil reservoir according to an embodiment of the present invention;

[0056] Figure 2a A schematic diagram of a single fracture well-to-well communication channel in Embodiment 1 of the present invention is shown;

[0057] Figure 2b A schematic diagram showing the tracer production form in a single fracture inter-well communication channel in Example 1 of the present invention is shown;

[0058] Figure 3a A schematic diagram of a plurality of fracture well-to-well communication channels in the first embodiment of the present invention is shown;

[0059] Figure 3b A schematic diagram showing the tracer production morphology in multiple fracture well-to-well communication channels in Example 1 of the present invention is shown;

[0060] Figure 4a A schematic diagram of a single cave well-to-well communication channel in Embodiment 1 of the present invention is shown;

[0061] Figure 4b A schematic diagram of the tracer production form in a single cave inter-well communication channel in Example 1 of the present invention is shown;

[0062] Figure 5a A schematic diagram of a plurality of inter-cavern well communication channels in the first embodiment of the present invention is shown;

[0063] Figure 5b A schematic diagram showing the tracer production form in multiple cave well-to-well communication channels in Example 1 of the present invention is shown;

[0064] Figure 6a A schematic diagram of an inter-well communication channel of a composite cave and fracture in the first embodiment of the present invention is shown;

[0065] Figure 6b A schematic diagram showing the tracer production form in the well-to-well communication channel with a combination of caves and fractures in Example 1 of the present invention is shown;

[0066] Figure 7 A schematic diagram showing a situation in which there are no fractures connecting the injection and production well groups in the three-dimensional geological model in the first embodiment of the present invention;

[0067] Figure 8 A multi-scale fracture modeling flow chart in Embodiment 1 of the present invention is shown;

[0068] Fig. 9 A schematic diagram of a discrete fracture network of a structural fracture in layer A in the first embodiment of the present invention is shown;

[0069] Fig.10 A schematic diagram of a discrete fracture network of a dissolution fracture in layer A in Example 1 of the present invention is shown;

[0070] Fig.11 A flow chart showing a method for modeling a communication channel between oil reservoir wells according to a second embodiment of the present invention;

[0071] Fig.12a A schematic diagram of crack azimuth transformation in the second embodiment of the present invention is shown;

[0072] Figure 12b A schematic diagram showing the classification of cracks according to the crack azimuth in the second embodiment of the present invention is shown;

[0073] Fig.13 A schematic diagram of the crack movement process in the second embodiment of the present invention is shown;

[0074] Fig.14 A schematic diagram showing the derivation of the ordinate when the perforation depths of two wells are inconsistent in the second embodiment of the present invention is shown;

[0075] Fig.15a A schematic diagram showing a connecting channel before construction in application scenario 1 of embodiment 2 of the present invention;

[0076] Fig.15b A schematic diagram showing the construction of a connecting channel in application scenario 1 of embodiment 2 of the present invention is shown;

[0077] Fig.16 A curve diagram of the yield of liquid marker and real liquid marker in application scenario 1 of embodiment 2 of the present invention is shown;

[0078] Fig.17 A schematic diagram of the internal communication channel of the reservoir communication body constructed in the second application scenario of the second embodiment of the present invention is shown.

[0079] Fig.18 A schematic diagram showing the connection process of two adjacent caves in the third embodiment of the present invention is shown;

[0080] Fig.19 The vertical development probability of the river channel in the third embodiment of the present invention is shown. DETAILED DESCRIPTION

[0081] 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.

[0082] Embodiment 1

[0083] In order to solve the above technical problems existing in the prior art, an embodiment of the present invention provides a modeling method for inter-well communication channels in an oil reservoir.

[0084] Reference Figure 1 The modeling method of the inter-well communication channel of the oil reservoir of this embodiment includes the following steps:

[0085] S110, judging whether the inter-well communication channel is constructed by caves, fractures, or both caves and fractures according to the shape of the concentration curve of the actual produced tracer between the target well groups;

[0086] S120, screening the cave data and / or fracture data used for constructing the inter-well communication channel according to the judgment result;

[0087] S130, constructing an initial well-to-well communication channel according to the cave data and / or fracture data between the target well groups;

[0088] S140, calculating the amount of simulated produced tracer according to the initial inter-well communication channel and inter-well tracer experimental data;

[0089] S150, determining whether the degree of agreement between the simulated amount of the produced tracer and the actual amount of the produced tracer is greater than or equal to a preset threshold:

[0090] If yes, execute step S160;

[0091] If not, execute step S170;

[0092] S160, using the initial inter-well communication channel as the determined inter-well communication channel;

[0093] S170, adjusting the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups to obtain an optimized inter-well communication channel, and using the optimized inter-well communication channel as the initial inter-well communication channel, and returning to step S140.

[0094] In step S110, it is determined whether the inter-well communication channel is constructed by caves, fractures, or caves and fractures at the same time according to the shape of the concentration curve of the actual produced tracer between the target well groups. The specific implementation process is as follows:

[0095] Tracers have become one of the most commonly used technical means to analyze the types of underground well-to-well communication channels and determine the spatial characteristics of karst reservoirs. The basic principle is to first collect the static and dynamic data of the injection well group, and select the appropriate tracer indoors; then design a monitoring plan, add tracers to the test well group, and sample and test the tracer content in the corresponding oil wells according to the established sampling system; finally, draw the tracer production curve of the corresponding oil well, and obtain the movement direction, circulation characteristics, advancement speed, sweep situation and other reservoir information of the injected fluid of the test well group through comprehensive analysis of the tracer production curve and static and dynamic data of the test well group.

