Method, device, medium and equipment for calibrating porosity of buried hill fractured reservoir logging

Abstract

The present invention relates to a method, device, medium and equipment for calibrating the logging porosity of a buried-hill fractured reservoir. The method comprises: conducting physical property analysis based on a sample of a buried-hill fractured reservoir in an oil and gas field to obtain porosity and permeability; constructing a cross-plot of the porosity and permeability of the buried-hill fractured reservoir in the oil and gas field based on the porosity and permeability, and determining the limit values ​​of the permeabilities of the full-diameter core samples and the plug core samples according to the distribution ranges of the permeabilities of the full-diameter core samples and the plug core samples in the cross-plot; calculating the fracture porosity, permeability and logging porosity of the buried-hill fractured reservoir in the oil and gas field based on the logging data of the buried-hill fractured reservoir in the oil and gas field; and comparing the calculated permeability of the buried-hill fractured reservoir in the oil and gas field with the limit values ​​of the permeabilities of the full-diameter core samples and the plug core samples to determine the development of the buried-hill fractured reservoir in the oil and gas field.

Description

Technical Field

[0001] The invention relates to a method, device, medium and equipment for calibrating the well logging porosity of a buried hill fractured reservoir, and belongs to the technical field of marine oil and gas field exploitation. Background Art

[0002] Porosity, hydrocarbon saturation, effective thickness, and hydrocarbon-bearing area are the four key parameters for calculating proven geological reserves. Porosity is generally obtained by calibrating the porosity calculated from well logging using core analysis porosity. Currently, relatively little analytical data is available from drill cores and full-diameter cores (hereinafter referred to as "full-diameter cores") for offshore buried-hill fractured reservoirs. However, more analytical data is available from plug cores or wall cores (hereinafter referred to as "plug cores") . Generally, porosity from full-diameter core analysis includes both matrix porosity and fracture porosity, representing total porosity. Permeability from full-diameter core analysis includes both matrix permeability and fracture permeability, representing total permeability. Due to the limitations of plug size, porosity from plug core analysis represents only matrix porosity and does not include fracture porosity. Therefore, using the porosity of plunger core analysis to calibrate the porosity calculated by well logging will result in a smaller porosity calculated by well logging, and thus make the calculated proved geological reserves of buried-hill fractured oil and gas reservoirs smaller.

[0003] First, the effectiveness of fractures is determined by their contribution to permeability. If effective fractures are present, the porosity calculated from well logging for buried-hill fractured reservoirs should be equal to the sum of matrix porosity and fracture porosity. When full-diameter core analysis data are available, the porosity calculated from well logging should be calibrated using the porosity from full-diameter core analysis. If full-diameter core analysis data are unavailable, the porosity calculated from well logging should be calibrated using the sum of the porosity from plug core analysis and fracture porosity. Conversely, if ineffective or absent fractures are present, the porosity calculated from well logging should be calibrated using the porosity from plug core analysis. Therefore, a well logging porosity calibration method for buried-hill fractured oil and gas reservoirs has been developed, laying an important foundation for accurately calculating the proven reserves in deep and ultra-deep buried-hill fractured oil and gas fields. Summary of the Invention

[0004] In response to the above technical problems, the present invention provides a method, device, medium and equipment for calibrating the porosity of buried hill fractured reservoirs by well logging. The method can accurately calculate the porosity of deep / ultra-deep buried hill fractured reservoirs and objectively estimate the proven geological reserves of buried hill fractured oil and gas fields.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for calibrating the porosity of a buried-hill fractured reservoir by logging, comprising:

[0007] Physical property analysis is conducted on full-diameter core samples and plug core samples taken at a certain depth from fractured reservoirs in buried hills of oil and gas fields to obtain the porosity and permeability of the full-diameter core samples and plug core samples.

[0008] Based on the porosity and permeability of full-diameter core samples and plug core samples, a crossplot of the porosity and permeability of full-diameter core samples and plug core samples in the buried-hill fractured reservoir of the oil and gas field was constructed. Based on the distribution range of the permeability of the full-diameter core samples and the permeability of the plug core samples in the crossplot, the boundary values ​​of the permeability of the full-diameter core samples and the permeability of the plug core samples were determined;

[0009] Based on the well logging data of the fractured reservoirs in the buried hills of oil and gas fields, the fracture porosity of the fractured reservoirs in the buried hills of oil and gas fields is calculated;

[0010] Based on the well logging data of the fractured reservoir in the buried hill of the oil and gas field, the permeability of the fractured reservoir in the buried hill of the oil and gas field is calculated;

[0011] Based on the logging data of the fractured reservoir in the buried hill of the oil and gas field, the logging porosity of the fractured reservoir in the buried hill of the oil and gas field is calculated;

[0012] By comparing the calculated permeability of the fractured reservoir in the buried hill of the oil and gas field with the limit values ​​of the permeability of the full-diameter core sample and the permeability of the plunger core sample, the development of the fractured reservoir in the buried hill of the oil and gas field and the error size between the logging porosity and the fracture porosity and the porosity of the plunger core sample can be judged.

