Shale oil hydrocarbon source rock quality logging evaluation method and device

Abstract

The invention relates to the field of oil and gas field exploration and development, in particular to a shale oil hydrocarbon source rock quality logging evaluation method and device.The method comprises the steps that the total organic carbon content of kerogen of all points in a research area is determined according to the total organic carbon content of a stratum and the total organic carbon content of crude oil contained in the stratum; determining the effective point of the total organic carbon content of the kerogen from each point in the research area according to the lower limit value of the total organic carbon content of the kerogen contributing to reservoir formation; determining a hydrocarbon source rock development section in the research area layer by layer according to the depth of the effective point of the total organic carbon content of the kerogen; determining the effective thickness of a layer section corresponding to each effective point in each layer section in the hydrocarbon source rock development section; and evaluating the quality of the hydrocarbon source rock stratum section according to the effective thickness and the total organic carbon content of kerogen at the effective point. According to the scheme, on the basis of shale oil kerogen total organic carbon content evaluation and effective thickness statistics, a foundation is laid for analyzing a source-reservoir configuration relation and objectively evaluating shale oil resource potential and scale.

Description

Technical Field

[0001] This manual relates to the field of oil and gas field exploration and development, and in particular to a well logging evaluation method and device for shale oil source rock quality. Background Technology

[0002] In recent years, shale oil has increasingly become a key area of ​​exploration and development. Accurate evaluation of the quality of shale oil source rocks is crucial for classifying and assessing the hydrocarbon generation potential of shale oil and objectively evaluating the scale of shale oil resources. Currently, the quality of medium-to-high maturity shale oil source rocks is mainly described through factors such as organic matter abundance, organic matter maturity, and organic matter type.

[0003] For shale oil in a specific block and stratum, the organic carbon maturity and kerogen type can be considered to be basically constant. Therefore, the quality of the source rock can be simplified to the change in organic matter abundance in the vertical direction. The total organic carbon content is the most commonly used parameter for evaluating organic matter abundance.

[0004] Existing methods for evaluating source rock quality based on well logging data have two main problems. One method calculates the total organic carbon content of kerogen as the sum of the total organic carbon content of crude oil contained in the formation, which fails to reflect the total organic carbon content of kerogen and does not take into account the characteristics of shale oil source-reservoir symbiosis. The other method does not consider the influence of the effective thickness of the source rock, or although it does consider the influence of the effective thickness, due to misunderstandings of the concepts of total organic carbon content and effective thickness, the statistical results are significantly inconsistent with the actual situation. Summary of the Invention

[0005] To address the problems of existing technologies, this specification provides a method and apparatus for evaluating the quality of shale oil source rocks through logging.

[0006] This specification provides a well logging evaluation method for shale oil source rock quality. The method includes: determining the total organic carbon (TOC) content of kerogen at each point in the study area based on the total organic carbon (TOC) content of the formation and the total organic carbon (TOC) content of the crude oil contained in the formation, wherein the TOC content of the formation is calculated based on different well logging data; determining effective points of TOC content from each point in the study area based on the lower limit of TOC content of kerogen that contributes to hydrocarbon accumulation; determining the source rock development sections in the study area layer by layer based on the depth of the effective TOC content points of kerogen; determining the effective thickness corresponding to each effective point in each layer of the source rock development section; and evaluating the quality of each layer of the source rock based on the effective thickness and the TOC content of the effective points of kerogen.

[0007] According to one aspect of the embodiments of this specification, determining the source rock development segment in the study area layer by layer based on the depth of the effective point of total organic carbon content of kerogen in the study area includes: determining the effective point of total organic carbon content of kerogen in the same depth range in the study area as a segment; determining corresponding segments for all depth ranges in the study area, and all segments forming a source rock development segment.

[0008] According to one aspect of the embodiments of this specification, determining effective points for total organic carbon content of kerogen from various points in the study area based on a lower limit value of total organic carbon content of kerogen that contributes to hydrocarbon accumulation includes: selecting points where the total organic carbon content of kerogen is greater than or equal to the lower limit value of total organic carbon content of kerogen at various points in the study area; and determining the points as effective points for total organic carbon content of kerogen.

