Method and apparatus for determining micro-structured oil reservoir area

Abstract

The present disclosure relates to a method and device for determining a micro-structured oil reservoir area, belonging to the field of micro-structures. The method for determining a micro-structured oil reservoir area includes: determining the depth of the oil-water interface of the micro-structured oil reservoir based on logging data; determining at least one oil well among multiple wells based on the depth of the oil-water interface; determining the seismic reflection time of the top interface and the seismic reflection time of the bottom interface of at least one well based on the seismic data and logging data of at least one well among the at least one oil well; determining the top interface seismic time slice and the bottom interface seismic time slice of at least one well based on the seismic data, the seismic reflection time of the top interface and the seismic reflection time of the bottom interface of at least one well; determining the top interface structural contour map of the micro-structured oil reservoir based on the top interface seismic time slice and the bottom interface seismic time slice; and determining the reservoir area of the micro-structured oil reservoir based on the top interface structural contour map and the depth of the oil-water interface.

Description

Technical Field

[0001] The present disclosure relates to the field of microstructures, and particularly to a method and device for determining the reservoir area of a microstructured oil layer. Background Art

[0002] A micro-structure refers to the structural features shown by the undulations of a formation. Micro-structures include positive micro-structures and negative micro-structures. A positive micro-structure refers to a structure where the formation is relatively uplifted, and a negative micro-structure refers to a structure where the formation is relatively depressed.

[0003] A micro-structured oil layer refers to an oil layer with micro-structural features. In the middle and late stages of oilfield exploitation, in order to reasonably arrange the positions of remaining wells, it is necessary to determine the reservoir area of the micro-structured oil layer, and then determine the positions of the remaining wells according to the positions of the reservoir areas of the micro-structured oil layers.

[0004] In the related art, the method for determining the reservoir area of a micro-structured oil layer includes: performing horizon calibration on the entire oilfield production area based on well logging curves and seismic wave curves; carrying out fine structural interpretation of the entire oilfield production area based on the results of horizon calibration by tracking seismic event axes; performing time-depth conversion and structure mapping on the micro-structured oil layer based on the results of the fine structural interpretation of the entire oilfield production area; determining the isobath map of the micro-structured oil layer based on the results of the time-depth conversion and structure mapping of the micro-structured oil layer; and determining the reservoir area of the micro-structured oil layer based on the isobath map of the micro-structured oil layer. However, this method requires horizon calibration for the entire oilfield production area, which is labor-intensive and time-consuming. Summary of the Invention

[0005] Embodiments of the present disclosure provide a method and device for determining the reservoir area of a micro-structured oil layer. The technical solutions are as follows:

[0006] On the one hand, the present disclosure provides a method for determining the reservoir area of a micro-structured oil layer. The micro-structured oil layer is located in an oilfield production area, and the oilfield production area includes multiple wells, all of which penetrate the micro-structured oil layer. The method for determining the reservoir area of the micro-structured oil layer includes: based on well logging data, determining the depth of the oil-water interface of the micro-structured oil layer; based on the depth of the oil-water interface, determining at least one oil well among the multiple wells, where the bottom interface depth of the micro-structured oil layer in each of the at least one oil well is greater than the depth of the oil-water interface; based on the seismic data and well logging data of at least one well among the at least one oil well, determining the top interface seismic reflection time and the bottom interface seismic reflection time of the at least one well; based on the seismic data of the at least one well, the top interface seismic reflection time, and the bottom interface seismic reflection time, determining the top interface seismic time slice and the bottom interface seismic time slice of the at least one well, where the top interface seismic time slice of the at least one well is used to reflect the seismic imaging of the micro-structured oil layer at the top interface seismic reflection time, and the bottom interface seismic time slice of the at least one well is used to reflect the seismic imaging of the micro-structured oil layer at the bottom interface seismic reflection time; based on the top interface seismic time slice and the bottom interface seismic time slice, determining the top interface structural contour map of the micro-structured oil layer; based on the top interface structural contour map and the depth of the oil-water interface, determining the reservoir area of the micro-structured oil layer.

[0007] In one implementation manner of the embodiment of the present disclosure, based on the seismic data and well logging data of at least one well among the at least one oil well, determining the top interface seismic reflection time and the bottom interface seismic reflection time of the at least one well includes: based on the seismic data and well logging data of at least one well among the at least one oil well, determining the time-depth relationship diagram of the at least one well, where the time-depth relationship diagram includes well logging data in the depth domain, a seismic record synthesized from the well logging data, and an original seismic record in the time domain; reading the top interface seismic reflection time and the bottom interface seismic reflection time of the at least one well from the time-depth relationship diagram.

[0008] In one implementation manner of the embodiment of the present disclosure, based on the top interface seismic time slice and the bottom interface seismic time slice, determining the top interface structural contour map of the micro-structured oil layer includes: marking the top interface depth structural line of each well among the multiple wells in the top interface seismic time slice; drawing depth contour lines in the top interface seismic time slice marked with the top interface depth structural line of each well to obtain the top interface structural contour map of the micro-structured oil layer.

