Labeling seam development section identification method and device, equipment and medium

Abstract

The invention relates to the technical field of shale reservoir logging evaluation, in particular to a lamellar fracture development section identification method and device, equipment and a medium, and the method comprises the steps: obtaining dipole transverse wave train data corresponding to each receiver obtained by acoustic logging in a research area, and calculating an amplitude time window; determining transverse wave amplitudes corresponding to all receivers according to the dipole transverse wave train in the amplitude calculation time window; determining a shear wave amplitude attenuation index corresponding to each receiver by taking a compact sandstone section on the shear wave amplitude as a baseline; assigning a corresponding non-shale section in the shear wave amplitude attenuation index as 0; and establishing a lamellar fracture classification standard, performing category division on the shear wave amplitude attenuation index according to the classification standard, and identifying a lamellar fracture development section of the shale section according to a category division result. And quantitative evaluation of the lamellar fracture development condition provides technical support for reservoir geological dessert optimization.

Description

Technical Field

[0001] This invention relates to the field of shale reservoir logging evaluation technology, and in particular to a method, device, equipment and medium for identifying shale fracture development sections. Background Technology

[0002] Shale, also known as foliated bedding, refers to the characteristic of argillaceous rocks splitting into thin plates or sheets parallel to their bedding planes, typically less than 1 cm thick. Shale is the solid body of shale, while foliation fractures are the gaps between two foliation sheets. Foliation fractures are open fractures, generally 1–200 μm wide, belonging to the micrometer-scale fractures. Foliation fractures in shale reservoirs are generally characterized by continuous, segmental development, significantly enhancing the reservoir's reservoir capacity and permeability.

[0003] Current technologies have been extensively studied for the identification and quantitative calculation of large-scale tectonic fractures, resulting in relatively mature technical methods. However, research on smaller-scale foliation fractures in shale and argillaceous formations is limited, and mature characterization and quantitative calculation methods have not yet been developed. Statistical analysis of marine shale reservoirs in the Longmaxi Formation by Ou Chenghua, Li Chaochun, and others revealed a positive correlation between foliation fractures and silica and organic carbon content in the Longmaxi Formation. They established a regression model for foliation fracture density in the Longmaxi Formation using a regression approach. However, this regression method has significant limitations; it is applicable to a specific block but not to another block or stratigraphic level, thus lacking broad applicability. Summary of the Invention

[0004] This invention proposes a method, device, equipment, and medium for identifying foliation fracture development segments, in order to solve the problem that there is currently no mature and universal method for characterizing and quantitatively calculating small-scale foliation fractures, which makes it impossible to clearly understand the development of small-scale foliation fractures and effectively guide the tapping of remaining oil potential.

[0005] According to one aspect of the present invention, a method for identifying lamellar suture development segments is provided, characterized in that it includes:

[0006] Acquire dipole shear wave train data for each receiver obtained by acoustic logging in the study area and calculate the amplitude time window.

[0007] Based on the dipole shear wave train that is within the calculated amplitude time window, determine the shear wave amplitude corresponding to all receivers;

[0008] Using the dense sandstone section on the shear wave amplitude as the baseline, determine the shear wave amplitude attenuation index corresponding to each receiver;

[0009] The non-shale segment corresponding to the transverse wave amplitude attenuation index is assigned a value of 0;

[0010] Establish a classification standard for foliation fractures, classify the transverse wave amplitude attenuation index according to the classification standard, and identify the foliation fracture development sections of shale segments based on the classification results.

[0011] Preferably, before obtaining the calculation amplitude time window corresponding to each receiver, the method for determining the calculation amplitude time window includes:

[0012] Obtain the transverse wave arrival time for each receiver;

[0013] For each dipole shear wave train corresponding to each receiver, the amplitude calculation time window is determined with the arrival time of the shear wave corresponding to that receiver as the start time and the arrival time of the shear wave plus a predetermined time as the end time.

[0014] Preferably, the predetermined time is 600 μs.

[0015] Preferably, the method for determining the transverse wave arrival time before obtaining the transverse wave arrival time corresponding to each receiver includes:

[0016] Obtain the transverse wave time difference and the arrival time of the first receiver's transverse wave;

[0017] Based on the shear wave time difference and the shear wave arrival time of the first receiver, the shear wave arrival time of the other receivers is determined.

