Method, device and equipment for exploring remaining oil of oil reservoir and storage medium

Abstract

The invention discloses an exploration method, device and equipment for remaining oil of an oil reservoir and a storage medium, and the method comprises the steps that a measuring point and a base point of the oil reservoir are determined; injecting colloid containing magnetoelectric particles into the oil reservoir; acquiring magnetic induction intensity of the measuring point and the base point before and after colloid injection through a superconducting magnetometer; analyzing the magnetic induction intensity of the measuring point and the base point before and after colloid injection through a data analysis device, and determining a magnetic change equivalent field diagram of the oil reservoir before and after colloid injection; according to the magnetic change equivalent field map and the reservoir dynamic understanding, a remaining oil saturation plane distribution map of the reservoir is determined, and the remaining oil saturation plane distribution map comprises remaining oil boundary distribution characteristics and water flow dominant channel distribution characteristics of the reservoir. Through the technical scheme provided by the invention, oil and gas distribution characteristics such as remaining oil distribution and a water flow dominant channel development area of an oil reservoir can be directly and accurately drawn, and a reliable basis is provided for comprehensive adjustment in the later period of oil field development.

Description

Technical Field

[0001] This application belongs to the field of oilfield development technology, and in particular relates to a method, apparatus, equipment and storage medium for exploring residual oil in an oil reservoir. Background Technology

[0002] Exploring the distribution of residual oil in an oil reservoir is a crucial step in the extraction of remaining crude oil. Generally, after natural energy development, water injection development, and even tertiary oil recovery, residual crude oil still constitutes a significant proportion of the total reservoir reserves. In many cases, the amount of residual oil is even equivalent to the cumulative produced oil. However, after long-term water injection development, the distribution of residual oil in the vertical direction and across the entire reservoir plane is highly complex due to factors such as the heterogeneity of the reservoir, the shielding effect of various levels of fault systems, structural variations, sedimentary microfacies, and the distance between injection and production wells. Even though reservoir engineers have summarized some methods for residual oil research, reservoir types vary greatly, and the distribution pattern of residual oil boundaries in one reservoir may not be applicable to other reservoirs.

[0003] Furthermore, the distribution of residual oil in a planar pattern is highly uncertain, influenced not only by formation pressure from oil and water well production but also by reservoir heterogeneity, changing with structural elevation and porosity / permeability, making it difficult to ascertain the distribution pattern of residual oil. Additionally, when the oil layer thickness is small and falls outside the resolution of 3D seismic data, it becomes even more impossible to accurately define the boundaries of residual oil. Therefore, no single system can directly, quickly, and quantitatively detect and describe the distribution boundaries and specific locations of residual oil. Summary of the Invention

[0004] The embodiments of this application provide a method, apparatus, equipment and storage medium for exploring remaining oil in an oil reservoir. It can directly, quickly and accurately delineate the distribution of remaining oil in the reservoir, the development zone of water flow dominance channels and other oil and gas planar distribution characteristics, thereby providing a reliable basis for comprehensive adjustment in the later stage of oilfield development.

[0005] Other features and advantages of this application will become apparent from the following detailed description, or may be learned in part from practice of this application.

[0006] According to a first aspect of the embodiments of this application, a method for detecting residual oil in an oil reservoir is provided, comprising:

[0007] Determine the measuring points and benchmarks of the reservoir;

[0008] Injecting a colloid containing magnetoelectric microparticles into the reservoir;

[0009] The magnetic induction intensity of the measuring point and the base point before and after the colloid injection is obtained by the superconducting magnetometer.

[0010] The data analysis device is used to analyze the magnetic induction intensity of the measuring point and the base point before and after the colloid injection, and to determine the magnetic change isofield map of the reservoir before and after the colloid injection.

[0011] Based on the magnetic variation isofield map and the reservoir dynamics, the remaining oil saturation plane distribution map of the reservoir is determined. The remaining oil saturation plane distribution map includes the remaining oil boundary distribution characteristics and the water flow dominant channel distribution characteristics of the reservoir.

[0012] In some embodiments of this application, based on the foregoing scheme, an injection device is further provided on the surface of the reservoir. The injection device includes a booster pump, a pressure gauge, and a water injection system. The injection of a colloid containing magnetoelectric microparticles into the reservoir includes:

[0013] The injection device injects a colloid containing magnetoelectric particles into the formation of the injection well.

[0014] In some embodiments of this application, based on the foregoing scheme, the step of analyzing the magnetic induction intensity of the measuring point and the base point before and after the colloid injection using the data analysis device to determine the magnetic change isofield map of the reservoir before and after the colloid injection includes:

[0015] The magnetic induction intensity of the measuring point and the base point before and after the colloid injection is analyzed by the data analysis device to obtain the changes in magnetic induction intensity of the measuring point and the base point before and after the colloid injection.