[0009] In one implementation of the embodiments of the present disclosure, determining the reservoir area of the micro-structural oil layer based on the top interface structure contour map and the depth of the oil-water interface includes: identifying the structural line of the depth of the oil-water interface in the top interface structure contour map; determining the area enclosed by the structural line of the depth of the oil-water interface as the reservoir area of the micro-structural oil layer.

[0010] In one implementation of the embodiments of the present disclosure, the method further includes: determining the average thickness of the micro-structural oil layer based on the logging data of each of the at least one oil well; determining the reservoir area of the micro-structural oil layer based on the reservoir area of the micro-structural oil layer; obtaining the single storage coefficient of the micro-structural oil layer based on the logging data; and determining the reserves of the micro-structural oil layer based on the average thickness, the reservoir area, and the single storage coefficient.

[0011] In one implementation of the embodiments of the present disclosure, determining the average thickness of the micro-structural oil layer based on the logging data of each of the at least one oil well includes: obtaining the top interface depth and the bottom interface depth of each oil well in the at least one oil well based on the logging data; determining the thickness of the micro-structural oil layer in each oil well based on the top interface depth and the bottom interface depth of each oil well; and taking the average value of the thicknesses of the micro-structural oil layers in each oil well in the at least one oil well as the average thickness of the micro-structural oil layer.

[0012] In one implementation of the embodiments of the present disclosure, the method further includes: determining a cross-well seismic profile based on the seismic data, where the cross-well includes the multiple wells; and determining the positive micro-structural area of the micro-structural oil layer based on the top interface seismic time slice, the bottom interface seismic time slice, and the cross-well seismic profile.

[0013] In one implementation of the embodiments of the present disclosure, the actual depth between two adjacent depth contour lines in the top interface structure contour map of the micro-structural oil layer is between 2 meters and 4 meters.

[0014] On the other hand, the present disclosure provides an apparatus for determining the reservoir area of a micro-structured oil layer. The micro-structured oil layer is located in an oilfield exploitation area, and the oilfield exploitation area includes multiple wells, all of which penetrate the micro-structured oil layer. The apparatus for determining the reservoir area of the micro-structured oil layer includes: a first determination module configured to determine the depth of the oil-water interface of the micro-structured oil layer based on well logging data; a second determination module configured to determine at least one oil well among the multiple wells, where the bottom interface depth of the micro-structured oil layer in each of the at least one oil well is greater than the depth of the oil-water interface; a third determination module configured to determine the top interface seismic reflection time and the bottom interface seismic reflection time of the at least one well based on the seismic data and well logging data of at least one well among the at least one oil well; a fourth determination module configured to determine the top interface seismic time slice and the bottom interface seismic time slice of the at least one well based on the seismic data of the at least one well, the top interface seismic reflection time, and the bottom interface seismic reflection time. The top interface seismic time slice of the at least one well is used to reflect the seismic imaging of the micro-structured oil layer at the top interface seismic reflection time, and the bottom interface seismic time slice of the at least one well is used to reflect the seismic imaging of the micro-structured oil layer at the bottom interface seismic reflection time; a fifth determination module configured to determine the top interface structural contour map of the micro-structured oil layer based on the top interface seismic time slice and the bottom interface seismic time slice; a sixth determination module configured to determine the reservoir area of the micro-structured oil layer based on the top interface structural contour map and the depth of the oil-water interface.

[0015] In one implementation of the embodiments of the present disclosure, the third determination module is configured to: determine the time-depth relationship diagram of the at least one well based on the seismic data and well logging data of at least one well among the at least one oil well. The time-depth relationship diagram includes well logging data in the depth domain, a seismic record synthesized from the well logging data, and an original seismic record in the time domain; read the top interface seismic reflection time and the bottom interface seismic reflection time of the at least one well from the time-depth relationship diagram.

[0016] The beneficial effects brought by the technical solutions provided in the embodiments of the present disclosure at least include:

[0017] In the method for determining the micro-structured oil reservoir area provided by the present disclosure, since at least one oil well among the multiple wells determined first by the method provided by the present disclosure must pass through the micro-structured oil reservoir area, only the structural analysis of the oil wells needs to be carried out. For example, the structural analysis of one of the oil wells is carried out to obtain the seismic time slice of the top interface and the seismic time slice of the bottom interface of this oil well, and then the top interface structural contour map of the micro-structured oil reservoir is determined based on the seismic time slice of the top interface and the seismic time slice of the bottom interface. Compared with the time-depth conversion and structure mapping of the micro-structured oil reservoir by the fine interpretation of the structure in the oil field exploitation area, the workload is less and the work efficiency is high. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the accompanying drawings required for the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, other accompanying drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 is a flowchart of a method for determining the micro-structured oil reservoir area provided by an embodiment of the present disclosure;

[0020] Figure 2 is a flowchart of a method for determining the micro-structured oil reservoir area provided by an embodiment of the present disclosure;

[0021] Figure 3 is a well reservoir profile diagram provided by an embodiment of the present disclosure;

[0022] Figure 4 is a well synthetic seismogram calibration diagram provided by an embodiment of the present disclosure;

[0023] Figure 5 is a top interface seismic time slice diagram provided by an embodiment of the present disclosure;

[0024] Figure 6 is a bottom interface seismic time slice diagram provided by an embodiment of the present disclosure;

[0025] Figure 7 is a cross-well seismic profile provided by an embodiment of the present disclosure;

[0026] Figure 8 is a top interface structural depth contour map provided by an embodiment of the present disclosure;

[0027] Figure 9 is a bottom interface structural depth contour map provided by an embodiment of the present disclosure;

[0028] Figure 10It is an isogram of the surface texture depth provided by an embodiment of the present disclosure;

[0029] Figure 11 It is an oil-bearing range map of an oil reservoir provided by an embodiment of the present disclosure;

[0030] Figure 12 It is a block diagram of a device for determining the oil reservoir area of a microstructural oil layer provided by an embodiment of the present disclosure. Detailed implementation manners

[0031] To make the objectives, technical solutions, and advantages of the present disclosure clearer, the following will further describe the embodiments of the present disclosure in detail with reference to the accompanying drawings.

