A method, system, device and medium for obtaining formation water resistivity eliminating residual hydrocarbon effect

Abstract

The application discloses a method, system and device for obtaining formation water resistivity by eliminating the influence of residual hydrocarbon and a medium, and comprises the following steps: based on the difference among acoustic travel time curves, density curves and neutron logging principles, the acoustic travel time curves and the density curves are inversely scaled to obtain a large-pore index SI; the compensated neutron and the density curves are inversely scaled to obtain a large-pore index SI2 affected by residual hydrocarbon, and the difference H between the two is proportional to the content of residual hydrocarbon in the reservoir; the calibration coefficient K under different formation water resistivities can be obtained by scaling a plurality of oil testing water layers; the conventional resistivity-porosity chart is corrected by using the calibration coefficient, and the bottom water layer method is applied to the corrected chart to obtain the formation water resistivity. The application overcomes the problem that the conventional chart calculates the formation water resistivity value to be large due to the high resistivity of the water layer, and realizes accurate calculation of the formation water resistivity.

Description

Technical Field

[0001] The present invention belongs to the technical field of well logging reservoir evaluation, and relates to a formation water resistivity acquisition method, system, device and medium for eliminating the influence of residual hydrocarbons. Background Art

[0002] Formation water resistivity is a key parameter for determining water saturation in well logging interpretation, and its accuracy directly impacts the quantitative interpretation of hydrocarbons. Currently, there are three main methods for determining formation water resistivity: chemical analysis, spontaneous potential, and the formation resistivity-porosity crossplot method. Chemical analysis, based on formation water samples, is the most direct and accurate method. However, due to limited sample quantities and representativeness issues, it does not meet practical interpretation requirements. The other two methods, which rely on inverse calculations from well logging data, provide consistent results and are widely applicable, but their accuracy varies. According to research by Li Xia et al., the resistivity-porosity crossplot method yields results closest to formation water resistivity determined by laboratory water analysis. This method, also known as the bottom water layer method, projects the resistivity and porosity readings of pure water layers within the interpreted interval onto a series of resistivity-porosity plots corresponding to the formation water resistivity. The formation water resistivity corresponding to the bottom of these points is the formation water resistivity for that interval. Current methods for determining formation water resistivity are not well suited for reservoirs with complex oil-water relationships and the presence of organic matter complexes. The calculated formation water resistivity is often quite different from that obtained from water analysis. Summary of the Invention

[0003] The purpose of the present invention is to solve the problems that the existing methods for obtaining formation water resistivity are not applicable to reservoirs with complex oil-water relationships and the presence of organic matter complexes; the calculated formation water resistivity is often significantly different from the formation water resistivity obtained by water analysis, and to provide a method, system, device and medium for obtaining formation water resistivity that eliminates the influence of residual hydrocarbons.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A method for obtaining formation water resistivity while eliminating the influence of residual hydrocarbons, comprising:

[0006] Based on the acoustic transit time curve and density curve measured by well logging, the macropore index SI is obtained;

[0007] Based on the compensated neutron curve and density curve measured by well logging, the macropore index SI2 affected by residual hydrocarbons is obtained;

[0008] Based on the macropore index SI and the macropore index SI2 affected by residual hydrocarbons, the heavy hydrocarbon index H is obtained;

[0009] Combined with regional oil test data, the resistivity R is obtained through multiple water layer scales and heavy hydrocarbon index H.0校 ; The pure water layer resistivity R0 calculated based on Archie's formula and regional rock electrical parameters; R 0校 Compare with R0 to obtain the correction coefficient K;

[0010] Through the correction coefficient chart, based on the heavy hydrocarbon index H of the water layer in the formation water resistivity interval to be determined, a series of correction coefficients K under formation water resistivity are obtained, and the conventional resistivity-porosity chart is corrected to obtain the corrected chart;

[0011] The water layer of the well section where the formation water resistivity is to be determined is projected, and the formation water resistivity of the well section is obtained by the bottom water layer method.

