Unsteady state oil and gas reservoir evaluation method, device, equipment and medium

Abstract

The invention belongs to the technical field of oil and gas field exploration and development, and particularly relates to an evaluation method, device and equipment for an unsteady state oil and gas reservoir and a medium. The method comprises the steps of obtaining geological background data and seismic data of a region where a target stratum is located; the formation water density and the oil-gas density of the target layer are obtained; according to the seismic data and the geological background data, a current structural map of the target stratum in the current period and a historical structural map of the target stratum in the previous period are determined, and oil and gas traps with different characteristics exist in geological structures in different periods; determining a distance and a height difference according to the current structural map and the historical structural map; and according to the formation water density, the oil-gas density, the distance and the height difference, evaluating the unsteady state oil-gas reservoir of the target stratum. The method is high in operability and reliable in evaluation result, and has good applicability to oil gas enrichment area optimization and development well location deployment of the oil field.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas field exploration and development, and specifically relates to an evaluation method, device, equipment and medium for a non-steady-state oil and gas reservoir. Background Art

[0002] The non-steady state of oil and gas reservoirs mainly refers to the fact that the original stable oil and gas reservoirs are affected by external conditions such as later tectonic movements, which causes changes in the oil-gas-water interface and pressure system, and the whole is in a dynamic adjustment state. The most important feature of the non-steady state of oil and gas reservoirs is the tilt of the oil-gas-water interface or the inversion of the spatial relationship.

[0003] In existing research, CN109918769B discloses a method for calculating the amount of unsteady-state water intrusion in fracture-cavity reservoirs using an instantaneous equation, and CN111079341B discloses a method for coupling intelligent completion and reservoir unsteadiness based on an iterative algorithm. The reservoir unsteadiness involved in the two methods refers to the dynamic changes in the fluid state between the wellbore and the reservoir during the production process of the development well, and is not an evaluation of unsteady-state oil and gas reservoirs.

[0004] At present, there are few evaluation methods for the non-steady state of oil and gas reservoirs. In Volume 13, Issue 3, Marine Oil and Gas Geology, 2008, Sun Longde et al. defined the concept of non-steady-state oil and gas reservoirs, and studied the evolutionary stages and development characteristics of non-steady-state oil and gas reservoirs; in Volume 36, Issue 1, Petroleum Exploration and Development, 2009, Sun Longde et al. analyzed the causes of the inclined oil-water interface in the non-steady-state reservoir of the Hudson Oilfield in Tarim, and improved the concept of non-steady-state reservoirs based on physical simulation; in Volume 27, Issue 6, Lithological Reservoirs, 2015, Chen Jie et al. analyzed the non-steady-state characteristics and causes of the oil reservoir in the A Oilfield in Iran, and guided the selection of favorable development areas; in Volume 41, Issue 2, Petroleum Experimental Geology, 2019, Fu Zhifang et al. studied the stratigraphic characteristics and tectonic evolution history of Block 17 in the Oriente Basin, and pointed out the impact of differential tectonic evolution on non-steady-state reservoirs.

[0005] However, the existing technology for the research on the non-steady state of oil and gas reservoirs mainly focuses on the concept and definition of non-steady state oil and gas reservoirs, the structural evolution history of oil and gas reservoirs, the characteristics of oil-gas-water interface, etc. There are few analyses on the causes of the change from steady state to non-steady state of oil and gas reservoirs, and the main controlling factors and related parameters that affect the non-steady state of oil and gas reservoirs cannot be quantitatively characterized, and no evaluation method for the non-steady state of oil and gas reservoirs has been formed. Summary of the invention

[0006] In view of the above technical problems, the present invention proposes a method, device, equipment and medium for evaluating non-steady-state oil and gas reservoirs. The present application obtains geological background data and seismic data of the area where the target layer is located; obtains the formation water density and oil and gas density of the target layer; determines the current structural map of the target layer in the current period and the historical structural map of the previous period according to the seismic data and the geological background data, wherein the geological structures of different periods have oil and gas traps with different characteristics; determines the distance and elevation difference according to the current structural map and the historical structural map, wherein the distance and elevation difference are obtained by comparing the high point of the oil and gas trap in the current structural map with the high point of the oil and gas trap in the historical structural map; evaluates the non-steady-state oil and gas reservoir of the target layer according to the formation water density, the oil and gas density, the distance and the elevation difference. The present invention has strong operability and reliable evaluation results, and has good applicability for selecting oil and gas enrichment areas in oil fields and deploying development wells.

[0007] To solve the above technical problems, the technical solution adopted by the present invention includes four aspects.