[0016] Based on the change in magnetic induction intensity, the magnetic field map of the reservoir before and after the colloid injection is determined.

[0017] Therefore, to clarify the remaining oil boundary in water-driven reservoirs, a magnetoelectric microparticle colloid can be injected into the formation using an injection device. Data analysis equipment can then be used to obtain magnetic induction intensity isofield maps based on changes in magnetic anomalies at the baseline points before and after injection. This provides direct evidence for the distribution of remaining oil.

[0018] In some embodiments of this application, based on the foregoing scheme, determining the planar distribution map of the remaining oil saturation of the reservoir according to the magnetic change isofield map and the reservoir dynamics understanding includes:

[0019] Based on the magnetic change isofield diagram, determine the total magnetic change isofield diagram, the vertical magnetic change isofield diagram, and the planar magnetic change isofield diagram;

[0020] Based on the total magnetic variation isofield map, vertical magnetic variation isofield map, planar magnetic variation isofield map, and the reservoir dynamics, the planar distribution map of the remaining oil saturation of the reservoir is determined.

[0021] Thus, by drawing contour maps of total magnetic anomaly, vertical magnetic anomaly, and planar magnetic anomaly, and combining these with reservoir dynamics, a comprehensive planar distribution map of remaining oil saturation can be drawn. This allows for a direct, rapid, and accurate depiction of oil and gas distribution characteristics, such as remaining oil and gas boundaries, water flow dominance channels, and macroscopic pore and fracture development zones, providing a reliable basis for comprehensive adjustments in the later stages of oilfield development.

[0022] In some embodiments of this application, based on the foregoing scheme, obtaining the magnetic induction intensity of the measuring point and the base point before and after the colloid injection using the superconducting magnetometer includes:

[0023] The background magnetic induction intensity of the measuring point and the base point is obtained in advance using the superconducting magnetometer.

[0024] When the background magnetic induction intensity meets the error requirements, the magnetic induction intensity of the measuring point and the base point before and after the colloid injection is obtained by the superconducting magnetometer.

[0025] In some embodiments of this application, based on the foregoing scheme, determining the planar distribution map of the remaining oil saturation of the reservoir according to the magnetic change isofield map and the reservoir dynamics understanding includes:

[0026] Based on the stable magnetic field region and abnormal magnetic field region in the magnetic change isofield diagram, the high-value abnormal region and the micro-magnetic abnormal region are determined.

[0027] Based on the high-value anomaly region, the micromagnetic anomaly region, and the understanding of reservoir dynamics, a planar distribution map of the remaining oil saturation of the reservoir is determined.

[0028] According to a second aspect of the embodiments of this application, an apparatus for detecting residual oil in an oil reservoir is provided, wherein a superconducting magnetometer and a data analysis device are installed on the surface of the oil reservoir, comprising:

[0029] The survey network determination module is used to determine the survey points and benchmark points of the reservoir;

[0030] A colloid injection module is used to inject a colloid containing magnetoelectric microparticles into the reservoir.

[0031] The magnetic anomaly measurement module is used to obtain the magnetic induction intensity of the measuring point and the base point before and after the colloid injection using the superconducting magnetometer.

[0032] The magnetic anomaly analysis module is used to analyze the magnetic induction intensity of the measuring point and the base point before and after the colloid injection through the data analysis device, and to determine the magnetic change isofield map of the reservoir before and after the colloid injection.

[0033] The remaining oil analysis module is used to determine the remaining oil saturation plane distribution map of the reservoir based on the magnetic change isofield map and the reservoir dynamics. The remaining oil saturation plane distribution map includes the remaining oil boundary distribution characteristics and the water flow dominant channel distribution characteristics of the reservoir.

[0034] In some embodiments of this application, based on the foregoing scheme, an injection device is also provided on the surface of the reservoir. The injection device includes a booster pump, a pressure gauge, and a water injection system. The colloid injection module is used to inject a colloid containing magnetic and electric microparticles into the formation of the water injection well through the injection device.

[0035] According to a third aspect of the embodiments of this application, an exploration device for residual oil in an oil reservoir is provided, including a processor and a memory, wherein the memory stores computer program instructions that can be executed by the processor, and when the processor executes the computer program instructions, it implements the steps of the method described in any of the first aspects above.

[0036] According to a fourth aspect of the embodiments of this application, a computer-readable storage medium is provided, wherein computer program instructions are stored therein, and when executed by a processor, the computer program instructions cause the processor to perform the steps of the method as described in any of the first aspects above.