[0012] A further improvement of the present invention is:

[0013] Furthermore, based on the acoustic transit time curve and density curve measured by well logging, the macropore index SI is obtained, specifically:

[0014]

[0015] Wherein, Δt is the acoustic time difference value measured by well logging; den is the density value measured by well logging; a is the minimum value of the acoustic scale, b is the maximum value of the acoustic scale, c is the minimum value of the density scale, and d is the maximum value of the density scale.

[0016] Furthermore, based on the compensated neutron curve and density curve measured by well logging, the macropore index SI2 affected by residual hydrocarbons is obtained, specifically:

[0017]

[0018] Where den and cnl are the density and compensated neutron values ​​measured by well logging, respectively; SI2 is the difference between the neutron and density curves; e is the minimum value of the compensated neutron scale; and f is the maximum value of the compensated neutron scale.

[0019] At the same time, the density den measured by logging is

[0020]

[0021] Among them, den f is the fluid density value; den ma is the skeleton density value; is the porosity.

[0022] Furthermore, based on the macropore index SI and the macropore index SI2 affected by residual hydrocarbons, the heavy hydrocarbon index H is obtained, specifically:

[0023] H=SI2-SI (4)

[0024] Further, combined with regional test oil data, through multiple water layer scales and heavy hydrocarbon index H, the resistivity R 0校 , specifically:

[0025] R 0校 = 10 A×H+B (5)

[0026] Wherein, A and B are constants.

[0027] Further, based on the Arpich formula and the pure water layer resistivity R0 calculated by the regional rock and electricity parameters; R 0校 and R0 are compared to obtain the correction coefficient K, specifically:

[0028]

[0029]

[0030] Wherein, Rw is the formation water resistivity obtained by water analysis of the test oil layer; a', m are rock and electricity parameters, which are constants in the block.

[0031] A system for obtaining formation water resistivity eliminating the influence of residual hydrocarbon, comprising:

[0032] The first acquisition module obtains the large pore index SI based on the acoustic travel time curve and the density curve measured by logging;

[0033] The second acquisition module obtains the large pore index SI2 affected by residual hydrocarbon based on the compensated neutron curve and the density curve measured by logging;

[0034] The heavy hydrocarbon index acquisition module obtains the heavy hydrocarbon index H based on the large pore index SI and the large pore index SI2 affected by residual hydrocarbon;

[0035] The comparison module, combined with regional test oil data, obtains the resistivity R 0校 through multiple water layer scales and heavy hydrocarbon index H; based on the Arpich formula and the pure water layer resistivity R0 calculated by the regional rock and electricity parameters; R 0校 and R0 are compared to obtain the correction coefficient K;

[0036] The correction module obtains a series of correction coefficients K under a series of formation water resistivities based on the heavy hydrocarbon index H of the water layer of the formation water resistivity layer section to be obtained through the correction coefficient chart, and corrects the conventional resistivity-porosity chart to obtain the corrected chart;

[0037] The formation water resistivity acquisition module projects the water layer of the well section of the formation water resistivity to be obtained, and obtains the formation water resistivity of the well section through the bottom water layer method.

[0038] A terminal device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above method when executing the computer program.

[0039] A computer-readable storage medium stores a computer program, wherein the computer program implements the steps of the above method when executed by a processor.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] Based on the differences between acoustic transit time curves, density curves, and neutron logging principles, the present invention reverse-calibrates the acoustic transit time curves and density curves to obtain the macropore index (SI). The compensated neutron and density curves are reverse-calibrated to obtain the macropore index (SI2) affected by residual hydrocarbons. The difference (H) between the two is proportional to the residual hydrocarbon content in the reservoir. Calibration is performed on multiple test water layers to obtain a correction factor (K) for different formation water resistivities. The correction factor is used to calibrate a conventional resistivity-porosity chart, and the bottom water layer method is applied to the corrected chart to obtain formation water resistivity. This present invention overcomes the problem of inflated formation water resistivity values ​​calculated using conventional charts due to the high resistivity of such water layers, achieving accurate calculation of formation water resistivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0043] Figure 1 A schematic flow chart of a method for obtaining formation water resistivity by eliminating the influence of residual hydrocarbons according to the present invention;