[0013] In the method for calibrating the porosity of buried-hill fractured reservoir logging, preferably, the logging data include natural gamma, natural potential, deep resistivity, medium resistivity, shallow resistivity, volume density, neutron porosity, compressional wave time difference, shear wave time difference, Stoneley wave time difference and electrical imaging.

[0014] The method for calibrating the logging porosity of the buried-hill fractured reservoir is preferably based on the logging data of the buried-hill fractured reservoir of the oil and gas field to calculate the fracture porosity of the buried-hill fractured reservoir of the oil and gas field. The calculation formula of the fracture porosity is as follows:

[0015]

[0016] Where: φ f is the fracture porosity; m f is the fracture porosity index; R m is the mud resistivity; R s is the shallow lateral resistivity; K f is the crack distortion coefficient; Rd is the deep lateral resistivity.

[0017] The method for calibrating the porosity of a buried-hill fractured reservoir by well logging is preferably based on the well logging data of the buried-hill fractured reservoir of the oil and gas field to calculate the permeability of the buried-hill fractured reservoir of the oil and gas field. The calculation formula of the permeability is as follows:

[0018]

[0019] Where: K t is the well logging permeability; is the frequency shift of Stoneley waves; is the time lag of the Stoneley wave.

[0020] The method for calibrating the logging porosity of the buried-hill fractured reservoir is preferably based on the logging data of the buried-hill fractured reservoir of the oil and gas field to calculate the logging porosity of the buried-hill fractured reservoir of the oil and gas field. The calculation formula of the logging porosity is as follows:

[0021]

[0022] Where: φ t is the well logging porosity; GR is natural gamma; R t is the deep resistivity; R xo is the resistivity of the flushing zone; DEN is the bulk density; NPHI is the neutron porosity; DT is the longitudinal wave time difference.

[0023] The method for calibrating the logging porosity of a buried-hill fractured reservoir preferably compares the calculated permeability of the buried-hill fractured reservoir of the oil and gas field with the limit values ​​of the permeability of the full-diameter core sample and the permeability of the plunger core sample to judge the development of the buried-hill fractured reservoir of the oil and gas field and the error between the logging porosity and the fracture porosity and the porosity of the plunger core sample, as follows:

[0024] When the calculated permeability of the buried-hill fractured reservoir in an oil and gas field is greater than or equal to the limit value of the permeability of the full-diameter core sample and the permeability of the plunger core sample, it indicates that effective fractures are developed in the buried-hill fractured reservoir; otherwise, it indicates that no fractures are developed in the buried-hill fractured reservoir or ineffective fractures are developed.

[0025] The method for calibrating the logging porosity of a buried-hill fractured reservoir is preferably such that when the calculated permeability of the buried-hill fractured reservoir of an oil and gas field is greater than or equal to the limit value of the permeability of a full-diameter core sample and the permeability of a plunger core sample, the error between the logging porosity and the sum of the fracture porosity and the porosity of the plunger core sample is minimized.

[0026] A second aspect of the present invention provides a porosity calibration device for well logging of a buried-hill fractured reservoir, comprising:

[0027] The first processing unit is used to perform physical property analysis based on full-diameter core samples and plunger core samples at a certain depth of the buried hill fracture reservoir of the oil and gas field to obtain the porosity and permeability of the full-diameter core samples and plunger core samples;

[0028] The second processing unit is used to construct a cross-plot of the porosity and permeability of the full-diameter core sample and the plug core sample of the buried-hill fractured reservoir of the oil and gas field based on the porosity and permeability of the full-diameter core sample and the plug core sample, and determine the limit values ​​of the permeability of the full-diameter core sample and the permeability of the plug core sample according to the distribution range of the permeability of the full-diameter core sample and the permeability of the plug core sample in the cross-plot;