[0096] The type of connected channel can be determined by using the changing characteristics of the tracer concentration curve. Theoretically, the curve of the change of concentration over time in a single channel shows a peak shape. According to the shape of the peak (sharp peak or wide peak), it can be judged whether the connected channel belongs to a cave or a fracture. If the wells are connected through a single cave, the tracer will be diluted by the underground river, which will appear as a wide peak on the concentration time curve; if they are connected through a single dissolution fracture, it will appear as a sharp peak on the curve; if the observed curve is a multi-peak curve, it means that there are multiple underground rivers or fractures between the two wells. The number of peaks can be used to analyze the number of connected channels, among which Table 1 shows the model of the type of connected channels and the tracer response characteristics. The reason for the peak is that the morphology, scale, and internal filling characteristics of different connected channels are different, the speed and time of the tracer migration in the channel are different, and the time to reach the outlet is different.

[0097] Table 1

[0098]

[0099] In step S120, the cave data and / or fracture data used to construct the inter-well communication channel are screened according to the judgment result, including the following steps:

[0100] S121, when the inter-well communication channel is constructed by a cave, selecting pipeline-type cave data as cave data for constructing the inter-well communication channel;

[0101] S122, when the inter-well communication channel is constructed by fractures, selecting fracture data for constructing the inter-well communication channel from the fractures identified by the ant body based on the fracture credibility;

[0102] S123, when the inter-well communication channel is constructed by caves and fractures, filter the pipeline-type cave data as the cave data for constructing the inter-well communication channel, and filter the fracture data for constructing the inter-well communication channel from the fractures identified by the ant body based on the fracture credibility.

[0103] In step S122, when screening fractures, for the reservoirs connected by fractures, in the three-dimensional geological model established based on static data, there may be local inconsistencies between the well connectivity and the well dynamic data, such as Figure 7As shown in the figure, there are no fractures connecting the injection and production well groups in the 3D geological model, while the actual tracer test shows that the well groups have good connectivity. The well spacing of this well group is more than a kilometer, and it cannot be connected through small-scale fractures; the well connectivity in the model is inconsistent with the tracer monitoring data. This is mainly due to the randomness of fracture modeling. The established DFN fracture model has a certain degree of uncertainty, and the uncertainty of fractures of different scales is also different. In general, the reliability of fractures established by seismic data is higher, the fractures identified by ant bodies have greater uncertainty, and the small-scale fractures generated by random simulation methods have greater uncertainty. In order to resolve the contradiction between the fracture model and the dynamic data, it is necessary to change the position of the fracture in space to re-establish the fracture geological model. Since the injection and production well spacing of carbonate fracture-cave reservoirs is often large, much larger than the scale of a single fracture, the fractures identified by the ant body can be screened based on the fracture credibility. The credibility of the fracture established by the ant body is a parameter that is positively correlated with the fracture area. Generally speaking, the smaller the area, the lower the credibility. By changing the positions of multiple selected fractures (i.e., translating fractures), they are staggered and spliced ​​together to achieve the purpose of connecting two wells. In the process of fracture translation, the size and occurrence of the fractures are not changed, so that the statistical law of the fractures remains unchanged.

[0104] Among them, the screening principles of cracks are:

[0105] Three aspects are mainly considered:

[0106] Well-to-well connectivity standard: It means that the selected fracture combinations can be translated to construct composite fracture channels to connect the injection and production well groups. Not every set of fracture combinations meets this standard. For example, when the strike of the selected fractures does not match the azimuth of the injection and production well group connection, it is impossible to construct an inter-well fracture channel by simply translating these fractures.

[0107] Fracture weight standard: It means that the selected fractures should be as close as possible to the injection and production well group, and have a high uncertainty on the other hand.

[0108] Connectivity data meets the standard: it means that when the constructed fracture channel is numerically simulated, it has seepage characteristics that are as consistent as possible with the connectivity data. When the type of dynamic data is tracer monitoring data, the simulated tracer curve is compared with the actual tracer curve to determine whether the constructed fracture channel meets the requirements. When the type of dynamic data is inter-well relative connectivity data, the corresponding inter-well fracture channel is constructed according to the degree of connectivity. One of the construction principles is that the seepage capacity of the fracture channel corresponding to the high-level connectivity is better than the seepage capacity of the fracture channel corresponding to the low-level connectivity.

[0109] In step S130, when the inter-well communication channel is constructed by fractures, constructing the initial inter-well communication channel according to the cave data and / or fracture data between the target well groups includes the following steps:

[0110] According to the fusion of different types of fractures, a discrete fracture three-dimensional spatial distribution model is formed as the initial well-to-well communication channel;

[0111] Adjusting the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups includes the following steps:

[0112] The orientation data in the fracture data in the discrete fracture three-dimensional spatial distribution model is adjusted to optimize the initial inter-well communication channel until the degree of fit corresponding to the optimized inter-well communication channel is greater than or equal to a preset threshold.

[0113] Specifically, the discrete fracture three-dimensional spatial distribution model is a multi-scale discrete network fracture (DFN) model, and its construction process is as follows:

[0114] like Figure 8 As shown in the figure, in view of the characteristics of diverse fracture genesis and large scale differences, a multi-scale discrete fracture model is established by using core, imaging, outcrop, geological, logging and seismic data in a hierarchical classification modeling method. First, the fracture scale is divided. According to the comprehensive recognition accuracy of multidisciplinary data, the fractures are divided into large-scale fractures (generally referring to fractures with particularly obvious geophysical response, which can be manually identified, and fault-level fractures), medium-scale fractures (generally referring to fractures that can be identified and extracted by means of geophysical attribute extraction) and small-scale fractures (fractures that can be observed in the core and have no obvious geophysical response); secondly, the genesis is divided, for example, the same scale fractures are divided into structural fractures and karst fractures according to the genesis; then the spatial distribution characteristics of fractures of different scales are characterized and described by combining core, imaging logging and field observation methods; finally, the large-scale and medium-scale fracture models are established by combining deterministic modeling and human-computer interaction, and the small-scale fractures of different karst genesis are established by stochastic modeling methods; finally, the established different types of fractures are merged to form a discrete fracture three-dimensional spatial distribution model.