[0032] Figure 1 It is a flowchart of a method for determining the oil reservoir area of a microstructural oil layer provided by an embodiment of the present disclosure. The microstructural oil layer is located in the oilfield exploitation area, and the oilfield exploitation area includes multiple wells, and all the multiple wells pass through the microstructural oil layer. Refer to Figure 1 , the method for determining the oil reservoir area of the microstructural oil layer includes:

[0033] In step S101, based on the logging data, determine the depth of the oil-water interface of the microstructural oil layer.

[0034] In the embodiment of the present disclosure, before well exploitation, logging is first performed to better understand the characteristics of the underground oil layer, so as to obtain logging data, and then the depth of the oil-water interface of the microstructural oil layer is determined from the logging data.

[0035] Exemplarily, the logging data includes an amplitude curve, an acoustic travel time curve, a resistivity curve, etc.

[0036] In step S102, based on the depth of the oil-water interface, determine at least one oil well among the multiple wells, and the bottom interface depth of the microstructural oil layer in each of the at least one oil well is greater than the depth of the oil-water interface.

[0037] In the embodiment of the present disclosure, the well with the bottom interface depth greater than the depth of the oil-water interface in the well is determined as an oil well to ensure that there is an oil reservoir in the oil well, and the well with only water is excluded to reduce subsequent operations.

[0038] In step S103, based on the seismic data and logging data of at least one well among the at least one oil well, determine the top interface seismic reflection time and the bottom interface seismic reflection time of the at least one oil well.

[0039] In the embodiment of the present disclosure, before well exploitation, seismic data acquisition is performed to obtain seismic data.

[0040] Exemplarily, the seismic data includes seismic waves, seismic profiles, seismic time slices, etc.

[0041] In an embodiment of the present disclosure, by synthesizing the seismic data and logging data of an oil well in seismic analysis software, a time-depth conversion map of the oil well can be obtained, and from the time-depth conversion map, the seismic reflection time of the top interface and the seismic reflection time of the bottom interface of the oil well can be obtained.

[0042] Exemplarily, the seismic analysis software includes Landmark, Geoeast, etc.

[0043] In step S104, based on the seismic data, the seismic reflection time of the top interface, and the seismic reflection time of the bottom interface of at least one well, the seismic time slice of the top interface and the seismic time slice of the bottom interface of at least one well are determined.

[0044] In an embodiment of the present disclosure, the seismic time slice of the top interface of at least one well is used to reflect the seismic imaging of the microstructural oil reservoir at the seismic reflection time of the top interface, and the seismic time slice of the bottom interface of at least one well is used to reflect the seismic imaging of the microstructural oil reservoir at the seismic reflection time of the bottom interface. According to the seismic reflection time of the top interface and the seismic reflection time of the bottom interface, the seismic time slice of the top interface and the seismic time slice of the bottom interface of the oil well can be extracted from the seismic data of the oil well through seismic analysis software.

[0045] In step S105, based on the seismic time slice of the top interface and the seismic time slice of the bottom interface, the top interface structure isopach map of the microstructural oil reservoir is determined.

[0046] In an embodiment of the present disclosure, by drawing depth contour lines in the seismic time slice of the top interface, the top interface structure isopach map of the microstructural oil reservoir can be obtained.

[0047] In step S106, based on the top interface structure isopach map and the depth of the oil-water interface, the reservoir area of the microstructural oil reservoir is determined.

[0048] In the method for determining the reservoir area of the microstructural oil reservoir provided by the present disclosure, since at least one oil well among the multiple wells determined first by the method provided by the present disclosure must pass through the reservoir area of the microstructural oil reservoir, then only the structural analysis of the oil wells needs to be carried out. For example, the structural analysis of one of the oil wells is carried out to obtain the seismic time slice of the top interface and the seismic time slice of the bottom interface of this oil well, and then based on the seismic time slice of the top interface and the seismic time slice of the bottom interface, the top interface structure isopach map of the microstructural oil reservoir is determined. Compared with the time-depth conversion and structure mapping of the microstructural oil reservoir by the fine interpretation of the structure in the oilfield production area, the workload is less and the work efficiency is higher.

[0049] Figure 2 It is a flowchart of a method for determining the reservoir area of a microstructural oil reservoir provided by an embodiment of the present disclosure.

[0050] See Figure 2 , the method includes:

[0051] In step 201, based on well logging data, obtain the top interface depth and bottom interface depth of the microstructural oil layer in each of multiple wells.