[0018] Preferably, the baseline is determined before using the dense sandstone segment on the shear wave amplitude as the baseline, and the method includes:

[0019] The baseline is determined at the point where the transverse wave amplitude reaches its maximum value.

[0020] Preferably, the method for identifying the non-shale segment before assigning a value of 0 to the corresponding non-shale segment in the shear wave amplitude attenuation index includes:

[0021] Acquire acoustic transit time and natural gamma logging curves;

[0022] Based on the sonic transit time and natural gamma logging curves, identify the shale section of the reservoir;

[0023] In the transverse wave amplitude attenuation index, the portion other than the portion corresponding to the shale segment is the non-shale segment.

[0024] Preferably, the method for identifying reservoir shale sections based on the sonic transit time and natural gamma logging curves includes:

[0025] The scale range of the sonic transit time logging curve and the natural gamma logging curve is adjusted to the predetermined scale range;

[0026] The natural gamma ray logging curve and the sonic transit time logging curve are superimposed. After superposition, the part corresponding to the right side of the sonic transit time logging curve of the natural gamma ray logging curve is determined to be the shale section.

[0027] Preferably, the predetermined scale range of the sonic transit time logging curve is 140-40 μS / ft;

[0028] The predetermined scale range of the natural gamma logging curve is 0-150 API.

[0029] Preferably, the method for determining the transverse wave amplitude corresponding to each receiver based on the dipole transverse wave train within the calculated amplitude time window includes:

[0030] The transverse wave amplitude corresponding to the receiver is determined using equation (1);

[0031]

[0032] Where: AMP i denoted as the transverse wave amplitude of the i-th receiver, in dB; M is the total number of sampling points within the time window; WAVE(i) is the amplitude of the i-th sampling point, in dB.

[0033] Preferably, the method for determining the shear wave amplitude attenuation index corresponding to all receivers, using the dense sandstone segment on the shear wave amplitude as a baseline, includes:

[0034] Based on the shear wave amplitude and the baseline, the shear wave amplitude attenuation of each receiver is determined using equation (2);

[0035]

[0036] In the formula: Anis i AMP is the shear wave amplitude attenuation exponent for the i-th receiver, %; i Let be the transverse wave amplitude of the i-th receiver, in dB; AMP ib Let be the baseline value of the i-th receiver, in dB;

[0037] The average value of the shear wave amplitude attenuation of all the receivers is obtained, which is the shear wave amplitude attenuation index corresponding to all the receivers.

[0038] Preferably, the method for establishing the classification criteria for page seams includes:

[0039] Core experiments were conducted on the target wells in the study area to obtain data on the range of core foliation density.

[0040] Based on the data on the density range of the page seams, the data is divided into several level ranges using the principle of equal division;

[0041] Plot the relationship between the core foliation density and the shear wave amplitude attenuation index;

[0042] Based on the relationship curve, determine the range of transverse wave amplitude attenuation index levels corresponding to each of the page seam density levels;

[0043] After all the shear wave amplitude attenuation index levels are sorted in descending order, they correspond to several ascending classification levels, which are the classification standards for the pore seam.

[0044] According to one aspect of the present invention, a lamellar seam development segment identification device is provided, comprising:

[0045] The acquisition unit is used to acquire dipole shear wave train data corresponding to each receiver obtained by acoustic logging in the study area, as well as the time window for calculating amplitude.

[0046] A transverse wave amplitude determination unit is used to determine the transverse wave amplitude corresponding to all receivers based on the dipole transverse wave train that is within the calculated amplitude time window.

[0047] The attenuation index determination unit is used to determine the attenuation index of the shear wave amplitude for each receiver, with the dense sandstone section on the shear wave amplitude as the baseline.

[0048] The shale segment identification unit is used to assign a value of 0 to the non-shale segment corresponding to the transverse wave amplitude attenuation index.

[0049] The identification unit is used to establish a classification standard for foliation fractures, classify the transverse wave amplitude attenuation index according to the classification standard, and identify the foliation fracture development segment of the shale segment according to the classification result.

[0050] According to one aspect of the present invention, an electronic device is provided, comprising:

[0051] processor;

[0052] Memory used to store processor-executable instructions;

[0053] The processor is configured to execute the above-described page seam development segment identification method.

[0054] According to one aspect of the present invention, a computer-readable storage medium is provided having computer program instructions stored thereon, which, when executed by a processor, implement the above-described page seam development segment identification method.