[0115] The following takes the multi-scale fracture modeling of the S well area as an example to further illustrate the construction process of the multi-scale discrete network fracture model as follows:

[0116] a. Fault interpretation and characteristic analysis of S well area

[0117] The conventional methods in this field were used for fault interpretation, and the interpretation results show the characteristics of the faults in this area: small fault distance and short extension; densely developed faults in the north and less dense in the south; the north is mainly composed of small-scale faults, with a large number and an unclear dominant fault direction; the southern faults are relatively large in scale, but few in number, and mainly trend in the northeast direction; from the statistical direction, three major groups of faults are developed.

[0118] Analyze the crack direction and fault distribution characteristics. The more developed the fault is, the more groups and the larger the number of fractures are. Faults have a controlling effect on structural fractures. These characteristics are used to constrain subsequent structural fracture modeling.

[0119] The complex fracture network system in this area is often composed of tectonic fractures and karst fractures. The development characteristics, formation environment and distribution characteristics of karst fractures are mainly controlled by the dissolved body.

[0120] b. Crack parameter analysis

[0121] The well area is close to large faults, and the number of fractures encountered is large, accounting for 66% of the statistical number; some wells are far away from large faults, and the number of fractures encountered is small, accounting for 33% of the statistical number. The power function distribution law method is used to fit the observed data to obtain the fracture size distribution parameters; the ISIS iteration method is used to analyze the fracture set distribution parameters. The overall trend of the fractures in this area is NEE, with high-angle fractures (60-90) as the main ones, and medium and low-angle fractures are also developed. According to the fracture orientation and fracture density, the distribution of fractures in this well area has obvious vertical zoning and plane differences. It can be divided into 5 well sections in the longitudinal direction. According to the analysis results of fracture orientation and fracture density, the study area is divided into 5 layers for hierarchical modeling. Among the fractures developed near the fault, there is always a group of fractures whose direction is consistent with the fault direction, mainly high-angle fractures. The parts with large changes in structural curvature are the best places for fracture development, and low-angle fractures are developed.

[0122] c. Construction of discrete fracture network model

[0123] Following the principle of genetic control and stratification: In this well area, the fracture network model is established by combining the main controlling factors of fractures (structural faults, structural curvature, and seismic attributes) as constraint factors; the strata are divided into A, B, C, D, and E layers, and the fracture network model is established by combining the fracture genetic stratification. The discrete fracture network of a structural fracture in layer A is shown in the following figure. Fig. 9 As shown in the figure, the discrete fracture network of a certain dissolution fracture in layer A is realized as follows: Fig.10 The modeling process uses the Monte Carlo method with the help of the tool, and the fracture network model is realized multiple times with the standard well as the constraint, and the final model is optimized and fused.

[0124] d. Connectivity analysis

[0125] Reservoir connectivity analysis is performed based on the model to determine the consistency between the model and the actual well connectivity judgment.

[0126] In step S170, adjusting the attribute data in the cave data between the target well groups includes the following steps:

[0127] The radius and length of the pipe-type karst caves in the karst cave data between the target well groups are adjusted in a step-by-step manner. Since karst caves are generally large in scale and have high certainty, it is difficult to move them without affecting static geological data such as inherent seismic data. Therefore, the inter-well connection channel can only be optimized by adjusting its attribute data.

[0128] In step S170, adjusting the azimuth data in the fracture data between the target well groups includes the following steps:

[0129] Draw a vector in three-dimensional space with the marker injection well as the starting point and the marker production well as the end point to obtain the horizontal vector projected on the horizontal plane;

[0130] The strike vector of the crack is transformed so that the angle between the strike vector of the crack and the horizontal vector is an acute angle;

[0131] Compare the angle δ1 between the strike vector of the fracture and the projection vector, and the angle δ2 between the projection of the strike vector of the fracture on the horizontal plane and the horizontal vector between the wells;

[0132] According to the relationship between the angle δ1 and the angle δ2, the fracture data are divided into two categories;

[0133] At least part of the fracture data is selected from the two types of fracture data in turn for movement and splicing to optimize the inter-well communication channel, until the degree of fit corresponding to the optimized inter-well communication channel is greater than or equal to a preset threshold.

[0134] In step S150, the degree of agreement between the simulated amount of the produced tracer and the actual amount of the produced tracer is calculated by the following expression:

[0135]

[0136] Wherein, O is the agreement between the simulated amount of tracer produced and the actual amount of tracer produced, is the weighted peak value of the variation curve of the amount of the simulated tracer, X is the weighted peak value of the variation curve of the amount of the real tracer, and ΔT is the monitoring time of the liquid marker.

[0137] The weighted peak value is defined as the liquid marker output y for each collection. i With time x i The cumulative sum of the products is divided by the total output Y of the liquid marker.

[0138]

[0139] in, is the weighted peak value, y i is the output of liquid markers collected each time, x iis the interval between two consecutive collections of liquid markers, and n is the number of times the liquid markers are collected.

[0140]

[0141] Where Y is the total output of liquid marker, y j is the output of the liquid marker collected each time, and n is the number of times the liquid marker is collected.