[0052] In the embodiments of the present disclosure, the depth values of the top interface and bottom interface of the microstructural oil layer in each well will be marked in the well logging data of each well, and the numerical value of the top interface depth and the numerical value of the bottom interface depth of the microstructural oil layer in this well can be directly read from the well logging data.

[0053] The following explains the method for determining the reservoir area of the microstructural oil layer of the present disclosure according to an embodiment, taking the target reservoir B1 in the XX well area of the Gangdong Development Zone in the Huanghua Depression as an example:

[0054] Exemplary embodiment: Select multiple wells W1, W2, W3, W4,..., W8 in the work area, and draw a reservoir profile for the target reservoir B1. Figure 3 This is a well reservoir profile provided by the embodiments of the present disclosure. Refer to Figure 3 , the target reservoir B1 is relatively uplifted, and the B1 reservoir is a positive micro-structure. Since it has been determined that the part of the B1 reservoir passing through W1, W2, W3, and W4 is a positive micro-structure, so Figure 3 only W1, W2, W3, and W4 are shown; the top boundary structural depths of the B1 layer of W1, W2, W3, W4,..., W8 are -3370m, -3340m, -3354m, -3377m,..., -3402m respectively, and the bottom boundary structural depths are -3379m, -3348m, -3363m, -3386m,..., -3410m.

[0055] In step 202, determine the oil-water interface depth of the microstructural oil layer based on the oil depth and water depth of the first well. The first well belongs to multiple wells, and the oil-water interface of the microstructural oil layer passes through the first well.

[0056] Since the density of crude oil is less than that of water, in the microstructural oil layer, crude oil is located in the upper part of the microstructural oil layer and water is located in the lower part of the microstructural oil layer, so there will be an oil-water interface. When the oil-water interface passes through the first well, the oil-water interface depth of the microstructural oil layer can be directly read from the well logging data of the first well.

[0057] Exemplary embodiment: Determine that the oil-water interface of the B1 reservoir is -3376m according to the top oil (-3370m to -3376m) and bottom water (-3376m to -3379m) of Well W1, that is, Well W1 is the first well.

[0058] In step 203, determine at least one oil well among multiple wells based on the oil-water interface depth, top interface depth, and bottom interface depth.

[0059] In the embodiments of the present disclosure, the depth of the bottom interface of the micro-structured oil layer in the oil well is greater than the depth of the oil-water interface, so as to ensure that there is crude oil in the determined oil wells and eliminate the wells that only contain water, thus simplifying the subsequent steps.

[0060] Exemplary embodiment: Select the wells above the oil-water interface of Reservoir B1, such as: W2, W3, W4.

[0061] In step 204, based on the seismic data and logging data of at least one well among at least one oil well, a time-depth relationship diagram of at least one well is determined.

[0062] In the embodiments of the present disclosure, the time-depth relationship diagram includes logging data in the depth domain, seismic records synthesized from the logging data, and the original seismic records in the time domain;

[0063] Exemplarily, the time-depth relationship diagram includes an amplitude curve, an acoustic wave transit time curve, a resistivity curve, and seismic waves.

[0064] Exemplarily, by inputting the seismic data and logging data of the oil well into seismic analysis software for time-depth conversion, the time-depth relationship diagram of the oil well can be obtained.

[0065] Exemplary embodiment: Select oil-containing wells (such as W2, W3, etc.) to produce synthetic seismic records in the seismic analysis software, and complete the calibration of the synthetic records based on the principle that the single-well synthetic record of the target reservoir B1 is similar to the seismic trace beside the well. Figure 4 It is a well synthetic record calibration diagram provided by the embodiments of the present disclosure, that is Figure 4 is the time-depth relationship diagram.

[0066] In step 205, the seismic reflection time of the top interface and the seismic reflection time of the bottom interface of at least one well are read from the time-depth relationship diagram.

[0067] Exemplarily, the seismic reflection time of the top interface and the seismic reflection time of the bottom interface will be displayed in the time-depth relationship diagram of the seismic analysis software, and the seismic reflection time of the top interface and the seismic reflection time of the bottom interface of the oil well can be directly read.

[0068] Exemplary embodiment: Refer to Figure 4 , according to the layer calibration result, the seismic reflection time of the top interface and the seismic reflection time of the bottom interface of the target reservoir B1 are read as 2618 ms and 2630 ms.

[0069] In step 206, based on the seismic data, the seismic reflection time of the top interface, and the seismic reflection time of the bottom interface of at least one well, the seismic time slice of the top interface and the seismic time slice of the bottom interface of at least one well are determined.

[0070] In the embodiments of the present disclosure, by inputting the seismic reflection time of the top interface and the seismic reflection time of the bottom interface of the oil well into the above-mentioned seismic analysis software, the seismic time slice of the top interface and the seismic time slice of the bottom interface can be extracted.

[0071] In the related art, each well in the oilfield exploitation area needs to be analyzed through seismic analysis software, while the method provided by the embodiments of the present disclosure only needs to analyze the oil well, reducing the workload and improving the work efficiency.

[0072] Optionally, the method further includes: determining a cross-well seismic profile based on seismic data, where the cross-well includes multiple wells. Based on the seismic time slice of the top interface, the seismic time slice of the bottom interface, and the cross-well seismic profile, determining the positive microstructural area of the microstructural oil layer. Among them, the multiple wells are all the wells in the oilfield exploitation area.