[0009] According to one aspect of the embodiments of this specification, determining the effective thickness corresponding to each effective point in each layer of the source rock development section includes: determining the top depth and bottom depth at the location of the effective point based on well logging data; and determining the effective thickness of the layer corresponding to the effective point based on the difference between the bottom depth and the top depth.

[0010] According to one aspect of the embodiments of this specification, the total organic carbon content of the formation is determined by: determining the uranium content based on the uranium content curve of the natural gamma ray spectrum in the natural gamma ray spectroscopy logging data; Among them, TOC k The total organic carbon content of kerogen is represented by ; U represents the uranium content obtained from natural gamma ray spectroscopy logging data; A, B, C, and D are empirical parameters and are dimensionless.

[0011] According to one aspect of the embodiments of this specification, determining the quality of each segment of the source rock based on the thickness and the total organic carbon content of the kerogen at the effective point includes: determining the quality of the source rock corresponding to the effective point based on the product of the thickness and the total organic carbon content of the kerogen at the effective point.

[0012] According to one aspect of the embodiments of this specification, evaluating the quality of each segment of the source rock based on the effective thickness and the total organic carbon content of the kerogen at the effective points includes: determining the source rock quality value of each effective point in each segment of the source rock based on the effective thickness and the total organic carbon content of the kerogen at the effective points; determining the source rock quality value set of the segment based on the source rock quality values ​​of each effective point in the same segment; and determining the quality of the segment of the source rock based on the preset source rock evaluation value and the source rock quality set of the segment.

[0013] This specification provides an embodiment of a shale oil source rock quality logging evaluation device. The device includes: a kerogen total organic carbon content determination unit, used to determine the kerogen total organic carbon content at each point in the study area based on the formation total organic carbon content and the total organic carbon content of the crude oil contained in the formation, wherein the formation total organic carbon content is calculated based on different logging data; an effective point determination unit, used to determine effective points of kerogen total organic carbon content from each point in the study area based on the lower limit value of kerogen total organic carbon content that contributes to hydrocarbon accumulation; a development section determination unit, used to determine the source rock development section in the study area layer by layer based on the depth of the effective points of kerogen total organic carbon content; a section thickness determination unit, used to determine the effective thickness of the section corresponding to each effective point in each section of the source rock development section; and an evaluation unit, used to evaluate the quality of each section of the source rock based on the effective thickness and the kerogen total organic carbon content of the effective points.

[0014] This specification also provides a computer device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the hydrocarbon source rock quality evaluation method.

[0015] This specification also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the source rock quality evaluation method.

[0016] This invention, based on the evaluation of total organic carbon content and effective thickness statistics of kerogen in shale oil, calculates source rock quality parameters for new wells using conventional or new logging data, enabling rapid classification of source rock quality. This lays the foundation for analyzing source-reservoir configuration relationships and objectively assessing the potential and scale of shale oil resources. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments or prior art of this specification, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 The diagram shown is a flowchart of a well logging evaluation method for shale oil source rock quality according to an embodiment of this specification.

[0019] Figure 2 The diagram shown is a flowchart of a method for determining the hydrocarbon source rock development section in the study area layer by layer, according to an embodiment of this specification.

[0020] Figure 3The diagram shown is a flowchart of a method for determining the effective point of total organic carbon content in kerogen according to an embodiment of this specification.

[0021] Figure 4 The diagram shown is a flowchart of a method for determining the total organic carbon content of kerogen according to an embodiment of this specification.

[0022] Figure 5 The diagram shown is a flowchart of a method for evaluating the quality of each layer of source rock according to an embodiment of this specification.

[0023] Figure 6 The diagram shown is a schematic representation of a well logging evaluation example of source rock quality in a key well according to an embodiment of this specification.

[0024] Figure 7 The diagram shown is a structural schematic of a source rock quality evaluation device according to an embodiment of this specification.

[0025] Figure 8 The diagram shown is a structural schematic of a computer device according to an embodiment of this specification.