[0008] In a first aspect, a method for evaluating a non-steady-state oil and gas reservoir is provided, comprising: obtaining geological background data and seismic data of an area where a target layer is located; obtaining formation water density and oil and gas density of the target layer; determining a current structural map of the target layer in a current period and a historical structural map of a previous period based on the seismic data and the geological background data, wherein oil and gas traps of different characteristics exist in geological structures of different periods; determining a distance and a height difference based on the current structural map and the historical structural map, wherein the distance and the height difference are obtained by comparing the high points of the oil and gas traps in the current structural map with the high points of the oil and gas traps in the historical structural map; and evaluating the non-steady-state oil and gas reservoir of the target layer based on the formation water density, the oil and gas density, the distance and the height difference.

[0009] In some embodiments, determining the current structural map of the target layer in the current period and the historical structural map of the previous period based on the seismic data and the geological background data includes: determining the boundary of the target layer based on the seismic data; filling the boundary according to the geological background data to obtain the current structural map of the target layer in the current period and the historical structural map of the previous period.

[0010] In some embodiments, the evaluating of the non-steady-state oil and gas reservoir of the target layer based on the formation water density, the oil and gas density, the distance and the height difference includes: determining the re-migration driving force of the non-steady-state oil and gas reservoir based on the formation water density, the oil and gas density, the height difference and the distance; and evaluating the non-steady-state oil and gas reservoir based on the re-migration driving force.

[0011] In some embodiments, the re-migration driving force is determined by the following formula: F = (ρw-ρo)gVsin(arctanΔh / L)*103; wherein ρw is the formation water density, in g / cm3, ρo is the oil and gas density, in g / cm3, g is the gravitational acceleration, in m / s2, V is the unit volume, Δh is the height difference, L is the distance, and F is the driving force for the re-migration of oil and gas, in N.

[0012] In some embodiments, the evaluating the non-steady-state oil and gas reservoir according to the re-migration driving force includes: obtaining core observation data, logging descriptions and logging curves in the area where the target layer is located; determining the dominant direction of re-migration of the non-steady-state oil and gas reservoir according to the current structural map, the historical structural map, the logging descriptions, the core observation data and the logging curves; and evaluating the non-steady-state oil and gas reservoir according to the dominant direction of re-migration and the re-migration driving force.

[0013] In some embodiments, determining the dominant direction of re-migration of the non-steady-state oil and gas reservoir based on the current structural map, the historical structural map, the logging description, the core observation data and the logging curve includes: determining the provenance azimuth based on the core observation data, the logging description and the logging curve; determining the relative azimuth based on the current structural map and the historical structural map, wherein the relative azimuth is the relative azimuth of the high point of the oil and gas trap in the current structural map relative to the high point of the oil and gas trap in the historical structural map; determining the dominant direction of re-migration of the non-steady-state oil and gas reservoir based on the provenance azimuth and the relative azimuth.

[0014] In some embodiments, determining the provenance azimuth according to the core observation data, the logging description and the logging curve includes: determining the sedimentary layer of the target layer according to the logging description, the core observation data and the logging curve; determining the provenance azimuth of the sedimentary layer according to the logging curve.

[0015] In the second aspect, the present application proposes an evaluation device for non-steady-state oil and gas reservoirs, comprising: a first acquisition module, used to obtain geological background data and seismic data of the area where the target layer is located; a second acquisition module, used to obtain the formation water density and oil and gas density of the target layer; a first determination module, used to determine the current structural map of the target layer in the current period and the historical structural map of the previous period based on the seismic data and the geological background data, wherein the geological structures of different periods have oil and gas traps with different characteristics; the second determination module, used to determine the distance and the elevation difference based on the current structural map and the historical structural map, wherein the distance and the elevation difference are obtained by comparing the high points of the oil and gas traps in the current structural map with the high points of the oil and gas traps in the historical structural map; the first evaluation module, used to evaluate the non-steady-state oil and gas reservoir of the target layer based on the formation water density, the oil and gas density, the distance and the elevation difference.

[0016] In a third aspect, the present application proposes an electronic device, comprising: a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the method described in the first aspect is performed.

[0017] In a fourth aspect, the present application proposes a storage medium, which stores a computer program that can be executed by one or more processors, and the computer program can be used to implement the method described in the first aspect.