[0073] Exemplarily, through the above-mentioned seismic analysis software, a cross-well profile can be extracted from seismic data.

[0074] Since in the microstructural oil layer, the crude oil is located in the upper part of the microstructural oil layer and the water is located in the lower part of the microstructural oil layer, only the positive microstructural area contains crude oil, while the negative microstructural area does not contain crude oil. Therefore, it is necessary to determine the positive microstructural area of the microstructural oil layer.

[0075] In the embodiments of the present disclosure, the microstructural area of the microstructural oil layer can be determined according to the seismic time slice of the top interface and the seismic time slice of the bottom interface. The microstructural area is the middle area between the seismic time slice of the top interface and the seismic time slice of the bottom interface, but it is impossible to determine whether this area is a positive microstructural area or a negative microstructural area. It is necessary to combine the cross-well seismic profile to determine the positive microstructural area. In the cross-well seismic profile, the positive microstructural area is determined according to the trend of the microstructural oil layer. The area where the microstructural oil layer bulges is the positive microstructural area.

[0076] Exemplary embodiment: Extract the seismic time (2618 ms) slice A1 of the top interface of the target oil reservoir B1, Figure 5 which is a seismic time slice diagram of the top interface provided by the embodiments of the present disclosure. Extract the seismic time (2630 ms) slice A2 of the bottom interface of the target oil reservoir B1, Figure 6 which is a seismic time slice diagram of the bottom interface provided by the embodiments of the present disclosure. Make a cross-well seismic profile passing through W1, W2, W3, and W4, Figure 7 which is a cross-well seismic profile provided by the embodiments of the present disclosure. Refer to Figure 7 , W1 to W4 develop positive microstructures, and the vicinity of W2 is the microstructural high point. At this time, from Figures 5 to 7 , the seismic characteristics of this structure show that the isophase axis rolls outwards.

[0077] In step 207, identify the top interface depth structure lines of each well among multiple wells in the top interface seismic time slice.

[0078] If the top interface depth of the micro-structured oil layer in the oil well is less than the oil-water interface depth of the micro-structured oil layer, it indicates that the oil well contains crude oil. Therefore, it is necessary to identify the top interface depth of the oil well in the top interface seismic time slice to form the top interface depth structure line, which is convenient for subsequent comparison with the oil-water interface depth.

[0079] Among them, the top interface depth refers to the distance from the ground to the top interface, and the oil-water interface depth refers to the distance from the ground to the oil-water interface. If the top interface depth of the micro-structured oil layer in the oil well is less than the oil-water interface depth of the micro-structured oil layer, it indicates that the top interface of the micro-structured oil layer in the oil well is above the oil-water interface depth of the micro-structured oil layer.

[0080] In the embodiment of the present disclosure, by inputting the top interface depth of each well among multiple wells into the above-mentioned seismic analysis software, the top interface depth structure line of each well can be obtained.

[0081] Exemplary embodiment: Outline the structural isobaths according to the trend of seismic event axes. For wells W1, W2, W3, W4,..., W8 in the work area, mark the top depth of B1 of each well in the top interface seismic time slice diagram and the bottom depth of B1 in the bottom interface seismic time slice diagram. Determine the depth contour closed curve according to the trend of the seismic event axes, and draw the B1 top interface structural depth contour map passing through wells W1 - W8. Figure 8 It is a top interface structural depth contour map provided by the embodiment of the present disclosure. Draw the B1 bottom interface structural depth contour map passing through wells W1 - W8. Figure 9 It is a bottom interface structural depth contour map provided by the embodiment of the present disclosure. Since the thickness of layer B1 is stable, therefore Figure 8 The morphological reference of the structural line in the high-middle part Figure 9 .

[0082] See Figure 8 , the depth contour of -3370m passes through well W1, the depth contour of -3340m passes through well W2, the depth contour of -3354m passes through well W3, the depth contour of -3377m passes through well W4, the depth contour of -3402m passes through well W5, the depth contour of -3370m passes through well W6, the depth contour of -3354m passes through well W7, and well W8 is near the depth contour of -3402m.

[0083] See Figure 9, the depth contour line of -3379m passes through Well W1, the depth contour line of -3354m passes through Well W2, the depth contour line of -3363m passes through Well W3, the depth contour line of -3386m passes through Well W4, the depth contour line of -3410m passes through Well W5, the depth contour line of -3379m passes through Well W6, Well W7 is near the depth contour line of -3354m, and Well W8m is near the depth contour line of -3402.

[0084] In step 208, depth contour lines are drawn in the top surface seismic time slice marked with the top surface depth structure lines of each well to obtain the top surface structure depth contour map of the micro-structured oil reservoir. The depths of the points on the same depth contour line are the same.

[0085] In the embodiments of the present disclosure, the difference in the top surface depths of each well is generally large. In order to reduce the error of the determined oil reservoir area in the subsequent process, it is necessary to draw depth contour lines in the top surface seismic time slice to obtain the top surface structure depth contour map of the micro-structured oil reservoir.