[0026] Explanation of symbols in the attached drawings:

[0027] 701. Unit for determining the total organic carbon content of kerogen;

[0028] 702. Effective point determination unit;

[0029] 703. Developmental stage determination unit;

[0030] 704. Layer thickness determination unit;

[0031] 705. Evaluation Unit;

[0032] 802. Computer equipment;

[0033] 804, Processor;

[0034] 806. Memory;

[0035] 808. Drive mechanism;

[0036] 810. Input / Output Module;

[0037] 812. Input devices;

[0038] 814. Output devices;

[0039] 816. Presentation equipment;

[0040] 818. Graphical User Interface;

[0041] 820. Network interface;

[0042] 822. Communication link;

[0043] 824. Communication bus. Detailed Implementation

[0044] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this specification.

[0045] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, apparatus, product, or device that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or devices.

[0046] This specification provides the operational steps of the methods described in the embodiments or flowcharts, but based on conventional or non-inventive labor, more or fewer operational steps may be included. The order of steps listed in the embodiments is merely one possible execution order among many and does not represent the only possible execution order. In actual system or device products, the methods shown in the embodiments or drawings can be executed sequentially or in parallel.

[0047] It should be noted that the shale oil source rock quality logging evaluation method and device described in this manual can be used in the field of oil and gas field exploration and development. This manual does not limit the application field of a single shale oil source rock quality logging evaluation method and device.

[0048] Figure 1 The diagram shown is a flowchart of a well logging evaluation method for shale oil source rock quality according to an embodiment of this specification. The system includes:

[0049] Step 101: Determine the total organic carbon content of kerogen at each point in the study area based on the total organic carbon content of the formation and the total organic carbon content of the crude oil contained in the formation. The total organic carbon content of the formation is calculated using different well logging data. In this step, different methods can be used to determine the total organic carbon content of the formation in the study area depending on the type of well logging data available. Further calculate the total organic carbon content of the crude oil contained in the formation in the study area, and subtract the total organic carbon content of the formation in the study area from the total organic carbon content of the crude oil contained in the formation to obtain the total organic carbon content of kerogen at each point in the study area.

[0050] Step 102: Based on the lower limit of the total organic carbon content of kerogen that contributes to hydrocarbon accumulation, determine the effective points for total organic carbon content of kerogen from various points in the study area.

[0051] In the embodiments described in this specification, not all formations with a total organic carbon content of kerogen greater than 0 effectively contribute to hydrocarbon accumulation. Based on comprehensive analysis of geochemical analysis and hydrocarbon accumulation studies, the lower limit or minimum value of total organic carbon content of kerogen that contributes to hydrocarbon accumulation can be taken as 0.4% to 0.6%.

[0052] This step selects effective points for total organic carbon content in kerogen from the study area in step 101, based on the lower limit of the total organic carbon content in kerogen. The total organic carbon content of kerogen at these effective points all exceeds the lower limit.

[0053] Step 103: Based on the depth of the effective points for total organic carbon content in kerogen, determine the source rock development sections in the study area layer by layer. In this step, each effective point has its own corresponding depth in the study area. For example, in the entire well section of a well in the study area, several effective points and their depth distribution data can be determined according to the aforementioned steps. Based on the depth distribution data of these effective points, effective points within the same depth range are considered as points in a layer of the source rock. In the embodiments of this specification, the layers constructed using the effective points for total organic carbon content in kerogen can constitute the source rock development sections. The source rock development sections may include multiple layers.

[0054] Step 104: Determine the effective thickness of the segment corresponding to each effective point in each layer of the source rock development section. In this step, the source rock development section refers to a rock segment rich in organic matter that can generate and expel oil and gas. Based on each layer of the source rock development section determined in Step 103, the thickness of the segment corresponding to each effective point in each layer is determined layer by layer. Since the total organic carbon content of the kerogen at the effective point is the effective content, it contributes to the oil and gas accumulation in the study area. Therefore, the thickness of the segment formed by the effective point can be called the effective thickness.

[0055] Step 105: Evaluate the quality of each layer of the source rock based on the effective thickness and the total organic carbon content of the kerogen at the effective points.