[0044] Figure 2 This is a schematic structural diagram of the formation water resistivity acquisition system for eliminating the influence of residual hydrocarbons according to the present invention;

[0045] Figure 3 Another schematic flow chart of the method for obtaining formation water resistivity by eliminating the influence of residual hydrocarbons according to the present invention;

[0046] Figure 4 It is a schematic diagram of the correction coefficient plate of the present invention;

[0047] Figure 5 Schematic diagram of the corrected resistivity-porosity chart (H=0.14) of the present invention;

[0048] Figure 6 This is a schematic diagram of an example of obtaining formation water resistivity according to the present invention. DETAILED DESCRIPTION

[0049] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0050] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0051] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0052] In the description of the embodiments of the present invention, it should be noted that if the terms "upper," "lower," "horizontal," "inner," etc. appear, the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the inventive product is typically placed when in use. These terms are merely for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first," "second," etc. are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0053] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0054] In the description of the embodiments of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0055] The present invention is described in further detail below with reference to the accompanying drawings:

[0056] See also Figure 1 The present invention discloses a method for obtaining formation water resistivity by eliminating the influence of residual hydrocarbons, comprising:

[0057] S101, obtaining a macropore index SI based on the acoustic time difference curve and density curve measured by well logging.

[0058] The acoustic time difference mainly propagates between contacting particles, reflecting the interconnected intergranular pores in the rock, i.e., macropores. The density curve measures the volume density of the rock, reflecting the total porosity of the rock. The smaller the density, the larger the total pores, and the larger the acoustic wave, the more macropores. Both the acoustic time difference and density curves use a linear scale. The acoustic time difference curve and the density curve are overlapped. The two basically coincide in reservoir sections with pure lithology and good physical properties, and there will be an envelope in other well sections, so as to determine the appropriate left and right scale values ​​for the study area. The overlapping envelope area of ​​the two can reflect the macropores in the reservoir and the proportion they occupy, which is called the macropore index SI. The specific formula is:

[0059]

[0060] Wherein, Δt is the acoustic time difference value measured by well logging; den is the density value measured by well logging; a is the minimum value of the acoustic scale, b is the maximum value of the acoustic scale, c is the minimum value of the density scale, and d is the maximum value of the density scale.

[0061] S102, obtaining a macropore index SI2 affected by residual hydrocarbons based on the compensated neutron curve and density curve measured by well logging.

[0062] Compensated neutron logging measures the hydrogen content in the reservoir and has a good indication effect on mud or micropores. Mudstone has high neutron and high density characteristics, while reservoirs have low neutron and low density characteristics. Reverse scaling of the two has a good mud indication and stratification effect. Due to its advantages in resolution and indication of physical properties, its stratification effect is even better than the commonly used natural potential and natural gamma curves. The compensated neutron and density curves both use linear scales, and the two are reversely overlapped so that their stratification boundaries are the same as natural gamma, so as to determine the left and right scale values ​​suitable for the study area. The larger the envelope area of ​​the two, the more macropores (total pores-micropores) there are in the reservoir. The residual hydrocarbons existing in the macropores after the reservoir is destroyed have the characteristics of heavy carbon and light hydrocarbons, which will cause the compensated neutron logging value of the reservoir to decrease. That is, the influence of residual hydrocarbons will cause the neutron-density envelope area to become larger, which is called the macropore index SI2 affected by residual hydrocarbons. The specific formula is

[0063]

[0064] Where den and cnl are the density and compensated neutron values ​​measured by well logging, respectively; SI2 is the difference between the neutron and density curves; e is the minimum value of the compensated neutron scale; and f is the maximum value of the compensated neutron scale.