[0029] The third processing unit is configured to calculate the fracture porosity of the buried hill fracture reservoir of the oil and gas field based on the well logging data of the buried hill fracture reservoir of the oil and gas field;

[0030] The fourth processing unit is configured to calculate the permeability of the buried hill fractured reservoir of the oil and gas field based on the well logging data of the buried hill fractured reservoir of the oil and gas field;

[0031] A fifth processing unit is configured to calculate the logging porosity of the buried-hill fractured reservoir in the oil and gas field based on the logging data of the buried-hill fractured reservoir in the oil and gas field;

[0032] The sixth processing unit is used to compare the calculated permeability of the fractured reservoir in the buried hill of the oil and gas field with the limit values ​​of the permeability of the full-diameter core sample and the permeability of the plunger core sample, to determine the development of the fractured reservoir in the buried hill of the oil and gas field and the error between the logging porosity and the fracture porosity and the porosity of the plunger core sample.

[0033] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the computer program implements the steps of any one of the above-mentioned methods for calibrating the porosity of buried-hill fractured reservoir logging.

[0034] A fourth aspect of the present invention provides a computer 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 any one of the above-mentioned methods for calibrating the porosity of buried-hill fractured reservoir logging are implemented.

[0035] The present invention has the following advantages due to the adoption of the above technical solution:

[0036] 1. The method of the present invention avoids the need for extensive coring and full-diameter core analysis, effectively saving costs and improving the efficiency of exploration and development of buried-hill fractured oil and gas reservoirs, thereby having strong economic efficiency.

[0037] 2. The method of the present invention provides an effective, simple and practical new method while ensuring accurate calculation of the porosity of deep / ultra-deep buried hill fractured reservoirs. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 yes A Crossplot of the full diameter of the fractured reservoir in the buried hill of the oil field, the porosity of the plunger core analysis, and the permeability of the core analysis;

[0039] Figure 2 yes B Crossplot of the full diameter of the fractured reservoir in the buried hill of the oil field, the porosity of the plunger core analysis, and the permeability of the core analysis;

[0040] Figure 3 yes A oilfield A1 Results of fracture porosity, porosity calculated by well logging, and permeability calculated by well logging in the fractured reservoir intervals with more developed fractures in the buried hill;

[0041] Figure 4 yes B oilfield B1 Results of fracture porosity, porosity calculated by well logging, and permeability calculated by well logging in the fractured reservoir intervals with more developed fractures in the buried hill;

[0042] Figure 5 yes A oilfield A2 Results of fracture porosity, porosity calculated by well logging, and permeability calculated by well logging in the intervals where fractures are not developed in the fractured reservoir of the buried hill;

[0043] Figure 6 yes B oilfield B1 Results of fracture porosity, porosity calculated by well logging, and permeability calculated by well logging in the fractured reservoir section with sparse fractures in the buried hill. DETAILED DESCRIPTION

[0044] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention are described clearly and completely below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by ordinary persons in this field based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0045] Unless otherwise defined, the technical or scientific terms used in the present invention shall have the usual meanings understood by persons of ordinary skill in the field to which the present invention belongs. The words "first", "second", "third", "fourth" and similar terms used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" mean that the elements or objects preceding the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0046] For ease of description, spatially relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figures, such as "inside," "outside," "inner side," "outer side," "lower," "upper," etc. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures.

[0047] The effectiveness of fractures is determined by their contribution to permeability. If effective fractures are present, the porosity calculated from well logging for buried-hill fractured reservoirs should be equal to the sum of matrix porosity and fracture porosity. When full-diameter core analysis data are available, the porosity calculated from well logging should be calibrated using the porosity from full-diameter core analysis. If full-diameter core analysis data are unavailable, the porosity calculated from well logging should be calibrated using the sum of the porosity from plug core analysis and the fracture porosity. Conversely, if ineffective or absent fractures are present, the porosity calculated from well logging should be calibrated using the porosity from plug core analysis. Therefore, a well logging porosity calibration method for buried-hill fractured oil and gas reservoirs has been developed, laying an important foundation for accurately calculating the proven geological reserves of deep and ultra-deep buried-hill fractured oil and gas fields.

[0048] Based on the above technical problems, the present invention provides a well logging porosity calibration method for buried hill fractured reservoirs, which can accurately calculate the porosity of deep / ultra-deep buried hill fractured reservoirs and objectively estimate the proven geological reserves of buried hill fractured oil and gas fields.