[0086] Exemplarily, by inputting the depth values of the depth contour lines to be drawn into the seismic analysis software, the depth contour lines can be drawn.

[0087] Exemplarily, the actual depth difference between two adjacent depth contour lines in the top surface structure contour map of the micro-structured oil reservoir is between 2 meters and 4 meters.

[0088] Exemplary embodiment: On the Figure 8 basis, the depth contour lines are uniformly interpolated and encrypted at a spacing of 4m to generate the top surface structure depth contour map of B1, Figure 10 which is the top surface structure depth contour map provided by the embodiments of the present disclosure.

[0089] In step 209, the structure line indicating the oil-water interface depth is marked in the top surface structure contour map.

[0090] In the embodiments of the present disclosure, in order to facilitate the comparison between the top surface depth of the oil well and the structure line of the oil-water interface depth, it is necessary to mark the structure line of the oil-water interface depth in the top surface structure contour map.

[0091] In the embodiments of the present disclosure, by inputting the oil-water interface depth into the above-mentioned seismic analysis software, the structure line of the oil-water interface depth can be marked in the top surface structure contour map.

[0092] Exemplarily, for the convenience of distinction, the color of the structure line of the oil-water interface depth can be made different from the color of the top surface depth structure line of the oil well.

[0093] In step 210, the area enclosed by the structure line of the oil-water interface depth is used as the oil reservoir area of the micro-structured oil reservoir.

[0094] In the embodiments of the present disclosure, the part above the oil-water interface depth of the micro-structured oil layer is all crude oil. The structural line at the oil-water interface depth is a closed curve, and the depth of the part located within the closed curve is less than the oil-water interface depth. The area enclosed by the structural line at the oil-water interface depth is used as the reservoir area of the micro-structured oil layer.

[0095] Exemplary embodiment: According to the determined oil-water interface of reservoir B1 being -3376m, the range greater than -3376m is marked out. Figure 11 It is an oil-bearing range map of a reservoir provided by the embodiments of the present disclosure. Refer to Figure 11 , and the oil-bearing range of reservoir B1 is determined ( Figure 11 the area enclosed by the white depth isoline in

[0096] In step 211, the reservoir area of the micro-structured oil layer is determined based on the reservoir area of the micro-structured oil layer.

[0097] In the embodiments of the present disclosure, the area of the reservoir area of the micro-structured oil layer will be displayed in the top interface structure isoline map in the seismic analysis software, and the area of the reservoir area of the micro-structured oil layer can be directly read out. This area is the reservoir area of the micro-structured oil layer.

[0098] In step 212, the single-well storage coefficient of the micro-structured oil layer is obtained based on well logging data.

[0099] Among them, the geological reserves contained in the unit volume of the oil layer in the reservoir is the single-well storage coefficient. The single-well storage coefficient is usually expressed by the crude oil reserves contained in each square kilometer area of each meter of the oil layer, and the single-well storage coefficient of the micro-structured oil layer can be directly obtained from well logging data.

[0100] In step 213, based on the well logging data of each well in at least one oil well, the average thickness of the micro-structured oil layer is determined.

[0101] In step S201, the top interface depth and bottom interface depth of the micro-structured oil layer in each oil well have been determined; then based on the top interface depth and bottom interface depth, the thickness of the micro-structured oil layer in each oil well is determined; and then the average value of the thicknesses of the micro-structured oil layers in each oil well is used as the average thickness of the micro-structured oil layer.

[0102] Among them, the thickness of the micro-structured oil layer in the oil well is equal to the bottom interface depth of the micro-structured oil layer in the oil well minus the bottom interface depth of the micro-structured oil layer in the oil well.

[0103] Exemplary embodiment: Wells above the oil-water interface of reservoir B1 are selected (such as W2, W3, W4,...), the thickness of the oil-bearing layer B1 in each well is statistically averaged, and the average oil layer thickness of reservoir B1 is calculated to be 8.5m.

[0104] In step 214, the reserves of the microstructural oil layer are determined based on the average thickness, reservoir area, and single-well storage coefficient.

[0105] In the embodiments of the present disclosure, the volume of the reservoir can be obtained based on the average thickness and reservoir area, and the reserves of the microstructural oil layer can be obtained by multiplying the volume of the reservoir by the single-well storage coefficient.

[0106] According to the scale, the oil-bearing area of Reservoir B1 is calculated to be 2.1 km 2 , the oil layer thickness is 8.5 m. By referring to the single-well storage coefficient of Reservoir B1, the geological reserves of Reservoir B1 are obtained according to 2.6×8.5×single-well storage coefficient.

[0107] Figure 12 It is a block diagram of a device for determining the reservoir area of a microstructural oil layer provided by the embodiments of the present disclosure. The microstructural oil layer is located in the oilfield exploitation area, and the oilfield exploitation area includes multiple wells, and all the multiple wells pass through the microstructural oil layer. Refer to Figure 12 , the device for determining the reservoir area of the microstructural oil layer includes:

[0108] The first determination module 401 is configured to determine the depth of the oil-water interface of the microstructural oil layer based on well logging data.

[0109] The second determination module 402 is configured to determine at least one oil well among the multiple wells based on the depth of the oil-water interface, and the bottom interface depth of the microstructural oil layer in each of at least one oil well is greater than the depth of the oil-water interface.