[0065] At the same time, the density den measured by logging is

[0066]

[0067] Among them, den f is the fluid density value; den ma is the skeleton density value; is the porosity.

[0068] S103, obtaining a heavy hydrocarbon index H based on the macropore index SI and the macropore index SI2 affected by residual hydrocarbons.

[0069] Subtract SI2 from SI, and the difference is the effect of residual hydrocarbons in the macropores on the logging value. This difference is called the heavy hydrocarbon index H, which is proportional to the residual oil content in the reservoir. The specific formula is:

[0070] H=SI2-SI (4)

[0071] S104, combined with regional oil test data, through multiple water layer scales and heavy hydrocarbon index H, obtain the resistivity R 0校 ; The pure water layer resistivity R0 calculated based on Archie's formula and regional rock electrical parameters; R 0校 Compare with R0 to obtain the correction coefficient K.

[0072]

[0073]

[0074] Wherein, Rw is the formation water resistivity obtained by water analysis of the oil testing horizon; a', m are litho-electric parameters, which are constants in the block.

[0075] S105, through the correction coefficient chart, based on the heavy hydrocarbon index H of the water layer of the formation water resistivity layer section to be solved, a series of correction coefficients K under a series of formation water resistivities are obtained, and the conventional resistivity-porosity chart is corrected to obtain the corrected chart.

[0076] S106, the water layer of the well section of the formation water resistivity to be solved is projected, and the formation water resistivity of the well section is obtained by the bottom water layer method.

[0077] Referring to Figure 2 , the application discloses a formation water resistivity acquisition system for eliminating the influence of residual hydrocarbon, comprising:

[0078] The first acquisition module obtains a large pore index SI based on the acoustic travel time curve and the density curve measured by logging;

[0079] The second acquisition module obtains a large pore index SI2 affected by residual hydrocarbon based on the compensated neutron curve and the density curve measured by logging;

[0080] The heavy hydrocarbon index acquisition module obtains a heavy hydrocarbon index H based on the large pore index SI and the large pore index SI2 affected by residual hydrocarbon;

[0081] The comparison module combines regional oil testing data, and obtains resistivity R 0校 of the water layer through the heavy hydrocarbon index H and the multiple water layer scales; the pure water layer resistivity R0 calculated based on the Archie formula and regional litho-electric parameters; and the resistivity R 0校 is compared with the resistivity R0 to obtain a correction coefficient K;

[0082] The correction module obtains a series of correction coefficients K under a series of formation water resistivities based on the heavy hydrocarbon index H of the water layer of the formation water resistivity layer section to be solved through the correction coefficient chart, and corrects the conventional resistivity-porosity chart to obtain a corrected chart.

[0083] The formation water resistivity acquisition module projects the water layer of the well section of the formation water resistivity to be solved, and obtains the formation water resistivity of the well section by the bottom water layer method.

[0084] Embodiment:

[0085] Referring to Figure 3 , the application discloses a formation water resistivity acquisition method for eliminating the influence of residual hydrocarbon, comprising the following steps:

[0086] S100, overlapping the acoustic time difference curve and the density curve, and using the envelope area of ​​the overlapped curve to obtain the macropore index SI;

[0087] Specifically, the acoustic transit time curve and the density curve are overlapped. The two curves basically coincide in reservoir sections with pure lithology and good physical properties, and there is an envelope in other well sections. This is used to determine the appropriate left and right scale values ​​for the study area. The distance between the two curves is the SI, called the macropore index, and the formula is:

[0088]

[0089] Where Δt is the acoustic time difference value measured by well logging, in units of us / m; den is the density value measured by well logging, in units of g / cm 3 ;