[0018] Beneficial effects created by the present invention: This application obtains geological background data and seismic data of the area where the target layer is located; obtains the formation water density and oil and gas density of the target layer; determines the current structural map of the target layer in the current period and the historical structural map of the previous period according to the seismic data and the geological background data, wherein the geological structures of different periods have oil and gas traps with different characteristics; determines the distance and elevation difference according to the current structural map and the historical structural map, wherein the distance and elevation difference are obtained by comparing the high point of the oil and gas trap in the current structural map with the high point of the oil and gas trap in the historical structural map; evaluates the non-steady-state oil and gas reservoir of the target layer according to the formation water density, the oil and gas density, the distance and the elevation difference. The present invention has strong operability and reliable evaluation results, and has good applicability for selecting oil and gas-rich areas in oil fields and deploying development wells. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The scope of the present disclosure may be better understood by reading the following detailed description of exemplary embodiments in conjunction with the accompanying drawings. The drawings included are:

[0020] Figure 1 An overall flow chart of a method for evaluating a non-steady-state oil and gas reservoir provided in an embodiment of the present application;

[0021] Figure 2 An address structure diagram of a certain area in a certain basin provided in an embodiment of the present application;

[0022] Figure 3 A structural diagram of a certain region in a certain historical period provided in an embodiment of the present application;

[0023] Figure 4 A current structural diagram of a certain area provided in an embodiment of the present application;

[0024] Figure 5 A structural block diagram of a non-steady-state oil and gas reservoir evaluation device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings. The described embodiments should not be regarded as limiting the present application. All other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of this application.

[0026] In the following description, reference is made to “some embodiments”, which describe a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0027] If similar descriptions of "first\second\third" appear in the application documents, the following instructions will be added. In the following description, the terms "first\second\third" involved are merely used to distinguish similar objects and do not represent a specific ordering of the objects. It can be understood that "first\second\third" can be interchanged in a specific order or sequence where permitted, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0029] Embodiment 1:

[0030] However, the existing technology for the research on the non-steady state of oil and gas reservoirs mainly focuses on the concept and definition of non-steady state oil and gas reservoirs, the structural evolution history of oil and gas reservoirs, the characteristics of oil-gas-water interface, etc. There are few analyses on the causes of the change from steady state to non-steady state of oil and gas reservoirs, and the main controlling factors and related parameters that affect the non-steady state of oil and gas reservoirs cannot be quantitatively characterized, and no evaluation method for the non-steady state of oil and gas reservoirs has been formed.

[0031] In view of the problems existing in the prior art, such as Figure 1 As shown, the present application provides a method for evaluating a non-steady-state oil and gas reservoir, and the method is applied to an electronic device, and the electronic device can be a server, a mobile terminal, a computer, a cloud platform, etc. The function implemented by the device data processing provided in the embodiment of the present application can be implemented by calling a program code by a processor of the electronic device, wherein the program code can be stored in a computer storage medium, and the method for evaluating a non-steady-state oil and gas reservoir includes:

[0032] Step S1: Obtain geological background data and seismic data of the area where the target layer is located.

[0033] Unsteady oil and gas reservoirs are stored in a certain stratum, so in this application, the stratum where the unsteady oil and gas reservoir is located is called the target stratum, and the development of the target stratum is the same as that of the region where it is located. Since the existing technical means cannot directly measure the direct information of the space where the oil and gas reservoir is located, in order to evaluate the unsteady oil and gas reservoir in this application, it is necessary to combine the geological background data and seismic data of the region where the target stratum is located.

[0034] Step S2: Obtaining the formation water density and oil and gas density of the target layer.

[0035] According to the oil and gas migration theory, the buoyancy generated by the difference between the density of oil or natural gas and the density of formation water along the migration direction is the main driving force for the re-migration of oil and gas. The definition of a non-steady-state oil and gas reservoir is an oil and gas reservoir in a dynamic adjustment state. Therefore, we can evaluate the non-steady-state oil and gas reservoir of the target layer by quantitative characterization through the formation water density and oil and gas density. Therefore, this application needs to obtain the formation water density and oil and gas density of the target layer, among which the oil and gas density and formation water density can be directly measured.

[0036] Step S3: Determine the current structural map of the target layer in the current period and the historical structural map of the previous period based on the seismic data and the geological background data, wherein the geological structures in different periods have oil and gas traps with different characteristics.

[0037] In some embodiments, step S3 "determining the current structural map of the target layer in the current period and the historical structural map of the previous period according to the seismic data and the geological background data" includes:

[0038] Step S31: Determine the boundary of the target layer according to the seismic data.