[0142] In step S170, the optimal connection channel is optimized based on the Markov chain Monte Carlo simulation. Specifically, the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups are adjusted to obtain the optimized inter-well connection channel, and the optimized inter-well connection channel is used as the initial inter-well connection channel, and the process returns to step S140, including the following steps:

[0143] S171, adjusting the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups to obtain an optimized well-to-well communication channel;

[0144] S172, calculating the degree of agreement between the amount of simulated produced tracer corresponding to the optimized inter-well communication channel and the amount of actual produced tracer, and comparing it with the degree of agreement corresponding to the inter-well communication channel before optimization;

[0145] S173, when the degree of fit corresponding to the optimized inter-well communication channel is greater than the degree of fit corresponding to the inter-well communication channel before optimization, comparing the degree of fit corresponding to the optimized inter-well communication channel with a preset threshold;

[0146] S174, when the degree of fit corresponding to the optimized inter-well communication channel is greater than or equal to a preset threshold, the optimized inter-well communication channel is used as the determined inter-well communication channel;

[0147] S175, when the degree of fit corresponding to the optimized inter-well communication channel is less than a preset threshold, return to step 171 to optimize the inter-well communication channel again;

[0148] S176, when the degree of fit corresponding to the optimized inter-well communication channel is less than or equal to the degree of fit corresponding to the inter-well communication channel before optimization, return to step 171 to optimize the inter-well communication channel again.

[0149] The optimal connection channel selection based on Markov chain Monte Carlo simulation in step S170 is specifically exemplified as follows:

[0150] Under the premise of known prior knowledge, Bayesian methods are often used to obtain the posterior probability distribution of events. In this embodiment, it is necessary to obtain the posterior probability distribution of possible connected channels under the premise of the change curve of the actual produced liquid marker in the oil field. The Bayesian equation for obtaining the posterior probability can be constructed as follows:

[0151]

[0152] Among them, R refers to the connecting channel, T refers to the actual produced liquid marker change curve, P(R) is the prior probability distribution of a certain connecting channel, and L(T|R) refers to the possibility that the liquid marker change curve produced for a certain connecting channel is consistent with the actual production curve. Specifically, it can be approximately replaced by the above-mentioned degree of fit. When L(T|R) or P(R) is too complex to solve the above Bayesian equation, the Markov chain Monte Carlo method based on Metropolis sampling can be used to obtain the optimal solution of P(R|T) in the Bayesian equation, that is, the optimal connecting channel under the premise of the actual produced liquid marker change curve of the known oil field.

[0153] Table 2 is the pseudo code for the process of selecting the best connected channel using the Markov chain Monte Carlo method based on Metropolis sampling.

[0154] Table 2

[0155]

[0156] This embodiment uses the optimization method of Monte Carlo simulation to continuously reconstruct the connecting channels in the reservoir and move them so as to maximize the degree of fit.

[0157] Embodiment 2

[0158] In order to solve the above technical problems existing in the prior art, the embodiment of the present invention is based on the modeling method of the inter-well communication channel of the oil reservoir when the inter-well communication channel is constructed by fractures in the first embodiment.

[0159] Reference Fig.11 The modeling method of the inter-well communication channel of the oil reservoir of this embodiment includes the following steps:

[0160] S210, constructing dynamic communication channels between wells in the original reservoir;

[0161] S220, converting the azimuth of the fracture data;

[0162] S230, classifying the fracture data according to the converted azimuth angle;

[0163] S240, moving fractures to construct inter-well communication channels;

[0164] S250, numerical simulation of characteristic production data based on inter-well communication channels;

[0165] S260, calculating the degree of agreement between the characteristic data of actual oilfield production and the characteristic data of the numerical simulation, wherein the degree of agreement is used to indicate the degree of similarity between the real characteristic data and the simulated characteristic data;

[0166] S270, determining whether the degree of fit is greater than or equal to a preset threshold:

[0167] If yes, execute step S280;

[0168] If not, return to step S240, continuously move the fractures, and reconstruct the inter-well communication channel in the reservoir to make the matching degree as large as possible, wherein the reservoir communication channel corresponding to the maximum matching degree is used as the final output after optimization;

[0169] S280, output the constructed inter-well communication channel.

[0170] In step S210, since the fractures are small in scale and have a weak response to static geological data, in most cases, small-scale fractures are used as the basic unit for optimizing reservoir connectivity. A single fracture is small in scale, so several small-scale fractures are moved and effectively staggered to construct a larger-scale connectivity channel.

[0171] In step S220, a vector is drawn in three-dimensional space with the marker injection well as the starting point and the marker production well as the end point. The projection vector of the vector on the horizontal plane is taken to calculate the acute angle between the direction of each fracture and the projection vector, such as Fig.12a As shown, the vector from well A to well B represents the projection vector of the space vector represented by the marker injection well to the marker monitoring well on the plane, the dotted line represents the reverse extension line of the projection vector, and the dot-dash line is perpendicular to the projection vector. It can be seen that: the angle between the fracture whose azimuth is in the "+" area and the projection vector is acute, and the azimuth remains unchanged; the angle between the fracture whose azimuth is in the "-" area and the projection vector is obtuse, and 180° needs to be added to transform it to the "+" area. At this time, the angle between the azimuth of the fracture and the projection vector is acute.

[0172] In step S230, after calculating the acute angle between each crack and the projection vector, the cracks need to be classified. After the change of the azimuth angle in the previous step, the cracks and the projection vector are both at an acute angle. At this time, the cracks with an azimuth angle greater than the azimuth angle of the projection vector are classified into one category (recorded as 1), and the cracks with an azimuth angle less than the azimuth angle of the projection vector are classified into another category (recorded as 2). Figure 12bThe angle δ1 between the strike vector of the fracture and the projection vector is the fracture azimuth, and the angle δ2 between the projection of the strike vector of the fracture on the horizontal plane and the horizontal vector between the wells is the projection vector azimuth.

