Methods and apparatus for detecting porosity based on rock hardness

Abstract

This invention discloses a method and apparatus for porosity detection based on rock hardness. The method includes: collecting circular plunger samples of different types of rocks, measuring their hardness, and determining the correlation between hardness and density for each type of rock sample; inputting a preset ideal density for each type of rock sample into the corresponding hardness-density correlation formula to obtain an ideal hardness threshold; comparing the hardness of the rock sample to be tested with the corresponding ideal hardness threshold to obtain a comparison result and calculating a hardness correction coefficient; establishing a cross-plot based on the measured hardness and corresponding porosity of each type of rock sample; and determining the correlation between hardness and porosity for each type of rock sample based on the cross-plot and the hardness correction coefficient to obtain the porosity of the rock sample to be tested. This invention can reduce the size and shape requirements of the porosity detection samples and improve the detection efficiency.

Description

Technical Field

[0001] This invention relates to the field of oil and gas exploration technology, and in particular to a method and apparatus for detecting porosity based on rock hardness. Background Technology

[0002] This section is intended to provide background or context for the embodiments of the invention set forth in the claims. The description herein is not an admission that it is prior art simply because it is included in this section.

[0003] In reservoir evaluation during oil and gas exploration, reservoir porosity parameters can be obtained based on porosity testing of rock samples. For rock samples, circular plungers can be drilled from cores using a fixed sampling machine in the laboratory. However, due to limitations in the degree of core fragmentation, it is often impossible to obtain a sufficient number of standard circular plungers. For outcrop samples, the current requirement for large hand specimen sizes increases the difficulty of obtaining circular plunger samples, especially on relatively smooth rock walls. This results in insufficient formation porosity data and low porosity testing efficiency due to the difficulty in obtaining circular plunger samples from outcrops or fragile cores. Therefore, there is an urgent need for a porosity testing method that can reduce the requirements for rock samples, achieve accurate and rapid rock porosity testing, and lay the foundation for reservoir geological evaluation. Summary of the Invention

[0004] This invention provides a method for porosity detection based on rock hardness to improve the efficiency of porosity detection. The porosity detection results based on this method can effectively guide reservoir geological evaluation. The method includes:

[0005] Collect circular rock plunger samples of different types, measure the hardness of each type of circular rock plunger sample, and determine the correlation between the hardness and density of each type of circular rock plunger sample.

[0006] Input the preset ideal density of each type of rock sample into the correlation formula between hardness and density of the corresponding type to obtain the output ideal hardness threshold of each type of rock sample; compare the hardness of the rock sample to be tested with the ideal hardness threshold of the corresponding type to obtain the comparison result; calculate the hardness correction coefficient based on the comparison result, the output density of the rock sample hardness of each type of rock sample to be tested, and the output preset ideal density hardness threshold.

[0007] Based on the measured hardness and corresponding porosity of each type of rock circular plunger sample, a cross-plot of hardness and porosity for the corresponding rock sample is established.

[0008] Based on the cross plot, the correlation between hardness and porosity of each type of rock sample was determined; the correlation between hardness and porosity of the corresponding rock sample was corrected based on the hardness correction coefficient.

[0009] The hardness of the rock sample to be tested is input into the corrected correlation formula between hardness and porosity of the corresponding type of rock sample to obtain the porosity of the rock sample to be tested.

[0010] This invention also provides a porosity detection device based on rock hardness, which reduces the requirements for test samples, improves the efficiency of porosity detection, and can effectively guide reservoir geological evaluation based on the porosity detection results. The device includes:

[0011] The module for determining the relationship between hardness and density is used to collect circular rock plunger samples of different types, measure the hardness of each type of circular rock plunger sample, and determine the correlation between the hardness and density of each type of circular rock plunger sample.

[0012] The hardness correction coefficient calculation module is used to input the preset ideal density of each type of rock sample into the correlation formula between hardness and density of the corresponding type to obtain the output ideal hardness of each type of rock sample; compare the hardness of the rock sample to be tested with the ideal hardness threshold of the corresponding type to obtain the comparison result; and calculate the hardness correction coefficient based on the comparison result.