[0039] Seismic data can reflect the structural characteristics of the area, so we can calibrate and interpret the main stratigraphic boundaries, that is, the boundaries of the target layer, on the seismic time section based on the seismic data and the time-depth relationship. Then, we use the human-machine collaborative workstation seismic interpretation technology to perform a fine structural interpretation of the reflection layer at the top and bottom of the target layer, so that the target layer boundary is more in line with the actual situation. At this time, we get a target layer boundary on a time section. Many of our geological studies are based on the depth scale, so we also need to use the time-depth relationship to convert the target layer boundary of the time layer to the target layer boundary of the depth layer, that is, we get the boundary of the target layer mentioned in this application.

[0040] Step S32: Filling the boundary according to the geological background data to obtain the current structural map of the target layer in the current period and the historical structural map in the previous period.

[0041] Based on the boundary obtained in step S31, the boundary is filled according to the geological background data. Because the geological background data includes the address data of each period, the thickness of various strata in the target layer can be calculated and mapped according to the geological background data, and then the thickness of the target layer is superimposed from bottom to top according to the sedimentation filling method, so as to obtain the structural map of each period. Among them, the main research in this application is the non-steady-state oil and gas reservoir of the current period, and the main factors affecting the non-steady-state oil and gas reservoir of the current period are the geological structure of the current period and the geological structure of the period adjacent to the current period. Therefore, in this application, the geological structure of the current period is taken as the current geological structure map, and the geological structure of the previous period is removed to become the historical structure map.

[0042] Step S4: determining a distance and a height difference according to the current structural map and the historical structural map, wherein the distance and the height difference are obtained by comparing a high point of an oil and gas trap in the current structural map with a high point of an oil and gas trap in the historical structural map.

[0043] In the stratum where the oil and gas reservoir exists, an oil and gas trap will be formed. The oil and gas trap is a space for storing oil and gas reservoirs. When the geological structure changes, it may affect the structure or characteristics of the oil and gas trap, thereby causing the oil and gas reservoirs in the oil and gas trap to adjust and form a non-stable oil and gas reservoir. Therefore, we can obtain the changes in the oil and gas trap by comparing the characteristics of the oil and gas traps in the structural map of the two periods, and this change will affect the migration mode of the non-stable oil and gas reservoir to a certain extent. In order to make the comparison result representative, the high points of the oil and gas traps are mainly compared in this application, and then the distance and height difference, i.e., the height difference, of the high points of the oil and gas traps in the current structural map relative to the high points of the oil and gas traps in the historical structural map are obtained.

[0044] Step S5: Evaluate the non-steady-state oil and gas reservoir of the target layer according to the formation water density, the oil and gas density, the distance and the height difference.

[0045] After obtaining the formation water density, oil and gas density, distance and height difference, a quantitative parameter can be obtained, based on which the unsteady oil and gas reservoir can be evaluated.

[0046] In some embodiments, step S5 "evaluating the unsteady oil and gas reservoir of the target layer according to the formation water density, the oil and gas density, the distance and the height difference" includes:

[0047] Step S51: determining the re-migration driving force of the non-steady-state oil and gas reservoir according to the formation water density, the oil and gas density, the height difference and the distance.

[0048] Step S52: Evaluate the unstable oil and gas reservoir according to the re-migration driving force.

[0049] The present application obtains a quantitative parameter, i.e., re-migration force, which can be used to evaluate the unstable oil and gas reservoir by the following formula based on the formation water density, oil and gas density, distance and height difference, and then evaluates the unstable oil and gas reservoir based on the re-migration force. The smaller the migration force, the higher the unstable degree of the unstable oil and gas reservoir and the longer the time in the unstable state.

[0050] In some embodiments, the formula for obtaining the quantitative parameters that can be used to evaluate the unsteady oil and gas reservoir according to the formation water density, oil and gas density, distance and height difference is as follows:

[0051] F=(ρ w -ρ o )gVsin(arctanΔ h / L)*10 3 .

[0052] In the formula, ρ w is the formation water density, in g / cm 3 , ρ o is the density of oil and gas, in g / cm 3 , g is the acceleration due to gravity, in m / s 2 , V is the unit volume, Δ h is the height difference, L is the distance, and F is the driving force for oil and gas migration again, with the unit of N.

[0053] The above evaluation of the non-steady-state oil and gas reservoir by the secondary migration force is only based on the magnitude of the force. In order to make the evaluation more comprehensive, the direction of the secondary migration force also needs to be considered.

[0054] Therefore, in some embodiments, step S52 of "evaluating the unstable oil and gas reservoir according to the re-migration force" includes:

[0055] Step S521: Obtain core observation data, logging description and logging curves in the area where the target layer is located.