[0049] like Figure 1As shown, the method for calibrating the porosity of a buried hill fractured reservoir provided by the present invention includes the following specific steps:

[0050] 1) Based on the full-diameter core samples and plug core samples at a certain depth of the fractured reservoir in a buried hill of a certain oil and gas field, the physical property analysis of the full-diameter core samples and plug core samples was carried out to measure the porosity and permeability of each full-diameter core sample and plug core sample, namely the full-diameter core and plug core analytical porosity and core analytical permeability. The full-diameter core analytical porosity and core analytical permeability represent the total porosity ( φ tc ) and total permeability ( K tc ), plug core analysis porosity and core analysis permeability represent matrix porosity ( φ mc ) and matrix permeability ( K mc ).

[0051] 2) Based on the core analysis porosity and core analysis permeability of the full-diameter core samples and plug core samples at a certain depth of the buried-hill fractured reservoir of a certain oil and gas field in step 1), a cross-plot of the full-diameter core, plug core analysis porosity and core analysis permeability of the buried-hill fractured reservoir of the oil and gas field is constructed. According to the distribution range of the full-diameter core analysis permeability and the plug core analysis permeability in the cross-plot, the limit values ​​of the full-diameter core analysis permeability and the plug core analysis permeability are determined ( D ). The permeability is greater than or equal to the limit value ( D ), indicating the development of effective fractures; the permeability is less than this limit value ( D ), indicating that no effective cracks are developed.

[0052] Figure 1 yes A The cross-plot of porosity and permeability of full-diameter core, plunger core analysis and core analysis of fractured reservoir in buried hill of oilfield is shown in Figure 1. Figure 1 It can be seen that A Limit values ​​of permeability of full-diameter core analysis and plug core analysis in oil fields D =0.1mD.

[0053] Figure 2 yes B The cross-plot of porosity and permeability of full-diameter core, plunger core analysis and core analysis of fractured reservoir in buried hill of oilfield is shown in Figure 1. Figure 2 It can be seen that B Limit values ​​of permeability of full-diameter core analysis and plug core analysis in oil fields D =1.0mD.

[0054] 3) For the buried-hill fractured reservoir of the oil and gas field, the logging instrument can measure a series of logging data (natural gamma, natural potential, deep resistivity, medium resistivity, shallow resistivity, volume density, neutron porosity, compressional wave transit time, shear wave transit time, Stoneley wave transit time, electrical imaging); based on the deep resistivity and shallow resistivity logging data, the fracture porosity of the buried-hill fractured reservoir can be calculated, as shown in formula (1):

[0055] (1)

[0056] Where: φ f is the fracture porosity, %; m f is the fracture porosity index, dimensionless, usually 1.3-1.8; R m is the mud resistivity, Ω·m; R s is the shallow lateral resistivity, Ω·m; K f is the crack distortion coefficient, which is about 1.3 for horizontal cracks and about 1.0 for vertical cracks; R d is the deep lateral resistivity, Ω·m.

[0057] 4) Based on the Stoneley waves of the buried-hill fractured reservoir in a well of the oil and gas field acquired in step 3), the main frequency and arrival time of the Stoneley waves are matched, and the calculation formula of the permeability of the buried-hill fractured reservoir is constructed using the least squares method, as shown in formula (2):

[0058] (2)

[0059] Where: K t is the well logging permeability, mD; is the frequency shift of the Stoneley wave, kHz; is the Stoneley wave lag, ms.

[0060] Minimize the error between the permeability calculated by well logging and the permeability of the full-diameter core analysis in step 2).

[0061] 5) Based on the natural gamma, deep resistivity, shallow resistivity, bulk density, neutron porosity, P-wave time difference and other logging data of the buried-hill fracture reservoir in a well of the oil and gas field collected in step 3), the rock mineral component content and porosity of the buried-hill fracture reservoir can be calculated, that is, the logging porosity, as shown in formula (3):

[0062] (3)

[0063] Where: φt is the logging porosity, %; GR is natural gamma, API; R t is the deep resistivity, Ω·m; R xo is the resistivity of the flushing zone, Ω·m; DEN is the bulk density, g / cm 3 ; NPHI is the neutron porosity, %; DT is the longitudinal wave time difference, μs / ft.

[0064] 6) When the permeability is calculated in step 4) K t Greater than or equal to the limit value of the full-diameter core analysis permeability and the plunger core analysis permeability in step 2) D When , it indicates that the buried-hill fracture reservoir has developed effective fractures; otherwise, it indicates that the buried-hill fracture reservoir has no fractures or has developed ineffective fractures.

