Method, device and apparatus for determining chloroform bitumen "a" content of shale

Abstract

The embodiment of the present application provides a method, device and equipment for determining the content of chloroform bitumen A of shale, which comprises the following steps: firstly, collecting the T1-T2 spectrum of the target shale by using a T1-T2 two-dimensional nuclear magnetic resonance device; then, calculating the signal area percentage for representing the content of chloroform bitumen A based on the T1-T2 spectrum of the target shale; finally, determining the content of chloroform bitumen A of the target shale according to the signal area percentage and a pre-established relationship model, wherein the relationship model is used to represent the mapping relationship between the signal area percentage and the content of chloroform bitumen A. Without crushing the target shale, the target shale will not be physically irreversibly damaged; only the T1-T2 spectrum of the target shale needs to be collected, the measurement cycle is short, and the content of chloroform bitumen A of shale is quickly, economically and non-destructively determined.

Description

Technical Field

[0001] This invention relates to the field of petroleum engineering technology, specifically to a method, apparatus, and equipment for determining the "A" content of chloroform bitumen in shale based on T1-T2 two-dimensional nuclear magnetic resonance. Background Technology

[0002] Chloroform bitumen "A" refers to the content of soluble organic matter that is soluble in chloroform, and is an important indicator of organic matter abundance. The chloroform bitumen "A" content in shale has important guiding significance for oil and gas exploration and development; therefore, accurately determining the chloroform bitumen "A" content in shale is of great value.

[0003] Current techniques primarily rely on geochemical experiments to determine the chloroform bitumen "A" content in shale. The specific steps include: first, crushing the shale core sample; then, extracting and naturally drying it; finally, calculating the chloroform bitumen extract content per unit of rock, which is the chloroform bitumen "A" content. While this method can accurately determine the chloroform bitumen "A" content in shale, it still has several drawbacks: first, it is time-consuming, requiring approximately 3 to 5 days; second, it is costly, not only due to high personnel costs but also the high cost of the required equipment; third, it is not continuous; and fourth, it causes irreversible damage to the shale core, making it inconvenient for conducting other complementary experiments.

[0004] In conclusion, there is an urgent need for a rapid and economical method to determine the "A" content of shale chloroform bitumen. Summary of the Invention

[0005] This invention provides a method, apparatus, and equipment for determining the "A" content of shale chloroform bitumen based on T1-T2 two-dimensional nuclear magnetic resonance, in order to overcome the shortcomings of the existing technology that uses geochemical experiments to determine the "A" content of shale chloroform bitumen.

[0006] In a first aspect, embodiments of the present invention provide a method for determining the "A" content of shale chloroform bitumen, comprising:

[0007] Obtain the target shale to be tested;

[0008] The T1-T2 spectra of the target shale were acquired using a T1-T2 two-dimensional nuclear magnetic resonance (NMR) instrument.

[0009] The percentage of signal area used to characterize the "A" content of chloroform bitumen was calculated based on the T1-T2 spectrum of the target shale.

[0010] The chloroform bitumen "A" content of the target shale is determined based on the percentage of signal area and a pre-established relational model, which represents the mapping relationship between the percentage of signal area and the chloroform bitumen "A" content.

[0011] In one embodiment, a T1-T2 two-dimensional nuclear magnetic resonance (NMR) device is used to acquire the T1-T2 spectrum of the target shale according to the following parameters:

[0012] The magnetic field strength is (20±5)MHz, the probe aperture is not less than 15mm, the pulse sequence is the inversion recovery method, the echo interval is 0.06ms, the waiting time is 10ms, and the inversion method is the regularization method.

[0013] In one embodiment, calculating the percentage of signal area used to characterize the "A" content of chloroform bitumen based on the T1-T2 spectrum of the target shale includes:

[0014] Calculate the area of ​​the first signal within the first region on the T1-T2 spectrum. The first region is the region on the T1-T2 spectrum where 15ms≤T1≤500ms and 1≤T1 / T2≤40.

[0015] Calculate the area of ​​the second signal within the second region on the T1-T2 spectrum. The second region is the area on the T1-T2 spectrum where 15ms≤T1≤500ms and 30≤T1 / T2≤600.

[0016] Calculate the area of ​​the third signal in the third region of the T1-T2 spectrum. The third region is the region in the T1-T2 spectrum where 0.1ms≤T2≤2ms and 1≤T1 / T2≤3.

[0017] Calculate the total effective area of ​​the T1-T2 spectrum;

[0018] The percentage of the sum of the first signal area, the second signal area, and the third signal area to the total effective area is determined as the percentage of signal area used to characterize the content of chloroform bitumen "A".

[0019] In one embodiment, the method further includes: identifying the pore fluid type and occurrence state of the shale reservoir based on the T1-T2 spectrum of the target shale.