[0037] In this application, a colloid containing magnetoelectric microparticles is injected into the reservoir. A superconducting magnetometer is used to acquire the magnetic induction intensity at measuring points and baselines in the reservoir before and after colloid injection. A data analysis device is then used to analyze the magnetic induction intensity at these points to determine the magnetic field map of the reservoir before and after colloid injection. Based on the magnetic field map and reservoir dynamics, a planar distribution map of the remaining oil saturation is determined. This planar distribution map includes the distribution characteristics of the remaining oil boundary and the distribution characteristics of the water flow dominant channels. The technical solution provided in this application enables the use of magnetoelectric measuring equipment to measure the magnetic changes in the formation before and after the injection of magnetoelectric microparticle colloids within the reservoir, obtaining a magnetic field map. Combined with reservoir dynamics, a planar distribution map of the remaining oil saturation can be drawn. This directly, quickly, and accurately depicts the oil and gas distribution characteristics such as the remaining oil and gas boundary, water flow dominant channels, and macroscopic pore and fracture development zones, thus guiding the tapping of remaining oil potential in the oilfield.

[0038] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0039] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0040] Figure 1 A flowchart illustrating a method for detecting residual oil in a reservoir is shown in one embodiment;

[0041] Figure 2 A schematic diagram of the planar layout of the survey network and base points in a certain work area is shown in one embodiment;

[0042] Figure 3 A schematic diagram of the planar distribution of residual oil saturation is shown in one embodiment;

[0043] Figure 4 A schematic diagram of the longitudinal distribution of residual oil saturation is shown in one embodiment;

[0044] Figure 5 A block diagram of a reservoir residual oil detection device is shown in one embodiment;

[0045] Figure 6 A schematic diagram of a reservoir residual oil detection system is shown in one embodiment;

[0046] Figure 7 A schematic diagram of a reservoir residual oil detection device is shown in one embodiment. Detailed Implementation

[0047] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0048] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0049] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0050] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0051] Currently, the detection of remaining oil in the vertical direction mainly relies on well logging technology for measurement and interpretation, such as azimuth resistivity imaging, whole-bore microresistivity imaging, multi-frequency multi-probe electromagnetic wave logging, CO ratio logging, etc., forming a series of well logging interpretation methods, theories, and approaches for water-flooded formations. However, for the study of the planar distribution of remaining oil, which is more important for tapping the potential of remaining oil, there is currently no direct and quantitative detection method other than qualitative-semi-quantitative four-dimensional seismic analysis. We can only rely on production test data and apply indirect methods such as reservoir engineering theory, dynamic analysis, and reservoir numerical simulation for prediction and inference, and verify them through expensive drilling and coring, which has significant limitations.

[0052] Furthermore, the distribution of residual oil in the plane is more uncertain. It is affected not only by the formation pressure brought about by the production of oil and water wells, but also by the heterogeneity of the reservoir. It changes with the structural height and porosity and permeability, making it difficult to figure out the distribution pattern of residual oil. In addition, when the oil layer thickness is small and outside the resolution of 3D seismic data, it is even more impossible to accurately define the boundary of residual oil.

[0053] Therefore, the field of reservoir development urgently needs advanced, practical, and simple technologies and equipment to directly and quickly determine the distribution boundaries and specific locations of remaining oil.

[0054] To address the aforementioned issues, this application provides a method, apparatus, and equipment for detecting remaining oil in a reservoir. By using magnetic surveying in water-driven reservoirs and comparing the magnetic changes before and after the injection of magnetoelectric microparticles into the formation within the reservoir working area using magnetoelectric measuring equipment, a magnetic change isofield map is obtained. Then, combined with reservoir dynamics, a planar distribution map of remaining oil saturation is drawn. This can directly and accurately delineate the distribution of remaining oil in the reservoir, the development zone of water flow dominance channels, and other oil and gas distribution characteristics, providing a reliable basis for comprehensive adjustments in the later stages of oilfield development and achieving the goal of guiding the tapping of remaining oil potential in the oilfield.

[0055] The following section uses the S oil field in Kazakhstan as an example to illustrate this application in detail with reference to the accompanying drawings.

[0056] The S oilfield in Kazakhstan has a geomagnetic dip angle of 53°, an angle of 7° westward between the positive x-axis and the north direction of the geomagnetic field, an effective magnetization dip angle of 90°, and a work area of ​​120 km². 2 The oil layer is buried at a depth of approximately 850m. In one embodiment of this application, a superconducting magnetometer and data analysis device can be installed on the surface of the oil field.

[0057] Please see Figure 1 , Figure 1 A flowchart illustrating a method for detecting residual oil in a reservoir, as shown in one embodiment, is illustrated. Figure 1 As shown, the method may include steps 101 to 105.

[0058] In step 101, the measuring points and benchmark points of the reservoir are determined.

[0059] It is understandable that the aforementioned reservoirs may refer to reservoir work areas that require residual oil analysis.