[0013] The cross plot creation module is used to create a cross plot of the hardness and porosity of each type of rock circular plunger sample based on the measured hardness and corresponding porosity.

[0014] The module for determining the relationship between hardness and porosity is used to determine the correlation between hardness and porosity for each type of rock sample based on the cross-plot; and to correct the correlation between hardness and porosity for the corresponding type of rock sample based on the hardness correction coefficient.

[0015] The porosity determination module for the rock sample under test is used to input the hardness of the rock sample under test into the corrected correlation formula between the hardness and porosity of the corresponding type of rock sample to obtain the porosity of the rock sample under test.

[0016] This invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the above-described method for detecting porosity based on rock hardness.

[0017] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for detecting porosity based on rock hardness.

[0018] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the above-described porosity detection method based on rock hardness.

[0019] In this embodiment of the invention, different types of circular rock plunger samples are collected, and the hardness of each type of circular rock plunger sample is measured to determine the correlation between hardness and density for each type of circular rock plunger sample. A preset ideal density for each type of rock sample is input into the corresponding hardness-density correlation formula to obtain the output ideal hardness threshold for each type of rock sample. The hardness of the rock sample to be tested is compared with the corresponding ideal hardness threshold to obtain the comparison result. Based on the comparison result, the output density of the rock sample hardness of each type of rock sample to be tested, and the output preset ideal density-hardness threshold, a hardness correction coefficient is calculated. Based on the measured hardness and corresponding porosity of each type of circular rock plunger sample, a cross-plot of hardness and porosity for the corresponding rock sample is established. Based on the cross-plot, the correlation between hardness and porosity for each type of rock sample is determined. The correlation between hardness and porosity for the corresponding type of rock sample is corrected based on the hardness correction coefficient. The hardness of the rock sample to be tested is input into the corrected correlation between hardness and porosity for the corresponding type of rock sample to obtain the porosity of the rock sample to be tested. Based on the above, this embodiment of the invention introduces rock sample hardness, and based on the determined relationship between rock sample hardness and density, correction coefficient, and cross-plot of hardness and porosity, determines the relationship between hardness and porosity. Through the above relationship between hardness and porosity, the porosity detection efficiency is improved, and the porosity detection results can effectively guide reservoir geological evaluation. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0021] Figure 1 This is a flowchart of a porosity detection method based on rock hardness in an embodiment of the present invention;

[0022] Figure 2 This is a flowchart illustrating the calculation of the average hardness of a rock sample in an embodiment of the present invention;

[0023] Figure 3 This is a diagram showing the porosity results for each sample in this embodiment of the invention.

[0024] Figure 4 This is a schematic diagram of a porosity detection device based on rock hardness in an embodiment of the present invention;

[0025] Figure 5 This is a schematic diagram of a computer device in an embodiment of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0027] Figure 1 This is a flowchart of a porosity detection method based on rock hardness in an embodiment of the present invention. The method includes:

[0028] Step 101: Collect different types of rock circular plunger samples, measure the hardness of each type of rock circular plunger sample, and determine the correlation between the hardness and density of each type of rock circular plunger sample.

[0029] Step 102: Input the preset ideal density of each type of rock sample into the correlation formula between hardness and density of the corresponding type to obtain the output ideal hardness threshold of each type of rock sample; compare the hardness of the rock sample to be tested with the ideal hardness threshold of the corresponding type to obtain the comparison result; calculate the hardness correction coefficient based on the comparison result, the output density of the rock sample hardness of each type of rock sample to be tested, and the output preset ideal density hardness threshold.

[0030] Step 103: Based on the measured hardness and corresponding porosity of each type of rock circular plunger sample, establish a cross-plot of hardness and porosity for the corresponding rock sample.

[0031] Step 104: Based on the cross plot, determine the correlation between hardness and porosity for each type of rock sample; correct the correlation between hardness and porosity for the corresponding type of rock sample based on the hardness correction coefficient.