[0020] In one embodiment, before acquiring the target shale to be detected, the method further includes establishing a relational model according to the following process:

[0021] Obtain a predetermined number of shale samples;

[0022] The T1-T2 spectra of each shale sample were acquired using a T1-T2 two-dimensional nuclear magnetic resonance device;

[0023] The percentage of signal area used to characterize the "A" content of chloroform bitumen for each shale sample was calculated based on the T1-T2 spectrum of each shale sample.

[0024] The chloroform bitumen "A" content of each shale sample was measured using geochemical experiments;

[0025] Statistical analysis was performed on the signal area percentage and chloroform bitumen "A" content of a predetermined number of shale samples to establish a relationship model representing the mapping relationship between the signal area percentage and the chloroform bitumen "A" content.

[0026] In one embodiment, the relational model is a linear model or an exponential model.

[0027] In one embodiment, when the relational model is a linear model, the relational model is as follows:

[0028] C A =0.0125×m-0.4304;

[0029] Among them, C A The value of chloroform asphalt “A” is indicated, and m represents the percentage of signal area.

[0030] Secondly, embodiments of the present invention provide an apparatus for determining the "A" content of shale chloroform bitumen, comprising:

[0031] The acquisition module is used to acquire the target shale to be detected;

[0032] The acquisition module is used to acquire the T1-T2 spectrum of the target shale using a T1-T2 two-dimensional nuclear magnetic resonance device;

[0033] The calculation module is used to calculate the percentage of signal area used to characterize the "A" content of chloroform bitumen based on the T1-T2 spectrum of the target shale;

[0034] The processing module is used to determine the chloroform bitumen "A" content of the target shale based on the signal area percentage and a pre-established relational model, which represents the mapping relationship between the signal area percentage and the chloroform bitumen "A" content.

[0035] Thirdly, embodiments of the present invention provide an electronic device, comprising:

[0036] At least one processor and memory;

[0037] The memory stores the instructions that the computer executes;

[0038] At least one processor executes computer execution instructions stored in memory, causing the at least one processor to perform a method for determining the content of chloroform bitumen “A” in shale, as described in any of the first aspects.

[0039] Fourthly, embodiments of the present invention provide a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the method for determining the content of shale chloroform bitumen "A" as described in any of the first aspects.

[0040] The method, apparatus, and equipment for determining the chloroform bitumen "A" content in shale provided in this invention first employ a T1-T2 two-dimensional nuclear magnetic resonance (NMR) instrument to acquire the T1-T2 spectrum of the target shale. Then, based on the T1-T2 spectrum of the target shale, the percentage of signal area used to characterize the chloroform bitumen "A" content is calculated. Finally, the chloroform bitumen "A" content of the target shale is determined according to the percentage of signal area and a pre-established relational model, wherein the relational model represents the mapping relationship between the percentage of signal area and the chloroform bitumen "A" content. This method eliminates the need to crush the target shale, avoiding any irreversible physical damage; it only requires acquiring the T1-T2 spectrum of the target shale, resulting in a short measurement cycle and enabling rapid, economical, and non-destructive determination of the chloroform bitumen "A" content in shale. Attached Figure Description

[0041] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0042] Figure 1 A flowchart illustrating a method for determining the "A" content of shale chloroform bitumen according to an embodiment of the present invention;

[0043] Figure 2 A schematic diagram of the T1-T2 spectrum of shale obtained using existing methods;

[0044] Figure 3 A schematic diagram of the T1-T2 spectrum of shale obtained by the method of the present invention according to an embodiment of the present invention;

[0045] Figure 4 A flowchart illustrating a method for determining the "A" content of shale chloroform bitumen according to another embodiment of the present invention;

[0046] Figure 5 A flowchart for establishing a relationship model is provided in one embodiment of the present invention;

[0047] Figure 6 This is a schematic diagram showing the intersection of signal area percentage and chloroform pitch "A" content according to an embodiment of the present invention;

[0048] Figure 7 A schematic diagram of the T1-T2 spectrum of a target shale provided in an embodiment of the present invention;

[0049] Figure 8 A schematic diagram of the structure of an apparatus for determining the "A" content of shale chloroform bitumen according to an embodiment of the present invention;

[0050] Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0051] The accompanying drawings have illustrated specific embodiments of the invention, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the invention in any way, but rather to illustrate the concept of the invention to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0052] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of this application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to this application are not shown or described in the specification. This is to avoid obscuring the core parts of this application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0053] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.

[0054] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages).

[0055] Example 1

[0056] Figure 1 A flowchart illustrating a method for determining the "A" content of shale chloroform bitumen according to an embodiment of the present invention.

[0057] like Figure 1 As shown, the method for determining the "A" content of shale chloroform bitumen provided in this embodiment may include:

[0058] S101. Obtain the target shale to be detected.

[0059] Shale typically contains liquids and / or gases, making its state not very stable. Therefore, in order to ensure the accuracy of the measurement results, fresh shale can be obtained as the target shale to be tested in this embodiment.

[0060] S102. The T1-T2 spectrum of the target shale was acquired using a T1-T2 two-dimensional nuclear magnetic resonance device.