[0110] The third determination module 403 is configured to determine the top interface seismic reflection time and the bottom interface seismic reflection time of at least one well based on the seismic data and well logging data of at least one well among at least one oil well.

[0111] The fourth determination module 404 is configured to determine the top interface seismic time slice and the bottom interface seismic time slice of at least one well based on the seismic data, the top interface seismic reflection time, and the bottom interface seismic reflection time of at least one well. The top interface seismic time slice of at least one well is used to reflect the seismic imaging of the microstructural oil layer at the top interface seismic reflection time, and the bottom interface seismic time slice of at least one well is used to reflect the seismic imaging of the microstructural oil layer at the bottom interface seismic reflection time.

[0112] The fifth determination module 405 is configured to determine the top interface structural contour map of the microstructural oil layer based on the top interface seismic time slice and the bottom interface seismic time slice.

[0113] The sixth determination module 406 is configured to determine the reservoir area of the microstructural oil layer based on the top interface structural contour map and the depth of the oil-water interface.

[0114] In an embodiment of the present disclosure, the third determination module 403 is configured to: determine a time-depth relationship diagram of at least one well based on seismic data and logging data of at least one well in at least one oil well, where the time-depth relationship diagram includes logging data in the depth domain, a seismic record synthesized from the logging data, and an original seismic record in the time domain; read the top interface seismic reflection time and the bottom interface seismic reflection time of at least one well from the time-depth relationship diagram.

[0115] In an embodiment of the present disclosure, the fifth determination module 405 is configured to: identify the top interface depth structure line of each well among multiple wells in the top interface seismic time slice; draw depth contour lines in the top interface seismic time slice with the top interface depth structure line of each well marked, to obtain the top interface structure contour map of the micro-structured oil layer.

[0116] In an embodiment of the present disclosure, the sixth determination module 406 is configured to: identify the structure line of the oil-water interface depth in the top interface structure contour map; determine the reservoir area of the micro-structured oil layer as the area enclosed by the structure line of the oil-water interface depth.

[0117] Optionally, the apparatus for determining the reservoir area of the micro-structured oil layer further includes: a seventh determination module 407, configured to determine the average thickness of the micro-structured oil layer based on the logging data of each oil well in at least one oil well; determine the reservoir area of the micro-structured oil layer based on the reservoir area of the micro-structured oil layer; obtain the single reservoir coefficient of the micro-structured oil layer based on the logging data; determine the reserves of the micro-structured oil layer based on the average thickness, the reservoir area, and the single reservoir coefficient.

[0118] In an embodiment of the present disclosure, the seventh determination module 407 is further configured to: obtain the top interface depth of each oil well and the bottom interface depth of each oil well based on the logging data of each oil well; determine the thickness of the micro-structured oil layer in each oil well based on the top interface depth and the bottom interface depth of each oil well; take the average value of the thicknesses of the micro-structured oil layers in each oil well among at least one oil well as the average thickness of the micro-structured oil layer.

[0119] The apparatus for determining the reservoir area of the micro-structured oil layer further includes: an eighth determination module 408, configured to: determine a cross-well seismic profile based on the seismic data, where the cross-well includes the multiple wells; determine the positive micro-structure area of the micro-structured oil layer based on the top interface seismic time slice, the bottom interface seismic time slice, and the cross-well seismic profile.

[0120] The above are only optional embodiments of the present disclosure and are not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included within the protection scope of the present disclosure.

Claims

1. A method for determining the reservoir area of a micro-structured oil layer. The micro-structured oil layer is located in the oilfield production area, and the oilfield production area includes multiple wells, all of which penetrate the micro-structured oil layer. Characterized in that, The method for determining the reservoir area of the micro-structured oil layer includes: Based on well logging data, determine the depth of the oil-water interface of the micro-structured oil layer; Based on the depth of the oil-water interface, determine at least one oil well among the multiple wells, and the bottom interface depth of the micro-structured oil layer in each of the at least one oil well is greater than the depth of the oil-water interface; Based on the seismic data and well logging data of at least one well among the at least one oil well, determine the top interface seismic reflection time and the bottom interface seismic reflection time of the at least one well; Based on the seismic data of the at least one well, the top interface seismic reflection time and the bottom interface seismic reflection time, determine the top interface seismic time slice and the bottom interface seismic time slice of the at least one well. The top interface seismic time slice of the at least one well is used to reflect the seismic imaging of the micro-structured oil layer at the top interface seismic reflection time, and the bottom interface seismic time slice of the at least one well is used to reflect the seismic imaging of the micro-structured oil layer at the bottom interface seismic reflection time; Based on the top interface seismic time slice and the bottom interface seismic time slice, determine the top interface structural contour map of the micro-structured oil layer; Based on the top interface structural contour map and the depth of the oil-water interface, determine the reservoir area of the micro-structured oil layer; Based on the well logging data of each of the at least one oil well, determine the average thickness of the micro-structured oil layer; Based on the reservoir area of the micro-structured oil layer, determine the reservoir area of the micro-structured oil layer; Based on the well logging data, obtain the single reservoir coefficient of the micro-structured oil layer; Based on the average thickness, the reservoir area and the single reservoir coefficient, determine the reserves of the micro-structured oil layer.