[0032] Step 105: Input the hardness of the rock sample to be tested into the corrected correlation formula between hardness and porosity of the corresponding type of rock sample to obtain the porosity of the rock sample to be tested.

[0033] Each step is described in detail below.

[0034] In step 101, different types of rock circular plunger samples are collected, the hardness of each type of rock circular plunger sample is measured, and the correlation between the hardness and density of each type of rock circular plunger sample is determined.

[0035] Figure 2 This is a flowchart illustrating the calculation of the average hardness of rock samples in an embodiment of the present invention. In one embodiment, before determining the correlation between hardness and density of each type of circular plunger rock sample, the following steps are included:

[0036] Step 201: Measure the hardness of each type of rock circular plunger sample multiple times to obtain the hardness measurement value of the rock circular plunger sample for each measurement.

[0037] Step 202: Using the tail-cutting mean method, the average hardness of each type of rock circular plunger sample is calculated based on the measured hardness values ​​of the rock circular plunger samples; in a specific embodiment, the process for calculating the average hardness of the rock sample to be tested is the same as the above process.

[0038] Determine the correlation between hardness and density for each type of rock circular plunger sample, including:

[0039] Based on the average hardness and known density of the circular rock plunger samples of each type, the correlation formula between the hardness and density of the circular rock plunger samples of each type is determined.

[0040] In one embodiment, the relationship between the hardness and density of the rock circular plunger sample is as follows:

[0041] UCS = k × DEN + b

[0042] Where UCS is the hardness of the rock circular plunger sample, DEN is the density of the rock circular plunger sample, and k and b are constants.

[0043] In a specific embodiment, the hardness measurement process for the rock sample and the rock circular plunger sample is the same. Both are measured using a Leeb hardness tester to obtain the rock hardness UCS (unit HL). During measurement, the rock sample or rock circular plunger sample is first placed on a horizontal ground or table. One hand holds the handheld Leeb hardness tester vertically and firmly against the surface of the rock sample, while the other hand presses the release button for the impact ball. The impact ball strikes the surface of the rock sample, and the instrument automatically displays the measured rock hardness value and records the value. Multiple measurements are performed to eliminate errors. The rock hardness is measured 7 times, and the value is recorded each time (during measurement, hand tremors or incomplete contact between the hardness tester and the sample surface may cause measurement errors. To minimize these errors, multiple measurements are necessary. Based on experience, 7 measurements provide the best timeliness; the time for a normal measurement and recording of the hardness value is approximately 10 seconds). The average rock hardness UCS is calculated using the tail-cutting mean method. ave Among them, the truncated mean method can eliminate outliers in the dataset, thereby reducing the impact of measurement manipulation and making the statistical data more reasonable and robust.

[0044] In step 102, the preset ideal density of each type of rock sample is input into the correlation formula between hardness and density of the corresponding type to obtain the ideal hardness threshold output for each type of rock sample; the hardness of the rock sample to be tested is compared with the ideal hardness threshold of the corresponding type to obtain the comparison result; based on the comparison result, the output density of the rock sample hardness of each type of rock sample to be tested, and the output preset ideal density hardness threshold, the hardness correction coefficient is calculated.

[0045] In a specific embodiment, after measuring the hardness of the rock circular plunger sample, the average rock hardness (UCS) is calculated. ave A binary scatter plot of hardness and density (DEN) was used, and linear regression was performed to obtain the correlation formula between hardness and density for rock samples of different rock types, for example:

[0046] Mudstone: UCS ave =301.22 × DEN - 315.4;

[0047] Sandstone: UCS ave =338.12 × DEN - 409.64;

[0048] Limestone: UCS ave =460.83 × DEN - 737.68;

[0049] Baiyunyan: UCS ave =506.59×DEN-864.04.

[0050] In step 103, based on the measured hardness and corresponding porosity of each type of rock circular plunger sample, a cross-plot of hardness and porosity for the corresponding rock sample is established.