[0061] When acquiring the T1-T2 spectrum of the target shale using a T1-T2 two-dimensional nuclear magnetic resonance (NMR) device, it is not necessary to crush the target shale, thus avoiding irreversible physical damage. Here, T1 represents the longitudinal relaxation time, and T2 represents the transverse relaxation time. To improve the accuracy of the chloroform bitumen "A" content in the shale, this embodiment can adjust the parameters of the T1-T2 NMR device to ensure that the obtained T1-T2 spectrum of the target shale has a high signal-to-noise ratio (SNR) and at least three signal peaks. For example, a SNR threshold can be set to ensure that the SNR of the target shale's T1-T2 spectrum exceeds the threshold.

[0062] S103. Calculate the percentage of signal area used to characterize the "A" content of chloroform bitumen based on the T1-T2 spectrum of the target shale.

[0063] The signals on the T1-T2 spectrum can reflect the content of various substances in the target shale to a certain extent. In this embodiment, the sum of the areas of all signals on the T1-T2 spectrum used to characterize the content of chloroform bitumen "A" can be calculated, and the percentage of this sum to the total effective area of ​​the T1-T2 spectrum (excluding the signal area of ​​noise) is determined as the percentage of the signal area used to characterize the content of chloroform bitumen "A".

[0064] S104. Determine the chloroform bitumen “A” content of the target shale based on the signal area percentage and the pre-established relational model. The relational model is used to represent the mapping relationship between the signal area percentage and the chloroform bitumen “A” content.

[0065] Before testing the target shale, a mapping model can be pre-established to represent the relationship between the percentage of signal area and the content of chloroform bitumen "A". For example, a large number of fresh shale samples can be collected. For each shale sample, T1-T2 two-dimensional nuclear magnetic resonance analysis is first used to determine the corresponding percentage of signal area used to characterize the chloroform bitumen "A" content. Then, geochemical experiments are used to measure the corresponding chloroform bitumen "A" content. Finally, machine learning methods are used to learn the mapping relationship between the percentage of signal area and the chloroform bitumen "A" content, establishing the relationship model. It should be noted that to improve the accuracy of the chloroform bitumen "A" content in shale, all parameters used in the target shale testing process must be consistent with the parameters used when establishing the relationship model. For example, the parameters used when collecting T1-T2 spectra and the parameters used when calculating the percentage of signal area used to characterize the chloroform bitumen "A" content, etc.

[0066] After obtaining the percentage of signal area in the T1-T2 spectrum of the target shale used to characterize the chloroform bitumen "A" content, it is only necessary to input it into a pre-established relational model to determine the chloroform bitumen "A" content of the target shale.

[0067] The method for determining the chloroform bitumen "A" content in shale provided in this embodiment first uses a T1-T2 two-dimensional nuclear magnetic resonance (NMR) instrument to acquire the T1-T2 spectrum of the target shale; then, based on the T1-T2 spectrum of the target shale, the percentage of signal area used to characterize the chloroform bitumen "A" content is calculated; finally, the chloroform bitumen "A" content of the target shale is determined according to the percentage of signal area and a pre-established relational model, wherein the relational model is used to represent the mapping relationship between the percentage of signal area and the chloroform bitumen "A" content. This method eliminates the need to crush the target shale, thus avoiding any irreversible physical damage; it only requires acquiring the T1-T2 spectrum of the target shale, has a short measurement cycle, and achieves a rapid, economical, and non-destructive determination of the chloroform bitumen "A" content in shale.

[0068] Example 2

[0069] During the acquisition of T1-T2 spectra using a T1-T2 two-dimensional nuclear magnetic resonance (NMR) device, the T1-T2 spectra obtained with different parameters exhibit uncertainties. Please refer to [reference needed]. Figure 2 , Figure 2 This is a schematic diagram of the T1-T2 spectrum of shale obtained using existing methods. Figure 2 The magnetic field frequency used in [a] was 21.36 MHz. The obtained T1-T2 spectrum showed peak overlap, and the hydrocarbon signals included kerogen, adsorbed oil, and mobile oil. Figure 2 The magnetic field frequency used in [b] was 12 MHz. The hydrocarbon signals in the obtained T1-T2 spectrum included kerogen and mobile oil. The position of the kerogen signal was related to... Figure 2 Medium [a] is equivalent. Figure 2 The magnetic field frequency used in [c] was 23.7 MHz. The hydrocarbon signals in the obtained T1-T2 spectra included kerogen and methane in the porous medium. The long axis direction of the kerogen signal was parallel to... Figure 2 [a] and Figure 2 There are differences in [b]. Figure 2 The numerical meanings shown in the signal peaks are as follows: 1: Kerogen; 2: Adsorbed oil; 3: Free oil; 4: Structural water; 5: Free water; 6: Adsorbed water; 7: Organic matter; 8: Methane; 9: Clay structural water; 10: Pore water; 11: Crack water; 12: Kerogen; 13: Hydroxyl groups; 14: Methane in porous media; 15: Water (clay water, intergranular water). Figure 2 It is evident that the distribution of signal peaks in the T1-T2 spectrum obtained by existing methods using different parameters is chaotic and not conducive to effective analysis.