[0060] Since the selection of the magnetic survey network must consider the target under study, the distribution range of the surrounding rock, geological and geophysical characteristics, and the required depth of exploration, in some embodiments, the survey network can be arranged according to the work area range and topography of the reservoir. For example, Figure 2 As shown, the line spacing between two adjacent measuring lines of the measuring point and measuring network is between 50m and 1 / 2 well spacing, and the point spacing is 25m.

[0061] Understandably, to improve observation accuracy, control the influence of instrument zero-point displacement and other factors on the instrument during observation, and convert observation results to a uniform level, it is necessary to establish benchmark points in magnetic surveying. Therefore, after setting up the survey network, benchmark points and a benchmark point network can be determined. Benchmark points are divided into total benchmark points and sub-benchmark points. The main function of the total benchmark point and sub-benchmark points is to serve as the starting points for observing the magnetic field. The total benchmark point is the starting point for detecting the magnetic induction intensity across the entire area, while the sub-benchmark points are the starting points for the magnetic induction intensity in specific survey areas. The benchmark points and the total benchmark point are connected to form the benchmark point network.

[0062] In some embodiments, after determining the survey network and baseline points, a background value survey can be conducted. At this time, a background magnetic anomaly acquisition device can be set up. This device consists of a superconducting magnetometer installed on the reservoir surface and a data analysis device. It is used to pre-measure the background value, i.e., the background magnetic induction intensity, and meets the error theory requirements: the mean square error (m) of the observed anomaly should be lower than or equal to the lowest meaningful anomaly extreme value (ΔT). min The total mean square error of the magnetic measurement should be 1 / 6 to 1 / 5 of the mean square error. Since the main steps of the magnetic measurement are performed independently, the total mean square error of the magnetic measurement should satisfy:

[0063]

[0064] Where m1 is the standard deviation of instrument consistency; m2 is the standard deviation of the selection of base points and the network measurement of base points; m3 is the standard deviation of field observations, i.e., diurnal variation observations; m4 is the standard deviation of various corrections; m5 is the standard deviation of the calculation; and m6 is the standard deviation of other causes.

[0065] Diurnal variation observation refers to establishing a diurnal variation observation station using a superconducting magnetometer in a location with a stable magnetic field, free from external magnetic field interference, and in a stable environment. Observations begin daily before sunrise and before the superconducting magnetometer used for measuring points within the work area begins operation, and end after the superconducting magnetometer used for measuring points within the work area finishes operation. The time recording or settings of the superconducting magnetometer for diurnal variation observation and the superconducting magnetometer for measuring points must be synchronized, and the measured data is analyzed and processed using a data analysis device.

[0066] In step 102, a colloid containing magnetoelectric microparticles is injected into the reservoir.

[0067] In some embodiments, an injection device is also provided on the surface of the reservoir, which includes a booster pump, a pressure gauge, and a water injection system. In this case, the equipment equipped with a method for detecting remaining oil in the reservoir can move relative to the surface, facilitating the injection of a colloid containing magnetoelectric particles into the target formation of the water injection well via the injection device.

[0068] It is understandable that, in order to inject magnetoelectric microparticle colloids into deeper formations, the magnetoelectric microparticle colloidal solution is delivered to the target formation through a booster pump at a certain pressure. Under higher pressure, the magnetoelectric microparticle colloids can be injected into deeper locations within the reservoir, thereby enabling a more accurate determination of the distribution range of remaining oil in the reservoir. After being injected into the formation, this colloidal solution will continue to displace crude oil and accumulate in low oil saturation areas such as water-dominant channels and areas of strong water flooding formed by long-term water injection.

[0069] Based on long-term observation and research using various data sources, it is believed that the water-driven channel is approximately the size of a cylinder with an inner diameter equal to the diameter of the pore. The magnetic anomaly, i.e., the change in magnetic induction intensity before and after colloid injection, can be approximated by an infinitely long horizontal cylinder model.

[0070]

[0071]

[0072]

[0073] Where μ0: permeability in vacuum, Henry / meter; h: depth of the cylinder's center, meters; m s : Effective linear magnetization, and m s =M s S;M s Effective magnetization, nT; S: Cross-sectional area of ​​the cylinder, m²2 i s : Effective magnetization tilt angle, i.e., the angle with the horizontal plane, is 90°; I0: Geomagnetic field tilt angle; A': The angle between the positive x-axis direction and the north direction of the geomagnetic field; H ax Z a ΔT and ΔT are the magnetization intensity in the x-direction, the vertical magnetization intensity, and the total magnetic field anomaly, respectively.

[0074] In step 103, the magnetic induction intensity of the measuring point and the base point before and after the colloid injection is obtained by the superconducting magnetometer.