[0056] In the embodiments of this specification, after determining the effective thickness of the segment corresponding to each effective point and the total organic carbon content of the kerogen at each effective point, the effective thickness and total organic carbon content of the kerogen at each point in a segment composed of multiple effective points can be determined. Therefore, the quality of the source rock segment can be evaluated by comprehensively using the effective thickness and total organic carbon content of the kerogen at each point in the segment. By combining the calculation results of source rock quality parameters from multiple wells and the results of oil testing and production, statistical analysis is used to determine whether each segment of the source rock belongs to high-quality, medium-quality, or general source rock. Specifically, the source rock quality parameters corresponding to the effective points are determined by multiplying the thickness by the total organic carbon content of the kerogen at each effective point.

[0057] In this specification, the source rock quality parameters are calculated layer by layer for each layer of the source rock development section, with multiple source rock quality parameter values ​​for each layer. Specifically, the source rock quality parameters are calculated using the following formula: Wherein, SQ represents the source rock quality parameter; The total organic carbon content of kerogen that is greater than the lower limit of the total organic carbon content of kerogen, expressed as a percentage; H se This indicates the thickness of the source rock development section, specifically the thickness of each layer where the total organic carbon content of kerogen is greater than the lower limit of the total organic carbon content of kerogen, expressed in meters.

[0058] Figure 2 The diagram shown is a flowchart of a method for determining the hydrocarbon source rock development section in the study area layer by layer, according to an embodiment of this specification. The method specifically includes the following steps:

[0059] Step 201: Effective points with total organic carbon content of kerogen within the same depth range in the study area are identified as a single layer. In this embodiment of the specification, effective points at the same depth are identified as a single layer; in other embodiments, effective points at similar depths are identified as a single layer. The size of the same depth range can be determined according to actual operational needs. For example, effective points within a 5-meter depth range are identified as a single layer of source rock in the study area. As another example, effective points within a 10-meter depth range are identified as a single layer of source rock in the study area.

[0060] Step 202 involves determining corresponding stratigraphic segments for all depth ranges within the study area, with all segments constituting a source rock development segment. Based on step 201, multiple stratigraphic segments can be constructed from all valid points within the study area, collectively forming a source rock development segment. This source rock development segment is rich in organic matter.

[0061] Figure 3The diagram shown is a flowchart of a method for determining the effective point of total organic carbon content in kerogen according to an embodiment of this specification, which specifically includes the following steps:

[0062] Step 301: Based on the total organic carbon content of kerogen at each point in the study area, select points where the total organic carbon content of kerogen is greater than or equal to the lower limit value of the total organic carbon content of kerogen.

[0063] In this step, the lower limit of the total organic carbon content in kerogen is predetermined. Points with a total organic carbon content in kerogen greater than or equal to this lower limit effectively contribute to hydrocarbon accumulation. In the embodiments of this specification, the lower limit of the total organic carbon content in kerogen that effectively contributes to hydrocarbon accumulation in the study area can be set to 0.4%, 0.5%, or any other value within the range of 0.4% to 0.6%. The lower limit of the total organic carbon content in kerogen in the embodiments of this specification is set to avoid source rocks with low total organic carbon content but large thickness, and to avoid mistakenly evaluating such source rocks as high-quality source rocks.

[0064] Step 302: The point is determined as an effective point for total organic carbon content in kerogen. In the embodiments of this specification, points that meet the lower limit value of total organic carbon content in kerogen are considered effective points, and these effective points contribute effectively to the hydrocarbon accumulation in the target area.