[0070] Therefore, based on the above embodiments, in order to further improve the standardization of the process for determining the "A" content of shale chloroform bitumen, improve the accuracy of the "A" content of shale chloroform bitumen, and avoid human error in parameter selection during the process, the method for determining the "A" content of shale chloroform bitumen provided in this embodiment uses a T1-T2 two-dimensional nuclear magnetic resonance device to acquire the T1-T2 spectrum of the target shale according to the following parameters: magnetic field strength of (20±5)MHz, probe aperture of not less than 15mm, pulse sequence of inversion recovery method, echo interval of 0.06ms, waiting time of 10ms, and inversion method of regularization method. Figure 3 This is a schematic diagram of the T1-T2 spectrum of shale obtained using the method of the present invention, provided as an embodiment of the present invention. (See diagram below.) Figure 3 As shown, the shale T1-T2 spectrum obtained by the method of the present invention has a high signal-to-noise ratio, a relatively regular distribution of signal peaks, and four signal peaks. Each signal peak can be clearly separated by adjusting the amplitude contour lines.

[0071] After obtaining a T1-T2 spectrum with high signal-to-noise ratio, regular signal peak distribution, and clear separation according to the above acquisition parameters, the percentage of signal area used to characterize the chloroform bitumen "A" content based on the T1-T2 spectrum of the target shale can specifically include:

[0072] Calculate the first signal area A1 in the first region of the T1-T2 spectrum. The first region is the region in the T1-T2 spectrum where 15ms≤T1≤500ms and 1≤T1 / T2≤40.

[0073] Calculate the area A2 of the second signal within the second region on the T1-T2 spectrum. The second region is the region on the T1-T2 spectrum where 15ms≤T1≤500ms and 30≤T1 / T2≤600.

[0074] Calculate the area A3 of the third signal within the third region on the T1-T2 spectrum. The third region is the region on the T1-T2 spectrum where 0.1ms≤T2≤2ms and 1≤T1 / T2≤3.

[0075] It should be noted that if the signals in each region cannot be separated from the signals in other regions, the boundary values ​​of the regions can be slightly adjusted. Specifically, this can be done by adjusting the contour lines of the T1-T2 two-dimensional spectrum or by finding the lowest value between signal peaks in the spectrum data table as the dividing point. In other words, the size of the first, second, and third regions can be adjusted by adjusting the contour lines of the T1-T2 spectrum to separate the signals in each region; alternatively, the size of the first, second, and third regions can be adjusted based on the lowest value between the signal peaks in the T1-T2 spectrum as the dividing point to separate the signals in each region.

[0076] Calculate the total effective area ∑ of the T1-T2 spectrum.i A i A i ∑ represents the signal area of ​​the i-th valid signal on the T1-T2 spectrum. i This indicates that the effective signal area across the T1-T2 spectrum is summed. It should be noted that the total effective area does not include the area of ​​the noise signal.

[0077] The percentage of the sum of the first, second, and third signal areas relative to the total effective area is determined as the percentage of the signal area used to characterize the chloroform bitumen "A" content. Specifically, the percentage m of the signal area used to characterize the chloroform bitumen "A" content can be determined according to the following expression:

[0078] m=(A1+A2+A3) / ∑ i A i ×100%.

[0079] The method for determining the chloroform bitumen "A" content in shale provided in this embodiment, based on the above embodiment, further specifies the parameters used when collecting the T1-T2 spectrum of the target shale, and further clarifies the specific method for calculating the percentage of signal area used to characterize the chloroform bitumen "A" content based on the T1-T2 spectrum of the target shale. This not only improves the standardization of the process for determining the chloroform bitumen "A" content in shale, but also effectively improves the accuracy of the chloroform bitumen "A" content in shale.

[0080] Example 3

[0081] In the study of shale oil and shale gas, T1-T2 two-dimensional nuclear magnetic resonance technology is often used to determine the pore fluid type and occurrence state of shale reservoirs. Figure 4 A flowchart illustrating a method for determining the "A" content of shale chloroform bitumen according to another embodiment of the present invention is shown below. Figure 4 As shown, in order to improve the efficiency of determining the "A" content of shale chloroform bitumen, the method provided in this embodiment may include:

[0082] S401. Obtain the target shale to be detected.

[0083] S402. The T1-T2 spectrum of the target shale was acquired using a T1-T2 two-dimensional nuclear magnetic resonance device.

[0084] S403. Identify the pore fluid type and occurrence state of shale reservoirs based on the T1-T2 spectrum of the target shale.

[0085] S404. Calculate the percentage of signal area used to characterize the "A" content of chloroform bitumen based on the T1-T2 spectrum of the target shale;

[0086] S405. Determine the chloroform bitumen “A” content of the target shale based on the signal area percentage and the pre-established relational model. The relational model is used to represent the mapping relationship between the signal area percentage and the chloroform bitumen “A” content.