[0051] In one embodiment, the correlation between hardness and porosity of rock samples of the corresponding type is corrected based on a hardness correction coefficient, including: the ideal hardness threshold includes a maximum ideal hardness threshold and a minimum ideal hardness threshold;

[0052] Input the preset ideal density of each type of rock sample into the corresponding hardness-density correlation formula to obtain the ideal hardness threshold output for each type of rock sample.

[0053] When the output hardness of any type of rock sample is less than the minimum ideal hardness threshold, or when the output hardness of any type of rock sample is greater than the maximum ideal hardness threshold, the correlation between hardness and porosity of the corresponding type of rock sample is corrected based on the correction coefficient.

[0054] In one embodiment, based on the comparison results, the output density of the rock sample hardness for each type of rock sample, and the preset ideal density-hardness threshold, a hardness correction coefficient is calculated, including:

[0055] When the output hardness of any type of rock sample is less than the minimum ideal hardness threshold, the correction coefficient is:

[0056] a = 1 + (UCS) min -UCS ave ) / UCS min

[0057] When the output hardness of any type of rock sample exceeds the maximum ideal hardness threshold, the correction coefficient is:

[0058] a = 1 - (UCS) max -UCS ave ) / UCS max

[0059] Where a is the correction coefficient, UCS min UCS is the minimum ideal hardness threshold. max UCS is the maximum ideal hardness threshold. ave Output hardness for rock samples.

[0060] In a specific embodiment, based on experience, the density of mudstone is typically between 2.10 and 2.55 g / cm³. 3 The density of sandstone is typically between 2.20 and 2.65 g / cm³. 3 The density of limestone is typically between 2.50 and 2.72 g / cm³. 3 The density of dolomite is typically between 2.60 and 2.87 g / cm³. 3 The maximum and minimum rock hardness of the mudstone were obtained from the density, and were respectively UCS. max =452.7, UCS min =317.2, the maximum and minimum rock hardness of sandstone are UCS respectively. max =486.4, UCS min =334.2, the maximum and minimum rock hardness of limestone are UCS. max =515.8UCS min =414.4, the maximum and minimum rock hardness of dolomite are UCS. max =589.9, UCS min =453.1. Then, compare and analyze whether the output density of the rock sample is between the known minimum ideal density threshold and maximum ideal density threshold for the corresponding rock type. When a certain type of rock satisfies the UCS... ave <UCS minThen the correlation formula between hardness and density needs to be corrected; when a certain type of rock satisfies UCS min ≤UCS ave ≤UCS max Then there is no need to correct the correlation between hardness and density; when a certain type of rock satisfies UCS ave >UCS max Therefore, it is necessary to correct the correlation between hardness and density.

[0061] In step 104, the correlation between hardness and porosity of each type of rock sample is determined based on the cross plot; the correlation between hardness and porosity of the corresponding type of rock sample is corrected based on the hardness correction coefficient.

[0062] In one embodiment, the correlation between hardness and porosity for each type of rock sample is as follows:

[0063] POR = α × ln(UCS) ave )+β

[0064] Where POR is the porosity of the rock sample, and UCS is the porosity of the rock sample. ave denoted as the output density of the rock sample, and α and β as regression coefficients.

[0065] In a specific embodiment, after establishing the cross-plot of hardness versus porosity for the corresponding rock sample, the logarithmic relationship between hardness and porosity is obtained:

[0066] POR = -34.63 × ln(UCS) ave +219.89

[0067] Then, based on the porosity correction factor 'a', the final porosity calculation formula is obtained:

[0068] POR = a × (-34.63 × ln(UCS)) ave )+219.89)

[0069] In step 105, the hardness of the rock sample to be tested is input into the corrected correlation formula between the hardness and porosity of the corresponding type of rock sample to obtain the porosity of the rock sample to be tested.