[0065] 7) When K t ≥ D When the porosity is calculated in step 5) φ t The porosity should be analyzed with the plunger core in step 1). φ mc and step 3) fracture porosity φ f The error between the sums is minimal.

[0066] The present invention can obtain parameters such as fracture porosity, logging-calculated porosity, logging-calculated permeability, etc. of the buried-hill fracture reservoir through processing and interpretation by logging software such as Geolog, Techlog, and CIFLog.

[0067] Figure 3 yes A oilfield A1 Results of fracture porosity, total porosity calculated by well logging, and total permeability calculated by well logging in the fractured reservoir with more developed fractures in the buried hill:

[0068] Track 1 is the measured depth of the formation;

[0069] The second track is the natural gamma and well diameter, indicating the lithologic characteristics of the formation;

[0070] The third track is the deep and shallow resistivity logging curves, which depict the electrical characteristics of the formation;

[0071] Track 4 is the volume density, neutron porosity and acoustic transit time, reflecting the physical properties of the formation;

[0072] Track 5 is fracture porosity;

[0073] Track 6 is the full-diameter, plug-core analysis porosity;

[0074] Track 7 is the sum of the plug core analysis porosity and the fracture porosity, the plug core analysis porosity;

[0075] Track 8 is the total porosity from core analysis (including the sum of the porosity from full-diameter core analysis, the porosity from plug core analysis, and the porosity from fractures) and the total porosity calculated from well logging;

[0076] Track 9 is the permeability of the full-diameter core analysis and the total permeability calculated by well logging;

[0077] Track 10 shows the contents of quartz, feldspar and mica calculated by well logging.

[0078] From the 9th track, we can see that the permeability of the full-diameter core analysis, that is, the total permeability of the core analysis, is in good agreement with the permeability calculated by Stoneley wave in step 4), that is, the total permeability calculated by well logging, indicating that the total permeability calculated by well logging is highly accurate. From step 2), we can see that A Limit values ​​of permeability of full-diameter core analysis and plug core analysis in oil fields D =0.1mD; while the total permeability calculated by well logging is basically greater than 0.1mD, indicating that Figure 3 shown A oilfield A1 The fractured reservoirs in the buried hill have effective fractures. Therefore, in addition to the porosity analysis of the full-diameter core (with relatively few data points), A oilfield A1 The total porosity of the fractured reservoir in the buried hill is equal to the sum of the porosity of the plunger core analysis (relatively more data points) and the fracture porosity, see Figure 3 Track 7. Track 8 shows the absolute error between the total porosity from core analysis (including the sum of the porosity from full-diameter core analysis, the porosity from plug core analysis, and the porosity from fractures) and the total porosity calculated from well logging, which is 4.76%. The absolute error between the porosity from plug core analysis and the total porosity calculated from well logging is 8.79%.

[0079] Figure 4 yes B oilfield B1 Results of fracture porosity, total porosity calculated by well logging, and total permeability calculated by well logging in the fractured reservoir with more developed fractures in the buried hill:

[0080] Track 1 is the measured depth of the formation;

[0081] The second track is the natural gamma and well diameter, indicating the lithologic characteristics of the formation;

[0082] The third track is the deep and shallow resistivity logging curves, which depict the electrical characteristics of the formation;

[0083] Track 4 is the volume density, neutron porosity and acoustic transit time, reflecting the physical properties of the formation;

[0084] Track 5 is fracture porosity;

[0085] Track 6 is the full-diameter, plug-core analysis porosity;

[0086] Track 7 is the sum of the plug core analysis porosity and the fracture porosity, the plug core analysis porosity;

[0087] Track 8 is the total porosity from core analysis (including the sum of the porosity from full-diameter core analysis, the porosity from plug core analysis, and the porosity from fractures) and the total porosity calculated from well logging;

[0088] Track 9 is the permeability of the full-diameter core analysis and the total permeability calculated by well logging;

[0089] Track 10 shows the contents of sandstone, dolomite, limestone and mudstone calculated by well logging.