[0075] Understandably, in order to compare the changes in magnetic induction intensity (i.e., magnetic anomalies) before and after the injection of magnetoelectric microparticle colloids into the formation within the reservoir area, a magnetic anomaly re-measurement unit can be established. This magnetic anomaly re-measurement unit can be composed of a superconducting magnetometer and data analysis equipment located on the reservoir surface.

[0076] Specifically, before injecting the magnetoelectric microparticle colloid, a ground-based superconducting magnetometer can be used to obtain the magnetic induction intensity corresponding to the location information of a certain fixed measuring point. After injecting the magnetoelectric microparticle colloid, the ground-based superconducting magnetometer further obtains the magnetic induction intensity corresponding to the location information of that fixed measuring point.

[0077] In step 104, the magnetic induction intensity of the measuring point and the base point before and after the colloid injection is analyzed by the data analysis device to determine the magnetic change isofield map of the reservoir before and after the colloid injection.

[0078] It is understandable that when a large difference in magnetic induction intensity is detected at a certain measuring point location before and after colloid injection, it indicates that the magnetic induction intensity in that area differs due to the colloid injection, suggesting the presence of gel aggregation at that measuring point location. This allows for a preliminary determination that the area represents the boundary of remaining oil in the reservoir. Therefore, in this embodiment, a data analysis device is used to analyze the magnetic induction intensity of each measuring point and base point before and after colloid injection, yielding the changes in magnetic induction intensity at each measuring point and base point. Based on these changes in magnetic induction intensity, an isofield map of the magnetic changes in the reservoir before and after colloid injection can be determined.

[0079] Among them, the magnetic change isofield map can be understood as a map obtained by connecting measuring points with the same magnetic induction intensity change value on the survey area plan map.

[0080] Understandably, the magnetic induction intensity measured before and after the injection of the colloid forms a set of data, which can include hundreds or even thousands of values, thus ensuring a more accurate determination of the area where the magnetic anomaly is distributed. Similarly, by measuring the magnetic induction intensity at all measuring points within the reservoir working area, and based on the changes in magnetic anomalies caused by the injection of magnetoelectric microparticle colloids into the formation, an isopleth map of the reservoir's magnetic changes can be obtained.

[0081] In step 105, based on the magnetic change isofield map and the reservoir dynamics, the remaining oil saturation plane distribution map of the reservoir is determined. The remaining oil saturation plane distribution map includes the remaining oil boundary distribution characteristics and the water flow dominant channel distribution characteristics of the reservoir.

[0082] In this embodiment, by analyzing the measurement data of the superconducting magnetometer, specifically the changes in magnetic induction intensity at each measuring point and baseline before and after the colloid injection, it is possible to distinguish between stable magnetic field regions and abnormal magnetic field regions, and extract high-value abnormal regions and micro-magnetic abnormal regions. Then, based on the detailed geology and development dynamics of the reservoir, including sand body width, sand body thickness, sand body connectivity, well logging interpretation of water-flooded layers, and production status of oil and water wells, a planar distribution map of remaining oil saturation is drawn.

[0083] Among them, the high-value anomaly area can refer to the area with a high change value of magnetic induction intensity in the magnetic change isofield map. It can reflect the aggregation of gel, so it can be preliminarily judged that the area is the boundary of the remaining oil in the reservoir or the water flow dominant channel area of ​​the remaining oil in the reservoir.

[0084] Micromagnetic anomaly regions refer to areas in the magnetic field map where the change in magnetic induction intensity is relatively small. These regions can reflect the gradual change in magnetic induction intensity, thus allowing for a preliminary assessment of the connectivity of the sand bodies in these areas.

[0085] It is understandable that, since there are multiple sub-layers in the vertical direction of the reservoir, magnetoelectric particles are injected in a general manner, thus preferentially injecting into the dominant layers with higher permeability. Therefore, the dominant channel layers can be determined by the magnetic variation isofield map of each sub-layer in the vertical direction. Similarly, in the plane, magnetoelectric particles will also advance along the direction of higher permeability to determine the distribution boundary of the dominant water flow channel in the plane. Therefore, in some embodiments, the total magnetic variation isofield map, the vertical magnetic variation isofield map, and the planar magnetic variation isofield map can be determined based on the magnetic variation isofield map; then, based on the total magnetic variation isofield map, the vertical magnetic variation isofield map, the planar magnetic variation isofield map, and the reservoir dynamics, the planar distribution map of the remaining oil saturation of the reservoir can be determined.

[0086] The total magnetic variation isofield map can be drawn using ΔT obtained from the aforementioned formula, and the vertical magnetic variation isofield map can be drawn using H obtained from the aforementioned formula.ax The plotted data, along with the isopleth map of the planar magnetic variation, can be used to calculate Z using the aforementioned formula. a The drawing was obtained.