[0070] In a specific embodiment, the process of collecting suitable rock samples for testing is as follows: ① Determine the sample size. Samples with a length, width, and height greater than 1.5cm, 1.5cm, and 2.5cm respectively (since the diameter of the contact surface between the hardness tester and the sample is about 1cm, and considering the irregularity of the sample, a length and width greater than 1.5cm is more suitable for rock samples; according to the hardness test analysis of standard plunger rock samples, it was found that the hardness error of each measurement is smaller when the sample height is above 2cm, because the sample will be cut from top to bottom later, so the sample height should be above 2.5cm). ② Determine the rock type of the sample. Rock hardness and density have a good correlation. Different lithologies have different densities. Common sedimentary rocks mainly include limestone, dolomite, sandstone, mudstone, etc. 5% dilute hydrochloric acid is used to distinguish limestone and dolomite, which are difficult to identify with the naked eye (limestone will strongly effervesce after acid is added, while dolomite will not effervesce or will effervesce weakly). ③ Determine the sample composite measurement requirements. Use an indoor rock cutter to cut the sample horizontally (the bottom should be in horizontal contact with the table and the top with the hardness tester; otherwise, the measurement error will be large), and try to make the height of the processed sample greater than 2cm.

[0071] In a specific embodiment, taking a basin stratum as an example, the strata in this profile are 130.8m thick. Originally, 70 cylindrical samples were collected for rock porosity measurement, with an average spacing of approximately one sample every 2m. This might not accurately reflect the porosity variation patterns of the strata. To make the porosity variation characteristics of this profile more accurate, supplementary and denser sampling was conducted above and below the original sampling points, resulting in the collection of 119 irregular hand specimens. First, all samples were identified by dilute hydrochloric acid, confirming that all 119 samples were dolomite. Then, the samples were pretreated to meet the rock hardness measurement standards. Finally, rock hardness measurements were performed on the samples, obtaining the UCS of all samples. ave The porosity of each sample was finally calculated after correction. Figure 3 This is a porosity result diagram for each sample in the embodiments of the present invention. From Figure 3 It can be seen that the porosity variation trend obtained based on rock hardness (rhomboid black dots) is basically consistent with the porosity variation trend obtained based on the actual measurement of the circular plunger (circular gray dots), indicating that the porosity detection method based on rock hardness is reliable. Due to the increased sample quantity, the previously sparse porosity data has been supplemented, more realistically reflecting the variation characteristics of formation porosity, laying the foundation for reservoir quality evaluation and vertical distribution pattern prediction (based on the analysis of 189 samples, the average porosity is 3.24%, the maximum porosity is 14.73%, and the proportion of samples with porosity greater than 2.5% is 48.7%, indicating that the overall reservoir quality is good and has a certain scale. At the same time, it is clear that high-quality reservoirs with porosity >2.5% are mainly developed in the top, middle and lower parts).

[0072] This invention also provides a porosity detection device based on rock hardness, as described in the following embodiments. Since the principle by which this device solves the problem is similar to that of the porosity detection method based on rock hardness, the implementation of this device can refer to the implementation of the porosity detection method based on rock hardness; repeated details will not be elaborated further.

[0073] Figure 4 This is a schematic diagram of a porosity detection device based on rock hardness according to an embodiment of the present invention. The device includes:

[0074] The module 401 for determining the relationship between hardness and density is used to collect circular rock plunger samples of different types, measure the hardness of each type of circular rock plunger sample, and determine the correlation between the hardness and density of each type of circular rock plunger sample.

[0075] The hardness correction coefficient calculation module 402 is used to input the preset ideal density of each type of rock sample into the correlation formula between hardness and density of the corresponding type to obtain the output ideal hardness of each type of rock sample; compare the hardness of the rock sample to be tested with the ideal hardness threshold of the corresponding type to obtain the comparison result; and calculate the hardness correction coefficient based on the comparison result.

[0076] The cross plot creation module 403 is used to create a cross plot of the hardness and porosity of the corresponding rock sample based on the measured hardness and corresponding porosity of each type of rock circular plunger sample.

[0077] The module 404 for determining the relationship between hardness and porosity is used to determine the correlation between hardness and porosity for each type of rock sample based on the cross plot; and to correct the correlation between hardness and porosity for the corresponding type of rock sample based on the hardness correction coefficient.

