Method and system for determining carbonate mineral cause in rock

Abstract

The invention discloses a method and system for determining the cause of formation of carbonate minerals in rock, and the method comprises the steps: obtaining a to-be-analyzed rock sample, and carrying out the polishing of the rock sample; carrying out carbon plating treatment on the polished rock sample, carrying out carbonate mineral strip and argillaceous strip positioning on the rock sample subjected to the carbon plating treatment, and determining the position information of the carbonate mineral strip and the position information of the argillaceous strip; performing isotope detection on the rock sample based on the position information of the carbonate mineral strip and the position information of the argillaceous strip to obtain an isotope detection result, and determining the formation reason of the carbonate mineral of the rock sample based on the isotope detection result, according to the method, the positioning of different types of carbonate interlayers and argillaceous interlayers in the rock sample can be accurately obtained, the problem of low isotope analysis accuracy in argillaceous strips of micro-area carbonate rocks and surrounding rocks is solved, and the accuracy of analysis of the cause mechanism of the micro-area carbonate rocks is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas exploration and development, and in particular to a method and system for determining the genesis of carbonate minerals in rocks. Background Art

[0002] The main rock type in continental shale oil reservoirs is mostly gray mud shale. The genesis mechanism of carbonate minerals in gray mud shale is an important basic geological issue currently concerned with this type of shale oil reservoir.

[0003] The existing experimental analysis method for the formation mechanism of carbonate rocks is mainly the isotope analysis method, and its research object is mainly conventional carbonate reservoirs. The carbonate rock minerals in this type of reservoir are developed and distributed in a large area (areas above the centimeter scale) and the crystal types are relatively similar. Therefore, the isotope analysis of this type of rock samples is carried out using the human eye positioning method.

[0004] However, the development and distribution of carbonate interlayers (or bands) in continental shale oil reservoirs are relatively small (millimeter-micro-nanoscale) and there are certain differences in crystal types. When conducting isotope analysis on such rock samples, they will be greatly affected by the doping and contamination of other minerals, and the analysis results of the genetic mechanism of carbonate minerals obtained will be less accurate. Summary of the invention

[0005] The present invention provides a method and system for determining the genesis of carbonate minerals in rocks, so as to solve the problem of low accuracy of isotope analysis in muddy bands of micro-area carbonate rocks and surrounding rocks, and improve the accuracy of micro-area carbonate rock genesis mechanism analysis.

[0006] According to one aspect of the present invention, a method for determining the origin of carbonate minerals in rocks is provided, which is characterized by comprising:

[0007] Obtain rock samples to be analyzed and polish the rock samples;

[0008] Carburizing the polished rock sample, locating the carbonate mineral bands and the mud bands on the carbon-plated rock sample, and determining the position information of the carbonate mineral bands and the position information of the mud bands;

[0009] Based on the position information of the carbonate mineral bands and the position information of the mud bands, isotope detection is performed on the rock samples to obtain isotope detection results, and the formation reasons of the carbonate minerals in the rock samples are determined based on the isotope detection results.

[0010] According to another aspect of the present invention, a detection system for determining the genesis of carbonate minerals in rocks is provided, which is characterized by comprising:

[0011] Polishing machine, which polishes the rock samples to be analyzed;

[0012] Carbon coating equipment, carbon coating of polished rock samples

[0013] Positioning equipment, for positioning carbonate mineral bands and mud bands of carbon-plated rock samples, and determining position information of carbonate mineral bands and mud bands;

[0014] Isotope analysis equipment; based on the position information of carbonate mineral bands and the position information of muddy bands, isotope detection is performed on rock samples to obtain isotope detection results;

[0015] A processor determines the formation cause of carbonate minerals in the rock sample based on the isotope detection results.