[0173] In step S240, since the distance between the marker injection well and the production well is far, a single fracture cannot connect the two wells, so consider moving the positions of multiple fractures so that the multiple fractures are "spliced" in space to connect the two wells. However, since the sizes, inclinations, and dips of the fractures are different, it is difficult to directly calculate the coordinates of the spliced ​​positions. In order to simplify the problem, the fracture can be simplified to a line segment with the center point of the fracture as the midpoint and a length equal to the length of the original fracture, and it is assumed that the fractures are at the same height. In this way, the problem becomes a math problem on a two-dimensional plane by splicing a series of line segments of different lengths and directions to connect two specified points in space. Then consider the splicing problem of fractures when the perforation depths of the two wells are inconsistent, and extend the solution to the three-dimensional case.

[0174] In order to make the connected cracks "fit" the trajectory of the projection vector as much as possible, the interlaced splicing of the cracks in the two previously classified cracks is selected in turn ( Fig.13 ), in order to make the cracks completely intersect each other, the intersection point of the two cracks is set to one quarter of the crack length.

[0175] like Fig.13 As shown, the length of each crack and the converted azimuth are substituted into the center point coordinate formula to derive the two-dimensional coordinates of the center point of each crack during the splicing process.

[0176]

[0177] Among them, point (x0, y0) is the two-dimensional coordinate of well A, point (x1, y1) is the two-dimensional coordinate of the center point of the first fracture in Figure 12 during the splicing process, and θ1 is Fig. 9 L1 is the azimuth of the first crack after transformation in FIG12 , and L2 is the length of the first crack in FIG12 .

[0178]

[0179] Among them, the point (x n ,y n ) is the two-dimensional coordinate of the center point of the nth crack in the splicing process in Figure 12, θ n is the azimuth angle of the nth crack after transformation in Figure 12, L n is the length of the nth crack in Figure 12.

[0180] Considering that the perforation depths of the injection well and the production well may be different, it is necessary to extend the two-dimensional coordinate formula to three dimensions, that is, to add the depth coordinate formula, such as Fig.14 As shown in the figure, the vector between well A and well B represents the vector from the liquid marker injection well to the production well. The azimuth of the vector is α, and the angle between the vector and the horizontal plane is θ. Assuming that the center point of a fracture (x1, y1, z1) is exactly on the vector, and the center point of the next fracture is recorded as (x2, y2, z2), if it is to be on the vector, then:

[0181]

[0182] Thus, the calculation formula of the depth coordinate of the center point is obtained.

[0183] In step S250, a fracture internal marker conduction model is established, and the characteristic production data can be liquid marker injection and production data. The conduction of liquid markers in fracture slices is simulated in the form of flow tubes, and the balance equation of displacement force and blocking force when the fracture conducts fluid is considered, and a fracture liquid marker conduction model based on fluid mechanics is established.

[0184] In step S250, the specific process of numerical simulation of characteristic production data based on the inter-well communication channel is as follows: Assume that wells A and B are connected by a regular fracture, and now a liquid marker is injected into well A and detected by well B. After the liquid marker is injected into well A, it is affected by convection and diffusion, and its distribution range continues to expand with the increase of the movement distance, and the concentration of the liquid marker continues to become dilute from the initial C0. The normal distribution is used to simulate the distribution of the concentration of the liquid marker segment in the main direction of movement after it flows out of well A:

[0185]

[0186] σ i 2 =2α i v i t

[0187] In the above formula, C0 is the initial concentration of the liquid marker, g / m 3 ; C i is the concentration of liquid marker transmitted to well B from the i-th fracture on day t, g / m 3 ; L i is the length of the channel connecting the two wells of the i-th fracture, m; ΔL i is the length of the liquid marker slug of the i-th fracture at well A, m; σ i is the standard deviation of the distribution curve; v i is the average flow velocity of the fluid in the i-th fracture, m / d; t is the time, d.

[0188]

[0189] Where V dis the total injection volume of liquid marker in well A, m 3 ;f j is the injection water distribution coefficient of well A to well B, which can be calculated from the ratio of the mass of liquid marker produced from well B to the mass of liquid marker injected into well A; i Represents the cross-sectional area of ​​the crack, m·μm.

[0190] According to the balance equation of fluid displacement force and blocking force, the flow rate of the i-th fracture is:

[0191]

[0192] In the formula, q i The unit is m 3 / d;a i is the width of the i-th crack, m; b i is the opening of the i-th crack, μm; μ is the fluid viscosity, MPa·s. And:

[0193] A i =a i b i

[0194] The average flow rate of the liquid marker can be obtained:

[0195]

[0196] In the formula, α i is the hydrodynamic dispersion of the liquid marker in the i-th fracture, m.

[0197] m o =C0V d f j

[0198] In the formula, m o Refers to the mass of tracer produced through each fracture, g / d; V d is the total injection volume of liquid marker in well A, m 3 Here, the mass of tracer extracted through all fractures is yi below.

[0199] In step S260, the degree of fit is defined as follows:

[0200] The degree of agreement is used to indicate the degree of deviation between the weighted peak value of the variation curve of the simulated liquid marker amount and the weighted peak value of the variation curve of the actual liquid marker amount within a certain time range, and the calculation formula is:

[0201]

[0202] in, is the weighted peak value of the variation curve of the simulated liquid marker amount, X is the weighted peak value of the variation curve of the actual liquid marker amount, and ΔT is the monitoring time of the liquid marker, in days.

[0203] The weighted peak value is defined as the output amount y of the liquid marker each time i With time x i The cumulative sum of the products is divided by the total output Y of the liquid marker.