[0090] From the 9th track, we can see that the permeability of the full-diameter core analysis, that is, the total permeability of the core analysis, is in good agreement with the permeability calculated by Stoneley wave in step 4), that is, the total permeability calculated by well logging, indicating that the total permeability calculated by well logging is highly accurate. From step 2), we can see that B Limit values ​​of permeability of full-diameter core analysis and plug core analysis in oil fields D =1.0mD; while the total permeability calculated by well logging is basically greater than 1.0mD, indicating that Figure 4 shown B oilfield B1 The fractured reservoirs in the buried hill have effective fractures. Therefore, in addition to the porosity analysis of the full-diameter core (with relatively few data points), B oilfield B1 The total porosity of the fractured reservoir in the buried hill is equal to the sum of the porosity of the plunger core analysis (relatively more data points) and the fracture porosity, see Figure 4 Track 7. Track 8 shows the absolute error between the total porosity from core analysis (including the sum of the porosity from full-diameter core analysis, the porosity from plug core analysis, and the porosity from fractures) and the total porosity calculated from well logging, which is 4.05%. The absolute error between the porosity from plug core analysis and the total porosity calculated from well logging is 8.04%.

[0091] when K t ﹤ D When the porosity is calculated in step 5) φ t The porosity should be analyzed with the plunger core in step 1). φ mc The error between them is minimal.

[0092] Figure 5 yes A oilfield A2 Results of fracture porosity, total porosity calculated by well logging, and total permeability calculated by well logging in the fractured reservoir section with no fractures in the buried hill:

[0093] Track 1 is the measured depth of the formation;

[0094] The second track is the natural gamma and well diameter, indicating the lithologic characteristics of the formation;

[0095] The third track is the deep and shallow resistivity logging curves, which depict the electrical characteristics of the formation;

[0096] Track 4 is the volume density, neutron porosity and acoustic transit time, reflecting the physical properties of the formation;

[0097] Track 5 is fracture porosity;

[0098] Track 6 is the full-diameter, plug-core analysis porosity;

[0099] Track 7 is the total porosity from core analysis (including porosity from full-diameter core analysis and plunger core analysis) and the total porosity calculated from well logging;

[0100] Track 8 is the permeability of the full-diameter core analysis and the total permeability calculated by well logging;

[0101] Track 9 is the content of quartz, feldspar and mica calculated by well logging.

[0102] From the 8th channel, we can see that the full diameter core analysis permeability, that is, the total core analysis permeability, is in good agreement with the Stoneley wave permeability calculated in step 4), that is, the total permeability calculated by well logging, indicating that the total permeability calculated by well logging is highly accurate. From step 2), we can see that A Limit values ​​of permeability of full-diameter core analysis and plug core analysis in oil fields D =0.1mD; while the total permeability calculated by well logging is basically less than 0.1mD, indicating that Figure 5 shown A oilfield A1 The fractured reservoirs in the buried hill have no fractures or have ineffective fractures. Therefore, the porosity from both full-diameter and plug core analysis is total porosity, as shown in Track 7. The absolute error between the total porosity from core analysis and the total porosity calculated from well logging is 4.96%.

[0103] Figure 6 yes B oilfield B1 Results of fracture porosity in the fractured interval of the buried hill fracture reservoir where fractures are not developed, total porosity calculated by well logging, and total permeability calculated by well logging.

[0104] Track 1 is the measured depth of the formation;

[0105] The second track is the natural gamma and well diameter, indicating the lithologic characteristics of the formation;

[0106] The third track is the deep and shallow resistivity logging curves, which depict the electrical characteristics of the formation;

[0107] Track 4 is the volume density, neutron porosity and acoustic transit time, reflecting the physical properties of the formation;

[0108] Track 5 is fracture porosity;

[0109] Track 6 is the porosity from the plunger core analysis;

[0110] Track 7 is the sum of the plug core analysis porosity and the fracture porosity;

[0111] Track 8 is the total porosity from core analysis (the sum of the porosity from plug core analysis and the porosity from fractures) and the total porosity calculated from well logging;

[0112] Track 9 is the total permeability calculated from the well logging;

[0113] Track 10 shows the contents of sandstone, dolomite, limestone and mudstone calculated by well logging.

[0114] From question 9, we can see that from step 2) B Limit values ​​of permeability of full-diameter core analysis and plug core analysis in oil fields D =1.0mD.

[0115] exist Figure 6 In the buried hill fracture reservoir section I, the total permeability calculated by well logging is basically less than 1.0mD, indicating that there are no fractures or ineffective fractures in the buried hill fracture reservoir section; therefore, the porosity of the plunger core analysis is the total porosity. Figure 6 In the buried-hill fractured reservoir interval II, the total permeability calculated by well logging is generally greater than 1.0 mD, indicating the presence of effective fractures in this buried-hill fractured reservoir interval. Therefore, the sum of the porosity from the plug core analysis and the fracture porosity is the total porosity. The absolute error between the total porosity from the core analysis in Track 8 and the total porosity calculated by well logging is 1.50%.