[0065] In the embodiments of this specification, determining the effective thickness of each effective point corresponding to each effective point in each segment of the source rock development section includes: determining the top and bottom depths at the location of the effective point based on well logging data; and determining the effective thickness corresponding to the effective point based on the difference between the bottom and top depths. In the embodiments of this specification, well logging data can be used to determine the oil and gas-bearing formations and formation depths. Therefore, the location of the effective point can be determined based on the well logging data, combined with... Figure 3 The steps described in the specification further determine the top and bottom depths of the effective point's stratigraphic segment. Based on the difference between the bottom and top depths, the effective thickness of the corresponding stratigraphic segment is determined. In the embodiments of this specification, there are multiple effective points within a certain depth range of the stratum where the total organic carbon content of kerogen is greater than the lower limit. These multiple effective points form a stratigraphic segment. If the horizontal trend of the stratigraphic segment is gentle and uniform, then the difference between the bottom and top depths at each effective point in the stratigraphic segment is basically the same. The stratigraphic segment can be regarded as a uniformly distributed elongated shape, and the effective thickness at each effective point is basically the same. Therefore, by selecting one effective point and calculating the difference between the bottom and top depths at that point, the effective thickness of the stratigraphic segment can be determined.

[0066] If the horizontal slope of a stratigraphic segment is large and uneven, the difference between the bottom and top depths at each effective point may vary significantly. If the stratigraphic segment has an irregular shape, the effective thickness at each effective point will also differ. Therefore, multiple key points or all effective points can be selected, and the difference between the bottom and top depths at each point can be calculated separately. The summation and averaging of these differences will determine the effective thickness of the stratigraphic segment. Alternatively, based on the importance of each effective point in the stratigraphic sequence, the difference between the bottom and top depths at each point can be calculated separately, and different weights can be assigned to the calculated thickness values ​​before summing to determine the effective thickness of the stratigraphic segment. Figure 4 The diagram shown is a flowchart of a method for determining the total organic carbon content of kerogen according to an embodiment of this specification, which specifically includes the following steps:

[0067] Step 401: Determine the uranium content based on the uranium content curve of the natural gamma ray spectroscopy logging data. In this embodiment, the uranium content curve in the natural gamma ray spectroscopy logging reflects the changes in the content of radioactive uranium minerals in the formation. Because radioactive nuclides (e.g., uranium, thorium, potassium, etc.) in the formation continuously emit gamma rays, these rays can be received and recorded by logging instruments. By analyzing the gamma ray spectrum, the content of different radioactive nuclides in the formation can be determined, thereby plotting the corresponding content curves. Therefore, based on the uranium content curve, the content of radioactive uranium minerals in the formation of the study area can be determined.

[0068] In the implementation of this manual, natural gamma-ray spectroscopy logging data were collected to obtain uranium content curves (such as...). Figure 6 (As shown in the fifth curve in the middle).

[0069] Step 402: Calculate the total organic carbon content of kerogen using the formula.

[0070] Specifically, the formula is as follows:

[0071] Among them, TOC k The formula represents the total organic carbon content of kerogen; U represents the uranium content obtained from natural gamma-ray spectroscopy logging data; A, B, C, and D are empirical parameters, dimensionless. Specifically, the formula can also be in the following form:

[0072] Among them, TOC k The total organic carbon (TOC) content of kerogen is represented by denoted as ; U represents the uranium content obtained from natural gamma ray spectroscopy logging data. In the implementation of this specification, the more accurate TOC content of kerogen is calculated using the formula. k ,like Figure 6 As shown in the 7th curve.

[0073] In this specification, the total organic carbon content of the formation and the total organic carbon content of kerogen can be determined based on different well logging data. In one embodiment of this specification, under the condition of only conventional well logging data, the total organic carbon content of the formation is calculated using the ΔlgR method based on conventional three-porosity logging and resistivity logging data, and the total organic carbon content of the crude oil contained in the formation is subtracted to obtain the total organic carbon content of kerogen.

[0074] In another embodiment of this specification, under the condition of collecting conventional logging data and nuclear magnetic resonance logging data, the total organic carbon content of the formation is calculated using density and total porosity from nuclear magnetic resonance logging, and the total organic carbon content of the crude oil contained in the formation is subtracted to obtain the total organic carbon content of kerogen.

[0075] In another embodiment of this specification, under the condition of acquiring full-spectrum elemental logging data, the total organic carbon content of the formation is obtained by inverting the total organic carbon content of the formation using the full-spectrum elemental logging data, and then subtracting the total organic carbon content of the crude oil contained in the formation to obtain the total organic carbon content of kerogen.