[0087] It should be noted that the execution order of steps S403 and S404 is not limited in this embodiment. When identifying the pore fluid type and occurrence state of shale reservoirs based on the T1-T2 spectrum of the target shale, methods in the prior art can be used, and this embodiment does not limit the specific implementation method. The specific implementation methods of other steps can refer to the implementation in Embodiment 1, and will not be repeated here.

[0088] The method for determining the chloroform bitumen "A" content in shale provided in this embodiment, after obtaining the T1-T2 spectrum of the target shale, not only identifies the pore fluid type and occurrence state of the shale reservoir based on the T1-T2 spectrum, but also determines the chloroform bitumen "A" content of the target shale based on the T1-T2 spectrum. This method can determine the chloroform bitumen "A" content of the target shale at a very low cost while identifying the pore fluid type and occurrence state of the target shale reservoir, thus achieving rapid and economical determination of the chloroform bitumen "A" content in shale and improving the efficiency of determining the chloroform bitumen "A" content in shale.

[0089] Example 4

[0090] Understandably, a relationship model needs to be established beforehand to detect the target shale. Please refer to [reference needed]. Figure 5 In the method for determining the "A" content of chloroform bitumen in shale provided in this embodiment, the process of establishing a relational model before obtaining the target shale to be tested may include:

[0091] S501. Obtain a preset number of shale samples.

[0092] Collect a series of fresh and well-preserved shale samples. Understandably, the more shale samples collected, the higher the accuracy of the resulting relational model, but also the higher the computational complexity. Therefore, the preset number can be determined comprehensively based on the accuracy requirements of the relational model and the computational complexity requirements.

[0093] S502. The T1-T2 spectrum of each shale sample was acquired using a T1-T2 two-dimensional nuclear magnetic resonance device.

[0094] A T1-T2 two-dimensional nuclear magnetic resonance analyzer was used, with a magnetic field strength of 20±5MHz, a probe diameter of not less than 15mm, an inversion recovery method (IR-CPMG) pulse sequence, an echo interval (TE) of 0.06ms, a waiting time (TW) of 10ms, and a regularization method for inversion. T1-T2 spectra were acquired for each shale sample. The acquired T1-T2 spectra had a high signal-to-noise ratio and at least 3 signal peaks.

[0095] S503. Calculate the percentage of signal area corresponding to each shale sample used to characterize the "A" content of chloroform bitumen based on the T1-T2 spectrum of each shale sample.

[0096] For each shale sample, calculate or read the signal area (A1) within the interval 15ms ≤ T1 ≤ 500ms and 1 ≤ T1 / T2 ≤ 40, the signal area (A2) within the interval 15ms ≤ T1 ≤ 500ms and 30 ≤ T1 / T2 ≤ 600, and the signal area (A3) within the interval 0.1ms ≤ T2 ≤ 2ms and 1 ≤ T1 / T2 ≤ 3. Note: If the signal in this region cannot be distinguished from the signal in other regions, the boundary value can be slightly adjusted. The adjustment method is to adjust the contour lines of the T1-T2 two-dimensional spectrum or find the lowest value between the signal peaks in the spectrum data table as the dividing point.

[0097] Then calculate or read the total effective area (∑) of the T1-T2 spectrum. i A i The effective area excludes noise signals. Finally, calculate the areas of A1, A2, and A3 and their percentage of the total effective area (∑). i A i The percentage of ) is the signal area m used to characterize the content of chloroform bitumen "A":

[0098] m=(A1+A2+A3) / ∑ i A i ×100%.

[0099] S504. The chloroform bitumen “A” content of each shale sample was measured using geochemical experiments.

[0100] In order to obtain accurate values ​​of chloroform bitumen "A" content in shale samples, in this embodiment, after performing T1-T2 two-dimensional nuclear magnetic resonance analysis on the shale samples, geochemical experiments were used to measure the chloroform bitumen "A" content of each shale sample.

[0101] S505. Statistical analysis is performed on the signal area percentage and chloroform bitumen “A” content of a preset number of shale samples to establish a relationship model to represent the mapping relationship between the signal area percentage and the chloroform bitumen “A” content.

[0102] Through statistical analysis, a relationship model between m and the "A" content of chloroform bitumen was established. The relationship model can be either a linear model or an exponential model.

[0103] The following example, using 11 shale samples, illustrates the process of establishing the relational model. Please refer to [link / reference]. Figure 6 , Figure 6 The diagram shows a cross-plot of the signal area percentage and the chloroform bitumen "A" content of these 11 shale samples. A linear model was used to fit the data, showing a high correlation (correlation coefficient as high as 0.89). Therefore, a linear model was adopted for fitting. The resulting relationship model is as follows:

[0104] C A =0.0125×m-0.4304;

[0105] Among them, C A The value of chloroform asphalt “A” is indicated, and m represents the percentage of signal area.