[0055] The present invention has at least the following beneficial effects:

[0056] This invention proposes a method, device, equipment, and medium for identifying foliation fracture development sections. Based on the sensitivity of shear wave amplitude to horizontal / low-angle microfractures, the invention utilizes the shear wave amplitude attenuation of dipole shear wave trains to identify foliation fracture development sections, quantitatively evaluate the foliation fracture development, and provide technical support for the optimal selection of reservoir geological sweet spots. Attached Figure Description

[0057] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present invention and, together with the specification, serve to explain the technical solutions of the present invention.

[0058] Figure 1 A flowchart illustrating a method for identifying lamellar suture development segments according to an embodiment of the present invention is shown.

[0059] Figure 2 The diagram shows shear wave trains of core experimental samples measured under different fracture widths according to an embodiment of the present invention.

[0060] Figure 3 This diagram illustrates a time window for calculating transverse wave amplitude according to an embodiment of the present invention.

[0061] Figure 4 The diagram shows the calculated amplitude of the dipole shear wave in the target well according to an embodiment of the present invention.

[0062] Figure 5 A graph showing the calculation results of the dipole shear wave amplitude attenuation index of the target well according to an embodiment of the present invention is displayed.

[0063] Figure 6 This diagram shows the results of target well shale section identification according to an embodiment of the present invention;

[0064] Figure 7 This illustrates the shear wave amplitude attenuation index of the target well shale section according to an embodiment of the present invention;

[0065] Figure 8 This diagram illustrates the relationship between the target well fracture density and the shear wave amplitude attenuation index according to an embodiment of the present invention.

[0066] Figure 9 This diagram shows the results of identifying the developmental segment of the target well fracture according to an embodiment of the present invention.

[0067] Figure 10 A comparison diagram of the target well shear wave amplitude attenuation index and the core description foliation density is shown according to an embodiment of the present invention. Detailed Implementation

[0068] Various exemplary embodiments, features, and aspects of the present invention will now be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote elements that have the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.

[0069] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0070] In this document, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Furthermore, the term "at least one" in this document means any combination of at least two of any one or more elements. For example, including at least one of A, B, and C can mean including any one or more elements selected from the set consisting of A, B, and C.

[0071] Furthermore, to better illustrate the present invention, numerous specific details are set forth in the following detailed embodiments. Those skilled in the art will understand that the present invention can be practiced without certain specific details. In some instances, methods, means, elements, and circuits well known to those skilled in the art have not been described in detail in order to highlight the spirit of the invention.

[0072] Figure 1 A flowchart illustrating a method for identifying lamellar suture development segments according to an embodiment of the present invention is shown. Figure 2 The diagram shows shear wave trains of core experimental samples measured under different fracture widths according to an embodiment of the present invention. Figure 3 This diagram illustrates a time window for calculating transverse wave amplitude according to an embodiment of the present invention. Figure 4 The diagram shows the calculated amplitude of the dipole shear wave in the target well according to an embodiment of the present invention. Figure 5 A graph showing the calculation results of the dipole shear wave amplitude attenuation index of the target well according to an embodiment of the present invention is displayed. Figure 6 This diagram shows the results of target well shale section identification according to an embodiment of the present invention; Figure 7 This illustrates the shear wave amplitude attenuation index of the target well shale section according to an embodiment of the present invention; Figure 8 This diagram illustrates the relationship between the target well fracture density and the shear wave amplitude attenuation index according to an embodiment of the present invention. Figure 9 This diagram shows the results of identifying the developmental segment of the target well fracture according to an embodiment of the present invention. Figure 10 This diagram illustrates a comparison between the target well's shear wave amplitude attenuation index and the core description fracture density, according to an embodiment of the present invention. Figure 1-10As shown, a method for identifying shale fracture development segments includes: Step S01: acquiring dipole shear wave train data and amplitude calculation time window for each receiver obtained by sonic logging in the study area; Step S02: determining the shear wave amplitude corresponding to each receiver based on the dipole shear wave train within the amplitude calculation time window; Step S03: determining the shear wave amplitude attenuation index corresponding to each receiver using the tight sandstone segment on the shear wave amplitude as a baseline; Step S04: assigning a value of 0 to the non-shale segment corresponding to the shear wave amplitude attenuation index; Step S05: establishing a shale fracture classification standard, classifying the shear wave amplitude attenuation index according to the classification standard, and identifying the shale fracture development segment based on the classification result.