2. The method for determining the reservoir area of the micro-structured oil layer according to claim 1, Characterized in that, Based on the seismic data and well logging data of at least one well among the at least one oil well, determining the top interface seismic reflection time and the bottom interface seismic reflection time of the at least one well includes: Based on the seismic data and well logging data of at least one well among the at least one oil well, determine the time-depth relationship diagram of the at least one well. The time-depth relationship diagram includes well logging data in the depth domain, a seismic record synthesized from the well logging data, and an original seismic record in the time domain; Read the top interface seismic reflection time and the bottom interface seismic reflection time of the at least one well from the time-depth relationship diagram.

3. The method for determining the reservoir area of the micro-structured oil layer according to claim 1 or 2, Characterized in that, Based on the top interface seismic time slice and the bottom interface seismic time slice, determining the top interface structural contour map of the micro-structured oil layer includes: Mark the top interface depth structure line of each well among the multiple wells in the top interface seismic time slice; Draw depth contour lines in the top interface seismic time slice marked with the depth structure lines of the top interface of each well to obtain the top interface structure contour map of the micro-structured oil reservoir.

4. The method for determining the oil reservoir area of the micro-structured oil reservoir according to claim 1 or 2, wherein, determining the oil reservoir area of the micro-structured oil reservoir based on the top interface structure contour map and the depth of the oil-water interface includes: marking the structure line of the depth of the oil-water interface in the top interface structure contour map; determining the area enclosed by the structure line of the depth of the oil-water interface as the oil reservoir area of the micro-structured oil reservoir.

5. The method for determining the oil reservoir area of the micro-structured oil reservoir according to claim 1 or 2, wherein, determining the average thickness of the micro-structured oil reservoir based on the logging data of each well in the at least one oil well includes: based on the logging data of each well, obtaining the top interface depth and the bottom interface depth of each well; based on the top interface depth and the bottom interface depth of each well, determining the thickness of the micro-structured oil reservoir in each well; taking the average value of the thicknesses of the micro-structured oil reservoirs in each well of the at least one oil well as the average thickness of the micro-structured oil reservoir.

6. The method for determining the oil reservoir area of the micro-structured oil reservoir according to claim 1 or 2, wherein, the method further includes: determining a cross-well seismic profile based on the seismic data, the cross-well including the multiple wells; determining the positive micro-structure area of the micro-structured oil reservoir based on the top interface seismic time slice, the bottom interface seismic time slice and the cross-well seismic profile.

7. The method for determining the oil reservoir area of the micro-structured oil reservoir according to claim 1 or 2, wherein, the actual depth between two adjacent depth contour lines in the top interface structure contour map of the micro-structured oil reservoir is between 2 meters and 4 meters.

8. An apparatus for determining the oil reservoir area of a micro-structured oil reservoir, the micro-structured oil reservoir is located in an oilfield production area, the oilfield production area includes multiple wells, and the multiple wells all pass through the micro-structured oil reservoir, wherein, the apparatus for determining the oil reservoir area of the micro-structured oil reservoir includes: a first determination module configured to determine the depth of the oil-water interface of the micro-structured oil reservoir based on logging data; a second determination module configured to determine at least one oil well among the multiple wells based on the depth of the oil-water interface, and the bottom interface depth of the micro-structured oil reservoir in each well of the at least one oil well is greater than the depth of the oil-water interface; a third determination module configured to determine the top interface seismic reflection time and the bottom interface seismic reflection time of at least one well among the at least one oil well based on the seismic data and logging data of at least one well among the at least one oil well; A fourth determination module, configured to determine a top-interface seismic time slice and a bottom-interface seismic time slice of the at least one well based on the seismic data of the at least one well, the top-interface seismic reflection time, and the bottom-interface seismic reflection time, where the top-interface seismic time slice of the at least one well is used to reflect the seismic imaging of the microstructural oil reservoir at the top-interface seismic reflection time, and the bottom-interface seismic time slice of the at least one well is used to reflect the seismic imaging of the microstructural oil reservoir at the bottom-interface seismic reflection time; A fifth determination module, configured to determine a top-interface structure isopach map of the microstructural oil reservoir based on the top-interface seismic time slice and the bottom-interface seismic time slice; A sixth determination module, configured to determine a reservoir area of the microstructural oil reservoir based on the top-interface structure isopach map and the oil-water interface depth; A seventh determination module, configured to determine an average thickness of the microstructural oil reservoir based on the logging data of each well in the at least one oil well; determine a reservoir area of the microstructural oil reservoir based on the reservoir area of the microstructural oil reservoir; obtain a single-reservoir coefficient of the microstructural oil reservoir based on the logging data; and determine the reserves of the microstructural oil reservoir based on the average thickness, the reservoir area, and the single-reservoir coefficient.

9. The microstructural oil reservoir area determination device according to claim 8, wherein, the third determination module is configured to: determine a time-depth relationship map of the at least one well based on the seismic data and logging data of at least one well in the at least one oil well, where the time-depth relationship map includes logging data in the depth domain, a seismic record synthesized from the logging data, and an original seismic record in the time domain; read the top-interface seismic reflection time and the bottom-interface seismic reflection time of the at least one well from the time-depth relationship map.

Images