[0087] In some applications, when performing residual oil analysis on fractured reservoirs, the residual oil exploration method of this application yields a residual oil saturation plane distribution map that not only reflects the distribution characteristics of residual oil boundaries and water flow dominance channels, but also the distribution characteristics of macroscopic pore and fracture development zones. In other words, the residual oil exploration method of this application is applicable to different types of reservoirs.

[0088] For example, such as Figure 3 As shown, based on the drilling data, it was originally believed that the channel between the two wells was a continuous sand body with clear boundaries, and the flow direction of the river could be clearly seen. However, from the magnetic variation isofield map, there is a clear interruption in the micromagnetic residual anomaly area between the wells, indicating that there is a deterioration band of sand body. Therefore, it is believed that the channel sand body between the two wells is discontinuous, with some inter-channel sand bodies in between. When compiling the map, the residual oil saturation plane distribution map needs to be broken.

[0089] For example, such as Figure 4 As shown in the data, the formation contains a stable sand body with no interlayers, and the original oil-water interface is clear. However, the vertical magnetic anomaly indicates a discontinuity in the sand body and the presence of interlayer bands. Analysis of the planar and vertical micromagnetic residual anomaly regions allows for a direct and accurate depiction of the remaining oil boundaries, water flow dominance channels, and other planar distribution characteristics of oil and gas, thus guiding the selection of reservoir development methods.

[0090] This application provides a method for exploring remaining oil in a reservoir. By comparing the magnetic changes in the reservoir area before and after the injection of magnetoelectric microparticles into the formation using magnetic surveying in water-drive reservoirs with measurements taken by magnetoelectric measuring equipment, a magnetic change isofield map is obtained. Then, combined with reservoir dynamics, a planar distribution map of remaining oil saturation is drawn. This method can directly and accurately delineate the distribution of remaining oil and the development of water flow dominance channels, as well as other oil and gas distribution characteristics. This provides a reliable basis for comprehensive adjustments in the later stages of oilfield development, and aims to guide the tapping of remaining oil potential in the oilfield.

[0091] Understandably, magnetic surveys of residual oil distribution, within the accuracy range of existing magnetic survey instruments, can detect residual oil distribution in ultra-deep (vertical depth 7000m) medium-to-high permeability sandstone formations, as well as in medium-deep (around 2000m) water-injected reservoirs undergoing development. The determination of residual oil distribution using magnetic anomalies is a dynamic understanding based on the characteristics of magnetic anomalies, combined with rock and mineral properties and geological conditions. Furthermore, the magnetic analysis method for residual oil distribution requires magnetic surveys and geological interpretation of the results. The quality of the interpretation determines the development effectiveness and economic benefits of using magnetic surveys to find residual oil, depends on the interpreters' understanding of magnetic field theory, geological theory, and development dynamics, and, most importantly, on the quality of the magnetic survey data.

[0092] The following describes an embodiment of the apparatus described in this application, which can be used to execute the method for detecting residual oil in a reservoir as described in the above embodiments of this application. For details not disclosed in the apparatus embodiments of this application, please refer to the embodiments of the method for detecting residual oil in a reservoir described above in this application.

[0093] See Figure 5 The diagram shows a block diagram of a reservoir residual oil detection device according to an embodiment of this application. Figure 5 As shown, the reservoir residual oil detection device according to an embodiment of this application includes:

[0094] The survey network determination module 501 is used to determine the survey points and benchmark points of the reservoir;

[0095] The colloid injection module 502 is used to inject a colloid containing magnetoelectric microparticles into the reservoir.

[0096] The magnetic anomaly measurement module 503 is used to obtain the magnetic induction intensity of the measuring point and the base point before and after the colloid injection through the superconducting magnetometer.

[0097] The magnetic anomaly analysis module 504 is used to analyze the magnetic induction intensity of the measuring point and the base point before and after the colloid injection through the data analysis device, and to determine the magnetic change isofield map of the reservoir before and after the colloid injection.

[0098] The remaining oil analysis module 505 is used to determine the remaining oil saturation plane distribution map of the reservoir based on the magnetic change isofield map and the reservoir dynamics understanding. The remaining oil saturation plane distribution map includes the remaining oil boundary distribution characteristics and the water flow dominant channel distribution characteristics of the reservoir.

[0099] In some embodiments of this application, based on the foregoing scheme, an injection device is also provided on the surface of the reservoir. The injection device includes a booster pump, a pressure gauge, and a water injection system. The colloid injection module 502 is also used to inject colloid containing magnetic and electric microparticles into the formation of the water injection well through the injection device.

[0100] In some embodiments of this application, based on the foregoing scheme, the magnetic anomaly analysis module 504 is further configured to analyze the magnetic induction intensity of the measuring point and the base point before and after the colloid injection using the data analysis device, and obtain the change in magnetic induction intensity of the measuring point and the base point before and after the colloid injection; based on the change in magnetic induction intensity, determine the magnetic change isofield map of the reservoir before and after the colloid injection.