[0076] In some embodiments of this specification, the total organic carbon content of the crude oil contained in the formation can be determined according to the following formula:

[0077] Among them, TOC oil φ represents the total organic carbon content of crude oil; K represents the conversion factor for converting the volumetric content of crude oil to its total organic carbon content; T S represents total porosity; o Oil saturation; ρ oil ρ represents the density of crude oil. b This represents the formation bulk density. Since the conversion factor, total porosity, oil saturation, crude oil density, and formation bulk density are all known quantities, the total organic carbon content of the crude oil can be calculated using the formula described above.

[0078] Figure 5 The diagram shown is a flowchart of a method for evaluating the quality of each layer of source rock according to an embodiment of this specification, which specifically includes the following steps:

[0079] Step 501: Determine the source rock quality value for each effective point in each layer of the source rock based on the effective thickness and the total organic carbon content of the kerogen at the effective point. In this step, the source rock quality value corresponding to each effective point in each layer can be determined by multiplying the effective thickness of the corresponding layer and the total organic carbon content of the kerogen at that effective point. Figure 6The curves in the rightmost column, from top to bottom, represent a segment of the hydrocarbon source rock. Each point on the curve corresponds to the SQ value for the valid points described in this specification, indicating the source rock quality. Most curves in this segment exceed the two SQ standard lines, which represent two different SQ values. The SQ standard lines can be used to determine the magnitude of the curve values ​​in different segments of the source rock relative to the corresponding SQ standard lines. The fact that most curves in this segment exceed the two SQ standard lines indicates that most valid points in this segment correspond to high-quality source rocks; a small portion of the curves lie between the two SQ standard lines, indicating that a small portion of valid points in this segment correspond to good or moderate-quality source rocks; and there are no valid points in this segment below the minimum SQ standard line.

[0080] Step 502: Based on the source rock quality values ​​of each effective point within the same stratigraphic segment, determine the source rock quality value set for that segment. The source rock quality values ​​of each effective point within the same stratigraphic segment are connected to form a source rock development segment curve, which is reflected in the graph as follows: Figure 6 The last column shows the curves, and the points on these curves represent the set of source rock quality values ​​for that layer of the source rock.

[0081] Step 503: Determine the quality of the source rock segment based on the preset source rock evaluation value and the source rock quality set of the segment.

[0082] In this step, source rock quality is evaluated using source rock quality values. Based on the calculation results of source rock quality parameters from multiple wells in the study area and the results of oil testing and production trials, statistical analysis is used to determine the value ranges of the source rock quality parameter SQ for high-quality, medium-quality, and general source rocks. The following source rock quality classification and evaluation criteria can then be established:

[0083] When SQ ≥ 2.4, the effective logging interval is determined to be a high-quality source rock (or, a Class I source rock); when 1.5 ≤ SQ < 2.4, the effective logging interval is determined to be a medium-quality source rock (or, a Class II source rock); when SQ < 1.5, the effective logging interval is determined to be a general source rock (or, a Class III source rock). In this specification, source rock quality parameters or values ​​are calculated using conventional or new logging data in a new well. Based on the source rock quality classification standards, rapid classification of source rock quality can be achieved.

[0084] Figure 6The diagram shown is a schematic representation of a source rock quality evaluation example from a key well in this specification. The first line represents depth; the second line represents the natural gamma ray curve (GRTO: total gamma ray curve; GRTC: uranium-removed gamma ray curve) and the wellbore caliber curve (CAL); the third line represents the three porosity curves (AC: acoustic transit time curve; CNL: neutron curve; DEN: density curve); the fifth line represents the lithological profile; and the sixth line represents the total organic carbon (TOC) content of the formation. t and the total organic carbon content (TOC) of kerogen k The seventh channel represents the classification results of source rock quality. The depth segment where "Projection 1" is located represents a Class I source rock development segment, the depth segment where "Projection 3" is located represents a Class II source rock development segment, and the depth segment where "Projection 2" is located represents a Class III source rock development segment.