[0016] The technical solution of the embodiment of the present invention is to obtain a rock sample to be analyzed, polish the rock sample; perform carbon plating on the polished rock sample, locate the carbonate mineral bands and mud bands of the carbon-plated rock sample, and determine the position information of the carbonate mineral bands and the position information of the mud bands; perform isotope detection on the rock sample based on the position information of the carbonate mineral bands and the position information of the mud bands to obtain the isotope detection results, and determine the formation cause of the carbonate minerals in the rock sample based on the isotope detection results, so as to accurately obtain the positioning of different types of carbonate interlayers and mud interlayers in the rock sample, solve the problem of low accuracy of isotope analysis in mud bands of micro-area carbonate rocks and surrounding rocks, and improve the accuracy of micro-area carbonate rock formation mechanism analysis.

[0017] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 This is a flow chart of a method for determining the origin of carbonate minerals in rocks provided in Example 1 of the present invention;

[0020] Figure 2 It is the carbon-oxygen isotope distribution diagram of two types of carbonate mineral bands and their adjacent mud bands in different rock samples;

[0021] Figure 3 It is the oxygen-strontium isotope distribution diagram of two types of carbonate mineral bands and their adjacent mud bands in different rock samples;

[0022] Figure 4 This is a flow chart of a method for determining the origin of carbonate minerals in rocks provided in Example 2 of the present invention;

[0023] Figure 5 It is a structural schematic diagram of a detection system for determining the origin of carbonate minerals in rocks provided in Example 3 of the present invention. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0025] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0026] Embodiment 1

[0027] Figure 1 This is a flow chart of a method for determining the origin of carbonate minerals in rocks provided by the first embodiment of the present invention. This embodiment is applicable to the prediction of sweet spots and resource evaluation of shale oil and gas resources. The method can be executed by a system for determining the origin of carbonate minerals in rocks, and the system for determining the origin of carbonate minerals in rocks can be implemented in the form of hardware and / or software. Figure 1 As shown, the method includes:

[0028] S110, obtaining a rock sample to be analyzed, and performing a polishing process on the rock sample.

[0029] In this embodiment, the rock samples are samples of rocks collected from a geological exploration area, and each rock sample includes a carbonate mineral band and a mud band.

[0030] Specifically, the rock samples collected from the geological exploration area are screened, and the rock samples including carbonate mineral bands and mud bands are retained as the rock samples to be analyzed. The rock samples are polished using a polisher (for example, an argon ion polisher) to obtain rock samples with smooth and flat surfaces.

[0031] Exemplarily, rock sample a includes only carbonate mineral bands, rock sample b includes only muddy bands, and rock sample c includes both carbonate mineral bands and muddy bands. Rock sample c is used as the rock sample to be analyzed.

[0032] The technical solution of this embodiment is to polish the surface of the rock sample to ensure the flatness of the sample surface and avoid analysis errors caused by the uneven surface of the rock sample in the subsequent analysis process.

[0033] Optionally, an initial rock sample that meets the test conditions is selected, and the initial rock sample is cut based on the processing conditions of the polishing equipment to obtain a rock sample that meets the processing conditions of the polishing equipment.

[0034] In this example, the test condition is that the rock sample includes carbonate mineral bands and mud bands. The initial rock sample is a rock sample that meets the test condition without being polished.

[0035] Specifically, the initial rock sample is finely cut according to the processing conditions of the polishing device to obtain a rock sample of a fixed size to be polished. The processing conditions of the polishing device can be the sample chamber accommodation space conditions of the polishing device, that is, the size of the rock sample is smaller than the accommodation space.

[0036] Exemplarily, the sample chamber of the argon ion polisher used can accommodate samples of up to 2 cm × 2 cm × 1 cm (length × width × height), and the initial rock sample can be cut into 1 cm × 1 cm × 0.6 cm (length × width × height) rock samples to be polished.

[0037] Optionally, the rock sample is continental shale, and the rock sample includes at least one type of carbonate mineral band and muddy band. The rock samples obtained by cutting are screened to remove the rock samples that do not include at least one type of carbonate mineral band and muddy band.

[0038] In this embodiment, the continental shale is a shale in which the development and distribution of carbonate mineral interlayers (or bands) are in the millimeter-micro-nano scale and the crystal types have certain differences.