[0056] Step S522: determining the dominant direction of re-migration of the non-steady-state oil and gas reservoir according to the current structural map, the historical structural map, the logging description, the core observation data and the logging curve.

[0057] When the geological structure changes, the oil and gas traps will change. When the oil and gas traps change, the oil and gas reservoirs will move and adjust. However, the factors that affect the movement direction of the oil and gas reservoirs are not only the changes in the oil and gas traps, but also the influence of the sedimentary layers.

[0058] Therefore, in some embodiments, step S522 "determine the dominant direction of re-migration of the non-steady-state oil and gas reservoir according to the current structural map, the historical structural map, the logging description, the core observation data and the logging curve" includes:

[0059] Step S5221: Determine the provenance azimuth according to the core observation data, the logging description and the logging curve.

[0060] It is mentioned above that the factors affecting the adjustment direction of oil and gas reservoir migration are not only the changes in oil and gas closures, but also the influence of sedimentary layers. The provenance azimuth in step S5221 refers to the source direction of the sedimentary layer.

[0061] Therefore, in some embodiments, step S5221 "determining the provenance azimuth according to the core observation data, the logging description and the logging curve" includes:

[0062] Step S52211: Determine the sedimentary layer of the target layer according to the logging description, the core observation data and the logging curve.

[0063] Step S52212: Determine the provenance azimuth of the sedimentary layer according to the logging curve.

[0064] Sedimentary layer data can be obtained during drilling, core observation data, logging, and well logging curves, so the location of the sedimentary layer in the target layer can be determined based on these data. After the location of the sedimentary layer is determined, the movement direction of the sedimentary layer can be obtained based on the data in the well logging data, such as lithology curves, electrical curves, etc., and then the source direction of the sedimentary layer, that is, the source azimuth, can be obtained.

[0065] Step S5222: determining a relative azimuth according to the current structural map and the historical structural map, wherein the relative azimuth is the relative azimuth of the high point of the oil and gas trap in the current structural map relative to the high point of the oil and gas trap in the historical structural map.

[0066] The re-migration of oil and gas reservoirs is affected by the movement of sedimentary layers and the movement caused by the change of oil and gas traps. Therefore, in this application, it is also necessary to determine the direction of oil and gas reservoir migration caused by the change of oil and gas traps based on the current structural map and the historical structural map, that is, the relative azimuth.

[0067] Step S5223: Determine the dominant direction of re-migration of the non-steady-state oil and gas reservoir according to the provenance azimuth and the relative azimuth.

[0068] Under the influence of sedimentary layers alone, oil and gas reservoirs should migrate along the sedimentary facies from fine to coarse. When they migrate only under the influence of changes in oil and gas traps, they will migrate from the location of the historical oil and gas traps to the location of the current oil and gas traps. The migration direction is the relative azimuth. Therefore, the relative azimuth and the provenance azimuth can be regarded as two forces that affect the migration of oil and gas reservoirs. The directionality of these two forces will greatly affect the degree and duration of non-steady-state oil and gas reservoirs. Therefore, according to the basic law of force, we can get that when the angle between the provenance azimuth and the relative azimuth is smaller, the degree of non-steady-state oil and gas reservoirs is lower and the duration is longer. When the angle between the provenance azimuth and the relative azimuth is larger, the degree of non-steady-state oil and gas reservoirs is higher and the duration is longer.

[0069] Step S523: Evaluate the non-steady-state oil and gas reservoir according to the dominant direction of re-migration and the driving force of re-migration.

[0070] After obtaining the dominant direction of re-migration, the dominant direction of re-migration and the driving force of re-migration can be combined to evaluate the non-steady-state oil and gas reservoirs, and both the dominant direction of re-migration and the driving force of re-migration are quantitative parameters, which solves the problem in the prior art that there is little analysis on the causes of the change from steady state to non-steady state of oil and gas reservoirs, and the main controlling factors and related parameters that affect the non-steady state of oil and gas reservoirs cannot be quantitatively characterized.

[0071] This application relies on seismic data to accurately identify and divide sedimentary strata, calibrate the boundaries of the target layers, and use time-depth conversion to complete the detailed interpretation of the current structure. Based on the filling-in method, the structural sedimentary evolution process is restored, and the paleo-structural characteristics of different periods are reproduced. Through the analysis of sedimentary environment and sedimentary phases, combined with the theory of oil and gas migration, the non-steady-state characteristics of oil and gas reservoirs are quantitatively evaluated based on the structural evolution characteristics of oil and gas reservoirs, reservoir heterogeneity, and oil, gas and water fluid properties.