[0078] The porosity determination module 405 for the rock sample to be tested is used to input the hardness of the rock sample to be tested into the corrected correlation formula between the hardness and porosity of the corresponding type of rock sample to obtain the porosity of the rock sample to be tested.

[0079] In one embodiment, the hardness-density relationship determination module 401 is specifically used for:

[0080] The hardness of each type of rock circular plunger sample was measured multiple times to obtain the hardness measurement value of the rock circular plunger sample for each measurement.

[0081] The average hardness of each type of rock circular plunger sample was calculated using the tail-cutting mean method based on the measured hardness values ​​of the rock circular plunger samples.

[0082] Determine the correlation between hardness and density for each type of rock circular plunger sample, including:

[0083] Based on the average hardness and known density of the circular rock plunger samples of each type, the correlation formula between the hardness and density of the circular rock plunger samples of each type is determined.

[0084] In one embodiment, the relationship between the hardness and density of the rock circular plunger sample is as follows:

[0085] UCS = k × DEN + b

[0086] Where UCS is the hardness of the rock circular plunger sample, DEN is the density of the rock circular plunger sample, and k and b are constants.

[0087] In one embodiment, the hardness correction coefficient calculation module 402 is specifically used for:

[0088] The correlation between hardness and porosity of rock samples of the corresponding type is corrected based on the hardness correction coefficient. The ideal hardness threshold includes the maximum ideal hardness threshold and the minimum ideal hardness threshold.

[0089] Input the preset ideal density of each type of rock sample into the corresponding hardness-density correlation formula to obtain the ideal hardness threshold output for each type of rock sample.

[0090] When the output hardness of any type of rock sample is less than the minimum ideal hardness threshold, or when the output hardness of any type of rock sample is greater than the maximum ideal hardness threshold, the correlation between hardness and porosity of the corresponding type of rock sample is corrected based on the correction coefficient.

[0091] In one embodiment, the hardness correction coefficient calculation module 402 is specifically used for:

[0092] When the output hardness of any type of rock sample is less than the minimum ideal hardness threshold, the correction coefficient is:

[0093] a = 1 + (UCS) min -UCS ave ) / UCS min

[0094] When the output hardness of any type of rock sample exceeds the maximum ideal hardness threshold, the correction coefficient is:

[0095] a = 1 - (UCS) max -UCS ave ) / UCS max

[0096] Where a is the correction coefficient, UCS min UCS is the minimum ideal hardness threshold. max UCS is the maximum ideal hardness threshold. aveOutput hardness for rock samples.

[0097] In one embodiment, the correlation between hardness and porosity for each type of rock sample is as follows:

[0098] POR = α × ln(UCS) ave )+β

[0099] Where POR is the porosity of the rock sample, and UCS is the porosity of the rock sample. ave α represents the output hardness of the rock sample, and β represents the regression coefficients.

[0100] This invention also provides a computer device. Figure 5 This is a schematic diagram of a computer device in an embodiment of the present invention. The computer device 500 includes a memory 510, a processor 520, and a computer program 530 stored in the memory 510 and executable on the processor 520. When the processor 520 executes the computer program 530, it implements the above-mentioned porosity detection method based on rock hardness.

[0101] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for detecting porosity based on rock hardness.

[0102] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the above-described porosity detection method based on rock hardness.

[0103] In this embodiment of the invention, different types of circular rock plunger samples are collected, and the hardness of each type of circular rock plunger sample is measured to determine the correlation between hardness and density for each type of circular rock plunger sample. The preset ideal density of each type of rock sample is input into the corresponding hardness-density correlation formula to obtain the ideal hardness threshold for each type of rock sample. The hardness of the rock sample to be tested is compared with the ideal hardness threshold for the corresponding type to obtain the comparison result. Based on the comparison result, a hardness correction coefficient is calculated. Based on the measured hardness and corresponding porosity of each type of circular rock plunger sample, a cross-plot of hardness and porosity for the corresponding rock sample is established. Based on the cross-plot, the correlation between hardness and porosity for each type of rock sample is determined. The correlation between hardness and porosity for the corresponding type of rock sample is corrected based on the hardness correction coefficient. The hardness of the rock sample to be tested is input into the corrected correlation between hardness and porosity for the corresponding type of rock sample to obtain the porosity of the rock sample to be tested. Based on the above, this embodiment of the invention introduces rock sample hardness, and based on the determined relationship between rock sample hardness and density, correction coefficient, and cross-plot of hardness and porosity, determines the relationship between hardness and porosity. The porosity detection results obtained through the above relationship between hardness and porosity can improve the efficiency of porosity detection and effectively guide reservoir geological evaluation.