[0106] To further verify the accuracy of the relational model provided in this embodiment, pressure-maintaining drilling and core sampling were performed on the target section of shale oil well X, and the core samples were frozen with liquid nitrogen. One core sample was taken and its T1-T2 spectrum was measured under the following parameters: resonant frequency of 19MHz, probe coil diameter of 25mm, pullback interval (TE) of 0.06ms, and waiting time (TW) of 10ms. Figure 7 . Figure 7 There are four signal peaks. The curve above the T1-T2 spectrum is the projection of the T1-T2 spectrum onto the T2 direction. The value of each point on the curve is the sum of the values ​​at points on the straight line perpendicular to the T2 axis of the T1-T2 spectrum. The curve to the right of the T1-T2 spectrum is the projection of the T1-T2 spectrum onto the T1 direction. The value of each point on the curve is the sum of the values ​​at points on the straight line perpendicular to the T1 axis of the T1-T2 spectrum. According to... Figure 7 The T1-T2 spectrum shown yielded a calculated m of 49.06. Based on the relational model, the chloroform bitumen "A" content was calculated to be 0.182 g. Subsequently, geochemical experiments were conducted on the core sample, and the measured chloroform bitumen "A" content was 0.216 g with an absolute error of 0.034, indicating a small error and reliable results.

[0107] The method for determining the "A" content of chloroform bitumen in shale provided in this embodiment, based on any of the above embodiments, further elaborates in detail the process of establishing a relational model before obtaining the target shale to be tested. A series of fresh and well-preserved shale samples were collected, and T1-T2 two-dimensional nuclear magnetic resonance (NMR) analysis and chloroform bitumen "A" content analysis were performed on the same sample. The magnetic field strength of the T1-T2 two-dimensional NMR analyzer was 20±5 MHz, the probe diameter was not less than 15 mm, the pulse sequence was inversion recovery method (IR-CPMG), the echo interval (TE) was 0.06 ms, the waiting time (TW) was 10 ms, and the inversion method was regularization method. The measured T1-T2 spectrum had a high signal-to-noise ratio and no less than 3 signal peaks. The percentage of signal area m characterizing the chloroform bitumen "A" content was calculated based on the two-dimensional NMR T1-T2 spectrum. Through statistical analysis, a relationship model between m and the chloroform bitumen "A" content was established. Based on m of the target sample's T1-T2 spectrum and the established relationship model, the chloroform bitumen "A" content of the target sample was calculated. This method enables rapid, non-destructive, and highly accurate quantitative calculation of the "A" content in chloroform bitumen by acquiring high-quality T1-T2 spectra, filling the gap in evaluating the "A" content of chloroform bitumen through T1-T2 spectra. It is simple to operate, highly accurate, and has a wide range of applications and promising prospects.

[0108] Example 5

[0109] Figure 8 This is a schematic diagram of a device for determining the "A" content of shale chloroform bitumen according to an embodiment of the present invention. Figure 8 As shown, the device 80 for determining the "A" content of shale chloroform bitumen provided in this embodiment may include: an acquisition module 801, a collection module 802, a calculation module 803, and a processing module 804.

[0110] Acquisition module 801 is used to acquire the target shale to be detected;

[0111] The acquisition module 802 is used to acquire the T1-T2 spectrum of the target shale using a T1-T2 two-dimensional nuclear magnetic resonance device;

[0112] Calculation module 803 is used to calculate the percentage of signal area used to characterize the content of chloroform bitumen “A” based on the T1-T2 spectrum of the target shale;

[0113] The processing module 804 is used to determine the chloroform bitumen "A" content of the target shale based on the signal area percentage and a pre-established relational model. The relational model is used to represent the mapping relationship between the signal area percentage and the chloroform bitumen "A" content.

[0114] The apparatus of this embodiment can be used to perform Figure 1The technical solutions of the method embodiments shown are similar in principle and in effect, and will not be described again here.

[0115] In one embodiment, the acquisition module 802 is used to acquire the T1-T2 spectrum of the target shale using a T1-T2 two-dimensional nuclear magnetic resonance device according to the following parameters:

[0116] The magnetic field strength is (20±5)MHz, the probe aperture is not less than 15mm, the pulse sequence is the inversion recovery method, the echo interval is 0.06ms, the waiting time is 10ms, and the inversion method is the regularization method.

[0117] In one embodiment, the calculation module 803 is used to calculate the percentage of signal area used to characterize the chloroform bitumen "A" content based on the T1-T2 spectrum of the target shale. Specifically, this may include:

[0118] Calculate the area of ​​the first signal within the first region on the T1-T2 spectrum. The first region is the region on the T1-T2 spectrum where 15ms≤T1≤500ms and 1≤T1 / T2≤40.

[0119] Calculate the area of ​​the second signal within the second region on the T1-T2 spectrum. The second region is the area on the T1-T2 spectrum where 15ms≤T1≤500ms and 30≤T1 / T2≤600.