[0101] In some embodiments of this application, based on the aforementioned scheme, the remaining oil analysis module 505 is further configured to determine the total magnetic change isofield map, the vertical magnetic change isofield map, and the planar magnetic change isofield map according to the magnetic change isofield map; and to determine the planar distribution map of the remaining oil saturation of the reservoir according to the total magnetic change isofield map, the vertical magnetic change isofield map, the planar magnetic change isofield map, and the reservoir dynamics understanding.

[0102] In some embodiments of this application, based on the aforementioned scheme, the magnetic anomaly measurement module 503 is used to obtain the background magnetic induction intensity of the measuring point and the base point in advance through the superconducting magnetometer; when the background magnetic induction intensity meets the error requirements, the superconducting magnetometer is used to obtain the magnetic induction intensity of the measuring point and the base point before and after the colloid injection.

[0103] In some embodiments of this application, based on the aforementioned scheme, the remaining oil analysis module 505 is further used to determine high-value anomaly regions and micro-magnetic anomaly regions based on the stable magnetic field regions and abnormal magnetic field regions in the magnetic change isofield map; and to determine the remaining oil saturation plane distribution map of the reservoir based on the high-value anomaly regions, micro-magnetic anomaly regions and the reservoir dynamics.

[0104] Based on the same inventive concept, such as Figure 6 As shown in the embodiments of this application, a reservoir residual oil exploration system is also provided. This system includes an analysis system, a retesting unit, and an injection unit. The analysis system, i.e., the aforementioned data analysis device, is used to process and analyze magnetic survey data, and, combined with detailed reservoir geology and development dynamics, to draw a planar distribution map of residual oil saturation. This map intuitively and accurately depicts the planar distribution characteristics of oil and gas, such as residual oil boundaries and water flow dominance channels, thereby guiding the selection of reservoir development methods.

[0105] The aforementioned retesting unit can consist of at least one superconducting magnetometer, used to measure the magnetic anomaly changes caused by the injection of magnetoelectric microparticles into the formation within the reservoir working area, and to obtain the magnetic induction intensity isofield map.

[0106] In some embodiments, the analysis system described above can be integrated with the retesting unit into a single device, such as the magnetic anomaly retesting device or background magnetic anomaly acquisition device described above. Alternatively, they can exist independently.

[0107] The aforementioned injection unit, or injection device, consists of a booster pump, a pressure gauge, a water injection system, etc., and is used to inject magnetoelectric microparticle colloids into the target formation of the water injection well.

[0108] This application also provides an instrument for detecting residual oil in an oil reservoir, as described in the following embodiments. Figure 7 The diagram shows a schematic of the structure of a reservoir residual oil detection device according to an embodiment of this application. The reservoir residual oil detection device includes one or more memories 704, one or more processors 702, and at least one computer program (computer program instructions) stored in the memory 704 and executable on the processor 702. When the processor 702 executes the computer program, it implements the method described above.

[0109] Among them, Figure 7 In this document, a bus architecture (represented by bus 700) is used. Bus 700 may include any number of interconnected buses and bridges, linking various circuits including one or more processors represented by processor 702 and memory represented by memory 704. Bus 700 may also link various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. Bus interface 705 provides an interface between bus 700 and receiver 701 and transmitter 703. Receiver 701 and transmitter 703 may be the same element, i.e., a transceiver, providing a unit for communicating with various other devices over a transmission medium. Processor 702 is responsible for managing bus 700 and general processing, while memory 704 can be used to store data used by processor 702 during operation.

[0110] Based on the same inventive concept, embodiments of this application provide a computer-readable storage medium storing computer program instructions, which, when executed by a processor, cause the processor to perform the steps of the method described above.

[0111] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored as one or more instructions or codes on or transmitted via a computer-readable medium. Other examples and embodiments are within the scope and spirit of this application and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hardwired, or any combination thereof. Furthermore, the functional units may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit.

[0112] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0113] The units described as separate components may or may not be physically separate. Similarly, the components of the control device may or may not be physical units; they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0114] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing computer program instructions, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0115] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc. The aforementioned detection components, processing units, memory, subtractors, comparators, processors, etc., can be considered as hardware components, and the devices included within them for implementing various functions can also be considered as structures within the hardware component. Alternatively, the devices for implementing various functions can be considered as both software modules implementing the method and structures within the hardware component. The components described in this application can be specifically implemented by computer chips or physical entities, or by products with certain functions.