[0085] like Figure 7 The diagram shown is a structural schematic of a shale oil source rock quality logging evaluation device according to an embodiment of this specification. The diagram illustrates the basic structure of the shale oil source rock quality logging evaluation device. The functional units and modules can be implemented using software, or using general-purpose chips or specific chips to evaluate the shale oil source rock quality. The device specifically includes:

[0086] The kerogen total organic carbon content determination unit 701 is used to determine the kerogen total organic carbon content at each point in the study area based on the formation total organic carbon content and the crude oil contained in the formation. The formation total organic carbon content is calculated based on different well logging data.

[0087] The effective point determination unit 702 is used to determine the effective points of total organic carbon content of kerogen from each point in the study area based on the lower limit value of total organic carbon content of kerogen that contributes to hydrocarbon accumulation.

[0088] Development segment determination unit 703 is used to determine the source rock development segments in the study area layer by layer based on the depth of the effective point of total organic carbon content in kerogen;

[0089] The segment thickness determination unit 704 is used to determine the effective thickness of each effective point in each segment of the source rock development segment;

[0090] Evaluation unit 705 is used to evaluate the quality of each layer of source rock based on the effective thickness and the total organic carbon content of kerogen at the effective point.

[0091] like Figure 8The diagram illustrates a computer device provided in an embodiment of this specification. The shale oil source rock quality logging evaluation method described in this application can be applied to this computer device. The computer device 802 may include one or more processors 804, such as one or more central processing units (CPUs), each of which can implement one or more hardware threads. The computer device 802 may also include any memory 806 for storing any kind of information, such as code, settings, data, etc. Non-limitingly, for example, the memory 806 may include any type of RAM, any type of ROM, flash memory, hard disk, optical disk, etc. More generally, any memory can use any technology to store information. Further, any memory can provide volatile or non-volatile retention of information. Further, any memory can represent a fixed or removable component of the computer device 802. In one case, when the processor 804 executes associated instructions stored in any memory or combination of memories, the computer device 802 can perform any operation of the associated instructions. The computer device 802 also includes one or more drive mechanisms 808 for interacting with any memory, such as a hard disk drive mechanism, an optical disk drive mechanism, etc.

[0092] Computer device 802 may also include an input / output module 810 (I / O) for receiving various inputs (via input device 812) and providing various outputs (via output device 814). A specific output mechanism may include a presentation device 816 and an associated graphical user interface (GUI) 818. In other embodiments, the input / output module 810 (I / O), input device 812, and output device 814 may be omitted, and the device may function solely as a computer device within a network. Computer device 802 may also include one or more network interfaces 820 for exchanging data with other devices via one or more communication links 822. One or more communication buses 824 couple the components described above together.

[0093] Communication link 822 can be implemented in any way, such as via a local area network, a wide area network (e.g., the Internet), a point-to-point connection, or any combination thereof. Communication link 822 may include any combination of hardwired links, wireless links, routers, gateway functions, name servers, etc., governed by any protocol or combination of protocols.

[0094] Corresponding to Figures 1 to 5 In addition to the methods described above, embodiments of this specification also provide a computer-readable storage medium storing a computer program that, when executed by a processor, performs the steps of the methods described above.

[0095] This specification also provides computer-readable instructions, wherein when a processor executes the instructions, the program therein causes the processor to perform the following... Figures 1 to 5 The method shown.

[0096] It should be understood that in the various embodiments of this specification, the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this specification.

[0097] It should also be understood that, in the embodiments of this specification, 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: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this specification generally indicates that the preceding and following related objects have an "or" relationship.

[0098] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed in this specification can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of each example have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this specification.

[0099] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0100] In the several embodiments provided in this specification, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the couplings or direct couplings or communication connections shown or discussed may be indirect couplings or communication connections through some interfaces, devices, or units, or they may be electrical, mechanical, or other forms of connection.

[0101] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of the embodiments described in this specification, depending on actual needs.

[0102] Furthermore, the functional units in the various embodiments of this specification can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0103] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this specification, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this specification. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0104] This specification uses specific embodiments to illustrate the principles and implementation methods of this specification. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this specification. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this specification. Therefore, the content of this specification should not be construed as a limitation of this specification.