[0039] Specifically, the rock samples collected from the geological exploration area are screened, and the type of the carbonate mineral band is determined according to the crystal type of each carbonate mineral band, namely, the granular calcite band and the needle-shaped calcite band. Continental shale rock samples having one or more types of carbonate mineral bands and muddy bands are retained.

[0040] Exemplarily, rock sample d is conventional shale including carbonate mineral bands and mud bands, rock sample e is continental shale including only mud bands, rock sample f is continental shale including only carbonate mineral bands, rock sample g is continental shale including one type of carbonate mineral bands and mud bands, and rock sample h is continental shale including multiple types of carbonate mineral bands and mud bands. Rock sample g and rock sample h are used as rock samples to be analyzed.

[0041] The technical solution of this embodiment can ensure the practicality and effectiveness of the technical solution of this embodiment by determining the rock sample as continental shale.

[0042] S120, performing carbon plating on the polished rock sample, locating carbonate mineral bands and mud bands on the carbon plating rock sample, and determining position information of the carbonate mineral bands and the mud bands.

[0043] In this embodiment, the carbon coating treatment is to coat the rock sample with a carbon coating of uniform thickness. The muddy strip is a muddy strip that is adjacent to the carbonate mineral strip.

[0044] Specifically, the polished rock sample is placed in a carbon plating device (e.g., a quartz tube of a carbon-smoked furnace), and carbon plating is performed under a certain air pressure, temperature, and methane introduction rate, so that a uniform carbon coating of a certain thickness is plated on the surface of the polished rock sample. The air pressure, temperature, and methane introduction rate during the carbon plating process are manually determined, and this embodiment does not limit this. The thickness of the carbon coating is set according to the conditions of subsequent experimental analysis. A positioning device is used to locate all types of carbonate mineral bands and their adjacent mud bands in the carbon-plated rock sample, and accurate millimeter-micro-nano scale position information of all types of carbonate mineral bands and their adjacent mud bands is obtained.

[0045] Exemplarily, the polished rock sample is placed in a quartz tube of a carbon-smoked furnace for carbon coating, and a carbon coating with a thickness of 3 nanometers is coated on the surface of the polished rock sample.

[0046] Optionally, the analysis surface of the rock sample is subjected to carbon coating, and the carbon coating thickness of the analysis surface is within a preset thickness threshold range.

[0047] In this embodiment, the analysis surface of the rock sample is one of the multiple surfaces of the rock sample. The preset thickness threshold is the minimum thickness of the carbon coating set according to the conditions of subsequent experimental analysis.

[0048] Specifically, one surface of the rock sample is used as the analysis surface, and the analysis surfaces of all the rock samples are carbon-plated using a carbon plating device, and a carbon coating having a thickness within a preset thickness threshold range is plated on the analysis surfaces of the polished rock samples.

[0049] Exemplarily, the preset thickness threshold range is between 2-4 nanometers, and a carbon coating with a thickness of 3 nanometers is coated on the analysis surface of the polished rock sample.

[0050] S130. Perform isotope detection on the rock sample based on the position information of the carbonate mineral band and the position information of the mud band to obtain an isotope detection result.

[0051] In this embodiment, isotope detection is to use isotope analysis equipment to detect the isotopes of major and trace elements of all types of carbonate mineral bands and their adjacent mud bands in the polished rock sample.

[0052] Specifically, isotope analysis equipment is used to perform isotope detection of major and trace elements on all types of carbonate mineral bands and mud bands of the polished rock samples, respectively, to obtain major and trace element content data of all types of carbonate mineral bands and mud bands.

[0053] Illustratively, based on the position information of all types of carbonate mineral bands in the polished rock sample, a Mat253 stable isotope mass spectrometer is used to perform isotope detection on the materials at the corresponding positions to obtain the carbon-oxygen-strontium isotope content data of the carbonate mineral bands at the corresponding positions; based on the position information of the mud bands adjacent to all types of carbonate mineral bands in the polished rock sample, a Mat253 stable isotope mass spectrometer is used to perform isotope detection on the materials at the corresponding positions to obtain the carbon-oxygen-strontium isotope content data of the mud bands at the corresponding positions.