[0116] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for detecting remaining oil in an oil reservoir, characterized in that, A superconducting magnetometer and data analysis device are installed on the surface of the oil reservoir. The method includes: Determine the measuring points and benchmarks of the reservoir; Injecting a colloid containing magnetoelectric microparticles into the reservoir; The magnetic induction intensity of the measuring point and the base point before and after the colloid injection is obtained by the superconducting magnetometer. The data analysis device is used to analyze the magnetic induction intensity of the measuring point and the base point before and after the colloid injection, and to determine the magnetic change isofield map of the reservoir before and after the colloid injection. Based on the magnetic variation isofield map and the reservoir dynamics, the remaining oil saturation plane distribution map of the reservoir is determined. The remaining oil saturation plane distribution map includes the remaining oil boundary distribution characteristics and the water flow dominant channel distribution characteristics of the reservoir.

2. The method for detecting remaining oil in an oil reservoir according to claim 1, characterized in that, An injection device is also installed on the surface of the oil reservoir. The injection device includes a booster pump, a pressure gauge, and a water injection system. The injection of a colloid containing magnetic and electric microparticles into the oil reservoir includes: The injection device injects a colloid containing magnetoelectric particles into the formation of the injection well.

3. The method for detecting remaining oil in an oil reservoir according to claim 1, characterized in that, The step of analyzing the magnetic induction intensity of the measuring points and the base points before and after the colloid injection using the data analysis device to determine the magnetic field map of the reservoir before and after the colloid injection includes: The magnetic induction intensity of the measuring point and the base point before and after the colloid injection is analyzed by the data analysis device to obtain the changes in magnetic induction intensity of the measuring point and the base point before and after the colloid injection. Based on the change in magnetic induction intensity, the magnetic field map of the reservoir before and after the colloid injection is determined.

4. The method for detecting residual oil in a reservoir according to any one of claims 1 to 3, characterized in that, The step of determining the remaining oil saturation planar distribution map of the reservoir based on the magnetic variation isofield map and the reservoir dynamics understanding includes: Based on the magnetic change isofield diagram, determine the total magnetic change isofield diagram, the vertical magnetic change isofield diagram, and the planar magnetic change isofield diagram; Based on the total magnetic variation isofield map, vertical magnetic variation isofield map, planar magnetic variation isofield map, and the reservoir dynamics, the planar distribution map of the remaining oil saturation of the reservoir is determined.

5. The method for detecting residual oil in a reservoir according to any one of claims 1 to 3, characterized in that, The step of obtaining the magnetic induction intensity of the measuring point and the base point before and after the colloid injection using the superconducting magnetometer includes: The background magnetic induction intensity of the measuring point and the base point is obtained in advance using the superconducting magnetometer. When the background magnetic induction intensity meets the error requirements, the magnetic induction intensity of the measuring point and the base point before and after the colloid injection is obtained by the superconducting magnetometer.

6. The method for detecting residual oil in a reservoir according to any one of claims 1 to 3, characterized in that, The step of determining the remaining oil saturation planar distribution map of the reservoir based on the magnetic variation isofield map and the reservoir dynamics understanding includes: Based on the stable magnetic field region and abnormal magnetic field region in the magnetic change isofield diagram, the high-value abnormal region and the micro-magnetic abnormal region are determined. Based on the high-value anomaly region, the micromagnetic anomaly region, and the understanding of reservoir dynamics, a planar distribution map of the remaining oil saturation of the reservoir is determined.

7. A device for detecting residual oil in an oil reservoir, characterized in that, A superconducting magnetometer and data analysis device are installed on the surface of the oil reservoir, including: The survey network determination module is used to determine the survey points and benchmark points of the reservoir; A colloid injection module is used to inject a colloid containing magnetoelectric microparticles into the reservoir. The magnetic anomaly measurement module is used to obtain the magnetic induction intensity of the measuring point and the base point before and after the colloid injection using the superconducting magnetometer. The magnetic anomaly analysis module is used to analyze the magnetic induction intensity of the measuring point and the base point before and after the colloid injection through the data analysis device, and to determine the magnetic change isofield map of the reservoir before and after the colloid injection. The remaining oil analysis module is used to determine the remaining oil saturation plane distribution map of the reservoir based on the magnetic change isofield map and the reservoir dynamics. The remaining oil saturation plane distribution map includes the remaining oil boundary distribution characteristics and the water flow dominant channel distribution characteristics of the reservoir.

8. The reservoir residual oil detection device according to claim 7, characterized in that, An injection device is also installed on the surface of the oil reservoir. The injection device includes a booster pump, a pressure gauge, and a water injection system. The colloid injection module is used to inject a colloid containing magnetic and electric microparticles into the formation of the water injection well through the injection device.

9. A device for detecting residual oil in an oil reservoir, comprising a processor and a memory, characterized in that, The memory stores computer program instructions that can be executed by the processor, and when the processor executes the computer program instructions, it implements the steps of the method as described in any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer program instructions that, when executed by a processor, cause the processor to perform the steps of the method as described in any one of claims 1 to 6.

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