[0104] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0105] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations 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, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0106] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0107] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0108] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for detecting porosity based on rock hardness, characterized by, include: Collect circular rock plunger samples of different types, measure the hardness of each type of circular rock plunger sample, and determine the correlation between the hardness and density of each type of circular rock plunger sample. The preset ideal density of each type of rock sample is input into the correlation formula between hardness and density of the corresponding type to obtain the ideal hardness threshold output for each type of rock sample; the hardness of the rock sample to be tested is compared with the ideal hardness threshold of the corresponding type to obtain the comparison result; based on the comparison result, the hardness correction coefficient is calculated. Based on the measured hardness and corresponding porosity of each type of rock circular plunger sample, a cross-plot of hardness and porosity for the corresponding rock sample is established. Based on the cross plot, determine the correlation between hardness and porosity for each type of rock sample; The correlation between hardness and porosity of rock samples of the corresponding type is corrected based on the hardness correction coefficient. The hardness of the rock sample to be tested is input into the corrected correlation formula between hardness and porosity of the corresponding type of rock sample to obtain the porosity of the rock sample to be tested.

2. The method of claim 1, wherein, Before determining the correlation between hardness and density for each type of rock circular plunger sample, the following steps are included: The hardness of each type of rock circular plunger sample was measured multiple times to obtain the hardness measurement value of the rock circular plunger sample for each measurement. The average hardness of each type of rock circular plunger sample was calculated using the tail-cutting mean method based on the measured hardness values ​​of the rock circular plunger samples. Determine the correlation between hardness and density for each type of rock circular plunger sample, including: Based on the average hardness and known density of the circular rock plunger samples of each type, the correlation formula between the hardness and density of the circular rock plunger samples of each type is determined.

3. The method as described in claim 2, characterized in that, The correlation between the hardness and density of the circular rock plunger sample is as follows: UCS = k × DEN + b Where UCS is the hardness of the rock circular plunger sample, DEN is the density of the rock circular plunger sample, and k and b are constants.

4. The method as described in claim 1, characterized in that, The correlation between hardness and porosity of rock samples of the corresponding type is corrected based on the hardness correction coefficient, including: the ideal hardness threshold includes the maximum ideal hardness threshold and the minimum ideal hardness threshold; Input the preset ideal density of each type of rock sample into the corresponding hardness-density correlation formula to obtain the ideal hardness threshold output for each type of rock sample. When the output hardness of any type of rock sample is less than the minimum ideal hardness threshold, or when the output hardness of any type of rock sample is greater than the maximum ideal hardness threshold, the correlation between hardness and porosity of the corresponding type of rock sample is corrected based on the correction coefficient.

5. The method as described in claim 4, characterized in that, Based on the comparison results, the output density of each type of rock sample, and the preset ideal density and hardness threshold, the hardness correction coefficient is calculated, including: When the output hardness of any type of rock sample is less than the minimum ideal hardness threshold, the correction coefficient is: a = 1 + (UCS min - UCS ave ) / UCS min When the output hardness of any type of rock sample exceeds the maximum ideal hardness threshold, the correction coefficient is: a = 1 - (UCS max - UCS ave ) / UCS max where a is a correction factor, UCS min is a minimum ideal hardness threshold, UCS max is a maximum ideal hardness threshold, UCS ave is the output hardness of the rock sample.