[0073] The method for identifying the developmental segment of lamellar sutures provided in this embodiment of the invention specifically includes the following steps:

[0074] Step S01: Obtain the dipole shear wave train data corresponding to each receiver obtained by sonic logging in the study area and calculate the amplitude time window.

[0075] In the embodiments of this invention, research shows that shear wave time difference is a shear wave that cannot propagate in fluids. The amplitude attenuation of shear waves is sensitive to low-angle microcracks with a dip angle of less than 33 degrees; that is, the more developed the low-angle microcracks, the greater the amplitude attenuation of the shear waves. Figure 2 As shown, the wider the fracture, the smaller the amplitude of the shear wave, and the greater the amplitude attenuation. Shale reservoirs are mainly composed of low-angle foliation fractures due to the weak hydrodynamic environment of the sedimentary environment. Therefore, this invention uses the amplitude attenuation index of dipole shear waves to evaluate the foliation fracture development segment.

[0076] In this invention, before obtaining the calculation amplitude time window corresponding to each receiver, the method for determining the calculation amplitude time window includes: obtaining the arrival time of the transverse wave corresponding to each receiver; and determining the calculation amplitude time window on the dipole transverse wave train corresponding to each receiver, with the arrival time of the transverse wave corresponding to the receiver as the start time and the arrival time of the transverse wave plus a predetermined time as the end time.

[0077] In this invention, the predetermined time is 600 μs.

[0078] In this invention, the method for determining the shear wave arrival time before obtaining the shear wave arrival time corresponding to each receiver includes: obtaining the shear wave time difference and the shear wave arrival time of the first receiver; and determining the shear wave arrival time of other receivers based on the shear wave time difference and the shear wave arrival time of the first receiver.

[0079] In this embodiment of the invention, the acoustic logging (XMAC) uses eight receivers. Each receiver acquires a corresponding dipole shear wave train logging curve. At the same time, it can obtain the shear wave arrival time data and shear wave time difference data corresponding to each receiver.

[0080] Before calculating the shear wave amplitude, it is necessary to determine the data range selected for the calculation, i.e., the calculation window. First, determine the start time, which is the shear wave arrival time T for the corresponding receiver. The shear wave arrival time T for the first receiver is known data, and the shear wave time difference between each receiver is known. Therefore, based on the shear wave arrival time of the first receiver and the shear wave time difference between the receivers, the shear wave arrival times T for the remaining 7 receivers can be calculated.

[0081] The start time is T, the arrival time of the shear wave. The predetermined time (window opening time), 600µs, is added to this start time to determine the end time. For example... Figure 3 As shown, the amplitude values ​​within the amplitude duration window between the two dashed lines are the data used to calculate the transverse wave amplitude. This amplitude duration window typically needs to include 2 to 3 sound wave propagation cycles.

[0082] Step S02: Determine the transverse wave amplitude corresponding to each receiver based on the dipole transverse wave train that is within the calculated amplitude time window.

[0083] In this invention, the method for determining the transverse wave amplitude corresponding to each receiver based on the dipole transverse wave train within the calculation amplitude time window includes: determining the transverse wave amplitude corresponding to the receiver using equation (1);

[0084]

[0085] Where: AMP i denoted as λ, where λ is the transverse wave amplitude of the i-th receiver; M is the total number of sampling points within the time window (the time window for calculating amplitude); and WAVE(i) is the amplitude of the i-th sampling point, in λ.

[0086] In this embodiment of the invention, the amplitude (transverse wave amplitude) of the transverse wave train of the XMAC dipole transverse wave at the eight receivers is calculated using the dipole transverse wave train within the amplitude calculation window as input. That is, the average amplitude value of all sampling points within the time window from the arrival time T to T+600us is calculated according to formula (1). The final calculation result is as follows: Figure 4 As shown, Figure 4 The last track is the transverse wave amplitude curve calculated for the eight receivers.

[0087] Step S03: Using the dense sandstone section on the shear wave amplitude as the baseline, determine the shear wave amplitude attenuation index corresponding to all receivers.

[0088] In this invention, the method for determining the baseline before using the dense sandstone segment on the shear wave amplitude as the baseline includes: determining the location of the maximum value of the shear wave amplitude as the baseline.

[0089] In this invention, the method of determining the shear wave amplitude attenuation index of all receivers by taking the dense sandstone section on the shear wave amplitude as the baseline includes: determining the shear wave amplitude attenuation amplitude of each receiver using Equation (2) based on the shear wave amplitude and the baseline.