[0072] Embodiment 2:

[0073] Take a block in a certain basin as an example. The sedimentary cover of this block is extremely thick from the Jurassic to the Neogene. The Triassic-Jurassic is back-arc rift sedimentation, with Chapiza Formation, Santiag Formation and other strata developed; the Early Cretaceous to the end of the Late Cretaceous is post-rift depression sedimentation, with Hollin Formation and Napo Formation sedimentation; the end of the Cretaceous to the Neogene is Andean foreland sedimentation, with Tena Formation, Tiyuyacu Formation, Orteguaza Formation, Chalcana Formation, Arajuno Formation, Chambira Formation and Mesa Formation and other strata developed. Among them, the marine black shale developed in the Napo Formation is the main source rock, the four sets of sandstones of Hollin, T, U and M are the main reservoirs, the sedimentary facies is offshore-river delta type, the source supply direction is southeast, and the extremely thick mudstone formation of the Tena Formation is widely developed, which is the regional sedimentary cover ( Figure 2 ).

[0074] Based on the interpretation of seismic data and the analysis of the wells that have been drilled, the existing wells B and C are located in the same nose-shaped structure. Well B is located in the high part of the structure and only encountered the U oil-bearing sandstone of the Napo Group. The oil test result is about 20 barrels of oil per day. Well C is located in the low part of the structure and encountered three sets of oil-bearing sandstones of the Napo Group T, U and M. The oil test result of the U oil-bearing sandstone is about 150 barrels of oil per day. Comprehensive analysis shows that the embodiment has a significantly inclined oil-water interface. The distribution range of the two oil-bearing traps B and C is inconsistent with the distribution range of the actual structural traps. It is a typical non-steady-state oil and gas reservoir ( Figure 3 ).

[0075] Through the paleo-structural restoration and sedimentary evolution analysis of the target layer, it is found that during the early Andean foreland tectonic evolution period, there were two long-axis anticline traps with a northeast-southwest trend. The C trap is located at the high part of the structure with many oil-bearing layers, while the B trap is located at the low part of the structure with few oil-bearing layers, stable reservoirs, and horizontal oil-water contacts ( Figure 4 ). During the late Andean foreland tectonic evolution period, affected by tectonic movement, the original anticline structural oil and gas reservoir was transformed into the current short nose structural oil and gas reservoir, and the reservoir state also changed from stable to unstable, and oil and gas migrated from C trap to B trap, thus forming the current unstable oil and gas reservoir.

[0076] Research on regional sedimentary facies and sedimentary environment shows that the sediment source direction of the reservoir sand body is southeast, that is, the reservoir heterogeneity is weak along the southeast direction, which is convenient for oil and gas migration. The current main direction of oil and gas migration is from the high part of the C closure to the high part of the B closure, that is, the northeast direction. The two are almost vertical. Therefore, the oil and gas now migrate along the southeast direction where the reservoir heterogeneity is strong, which hinders the migration of oil and gas, delays the dynamic adjustment process of the oil and gas reservoir, and facilitates the formation of non-steady-state oil and gas reservoirs.

[0077] The final conclusion is: the main target layer has a formation dip of about 1°, the terrain is too flat, the density of the drilled crude oil is about 0.94g / cm3, the density of the formation water is about 1g / cm3, and the difference in oil and water density is small. The formula calculates that the power of unit volume of oil and gas along the migration direction is 495N, and the power value is small, that is, the ability of oil and water to adjust quickly is weak, and it is easy to form and maintain the non-steady-state characteristics of the oil and gas reservoir for a long time.

[0078] Embodiment 3:

[0079] Based on the foregoing embodiments, the embodiments of the present application provide an evaluation device for a non-steady-state oil and gas reservoir. The modules included in the device and the units included in each module can be implemented by a processor in a computer device; of course, they can also be implemented by a specific logic circuit; in the implementation process, the processor can be a central processing unit (CPU, Central Processing Unit), a microprocessor (MPU, Microprocessor Unit), a digital signal processor (DSP, Digital Signal Processing) or a field programmable gate array (FPGA, Field Programmable Gate Array), etc.

[0080] like Figure 5 As shown, a non-steady-state oil and gas reservoir evaluation device includes: a first acquisition module 1, a second acquisition module 2, a first determination module 3, a second determination module 4 and a first evaluation module 5.