6. The method as described in claim 1, characterized in that, The correlation between hardness and porosity for each type of rock sample is as follows: POR = a x ln(UCS ave ) + β wherein POR is the porosity of the rock sample, UCS ave is the unconfined compressive strength of the rock sample, and a, β are regression coefficients.

7. A porosity detection device based on rock hardness, characterized in that, include: The module for determining the relationship between hardness and density is used to collect circular rock plunger samples of different types, measure the hardness of each type of circular rock plunger sample, and determine the correlation between the hardness and density of each type of circular rock plunger sample. The hardness correction coefficient calculation module is used to input the preset ideal density of each type of rock sample into the correlation formula between hardness and density of the corresponding type to obtain the output ideal hardness of each type of rock sample; compare the hardness of the rock sample to be tested with the ideal hardness threshold of the corresponding type to obtain the comparison result; and calculate the hardness correction coefficient based on the comparison result. The cross plot creation module is used to create a cross plot of the hardness and porosity of each type of rock circular plunger sample based on the measured hardness and corresponding porosity. The module for determining the relationship between hardness and porosity is used to determine the correlation between hardness and porosity for each type of rock sample based on the cross plot. The correlation between hardness and porosity of rock samples of the corresponding type is corrected based on the hardness correction coefficient. The porosity determination module for the rock sample under test is used to input the hardness of the rock sample under test into the corrected correlation formula between the hardness and porosity of the corresponding type of rock sample to obtain the porosity of the rock sample under test.

8. The apparatus as claimed in claim 7, characterized in that, The module for determining the relationship between hardness and density is specifically used for: The hardness of each type of rock circular plunger sample was measured multiple times to obtain the hardness measurement value of the rock circular plunger sample for each measurement. The average hardness of each type of rock circular plunger sample was calculated using the tail-cutting mean method based on the measured hardness values ​​of the rock circular plunger samples. Determine the correlation between hardness and density for each type of rock circular plunger sample, including: Based on the average hardness and known density of the circular rock plunger samples of each type, the correlation formula between the hardness and density of the circular rock plunger samples of each type is determined.

9. The apparatus as claimed in claim 7, characterized in that, The correlation between the hardness and density of the circular rock plunger sample is as follows: UCS = k × DEN + b Where UCS is the hardness of the rock circular plunger sample, DEN is the density of the rock circular plunger sample, and k and b are constants.

10. The apparatus as claimed in claim 7, characterized in that, The hardness correction coefficient calculation module is specifically used for: The correlation between hardness and porosity of rock samples of the corresponding type is corrected based on the hardness correction coefficient. The ideal hardness threshold includes the maximum ideal hardness threshold and the minimum ideal hardness threshold. Input the preset ideal density of each type of rock sample into the corresponding hardness-density correlation formula to obtain the ideal hardness threshold output for each type of rock sample. When the output hardness of any type of rock sample is less than the minimum ideal hardness threshold, or when the output hardness of any type of rock sample is greater than the maximum ideal hardness threshold, the correlation between hardness and porosity of the corresponding type of rock sample is corrected based on the correction coefficient.

11. The apparatus as claimed in claim 10, characterized in that, The hardness correction coefficient calculation module is specifically used for: When the output hardness of any type of rock sample is less than the minimum ideal hardness threshold, the correction coefficient is: a = 1 + (UCS min - UCS ave ) / UCS min When the output hardness of any type of rock sample exceeds the maximum ideal hardness threshold, the correction coefficient is: a = 1 - (UCS max - UCS ave ) / UCS max where a is a correction factor, UCS min is a minimum ideal hardness threshold, UCS max is a maximum ideal hardness threshold, UCS ave is the output hardness of the rock sample.

12. The apparatus as claimed in claim 7, characterized in that, The correlation between hardness and porosity for each type of rock sample is as follows: POR = a x ln(UCS) + β ave + β wherein POR is the porosity of the rock sample, UCS ave is the unconfined compressive strength of the rock sample, and a, β are regression coefficients.

13. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method of any one of claims 1 to 6.

14. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method of any one of claims 1 to 6.

15. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the method of any one of claims 1 to 6.

Images