[0090]

[0091] In the formula: Anis i The attenuation index of the transverse wave amplitude (wave train) for the i-th receiver is %, %. i Let be the transverse wave amplitude of the i-th receiver, in dB; AMP ib denoted as the baseline value (db) of the transverse wave train amplitude of the fracture-undeveloped dense sandstone segment of the i-th receiver;

[0092] The average value of the shear wave amplitude attenuation of all the receivers is obtained, which is the shear wave amplitude attenuation index corresponding to all the receivers.

[0093] In this embodiment of the invention, the maximum value of the shear wave amplitude on the shear wave amplitude curve corresponds to a dense sandstone segment with undeveloped fractures, such as... Figure 5 As shown, the baseline is the location with the maximum shear wave amplitude on the downhole side of the target well. Using a tight sandstone section with undeveloped fractures as the baseline, the shear wave amplitude attenuation index Anis for each of the eight receivers is calculated using formula (2). i。

[0094] Then, the average value of the attenuation amplitude of the 8 receivers is calculated, i.e., formula (3), to obtain the transverse wave amplitude attenuation index Anis corresponding to all receivers.

[0095]

[0096] In the formula: Anis is the attenuation index of the transverse wave amplitude for N receivers, %.

[0097] The attenuation amplitude (attenuation index) of the 8 receiver waveforms was calculated according to formula (2), and the results are as follows: Figure 5 The second to last curve is shown; based on formula (3), the average value of the 8 attenuation index curves is calculated to obtain the attenuation index results of the dipole shear waves of all receivers as shown. Figure 5 The last one is shown in the middle.

[0098] Step S04: Assign a value of 0 to the non-shale segment corresponding to the transverse wave amplitude attenuation index.

[0099] In this invention, before assigning a value of 0 to the non-shale segment corresponding to the shear wave amplitude attenuation index, the method for identifying the non-shale segment includes: acquiring sonic transit time and natural gamma logging curves; identifying reservoir shale segments based on the sonic transit time and natural gamma logging curves; and identifying the non-shale segment in the shear wave amplitude attenuation index other than the portion corresponding to the shale segment.

[0100] In this invention, the method for identifying reservoir shale sections based on the sonic transit time and natural gamma ray logging curves includes: adjusting the scale range of the sonic transit time logging curves and natural gamma ray logging curves to a predetermined scale range; superimposing the natural gamma ray and sonic transit time logging curves, and determining, after superposition, that the portion of the natural gamma ray logging curve to the right of the sonic transit time logging curve is the shale section.

[0101] In this invention, the predetermined scale range of the sonic transit time logging curve is 140-40 μS / ft; the predetermined scale range of the natural gamma logging curve is 0-150 API.

[0102] In this embodiment of the invention, since shale fractures only exist in shale sections, it is necessary to identify the shale sections and use sonic transit time and natural gamma logging curves to identify the shale sections.

[0103] The specific approach is as follows: Due to the high organic matter content in shale sections, they exhibit higher natural gamma ray and higher sonic transit time compared to mudstone sections. The sonic transit time (AC) logging curve scale range is adjusted to 140-40 μS / ft, and the natural gamma ray logging curve scale range is adjusted to 0-150 API. This scale range is a universal scale range corresponding to the lithological boundaries of logging and coring.

[0104] By placing the natural gamma ray and acoustic transit time curves on the same track, the section where the natural gamma ray curve is to the right of the acoustic transit time curve represents the shale segment. In other words, the portion where the natural gamma ray curve exceeds the acoustic transit time curve represents the shale segment. Figure 6 As shown, in the last shale identification, the left side is an overlay diagram of the sonic transit time curve and the natural gamma curve, and the right side is the reservoir shale section determined based on the overlay diagram.

[0105] Excluding the shale section, the remaining portion is the non-shale section. The shear wave amplitude attenuation index corresponding to the non-shale section is assigned a value of 0, and only the shear wave amplitude attenuation index of the shale section is retained. For example... Figure 7 As shown, Figure 7 The last one is the shear wave amplitude attenuation index of the non-shale section after assigning a value of 0 to the remaining shear wave amplitude attenuation index of the shale section.

[0106] Step S05: Establish a classification standard for foliation fractures, classify the shear wave amplitude attenuation index according to the classification standard, and identify the foliation fracture development segment of the shale segment according to the classification result.