[0204]

[0205]

[0206] Each time, fractures are randomly selected to form a connecting channel, and the connecting channel is used to simulate the conduction of liquid markers in it, and the corresponding degree of fit is calculated. When the degree of fit is less than a preset threshold, it means that the gap between the connecting channel and the actual underground situation is unacceptable, so the connecting channel is reconstructed and the liquid marker is simulated. The above process is repeated until the degree of fit is greater than the preset threshold. At this time, the reservoir connecting body of the constructed connecting channel is used as the final output result.

[0207] The following is application scenario 1 of the method for modeling inter-well communication channels in oil reservoirs of this embodiment.

[0208] Based on the dynamic connectivity of a unit reservoir and the actual liquid marker production data, the liquid marker injection well W1 and one of the liquid marker monitoring wells W2 were selected to test the above method. The actual liquid marker monitoring results showed that on the fourth day after the liquid marker was injected into the W1 well, the liquid marker concentration in the W2 well increased significantly, and reached the maximum value on the seventh day. Therefore, there must be a connecting channel between the two wells, which is consistent with the connectivity model before construction ( Fig.15a )contradiction.

[0209] The above method was applied to optimize the original reservoir connection. After 2138 iterations, a connection channel consisting of 22 fractures was formed between the marker injection well and the detection well ( Fig.15b ), it can be seen that the simulated liquid marker curve and the real liquid marker curve are very similar in morphology ( Fig.16 ), and the daily liquid marker data were also relatively close. After calculation, the degree of fit was 93.6%, which was greater than the pre-set threshold and met the fitting requirements.

[0210] The following is a second application scenario of the method for modeling inter-well communication channels in oil reservoirs of this embodiment.

[0211] Based on the original reservoir connectivity model and liquid marker data of a unit in the Tahe area, a liquid marker injection and production well group W in the unit was taken as the research object. The liquid marker injection and production well group consists of a liquid marker injection well W and 6 liquid marker production wells. The liquid marker monitoring results show that 4 of the production wells produce liquid markers, while 3 wells in the established connectivity model have no direct or indirect connection with caves or fractures, indicating that the established reservoir connectivity model is inconsistent with the dynamic data.

[0212] Using the above method, a connecting channel is established between the liquid marker injection well and the three production wells O1, O2, and O3 ( Fig.17 ), calculate the degree of fit corresponding to each well, which is greater than the preset threshold and meets the fitting requirements, as shown in Table 3. Table 3 is the remodeling result table of the W well group.

[0213] Table 3

[0214]

[0215] The modeling method of the reservoir inter-well connecting channel of the present embodiment qualitatively solves the contradiction between the actual characteristic production data and the reservoir connecting body represented by the computer by optimizing the reservoir connecting channel, and quantitatively solves the contradiction between the actual production data and the reservoir connecting body represented by the computer by repeatedly constructing the connecting channel until the calculated fit of the channel is greater than a preset threshold.

[0216] The remodeling process of the modeling method of the inter-well communication channel of the oil reservoir in this embodiment is automatically completed by a computer without human interference, with strong objectivity, fast modeling speed and high efficiency.

[0217] Embodiment 3

[0218] In order to solve the above-mentioned technical problems existing in the prior art, an embodiment of the present invention is based on the modeling method of the inter-well connecting channel of the oil reservoir when the inter-well connecting channel is constructed by a cave in Embodiment 1, wherein the modeling method of the inter-well connecting channel of the oil reservoir in this embodiment improves step S170.

[0219] In this embodiment, adjusting the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups specifically includes the following steps:

[0220] For two adjacent unconnected pipeline-type caves in the initial inter-well communication channel, determining a trend line for connecting the two adjacent unconnected pipeline-type caves according to the water flow direction in the pipeline-type cave;

[0221] Taking the vertical development probability of the pipeline-type cave as a constraint condition, the geometric statistical parameters of the trend line are adjusted to obtain an optimized inter-well communication channel, and the optimized inter-well communication channel is used as the initial inter-well communication channel, and the process returns to step S320.

[0222] The geometric statistical parameters include wavelength, amplitude height, width and thickness. Step S360, taking the vertical development probability of the pipeline-type cave as a constraint condition, adjusts the geometric statistical parameters of the trend line, including the following steps:

[0223] The trend line is divided into two parts: one end point a of the trend line and the karst cave segment disconnected from point a, and the other end point b of the trend line and the karst cave segment disconnected from point b;

[0224] Taking point a and point b as source points respectively, under the control of the trend line, setting the wavelength, amplitude height, width and thickness of the cave section disconnected from point a and the cave section disconnected from point b respectively, and taking the vertical development probability of the pipeline-type cave as a constraint condition, optimizing and simulating the cave section disconnected from point a and the cave section disconnected from point b;

[0225] The karst cave segment disconnected from point a and the karst cave segment disconnected from point b after the optimized simulation are overlapped, and the intersection is taken to obtain a pipeline-type cave used to connect the two adjacent unconnected pipeline-type caves, so that the two adjacent unconnected pipeline-type caves are in a connected state.

[0226] The implementation of step S360 is further explained below by taking the pipeline-type cave as an underground river cave as an example.

[0227] When dynamic data confirm that the wells are connected through underground river caves, while the underground river caves between the wells in the model are intermittent and not connected, it is proposed to use a target-based approach to optimize the model and connect the underground river caves.

[0228] The advantages of the target-based method are: the geometric statistical parameters, such as wavelength, amplitude, width, thickness and other data, can be determined artificially; the trend direction of river flow can be determined based on one's own understanding; the starting position of the river can be determined; and the simulation results can be guaranteed to be consistent with the conditional data in terms of vertical development probability.