[0081] The first acquisition module 1 is used to obtain geological background data and seismic data of the area where the target layer is located. The second acquisition module 2 is used to obtain the formation water density and oil and gas density of the target layer. The first determination module 3 is used to determine the current structural map of the target layer in the current period and the historical structural map of the previous period based on the seismic data and the geological background data, wherein the geological structures of different periods have oil and gas traps with different characteristics. The second determination module 4 is used to determine the distance and height difference based on the current structural map and the historical structural map, wherein the distance and the height difference are obtained by comparing the high point of the oil and gas trap in the current structural map with the high point of the oil and gas trap in the historical structural map. The first evaluation module 5 is used to evaluate the non-steady-state oil and gas reservoir of the target layer based on the formation water density, the oil and gas density, the distance and the height difference.

[0082] In some embodiments, the first determination module 3 includes: a third determination module and a first execution module.

[0083] The third determination module is used to determine the boundary of the target layer according to the seismic data. The first execution module is used to fill the boundary according to the geological background data to obtain the current structural map of the target layer in the current period and the historical structural map in the previous period.

[0084] In some embodiments, the first evaluation module 5 includes: a fourth determination module and a second evaluation module.

[0085] The fourth determination module is used to determine the re-migration driving force of the unstable oil and gas reservoir according to the formation water density, the oil and gas density, the height difference and the distance. The second evaluation module is used to evaluate the unstable oil and gas reservoir according to the re-migration driving force.

[0086] In some embodiments, the second evaluation module includes: a third acquisition module, a fifth determination module and a third evaluation module.

[0087] The third acquisition module is used to obtain core observation data, logging description and logging curves in the area where the target layer is located. The fifth determination module is used to determine the dominant direction of re-migration of the non-steady-state oil and gas reservoir based on the current structural map, the historical structural map, the logging description, the core observation data and the logging curve. The third evaluation module is used to evaluate the non-steady-state oil and gas reservoir based on the dominant direction of re-migration and the driving force of re-migration.

[0088] In some embodiments, the fifth determination module includes: a sixth determination module, a seventh determination module and an eighth determination module.

[0089] The sixth determination module is used to determine the provenance azimuth according to the core observation data, the logging description and the logging curve. The seventh determination module is used to determine the relative azimuth according to the current structural map and the historical structural map, wherein the relative azimuth is the relative azimuth of the high point of the oil and gas trap in the current structural map relative to the high point of the oil and gas trap in the historical structural map. The eighth determination module is used to determine the dominant direction of re-migration of the non-steady-state oil and gas reservoir according to the provenance azimuth and the relative azimuth.

[0090] In some embodiments, the sixth determination module includes: a ninth determination module and a tenth determination module.

[0091] The ninth determination module is used to determine the sedimentary layer of the target layer according to the logging description, the core observation data and the logging curve. The tenth determination module is used to determine the provenance azimuth of the sedimentary layer according to the logging curve.

[0092] Each module in the above-mentioned evaluation device for a non-steady-state oil and gas reservoir can be implemented in whole or in part by software, hardware, and a combination thereof. Each of the above-mentioned modules can be embedded in or independent of the processor in the device in the form of hardware, or can be stored in the memory in the processing device in the form of software, so that the processor can call and execute the operations corresponding to each of the above modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0093] Embodiment 4:

[0094] The third aspect provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of a method for evaluating a non-steady-state oil and gas reservoir are implemented.

[0095] Embodiment 5:

[0096] The fourth aspect provides a storage medium, which stores a computer program that can be executed by one or more processors, and the computer program can be used to implement the steps of any one of the methods for evaluating non-steady-state oil and gas reservoirs in the first aspect.

[0097] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0098] It should be understood that "one embodiment" or "an embodiment" mentioned throughout the specification means that specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in various embodiments of the present application, the size of the sequence number of the above-mentioned processes does not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application. The above-mentioned sequence numbers of the embodiments of the present application are only for description and do not represent the advantages and disadvantages of the embodiments.

[0099] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0100] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0101] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units; they may be located in one place or distributed on multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0102] In addition, all functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may be a separate unit, or two or more units may be integrated into one unit; the above-mentioned integrated units may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0103] A person of ordinary skill in the art can understand that: all or part of the steps of implementing the above-mentioned method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above-mentioned method embodiment; and the aforementioned storage medium includes: mobile storage devices, read-only memories (ROM, Read Only Memory), disks or optical disks, etc. Various media that can store program codes.