[0107] In this invention, the method for establishing a classification standard for foliation fractures includes: conducting core experiments on target wells in the study area to obtain core foliation fracture density range data; dividing the foliation fracture density range data into several level ranges; plotting the relationship curve between the core foliation fracture density and the shear wave amplitude attenuation index; determining the shear wave amplitude attenuation index level range corresponding to each foliation fracture density level range based on the relationship curve; and sorting all the shear wave amplitude attenuation index level ranges in descending order to correspond to several ascending classification levels, which are the foliation fracture classification standards.

[0108] In this embodiment of the invention, core experiments were conducted on the target wells in the study area to obtain the distribution of foliation fracture density, i.e., a description of foliation fracture density in the core. Taking the Jurassic shale of the Sichuan-Chongqing region as an example, statistical analysis showed that the foliation fracture density in the core of the Jurassic shale of the Sichuan-Chongqing region is mainly distributed between 0 and 600 fractures / meter, i.e., the range of foliation fracture density in the core is 0 to 600 fractures / meter.

[0109] Based on the pore density range data, an equal division principle can be adopted to divide it into several level ranges. For example, the 0-600 range can be divided into four level ranges: greater than or equal to 600, less than 600 but greater than or equal to 400, less than 400 but greater than or equal to 200, and less than 200. Alternatively, the division can be based on the specific conditions of the study area and the needs of the division, such as dividing it into: greater than or equal to 500, less than 500 but greater than or equal to 300, less than 300 but greater than or equal to 150, and less than 150.

[0110] Based on the core sampling depth and the corresponding depth shale segment transverse wave amplitude attenuation index obtained from step S04 above, a relationship curve between the two is established, such as... Figure 8 As shown, based on the four levels of the shear wave density range defined above, the corresponding transverse wave amplitude attenuation index value can be found on the relationship curve, which is the four levels of the transverse wave amplitude attenuation index range limit value.

[0111] If the pore density md level range is md≥500 pores / meter, and the corresponding transverse wave amplitude attenuation index level range is Anis≥70%, then its corresponding pore classification level is defined as: Class I layer (Type I layer).

[0112] If the density level of the pore fracture is 500 > md ≥ 300 fractures / meter, and the corresponding transverse wave amplitude attenuation index is 70% > Anis ≥ 40%, then the corresponding pore fracture classification level is defined as: Class II layer (second-class layer).

[0113] If the density level of the pore fracture is 300 > md ≥ 150 fractures / meter, and the corresponding transverse wave amplitude attenuation index is 40% > Anis ≥ 20%, then the corresponding pore fracture classification level is defined as: Class III layer (third-class layer).

[0114] If the density level of the pore layer is md < 150 pores / meter, and the corresponding transverse wave amplitude attenuation index level is Anis < 20%, then the corresponding pore layer classification level is defined as: Class IV layer (fourth category layer).

[0115] The shear wave amplitude attenuation index calculated from the target well was correlated with the shale fracture classification criteria. Layers corresponding to the shear wave amplitude attenuation index at Class I levels showed the best shale fracture development, and so on, with Class IV layers showing the worst. The final classification and evaluation results of shale fracture development in the target well shale section of the study area are as follows: Figure 9 As shown, Figure 9 The rightmost channel shows the classification and identification results of foliation fractures. The target well has relatively well-developed foliation fractures at the bottom of the Dong'er and Ma'anshan sections. The foliation fracture development index has a good correlation with the core foliation fracture density.

[0116] like Figure 10 The image shows the shale oil section of the Qingshankou Formation, the target well in the Gulong Oilfield of the study area. The core samples from this well were described for foliation fracture density. The lower Q1-Q3 strata showed high foliation fracture density and a correspondingly high shear wave amplitude attenuation index, while the Q4-Q9 strata showed low foliation fracture density and a correspondingly low shear wave amplitude attenuation index. The comparison shows that foliation fracture density and the shear wave amplitude attenuation index exhibit a consistent trend: the higher the foliation fracture density, the greater the shear wave amplitude attenuation index. This demonstrates that the method of this invention is effective in evaluating foliation fracture development.

[0117] It is understood that the various method embodiments mentioned above in this invention can be combined with each other to form combined embodiments without violating the principle and logic. Due to space limitations, this invention will not elaborate further.