[0116] A second aspect of the present invention provides a porosity calibration device for well logging of a buried-hill fractured reservoir, comprising:

[0117] The first processing unit is used to perform physical property analysis based on full-diameter core samples and plunger core samples at a certain depth of the buried hill fracture reservoir of the oil and gas field to obtain the porosity and permeability of the full-diameter core samples and plunger core samples;

[0118] The second processing unit is used to construct a cross-plot of the porosity and permeability of the full-diameter core sample and the plug core sample of the buried-hill fractured reservoir of the oil and gas field based on the porosity and permeability of the full-diameter core sample and the plug core sample, and determine the limit values ​​of the permeability of the full-diameter core sample and the permeability of the plug core sample according to the distribution range of the permeability of the full-diameter core sample and the permeability of the plug core sample in the cross-plot;

[0119] The third processing unit is configured to calculate the fracture porosity of the buried hill fracture reservoir of the oil and gas field based on the well logging data of the buried hill fracture reservoir of the oil and gas field;

[0120] The fourth processing unit is configured to calculate the permeability of the buried hill fractured reservoir of the oil and gas field based on the well logging data of the buried hill fractured reservoir of the oil and gas field;

[0121] A fifth processing unit is configured to calculate the logging porosity of the buried-hill fractured reservoir in the oil and gas field based on the logging data of the buried-hill fractured reservoir in the oil and gas field;

[0122] The sixth processing unit is used to compare the calculated permeability of the fractured reservoir in the buried hill of the oil and gas field with the limit values ​​of the permeability of the full-diameter core sample and the permeability of the plunger core sample, to determine the development of the fractured reservoir in the buried hill of the oil and gas field and the error between the logging porosity and the fracture porosity and the porosity of the plunger core sample.

[0123] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the computer program implements the steps of any one of the above-mentioned methods for calibrating the porosity of buried-hill fractured reservoir logging.

[0124] A fourth aspect of the present invention provides a computer 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 any one of the above-mentioned methods for calibrating the porosity of buried-hill fractured reservoir logging are implemented.

[0125] The present invention is described based on flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to specific embodiments. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0126] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0127] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0128] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for calibrating the porosity of buried-hill fractured reservoir logging, characterized in that: include: Physical property analysis is conducted on full-diameter core samples and plug core samples taken at a certain depth from fractured reservoirs in buried hills of oil and gas fields to obtain the porosity and permeability of the full-diameter core samples and plug core samples. Based on the porosity and permeability of full-diameter core samples and plug core samples, a crossplot of the porosity and permeability of full-diameter core samples and plug core samples in the buried-hill fractured reservoir of the oil and gas field was constructed. Based on the distribution range of the permeability of the full-diameter core samples and the permeability of the plug core samples in the crossplot, the boundary values ​​of the permeability of the full-diameter core samples and the permeability of the plug core samples were determined; Based on the well logging data of the fractured reservoirs in the buried hills of oil and gas fields, the fracture porosity of the fractured reservoirs in the buried hills of oil and gas fields is calculated; Based on the well logging data of the fractured reservoir in the buried hill of the oil and gas field, the permeability of the fractured reservoir in the buried hill of the oil and gas field is calculated; Based on the logging data of the fractured reservoir in the buried hill of the oil and gas field, the logging porosity of the fractured reservoir in the buried hill of the oil and gas field is calculated; By comparing the calculated permeability of the fractured reservoir in the buried hill of the oil and gas field with the limit values ​​of the permeability of the full-diameter core sample and the permeability of the plunger core sample, the development of the fractured reservoir in the buried hill of the oil and gas field and the error size between the logging porosity and the fracture porosity and the porosity of the plunger core sample can be judged.

2. The method for calibrating the porosity of buried-hill fractured reservoir logging according to claim 1, characterized in that: Well logging data include natural gamma ray, natural potential, deep resistivity, medium resistivity, shallow resistivity, bulk density, neutron porosity, compressional wave transit time, shear wave transit time, Stoneley wave transit time and electrical imaging.