[0104] Alternatively, if the above-mentioned integrated unit of the present application is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application can essentially or in other words, the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium and includes a number of instructions for a controller to execute all or part of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0105] The above is only an implementation method of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for evaluating a non-steady-state oil and gas reservoir, characterized in that: include: Obtain geological background information and seismic data of the target layer area; Obtaining formation water density and oil and gas density of the target layer; Determine the current structural map of the target layer in the current period and the historical structural map of the previous period according to the seismic data and the geological background data, wherein the geological structures in different periods have oil and gas traps with different characteristics; Determining a distance and a height difference according to the current structural map and the historical structural map, wherein the distance and the height difference are obtained by comparing a high point of an oil and gas trap in the current structural map with a high point of an oil and gas trap in the historical structural map; The non-steady-state oil and gas reservoir of the target layer is evaluated according to the formation water density, the oil and gas density, the distance and the height difference.

2. The evaluation method for a non-steady-state oil and gas reservoir according to claim 1, characterized in that: Determining the current structural map of the target layer in the current period and the historical structural map of the previous period according to the seismic data and the geological background data includes: Determining the boundary of the target layer according to the seismic data; The boundary is filled according to the geological background data to obtain the current structural map of the target layer in the current period and the historical structural map in the previous period.

3. The evaluation method for a non-steady-state oil and gas reservoir according to claim 1, characterized in that: The evaluating of the unsteady oil and gas reservoir of the target layer according to the formation water density, the oil and gas density, the distance and the height difference comprises: Determine the re-migration driving force of the unsteady oil and gas reservoir according to the formation water density, the oil and gas density, the height difference and the distance; The unsteady-state reservoir is evaluated based on the re-migration dynamics.

4. The evaluation method for a non-steady-state oil and gas reservoir according to claim 3, characterized in that: The re-movement kinetic energy is determined by the following formula: F=(ρ w -r o )gVsin(arctanΔ h / L*10 3 ; In the formula, ρ w is the formation water density, in g / cm 3 , ρ o is the density of oil and gas, in g / cm 3 , g is the acceleration due to gravity, in m / s 2 , V is the unit volume, Δ h is the height difference, L is the distance, and F is the driving force for oil and gas migration again, with the unit of N.

5. The evaluation method for a non-steady-state oil and gas reservoir according to claim 3, characterized in that: The method of evaluating the unstable oil and gas reservoir according to the re-migration driving force includes: Obtain core observation data, logging description and logging curves in the target layer area; Determine the dominant direction of re-migration of the non-steady-state oil and gas reservoir according to the current structural map, the historical structural map, the logging description, the core observation data and the logging curve; The non-steady-state oil and gas reservoir is evaluated according to the dominant direction of re-migration and the driving force of re-migration.

6. The evaluation method for a non-steady-state oil and gas reservoir according to claim 5, characterized in that: The determining of the dominant direction of re-migration of the non-steady-state oil and gas reservoir according to the current structural map, the historical structural map, the logging description, the core observation data and the logging curve comprises: Determine the provenance azimuth according to the core observation data, the logging description and the logging curve; Determine a relative azimuth according to the current structural map and the historical structural map, wherein the relative azimuth is the relative azimuth of the high point of the oil and gas trap in the current structural map relative to the high point of the oil and gas trap in the historical structural map; The dominant direction of re-migration of the non-steady-state oil and gas reservoir is determined according to the provenance azimuth and the relative azimuth.

7. The method for evaluating a non-steady-state oil and gas reservoir according to claim 6, characterized in that: The determining of the provenance azimuth according to the core observation data, the logging description and the logging curve comprises: Determine the sedimentary layer of the target layer according to the logging description, the core observation data and the logging curve; The provenance azimuth of the sedimentary layer is determined according to the well logging curve.

8. An evaluation device for a non-steady-state oil and gas reservoir, characterized in that: include: The first acquisition module is used to obtain geological background data and seismic data of the area where the target layer is located; A second acquisition module is used to acquire the formation water density and oil and gas density of the target layer; A first determination module is used to determine the current structural map of the target layer in the current period and the historical structural map of the previous period according to the seismic data and the geological background data, wherein the geological structures in different periods have oil and gas traps with different characteristics; A second determination module is used to determine a distance and a height difference according to the current structural map and the historical structural map, wherein the distance and the height difference are obtained by comparing a high point of the oil and gas trap in the current structural map with a high point of the oil and gas trap in the historical structural map; The first evaluation module is used to evaluate the non-steady-state oil and gas reservoir of the target layer according to the formation water density, the oil and gas density, the distance and the height difference.

9. An electronic device, characterized in that: include: A memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the method according to any one of claims 1 to 7 is executed.

10. A storage medium, characterized in that: The computer program stored in the storage medium can be executed by one or more processors, and the computer program can be used to implement the method according to any one of claims 1 to 7.

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