[0090] S200, the compensated neutron and density curves are reversely scaled and superimposed to obtain the macropore index SI2 affected by residual heavy hydrocarbons;

[0091] Specifically, the compensated neutron and density curves are both scaled linearly, and the two are reversely overlapped so that their stratification boundaries are the same as those of the natural gamma ray. This is used to determine the appropriate left and right scale values ​​for the study area. The envelope area of ​​the two is the macropore index SI2 affected by residual heavy hydrocarbons, and the formula is:

[0092]

[0093] Where, den and cnl are the density and compensated neutron value measured by well logging, respectively, and the units are g / cm 3 , %; SI2 is the difference between neutron and density curves, no unit;

[0094] S300, subtract SI2 from SI to obtain the heavy hydrocarbon index H, the specific formula is:

[0095] H=SI2-SI

[0096] S400, combined with regional oil test data, obtains the resistivity correction value R through multiple water layer calibrations 0校 ; Use density to obtain total porosity through volume model; Use Archie formula and regional rock electrical parameters to obtain pure water layer resistivity R0; R 0校 Compare with R0 to get the correction coefficient K plate, see Figure 4 :

[0097] Specifically, the resistivity R 0校 The calculation formula is as follows:

[0098] R 0校 =10 2.7×H+1.0664

[0099]

[0100]

[0101]

[0102] Where, Rw is the formation water resistivity obtained by water analysis at the test oil layer, in Ω.m; H is the residual index obtained in S300, without unit; den, den f 、den ma They are respectively the density, fluid density and skeleton density measured by well logging, in g / cm 3 ; is the porosity, a decimal.

[0103] S600: Correct the conventional resistivity-porosity chart using the correction coefficient to obtain a corrected resistivity-porosity chart, and use the bottom water layer method to obtain the formation water resistivity of the high resistivity water layer;

[0104] Specifically, through the correction coefficient chart, according to the heavy hydrocarbon index H of the water layer in the formation water resistivity interval to be obtained, a series of R w The correction coefficient K under the condition of , the conventional resistivity-porosity chart (solid line) is corrected to obtain the corrected chart (dashed line), see Figure 5 The water layer of the well section where the formation water resistivity is to be determined is projected onto this plate, and the formation water resistivity of this well section is obtained using the bottom water layer method.

[0105] Figure 6 This is an example of water layer interpretation using this method. The first channel is the resistivity curve, the second channel is the three-porosity curve, the third channel is the depth channel, the fourth channel is the mud logging display channel, the fifth channel is the interpretation conclusion channel, the sixth channel is the lithology logging channel, the seventh channel is the porosity channel, the eighth channel is the permeability channel, the ninth channel is the macropore index channel, the tenth channel is the residual index channel, and the eleventh channel is the logging interpretation lithology profile channel. From the logging curve, the density of layer 51 is 2.53 g / cm 3 , the acoustic time difference is 218us / m, the porosity is 10.7%, the resistivity is 67.7Ω.m, and it is a high resistivity water layer. The heavy hydrocarbon index H calculated for this layer is 0.14. Figure 4 Get R on the correction coefficient chart w A series of correction coefficients ranging from 0.04Ω.m to 0.5Ω.m are shown in Table 1. The conventional porosity-resistivity chart is corrected to obtain the corrected chart. Figure 6 The porosity and resistivity values ​​of the 51st layer are projected onto this plate, see Figure 5 The bottom value of this layer segment corresponds to R on the original map. wIt is about 0.42Ω.m, which corresponds to R on the calibration chart. w The resistivity of the formation water R is calculated based on the produced water analysis data (Table 2). w It is 0.32Ω.m, which shows that the corrected chart can get more accurate calculation results. By comparing the corrected chart with the original chart, it can be seen that when R w When the correction amount is small, the correction amount of both is large. w Increasing the correction amount makes it smaller, which is consistent with geological laws.