[0054] Optionally, before performing isotope detection on the rock sample based on the position information of the carbonate mineral bands and the position information of the mud bands, the method further includes: decarbonizing the carbon-plated rock sample.

[0055] In this embodiment, the carbon removal treatment is a treatment for removing all the carbon coating on the surface of the rock sample obtained by carbon plating treatment.

[0056] Specifically, after determining the position information of the carbonate mineral band and the position information of the argillaceous band and before isotope detection, the surface of the rock sample is cleaned and decarbonized. Exemplarily, alcohol can be used to clean and decarbonize the surface of the rock sample.

[0057] The technical solution of this embodiment avoids the occurrence of erroneous isotope content data, which would make the experimental analysis results of the formation mechanism of carbonate rocks unreliable, by removing the carbon coating added by carbon plating.

[0058] Optionally, the isotope detection includes one or more of carbon-oxygen isotope detection and oxygen-strontium isotope detection.

[0059] In this embodiment, carbon-oxygen isotope detection and oxygen-strontium isotope detection are detections of the radioactive carbon, oxygen, and strontium isotope contents in all types of carbonate mineral bands and mud bands, and are suitable for the inversion of climate in geological history, the growth and ablation of continental glaciers, the burial and reoxidation of organic matter, biological productivity, tectonic movements, and changes in ocean circulation.

[0060] Specifically, the isotope analysis equipment can be used to detect the carbon-oxygen isotope content of all types of carbonate mineral bands and mud bands; the isotope analysis equipment can also be used to detect the oxygen-strontium isotope content of all types of carbonate mineral bands and mud bands; the isotope analysis equipment can also be used to detect the carbon-oxygen-strontium isotope content of all types of carbonate mineral bands and mud bands; the isotope analysis equipment can also be used to detect other major-trace isotope contents of all types of carbonate mineral bands and mud bands, and this embodiment does not limit this.

[0061] S140. Determine the formation cause of carbonate minerals in the rock sample based on the isotope detection results.

[0062] In this embodiment, the formation cause of carbonate minerals in the rock sample is deduced based on the isotope content data of each carbonate mineral band and the isotope content data of the adjacent mud band.

[0063] Specifically, if the isotope content data of a carbonate mineral band is similar to the isotope content data of its adjacent mud band, it is believed that the formation of the carbonate minerals in the carbonate mineral band is the common deposition of the mud band adjacent to it, and the calcium in the carbonate is mainly formed by the precipitation of calcium ions in situ; if the isotope content data of a carbonate mineral band is not similar to the isotope content data of its adjacent mud band, it is believed that the formation of the carbonate minerals in the carbonate mineral band is different from that of the adjacent mud band, and the calcium in the carbonate is mainly formed by the precipitation of calcium ions transported from other places.

[0064] For example, Table 1 shows the isotope content data of two types of carbonate mineral bands and their adjacent mud bands of different rock samples. The isotope content data of the granular calcite band is similar to that of the mud band, indicating that the granular calcite was deposited together with the mud band of the surrounding rock during the sedimentation process, and the calcium in the carbonate was mainly formed by the precipitation of calcium ions in situ; while the isotope content data of the needle-columnar calcite band is significantly different from that of the granular calcite band and the mud band, indicating that the formation process of the needle-columnar calcite band is significantly different from that of the granular calcite and the mud band, and the calcium source in the formation process of the needle-columnar calcite band may be more calcium ions migrated from other places.

[0065] Table 1

[0066]

[0067] Optionally, an isotope distribution map is drawn based on the isotope detection results; based on the isotope distribution differences between the carbonate mineral bands and the mud bands in the isotope distribution map, the formation cause of the carbonate minerals is determined.

[0068] In this embodiment, the isotope distribution diagram represents a diagram showing the distribution characteristics of multiple isotope compositions of the same band.