[0229] Specific ideas such as Fig.18 As shown:

[0230] ① At the location where the river is disconnected, determine the two source points a and b, and determine the trend line according to the flow direction of the river.

[0231] ② Divide the river channel into two parts: one is point a and the river section disconnected from point a, the other is point b and the river section disconnected from point b.

[0232] ③ Take a and b as the source points respectively, and set the wavelength, amplitude height, width, and thickness (Table 4) under the control of the trend line to obtain the vertical development probability ( Fig.19 ) is used as a constraint condition, and a target-based random simulation is performed. The simulation results are statistically similar to the original results. Table 4 is a statistical table of modeling geometric parameters.

[0233] ④ Take the intersection of the two simulation results to obtain the overlapping river section.

[0234] ⑤Add the river section developed from a to b to the original discontinuous river channel.

[0235] ⑥ Finally, a continuous river channel with similar statistical laws is obtained.

[0236] Table 4

[0237] parameter Minimum value (m) Average value(m) Maximum value (m) wavelength 10 300 1500 Height 10 100 150 width 10 45 100 thickness 5 25 65

[0238] Embodiment 4

[0239] In order to solve the above-mentioned technical problems existing in the prior art, an embodiment of the present invention is based on an embodiment 1 of a method for modeling inter-well connecting channels in an oil reservoir when the inter-well connecting channels are constructed simultaneously by caves and fractures, wherein the method for modeling inter-well connecting channels in an oil reservoir of this embodiment improves step S170.

[0240] In this embodiment, adjusting the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups specifically includes the following steps:

[0241] For the fracture part in the inter-well communication channel, the azimuth data in the fracture data between the target well groups are adjusted according to the method in the second embodiment;

[0242] For the cave portion in the inter-well communication channel, the azimuth data in the cave data between the target well groups are adjusted according to the method in the third embodiment;

[0243] For the connection between the cave and the fracture in the inter-well communication channel, especially for the fractures around the cave, it is mainly during or after the formation of the cave that, with the increase of burial depth, the pressure of the overlying strata and surrounding rocks continues to increase, the cave collapses, the cave roof and the surrounding areas collapse, and fractures are formed. As the surface water dissolves along the fractures, they expand. At this time, the fractures are mainly located in the brecciated zone formed by the cave collapse. Through surface rate calculation and physical experiments, it can be obtained that the influence range of the brecciated zone formed by the cave channel collapse is 2.6-3.0 times the cave diameter. With this as the constraint condition, a constraint probability range is made to simulate the distribution of fractures on the edge of the cave.

[0244] Embodiment 5

[0245] In order to solve the above technical problems existing in the prior art, an embodiment of the present invention provides a modeling device for an inter-well communication channel in an oil reservoir.

[0246] The modeling device for the inter-well communication channel of the oil reservoir provided by the embodiment of the present invention comprises:

[0247] A construction module, used to construct an initial well-to-well communication channel based on cave data and / or fracture data between target well groups;

[0248] A calculation module, used for calculating the amount of simulated produced tracer according to the initial inter-well communication channel and inter-well tracer experimental data;

[0249] The judgment module is used to judge whether the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer is greater than or equal to a preset threshold: when the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer is greater than or equal to the preset threshold, the initial inter-well communication channel is used as the determined inter-well communication channel; when the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer is less than the preset threshold, the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups are adjusted to optimize the inter-well communication channel until the degree of agreement corresponding to the optimized inter-well communication channel is greater than or equal to the preset threshold.

[0250] Embodiment 6

[0251] In order to solve the above technical problems existing in the prior art, an embodiment of the present invention further provides a storage medium.

[0252] The storage medium of this embodiment stores a computer program, which implements the steps of the method in the above embodiment when executed by a processor.

[0253] Embodiment 7

[0254] In order to solve the above technical problems existing in the prior art, an embodiment of the present invention further provides a modeling device for inter-well communication channels in an oil reservoir.

[0255] The modeling device for the inter-well communication channel of the oil reservoir of this embodiment includes a memory and a processor. The memory stores a computer program, and the computer program implements the steps of the above method when executed by the processor.

[0256] 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 protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A method for determining a connecting channel between wells in an oil reservoir, characterized in that: The following steps are involved: S100, constructing an initial well-to-well communication channel according to cave data and / or fracture data between target well groups; S200, calculating the amount of simulated produced tracer according to the initial inter-well communication channel and inter-well tracer experimental data; S300, collecting the actual amount of produced tracer, and calculating the degree of agreement between the simulated amount of produced tracer and the actual amount of produced tracer; S400, optimizing the initial inter-well communication channel according to the degree of agreement between the simulated amount of produced tracer and the actual amount of produced tracer to obtain an optimized inter-well communication channel as the determined inter-well communication channel; The step S400 includes the following steps: S410, determining whether the consistency between the simulated amount of the produced tracer and the actual amount of the produced tracer is greater than or equal to a preset threshold: S420, when the degree of agreement between the simulated amount of produced tracer and the actual amount of produced tracer is greater than or equal to a preset threshold, the initial inter-well communication channel is used as the determined inter-well communication channel; S430, when the degree of agreement between the simulated amount of produced tracer and the actual amount of produced tracer is less than a preset threshold, adjust the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups to obtain an optimized well-to-well communication channel, and use the optimized well-to-well communication channel as the initial well-to-well communication channel, and return to step S200.