[0106] Table 1

[0107] <![CDATA[R w / Ω.m]]> 0.04 0.06 0.08 0.1 0.12 0.15 0.2 0.3 0.4 0.5 K 2.3 2.25 2.15 2.1 2 1.9 1.82 1.5 1.24 1.04

[0108] Table 2

[0109]

[0110] The water layer formed after the ancient oil reservoir was destroyed is due to heavy components such as asphaltene adhering to the surface of rock particles, combining with clay films to form organic matter complexes, blocking the rock conductive network and forming high-resistivity water layers. The conventional porosity-resistivity chart is not accurate for calculating the formation water resistivity. The present invention realizes the quantitative characterization of residual hydrocarbons in the reservoir by using the differences in the principles of different logging curves. On this basis, the resistivity is corrected to obtain the resistivity-porosity cross-plot corrected for residual heavy hydrocarbons. On this basis, the bottom water layer method is adopted to improve the accuracy of formation water resistivity calculation.

[0111] The quantitative characterization technology in the present invention can not only be applied to the calculation of formation water resistivity, but also can be used to identify the fluid properties of complex reservoirs, on this basis, reservoir productivity classification and other tasks can be carried out.

[0112] An embodiment of the present invention provides a terminal device. The terminal device of this embodiment includes: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of each of the aforementioned method embodiments are implemented. Alternatively, when the processor executes the computer program, the functions of each module / unit in each of the aforementioned device embodiments are implemented.

[0113] The computer program may be divided into one or more modules / units, which are stored in the memory and executed by the processor to accomplish the present invention.

[0114] The terminal device may be a computing device such as a desktop computer, a notebook computer, a PDA, a cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0115] The processor can be a central processing unit (CPU), and can also be other general-purpose processors, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, etc.

[0116] The memory can be used to store the computer program and / or modules, and the processor realizes various functions of the terminal device by running or executing the computer program and / or modules stored in the memory, and calling data stored in the memory.

[0117] The modules / units integrated in the terminal device, if realized in the form of software function units and sold or used as independent products, can be stored in a computer readable storage medium. Based on such understanding, all or part of the processes in the above-mentioned embodiment methods can also be completed by a computer program instructing related hardware, and the computer program can be stored in a computer readable storage medium. The computer program can realize the steps of the above-mentioned various method embodiments when executed by a processor. The computer program includes computer program code, which can be in the form of source code, object code, executable file or some intermediate form. The computer readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal and software distribution medium, etc. It should be noted that the computer readable medium can include or exclude contents according to the requirements of legislation and patent practice in the jurisdiction, for example, in some jurisdictions, according to legislation and patent practice, the computer readable medium does not include electrical carrier signals and telecommunication signals.

[0118] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for obtaining formation water resistivity by eliminating the influence of residual hydrocarbons, characterized in that: include: Based on the acoustic transit time curve and density curve measured by well logging, the macropore index SI is obtained; Based on the compensated neutron curve and density curve measured by well logging, the macropore index SI2 affected by residual hydrocarbons is obtained; Based on the macropore index SI and the macropore index SI2 affected by residual hydrocarbons, the heavy hydrocarbon index H is obtained; Combined with regional oil test data, the resistivity R is obtained through multiple water layer scales and heavy hydrocarbon index H. 0校 ; The pure water layer resistivity R0 is calculated based on Archie's formula and regional rock electrical parameters; R 0校 Compare with R0 to obtain the correction coefficient K; Through the correction coefficient chart, based on the heavy hydrocarbon index H of the water layer in the formation water resistivity interval to be determined, a series of correction coefficients K under formation water resistivity are obtained, and the conventional resistivity-porosity chart is corrected to obtain the corrected chart; Project the water layer of the well section where the formation water resistivity is to be determined, and obtain the formation water resistivity of the well section by the bottom water layer method; The macropore index SI is obtained based on the acoustic time difference curve and density curve measured by well logging, specifically: in, is the acoustic time difference value measured by well logging; den is the density value measured by well logging; a is the minimum value of the acoustic scale, b is the maximum value of the acoustic scale, c is the minimum value of the density scale, and d is the maximum value of the density scale; The macropore index SI2 affected by residual hydrocarbons is obtained by compensating the neutron curve and density curve based on the well logging measurement, specifically: Where den and cnl are the density and compensated neutron values ​​measured by well logging, respectively; SI2 is the difference between the neutron and density curves, e is the minimum value of the compensated neutron scale, and f is the maximum value of the compensated neutron scale; The heavy hydrocarbon index H is obtained based on the macropore index SI and the macropore index SI2 affected by residual hydrocarbons, specifically: (4); The resistivity R is obtained by combining the regional oil test data with multiple water layer scales and heavy hydrocarbon index H. 0校 , specifically: Where A and B are both constants.