[0118] The execution entity of the page seam development segment identification method can be a page seam development segment identification device. For example, the page seam development segment identification method can be executed by a terminal device, a server, or other processing devices. The terminal device can be a user equipment (UE), mobile device, user terminal, terminal, cellular phone, cordless phone, personal digital assistant (PDA), handheld device, computing device, vehicle-mounted device, wearable device, etc. In some possible implementations, the page seam development segment identification method can be implemented by a processor calling computer-readable instructions stored in memory.

[0119] Those skilled in the art will understand that, in the above-described method of the specific implementation, the order in which each step is written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of each step should be determined by its function and possible internal logic.

[0120] This invention also proposes a shale fracture development segment identification device, comprising: an acquisition unit for acquiring dipole shear wave train data and amplitude calculation time window for each receiver obtained by sonic logging in the study area; a shear wave amplitude determination unit for determining the shear wave amplitude corresponding to all receivers based on the dipole shear wave train within the amplitude calculation time window; an attenuation index determination unit for determining the shear wave amplitude attenuation index corresponding to each receiver using the tight sandstone segment on the shear wave amplitude as a baseline; a shale segment identification unit for assigning a value of 0 to the non-shale segment corresponding to the shear wave amplitude attenuation index; and an identification unit for establishing a shale fracture classification standard, classifying the shear wave amplitude attenuation index according to the classification standard, and identifying the shale fracture development segment based on the classification result.

[0121] In some embodiments, the functions or modules and units included in the apparatus provided by the present invention can be used to execute the methods described in the above method embodiments. The specific implementation can be referred to the description of the above method embodiments, and for the sake of brevity, it will not be repeated here.

[0122] This invention also proposes a computer-readable storage medium storing computer program instructions, which, when executed by a processor, implement the aforementioned page seam development segment identification method. The computer-readable storage medium can be a non-volatile computer-readable storage medium.

[0123] This invention also proposes an electronic device, comprising: a processor; and a memory for storing processor-executable instructions; wherein the processor is configured to execute the above-described page seam development segment identification method. The electronic device may be provided as a terminal, a server, or other form of device.

[0124] Shale fractures in shale reservoirs are generally characterized by continuous, segmented development, significantly enhancing reservoir storage and permeability. For shale reservoirs, well sections with well-developed foliation fractures exhibit higher productivity. This invention addresses the characteristic that shear wave amplitude is highly sensitive to horizontal / low-angle microfractures, and that shear wave amplitude attenuation is the true response of foliation fractures. By utilizing the shear wave amplitude attenuation of dipole shear wave trains to identify and quantitatively evaluate foliation fracture development, this invention has achieved good application results in multiple blocks and stratigraphic levels, demonstrating strong applicability and a wider range of applications, providing technical support for the optimal selection of reservoir geological sweet spots.

[0125] This invention has been experimentally applied in shale oil and gas fields such as the Jurassic system in the Sichuan-Chongqing region, the Qingshankou Formation in the Gulong area, and the Longmaxi Formation in the Haiba area of ​​Zhejiang Oilfield, and has achieved excellent results. This demonstrates that the method of this invention has wide applicability, provides technical support for predicting sweet spots in shale reservoirs, and designs fracturing and perforation schemes, reduces coring costs, and has great economic value and promising prospects for promotion.

[0126] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method for identifying a segment of a schistosity joint development, characterized by, The method comprises the following steps: obtaining the data of the transverse wave train of each receiver corresponding to the dipole obtained by acoustic logging in the research area and calculating the amplitude time window window; determining the transverse wave amplitude corresponding to all receivers according to the transverse wave train in the calculation amplitude time window window; taking the dense sandstone segment on the transverse wave amplitude as the baseline to determine the transverse wave amplitude attenuation index corresponding to each receiver; assigning 0 to the non-shale segment corresponding in the transverse wave amplitude attenuation index; establishing a classification standard for the bedding seam, and classifying the transverse wave amplitude attenuation index according to the classification standard, and identifying the bedding seam development segment of the shale segment according to the classification result.

2. The method according to claim 1, wherein Before the step of obtaining the calculation amplitude time window window corresponding to each receiver, the method comprises the following steps: obtaining the transverse wave arrival time corresponding to each receiver; determining the calculation amplitude time window window on the transverse wave train corresponding to each receiver, taking the transverse wave arrival time corresponding to the receiver as the starting time, and taking the transverse wave arrival time plus a predetermined time as the ending time.

3. The method for identifying the bedding seam development segment according to claim 2, wherein: the predetermined time is 600us.