Claims

1. A well logging evaluation method for shale oil source rock quality, characterized in that, The method includes: Based on the total organic carbon content of the formation and the total organic carbon content of the crude oil contained in the formation, the total organic carbon content of kerogen at each point in the study area was determined. The total organic carbon content of the formation was calculated based on different well logging data. Based on the lower limit of the total organic carbon content of kerogen that contributes to hydrocarbon accumulation, effective points for the total organic carbon content of kerogen were determined from various points in the study area. Based on the depth of the effective point of total organic carbon content in kerogen, the hydrocarbon source rock development section in the study area was determined layer by layer; Determine the effective thickness of the layer corresponding to each effective point in each layer of the hydrocarbon source rock development section; The quality of each layer of the source rock is evaluated based on the effective thickness and the total organic carbon content of the kerogen at the effective points.

2. The method according to claim 1, characterized in that, Based on the depth of the effective point of total organic carbon content in kerogen, the hydrocarbon source rock development sections in the study area were determined layer by layer, including: The effective points of total organic carbon content of kerogen within the same depth range in the study area are identified as a layer segment; The corresponding strata were determined for all depth ranges in the study area, and all strata constituted the source rock development section.

3. The method according to claim 1, characterized in that, Based on the lower limit of total organic carbon content in kerogen that contributes to hydrocarbon accumulation, the effective points for determining the total organic carbon content of kerogen from various points in the study area include: Based on the total organic carbon content of kerogen at each point in the study area, select points where the total organic carbon content of kerogen is greater than or equal to the lower limit value of the total organic carbon content of kerogen. The point was determined as the effective point for the total organic carbon content of kerogen.

4. The method according to claim 1, characterized in that, Determining the effective thickness of each effective point in each segment of the source rock development section includes: Based on well logging data, determine the top and bottom depths at the effective point locations; The effective thickness of the layer corresponding to the effective point is determined based on the difference between the bottom depth and the top depth.

5. The method according to claim 1, characterized in that, The total organic carbon content of kerogen was determined as follows: The uranium content is determined based on the uranium content curve of the natural gamma spectrum in the natural gamma spectrum logging data. The total organic carbon content of kerogen is calculated using the following formula: TOC k =10 Among them, TOC k The total organic carbon content of kerogen is represented by ; U represents the uranium content obtained from natural gamma ray spectroscopy logging data; A, B, C, and D are empirical parameters and are dimensionless.

6. The method according to claim 1, characterized in that, The quality evaluation of each layer of source rock based on the effective thickness and the total organic carbon content of the kerogen at the effective point includes: determining the quality of the source rock corresponding to the effective point based on the product of the thickness and the total organic carbon content of the kerogen at the effective point.

7. The method according to claim 1, characterized in that, The quality of each layer of the source rock is evaluated based on the effective thickness and the total organic carbon content of the kerogen at the effective points, including: Based on the effective thickness and the total organic carbon content of kerogen at the effective points, the source rock quality value of each effective point in each layer of the source rock is determined. Based on the source rock quality values ​​of each effective point in the same stratigraphic segment, determine the source rock quality value set of the stratigraphic segment; The quality of the source rock in the specified layer is determined based on the preset source rock evaluation value and the source rock quality set of the specified layer.

8. A well logging evaluation device for shale oil source rock quality, characterized in that, The device includes: The kerogen total organic carbon content determination unit is used to determine the total organic carbon content of kerogen at each point in the study area based on the total organic carbon content of the formation and the total organic carbon content of the crude oil contained in the formation. The total organic carbon content of the formation is calculated based on different well logging data. The effective point determination unit is used to determine the effective points of total organic carbon content of kerogen from various points in the study area based on the lower limit value of total organic carbon content of kerogen that contributes to hydrocarbon accumulation. The development segment determination unit is used to determine the source rock development segments in the study area layer by layer based on the depth of the effective point of total organic carbon content in kerogen; The segment thickness determination unit is used to determine the effective thickness of each effective point in each segment of the source rock development section; The evaluation unit is used to evaluate the quality of each layer of source rock based on the effective thickness and the total organic carbon content of the kerogen at the effective points.

9. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method according to any one of claims 1 to 7.

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