2. The method for obtaining formation water resistivity by eliminating the influence of residual hydrocarbons according to claim 1, characterized in that: At the same time, the density den measured by logging is in, is the fluid density value; is the skeleton density value; is the porosity.

3. The method for obtaining formation water resistivity by eliminating the influence of residual hydrocarbons according to claim 1, characterized in that: The pure water layer resistivity R0 calculated based on Archie's formula and regional rock electrical parameters; R 0校 Comparing with R0, we get the correction coefficient K, which is: Wherein, Rw is the formation water resistivity obtained by water analysis at the test oil layer; a' and m are rock electrical parameters, which are constant within the block.

4. A formation water resistivity acquisition system for eliminating the influence of residual hydrocarbons, characterized in that: include: A first acquisition module, wherein the first acquisition module obtains a macropore index SI based on an acoustic wave time difference curve and a density curve measured by well logging; a second acquisition module, wherein the second acquisition module obtains a macropore index SI2 affected by residual hydrocarbons based on a compensated neutron curve and a density curve measured by well logging; A heavy hydrocarbon index acquisition module, wherein the heavy hydrocarbon index acquisition module obtains a heavy hydrocarbon index H based on the macropore index SI and the macropore index SI2 affected by residual hydrocarbons; Comparison module, which combines regional oil test data, obtains resistivity R through multiple water layer scales and heavy hydrocarbon index H 0校 ; The pure water layer resistivity R0 is calculated based on Archie's formula and regional rock electrical parameters; R 0校 Compare with R0 to obtain the correction coefficient K; A correction module, which uses a correction coefficient chart to obtain a series of correction coefficients K under formation water resistivity based on the heavy hydrocarbon index H of the water layer in the formation water resistivity interval to be determined, and corrects the conventional resistivity-porosity chart to obtain a corrected chart; a formation water resistivity acquisition module, which projects the water layer of the well section for which the formation water resistivity is to be obtained, and obtains the formation water resistivity of the well section by a bottom water layer method; The macropore index SI is obtained based on the acoustic time difference curve and density curve measured by well logging, specifically: in, is the acoustic time difference value measured by well logging; den is the density value measured by well logging; a is the minimum value of the acoustic scale, b is the maximum value of the acoustic scale, c is the minimum value of the density scale, and d is the maximum value of the density scale; The macropore index SI2 affected by residual hydrocarbons is obtained by compensating the neutron curve and density curve based on the well logging measurement, specifically: Where den and cnl are the density and compensated neutron values ​​measured by well logging, respectively; SI2 is the difference between the neutron and density curves, e is the minimum value of the compensated neutron scale, and f is the maximum value of the compensated neutron scale; The heavy hydrocarbon index H is obtained based on the macropore index SI and the macropore index SI2 affected by residual hydrocarbons, specifically: (4); The resistivity R is obtained by combining the regional oil test data with multiple water layer scales and heavy hydrocarbon index H. 0校 , specifically: Where A and B are both constants.

5. A terminal device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 3 are implemented.

6. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 3 are implemented.

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