4. The method according to claim 2, wherein Before the step of obtaining the transverse wave arrival time corresponding to each receiver, the method comprises the following steps: obtaining the transverse wave time difference and the transverse wave arrival time of the first receiver; determining the transverse wave arrival time of other receivers according to the transverse wave time difference and the transverse wave arrival time of the first receiver.

5. The method according to claim 1, wherein Before the step of taking the dense sandstone segment on the transverse wave amplitude as the baseline, the method comprises the following steps: determining the maximum value of the transverse wave amplitude as the baseline.

6. The method according to claim 1, wherein Before the step of assigning 0 to the non-shale segment corresponding in the transverse wave amplitude attenuation index, the method comprises the following steps: obtaining the acoustic time difference and the natural gamma logging curve; identifying the reservoir shale segment according to the acoustic time difference and the natural gamma logging curve; the part other than the part corresponding to the shale segment in the transverse wave amplitude attenuation index is the non-shale segment.

7. The method according to claim 6, wherein The method for identifying the reservoir shale segment according to the acoustic time difference and the natural gamma logging curve comprises the following steps: adjusting the scale range of the acoustic time difference logging curve and the natural gamma logging curve to a predetermined scale range; superimposing the natural gamma and acoustic time difference logging curves, and determining the part corresponding to the right side of the natural gamma logging curve in the acoustic time difference logging curve as the shale segment after superimposition.

8. The method for identifying the bedding seam development segment according to claim 7, wherein: the predetermined scale range of the acoustic time difference logging curve is 140-40us / ft; the predetermined scale range of the natural gamma logging curve is 0-150API.

9. The method according to claim 1, wherein, The method for determining the transverse wave amplitude corresponding to each receiver according to the transverse wave train in the calculation amplitude time window window comprises the following steps: determining the transverse wave amplitude corresponding to the receiver by using formula (1); where: AMP i is the amplitude of the shear wave for the ith receiver, db; M is the total number of samples in the time window; and WAVE(i) is the amplitude of the ith sample, db.

10. The method according to claim 1, wherein, The method for determining the transverse wave amplitude attenuation index corresponding to all receivers by taking the dense sandstone segment on the transverse wave amplitude as the baseline comprises the following steps: According to the shear wave amplitude and the baseline, a shear wave amplitude attenuation amplitude of each receiver is determined by using formula (2); Anis i is the amplitude attenuation exponent for the ith receiver, %; AMP i is the amplitude of the ith receiver, db; AMP ib is the baseline value for the ith receiver, db; An average value of the shear wave amplitude attenuation amplitudes of all the receivers is calculated as a shear wave amplitude attenuation index corresponding to the all receivers.

11. The method according to claim 1, wherein, The method for establishing the classification standard of the shale foliation joint comprises: Core experiments are performed on target wells in a study area to obtain core shale foliation joint density range data; According to the shale foliation joint density range data, the data is divided into several level ranges by using a uniform division principle; A core shale foliation joint density and shear wave amplitude attenuation index relationship curve is drawn; According to the relationship curve, a shear wave amplitude attenuation index level range corresponding to each shale foliation joint density level range is determined; After all the shear wave amplitude attenuation index level ranges are sorted in descending order, several ascending classification levels are respectively corresponded, and the classification level is a shale foliation joint classification standard.

12. A device for identifying a segment of a schistosity joint development, characterized in that The method comprises: An acquisition unit is configured to acquire dipole shear wave train data corresponding to each receiver and a calculation amplitude time window window obtained by using sonic logging in a study area; A shear wave amplitude determination unit is configured to determine shear wave amplitudes corresponding to all receivers according to the dipole shear wave train in the calculation amplitude time window window; An attenuation index determination unit is configured to take a tight sandstone segment of the shear wave amplitude as a baseline to determine a shear wave amplitude attenuation index corresponding to each receiver; A shale segment identification unit is configured to assign a non-shale segment corresponding to the shear wave amplitude attenuation index as 0; An identification unit is configured to establish a shale foliation joint classification standard, perform category division on the shear wave amplitude attenuation index according to the classification standard, and identify a shale foliation joint development segment of a shale segment according to a category division result.

13. An electronic device, comprising: The method comprises: A processor; A memory for storing processor-executable instructions; The processor is configured to call the instructions stored in the memory to execute the method in any one of claims 1 to 11.

14. A computer-readable storage medium having stored thereon computer program instructions, wherein, The computer program instructions are executed by the processor to implement the method in any one of claims 1 to 11.

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