[0120] Calculate the area of ​​the third signal in the third region of the T1-T2 spectrum. The third region is the region in the T1-T2 spectrum where 0.1ms≤T2≤2ms and 1≤T1 / T2≤3.

[0121] Calculate the total effective area of ​​the T1-T2 spectrum;

[0122] The percentage of the sum of the first signal area, the second signal area, and the third signal area to the total effective area is determined as the percentage of signal area used to characterize the content of chloroform bitumen "A".

[0123] In one embodiment, the processing module 804 is further used to identify the pore fluid type and occurrence state of the shale reservoir based on the T1-T2 spectrum of the target shale.

[0124] In one embodiment, the apparatus 80 for determining the chloroform bitumen "A" content of shale may further include a statistical analysis module (not shown in the figure) for establishing a relational model according to the following process before acquiring the target shale to be tested:

[0125] Obtain a predetermined number of shale samples;

[0126] The T1-T2 spectra of each shale sample were acquired using a T1-T2 two-dimensional nuclear magnetic resonance device;

[0127] The percentage of signal area used to characterize the "A" content of chloroform bitumen for each shale sample was calculated based on the T1-T2 spectrum of each shale sample.

[0128] The chloroform bitumen "A" content of each shale sample was measured using geochemical experiments;

[0129] Statistical analysis was performed on the signal area percentage and chloroform bitumen "A" content of a predetermined number of shale samples to establish a relationship model representing the mapping relationship between the signal area percentage and the chloroform bitumen "A" content.

[0130] In one embodiment, the relational model is a linear model or an exponential model.

[0131] In one embodiment, when the relational model is a linear model, the relational model is as follows:

[0132] C A =0.0125×m-0.4304;

[0133] Among them, C A The value of chloroform asphalt “A” is indicated, and m represents the percentage of signal area.

[0134] Example 6

[0135] This invention also provides an electronic device, please refer to [link to relevant documentation]. Figure 9 As shown, the embodiments of the present invention are only used as examples. Figure 9 The examples are provided for illustration only and do not imply that the invention is limited to these examples. Figure 9 This is a schematic diagram of the structure of an electronic device provided according to an embodiment of the present invention. Figure 9 As shown, the electronic device 90 provided in this embodiment may include: a memory 901, a processor 902, and a bus 903. The bus 903 is used to connect the various components.

[0136] The memory 901 stores a computer program, which, when executed by the processor 902, can implement the technical solutions of any of the above method embodiments.

[0137] The memory 901 and processor 902 are electrically connected directly or indirectly to enable data transmission or interaction. For example, these components can be electrically connected to each other via one or more communication buses or signal lines, such as bus 903. The memory 901 stores a computer program that implements a method for determining the content of chloroform bitumen "A" in shale, including at least one software function module that can be stored in the memory 901 in the form of software or firmware. The processor 902 executes various functional applications and data processing by running the software program and modules stored in the memory 901.

[0138] The memory 901 can be, but is not limited to, Random Access Memory (RAM), Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), etc. The memory 901 stores programs, and the processor 902 executes the programs after receiving execution instructions. Furthermore, the software programs and modules within the memory 901 may also include an operating system, which may include various software components and / or drivers for managing system tasks (such as memory management, storage device control, power management, etc.) and can communicate with various hardware or software components to provide an operating environment for other software components.

[0139] Processor 902 can be an integrated circuit chip with signal processing capabilities. The aforementioned processor 902 can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. The general-purpose processor can be a microprocessor or any conventional processor. It is understood that... Figure 9 The structure shown is for illustrative purposes only and may include more... Figure 9 The more or fewer components shown, or having the same Figure 9 The different configurations shown. Figure 9 The components shown can be implemented in hardware and / or software.

[0140] This invention also provides a computer-readable storage medium storing a computer program thereon, which is executed by a processor to implement the technical solutions of any of the above method embodiments.

[0141] The various embodiments in this disclosure are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0142] The scope of protection of this disclosure is not limited to the embodiments described above. Obviously, those skilled in the art can make various modifications and variations to this disclosure without departing from its scope and spirit. If such modifications and variations fall within the scope of the claims of this disclosure and their equivalents, then the intent of this disclosure also includes such modifications and variations.