2. The method according to claim 1, characterized in that The step S400 includes the following steps: S410, determining whether the consistency between the simulated amount of the produced tracer and the actual amount of the produced tracer is greater than or equal to a preset threshold: S420, when the degree of agreement between the simulated amount of produced tracer and the actual amount of produced tracer is greater than or equal to a preset threshold, the initial inter-well communication channel is used as the determined inter-well communication channel; S430, when the degree of agreement between the simulated amount of the produced tracer and the actual amount of the produced tracer is less than a preset threshold, executing step S440; S440, adjusting the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups to obtain an optimized well-to-well communication channel; S450, calculating the degree of agreement between the amount of simulated produced tracer corresponding to the optimized inter-well communication channel and the amount of actual produced tracer, and comparing it with the degree of agreement corresponding to the inter-well communication channel before optimization; S460, when the degree of fit corresponding to the optimized inter-well communication channel is greater than the degree of fit corresponding to the inter-well communication channel before optimization, comparing the degree of fit corresponding to the optimized inter-well communication channel with a preset threshold; S470, when the degree of fit corresponding to the optimized inter-well communication channel is greater than or equal to a preset threshold, the optimized inter-well communication channel is used as the determined inter-well communication channel; S480, when the degree of fit corresponding to the optimized inter-well communication channel is less than a preset threshold, return to step 440 to optimize the inter-well communication channel again; S490, when the degree of fit corresponding to the optimized inter-well communication channel is less than or equal to the degree of fit corresponding to the inter-well communication channel before optimization, return to step 440 to optimize the inter-well communication channel again.

3. The method according to claim 1, characterized in that Before constructing the initial well-to-well communication channel according to the cave data and / or fracture data between the target well groups, the method further includes the following steps: According to the shape of the concentration curve of the real produced tracer between the target well groups, it is judged whether the inter-well communication channel is constructed by caves, fractures, or caves and fractures at the same time; The cave data and / or fracture data used to construct the inter-well communication channel are screened according to the judgment result.

4. The method according to claim 3, characterized in that Screening the cave data and / or fracture data for constructing the inter-well communication channel according to the judgment result includes the following steps: When the inter-well communication channel is constructed by a cave, pipeline-type cave data is selected as cave data for constructing the inter-well communication channel; When the inter-well communication channel is constructed by fractures, the fracture data used for constructing the inter-well communication channel are selected from the fractures identified by the ant body based on the fracture credibility; When the inter-well communication channel is constructed by caves and fractures, pipeline-type cave data is selected as cave data for constructing the inter-well communication channel, and fracture data for constructing the inter-well communication channel is selected from the fractures identified by the ant body based on the fracture credibility.

5. The method according to claim 3, characterized in that: When the inter-well communication channel is constructed by fractures, constructing the initial inter-well communication channel according to the cave data and / or fracture data between the target well groups includes the following steps: According to the fusion of different types of fractures, a discrete fracture three-dimensional spatial distribution model is formed as the initial well-to-well communication channel; Adjusting the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups includes the following steps: The orientation data in the fracture data in the discrete fracture three-dimensional spatial distribution model is adjusted to optimize the initial inter-well communication channel until the degree of fit corresponding to the optimized inter-well communication channel is greater than or equal to a preset threshold.

6. The method according to claim 3, characterized in that When the inter-well communication channel is constructed by a cave or a cave and a fracture, adjusting the attribute data in the cave data between the target well groups includes the following steps: For two adjacent unconnected pipeline-type caves in the initial inter-well communication channel, determining a trend line for connecting the two adjacent unconnected pipeline-type caves according to the water flow direction in the pipeline-type cave; Taking the vertical development probability of the pipeline-type cave as a constraint condition, the geometric statistical parameters of the trend line are adjusted.

7. The method according to claim 6, characterized in that The geometric statistical parameters include wavelength, amplitude height, width and thickness. Taking the vertical development probability of the pipeline-type cave as a constraint condition, adjusting the geometric statistical parameters of the trend line includes the following steps: The trend line is divided into two parts: one end point a of the trend line and the karst cave segment disconnected from point a, and the other end point b of the trend line and the karst cave segment disconnected from point b; Taking point a and point b as source points respectively, under the control of the trend line, setting the wavelength, amplitude height, width and thickness of the cave section disconnected from point a and the cave section disconnected from point b respectively, and taking the vertical development probability of the pipeline-type cave as a constraint condition, optimizing and simulating the cave section disconnected from point a and the cave section disconnected from point b; The karst cave segment disconnected from point a and the karst cave segment disconnected from point b after the optimized simulation are overlapped, and the intersection is taken to obtain a pipeline-type cave used to connect the two adjacent unconnected pipeline-type caves, so that the two adjacent unconnected pipeline-type caves are in a connected state.

8. A device for determining a communication channel between wells in an oil reservoir, characterized in that: include: A construction module, used to construct an initial well-to-well communication channel according to cave data and / or fracture data between target well groups; A calculation module, used for collecting the actual amount of produced tracer, and calculating the degree of agreement between the simulated amount of produced tracer and the actual amount of produced tracer; The optimization module is used to optimize the initial inter-well communication channel according to the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer to obtain the optimized inter-well communication channel as the determined inter-well communication channel, specifically including: judging whether the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer is greater than or equal to a preset threshold: when the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer is greater than or equal to the preset threshold, taking the initial inter-well communication channel as the determined inter-well communication channel; when the degree of agreement between the amount of simulated produced tracer and the amount of real produced tracer is less than the preset threshold, adjusting the attribute data in the cave data and / or the orientation data in the fracture data between the target well groups to obtain the optimized inter-well communication channel, taking the optimized inter-well communication channel as the initial inter-well communication channel, and returning to the calculation module.

9. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A device for determining a communication channel between wells in an oil reservoir, comprising a memory and a processor, characterized in that: The memory stores a computer program, which implements the steps of the method according to any one of claims 1 to 7 when executed by the processor.

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