3. The method for calibrating the porosity of buried-hill fractured reservoir logging according to claim 1, characterized in that: Based on the well logging data of the buried-hill fractured reservoirs in the oil and gas fields, the fracture porosity of the buried-hill fractured reservoirs in the oil and gas fields is calculated. The calculation formula of the fracture porosity is as follows: Where: φ f is the fracture porosity; m f is the fracture porosity index; R m is the mud resistivity; R s is the shallow lateral resistivity; K f is the crack distortion coefficient; R d is the deep lateral resistivity.

4. The method for calibrating the porosity of buried-hill fractured reservoir logging according to claim 1, characterized in that: Based on the well logging data of the fractured reservoir in the buried hill of the oil and gas field, the permeability of the fractured reservoir in the buried hill of the oil and gas field is calculated. The calculation formula of the permeability is as follows: Where: K t is the well logging permeability; is the frequency shift of Stoneley waves; is the time lag of the Stoneley wave.

5. The method for calibrating the porosity of buried-hill fractured reservoir logging according to claim 1, characterized in that: Based on the logging data of the fractured reservoir in the buried hill of the oil and gas field, the logging porosity of the fractured reservoir in the buried hill of the oil and gas field is calculated. The calculation formula of the logging porosity is as follows: Where: φ t is the well logging porosity; GR is natural gamma; R t is the deep resistivity; R xo is the resistivity of the flushing zone; DEN is the bulk density; NPHI is the neutron porosity; DT is the longitudinal wave time difference.

6. The method for calibrating the porosity of buried-hill fractured reservoir logging according to claim 1, characterized in that: The permeability of the fractured reservoir in the buried hill of the oil and gas field is compared with the limit values ​​of the permeability of the full-diameter core sample and the permeability of the plunger core sample to judge the development of the fractured reservoir in the buried hill of the oil and gas field and the error between the logging porosity and the fracture porosity and the porosity of the plunger core sample, as follows: When the calculated permeability of the buried-hill fractured reservoir in an oil and gas field is greater than or equal to the limit value of the permeability of the full-diameter core sample and the permeability of the plunger core sample, it indicates that effective fractures are developed in the buried-hill fractured reservoir; otherwise, it indicates that no fractures are developed in the buried-hill fractured reservoir or ineffective fractures are developed.

7. The method for calibrating the porosity of buried-hill fractured reservoir logging according to claim 6, characterized in that: When the calculated permeability of the fractured reservoir in the buried hill of an oil and gas field is greater than or equal to the limit value of the permeability of the full-diameter core sample and the permeability of the plunger core sample, the error between the logging porosity and the sum of the fracture porosity and the porosity of the plunger core sample is minimized.

8. A porosity calibration device for well logging of buried hill fractured reservoirs, characterized in that: include: The first processing unit is used to perform physical property analysis based on full-diameter core samples and plunger core samples at a certain depth of the buried hill fracture reservoir of the oil and gas field to obtain the porosity and permeability of the full-diameter core samples and plunger core samples; The second processing unit is used to construct a cross-plot of the porosity and permeability of the full-diameter core sample and the plug core sample of the buried-hill fractured reservoir of the oil and gas field based on the porosity and permeability of the full-diameter core sample and the plug core sample, and determine the limit values ​​of the permeability of the full-diameter core sample and the permeability of the plug core sample according to the distribution range of the permeability of the full-diameter core sample and the permeability of the plug core sample in the cross-plot; The third processing unit is configured to calculate the fracture porosity of the buried hill fracture reservoir of the oil and gas field based on the well logging data of the buried hill fracture reservoir of the oil and gas field; The fourth processing unit is configured to calculate the permeability of the buried hill fractured reservoir of the oil and gas field based on the well logging data of the buried hill fractured reservoir of the oil and gas field; A fifth processing unit is configured to calculate the logging porosity of the buried-hill fractured reservoir in the oil and gas field based on the logging data of the buried-hill fractured reservoir in the oil and gas field; The sixth processing unit is used to compare the calculated permeability of the fractured reservoir in the buried hill of the oil and gas field with the limit values ​​of the permeability of the full-diameter core sample and the permeability of the plunger core sample, to determine the development of the fractured reservoir in the buried hill of the oil and gas field and the error between the logging porosity and the fracture porosity and the porosity of the plunger core sample.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for calibrating the porosity of a buried hill fractured reservoir by well logging are realized as described in any one of claims 1 to 7.

10. A computer 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 for calibrating the porosity of a buried hill fractured reservoir by well logging are implemented as described in any one of claims 1 to 7.

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