Claims

1. A method for determining the "A" content of chloroform bitumen in shale, characterized in that, include: Obtain the target shale to be tested; The T1-T2 spectra of the target shale were acquired using a T1-T2 two-dimensional nuclear magnetic resonance (NMR) device with the following parameters: The magnetic field strength is (20±5) MHz, the probe aperture is not less than 15 mm, the pulse sequence is the inversion recovery method, the echo interval is 0.06 ms, the waiting time is 10 ms, and the inversion method is the regularization method. The percentage of signal area used to characterize the "A" content of chloroform bitumen was calculated based on the T1-T2 spectrum of the target shale. The chloroform bitumen "A" content of the target shale is determined based on the signal area percentage and a pre-established relational model, wherein the relational model is used to represent the mapping relationship between the signal area percentage and the chloroform bitumen "A" content. The percentage of signal area used to characterize the "A" content of chloroform bitumen, calculated based on the T1-T2 spectrum of the target shale, includes: Calculate the first signal area within the first region on the T1-T2 spectrum, where the first region is the region on the T1-T2 spectrum where 15ms ≤ T1 ≤ 500ms and 1 ≤ T1 / T2 ≤ 40; Calculate the second signal area within the second region on the T1-T2 spectrum, where the second region is the area on the T1-T2 spectrum where 15ms ≤ T1 ≤ 500ms and 30 ≤ T1 / T2 ≤ 600; Calculate the area of ​​the third signal within the third region on the T1-T2 spectrum, where the third region is the region on the T1-T2 spectrum where 0.1ms ≤ T2 ≤ 2ms and 1 ≤ T1 / T2 ≤ 3; Calculate the total effective area of ​​the T1-T2 spectrum; determine the percentage of the sum of the first signal area, the second signal area, and the third signal area to the total effective area as the percentage of the signal area used to characterize the chloroform bitumen "A" content; Before acquiring the target shale to be detected, establishing the relationship model includes: Obtain a predetermined number of shale samples; The T1-T2 spectra of each shale sample were acquired using a T1-T2 two-dimensional nuclear magnetic resonance device; The percentage of signal area used to characterize the "A" content of chloroform bitumen for each shale sample was calculated based on the T1-T2 spectrum of each shale sample. The chloroform bitumen "A" content of each shale sample was measured using geochemical experiments; Statistical analysis was performed on the signal area percentage and chloroform bitumen "A" content of the preset number of shale samples to establish a relationship model to represent the mapping relationship between the signal area percentage and the chloroform bitumen "A" content.

2. The method according to claim 1, characterized in that, The method further includes: identifying the pore fluid type and occurrence state of the shale reservoir based on the T1-T2 spectrum of the target shale.

3. The method according to claim 1, characterized in that, The relationship model is either a linear model or an exponential model.

4. The method according to claim 3, characterized in that, When the relational model is a linear model, the relational model is: in, This indicates the content of chloroform bitumen "A". This represents the percentage of the signal area.

5. An apparatus for determining the content of "A" in shale chloroform bitumen, characterized in that, include: The acquisition module is used to acquire the target shale to be detected; The acquisition module is used to acquire the T1-T2 spectrum of the target shale using a T1-T2 two-dimensional nuclear magnetic resonance device with the following parameters: magnetic field strength of (20±5)MHz, probe aperture of not less than 15mm, pulse sequence of inversion recovery method, echo interval of 0.06ms, waiting time of 10ms, and inversion method of regularization method. The calculation module is used to calculate the percentage of signal area used to characterize the content of chloroform bitumen "A" based on the T1-T2 spectrum of the target shale. Specifically, it includes: calculating the first signal area in a first region on the T1-T2 spectrum, wherein the first region is the region on the T1-T2 spectrum where 15ms ≤ T1 ≤ 500ms and 1 ≤ T1 / T2 ≤ 40. Calculate the second signal area within the second region on the T1-T2 spectrum, where the second region is the area on the T1-T2 spectrum where 15ms ≤ T1 ≤ 500ms and 30 ≤ T1 / T2 ≤ 600; Calculate the area of ​​the third signal within the third region on the T1-T2 spectrum, where the third region is the region on the T1-T2 spectrum where 0.1ms ≤ T2 ≤ 2ms and 1 ≤ T1 / T2 ≤ 3; Calculate the total effective area of ​​the T1-T2 spectrum; determine the percentage of the sum of the first signal area, the second signal area, and the third signal area to the total effective area as the percentage of the signal area used to characterize the chloroform bitumen "A" content; The processing module is used to determine the chloroform bitumen "A" content of the target shale based on the signal area percentage and a pre-established relationship model, wherein the relationship model is used to represent the mapping relationship between the signal area percentage and the chloroform bitumen "A" content. The statistical analysis module is used to establish a relational model before acquiring the target shale for testing, following the process described below: Obtain a predetermined number of shale samples; The T1-T2 spectra of each shale sample were acquired using a T1-T2 two-dimensional nuclear magnetic resonance device; The percentage of signal area used to characterize the "A" content of chloroform bitumen for each shale sample was calculated based on the T1-T2 spectrum of each shale sample. The chloroform bitumen "A" content of each shale sample was measured using geochemical experiments; Statistical analysis was performed on the signal area percentage and chloroform bitumen "A" content of the preset number of shale samples to establish a relationship model to represent the mapping relationship between the signal area percentage and the chloroform bitumen "A" content.

6. An electronic device, characterized in that, include: At least one processor and memory; The memory stores computer-executed instructions; The at least one processor executes computer execution instructions stored in the memory, causing the at least one processor to perform the method for determining the content of chloroform bitumen "A" in shale as described in any one of claims 1-4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method for determining the content of "A" in shale chloroform bitumen as described in any one of claims 1-4.

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