[0069] Specifically, an isotope distribution diagram showing the distribution characteristics of multiple isotope compositions is drawn based on the multiple isotope contents of each type of carbonate mineral band or its adjacent mud band of each rock sample. If the isotope distribution of a certain type of carbonate mineral band in the isotope distribution diagram is slightly different from that of the mud band, it is believed that the formation of the carbonate minerals in the carbonate mineral band is due to the common deposition of the mud band adjacent to it, and the calcium in the carbonate is mainly formed by the precipitation of calcium ions in situ; if the isotope distribution of a certain type of carbonate mineral band in the isotope distribution diagram is significantly different from that of the mud band adjacent to it, it is believed that the formation of the carbonate minerals in the carbonate mineral band is different from that of the mud band adjacent to it, and the calcium in the carbonate is mainly formed by the precipitation of calcium ions transported from other places.

[0070] For example, Figure 2 These are the carbon-oxygen isotope distribution diagrams of two types of carbonate mineral bands and their adjacent mud bands in different rock samples. Figure 3This is the oxygen-strontium isotope distribution diagram of two types of carbonate mineral bands and their adjacent mud bands of different rock samples. It can be seen that the isotope distribution of the granular calcite band is slightly different from the carbon-oxygen and oxygen-strontium isotope distribution of the mud band, indicating that the granular calcite was deposited together with the mud band of the surrounding rock during the sedimentation process, and the calcium in the carbonate was mainly formed by the precipitation of calcium ions in situ; while the isotope distribution of the needle-column calcite band is quite different from the isotope distribution of the granular calcite band and the isotope distribution of the mud band, indicating that the formation process of the needle-column calcite band is significantly different from that of the granular calcite and mud bands, and the calcium source in the formation process of the needle-column calcite band may be more calcium ions migrated from other places.

[0071] The technical solution of this embodiment is to obtain a rock sample to be analyzed, polish the rock sample; perform carbon plating on the polished rock sample, locate the carbonate mineral bands and mud bands of the carbon-plated rock sample, and determine the position information of the carbonate mineral bands and the position information of the mud bands; perform isotope detection on the rock sample based on the position information of the carbonate mineral bands and the position information of the mud bands to obtain the isotope detection results, and determine the formation cause of the carbonate minerals in the rock sample based on the isotope detection results, so as to accurately obtain the location of different types of carbonate interlayers and mud interlayers in the rock sample, solve the problem of low accuracy of isotope analysis in mud bands of micro-area carbonate rocks and surrounding rocks, and improve the accuracy of micro-area carbonate rock formation mechanism analysis.

[0072] Embodiment 2

[0073] Figure 4 This is a flow chart of a method for determining the origin of carbonate minerals in rocks provided by the second embodiment of the present invention. The technical solution of the embodiment of the present invention is further optimized based on any of the above embodiments. Figure 4 As shown, the method includes:

[0074] S210: Obtain a rock sample to be analyzed, and perform a polishing process on the rock sample.

[0075] S220, performing carbon plating on the polished rock sample.

[0076] S230, scanning the analysis surface of the rock sample that has been carbon-plated to determine the distribution of carbonate mineral bands and mudstone bands in the analysis surface.

[0077] Specifically, an electron probe is used to determine the exact distribution of all types of carbonate minerals and their adjacent mud bands on the analysis surface of the rock sample.

[0078] Exemplarily, a rock sample is placed in an electron probe, and the element surface scanning analysis or energy spectrum surface scanning analysis of the electron probe is used to determine the exact distribution state of granular calcite bands, needle-shaped calcite bands and mud bands on the analysis surface of the rock sample.

[0079] The technical solution of this embodiment reduces the subsequent positioning range and improves positioning accuracy by determining the distribution status of carbonate mineral bands and mud bands in the analysis surface.

[0080] S240. Based on the distribution status of the carbonate mineral bands and the mud bands, the carbonate minerals and the mud bands are laser positioned to determine the position information of the carbonate mineral bands and the position information of the mud bands.

[0081] In this embodiment, laser positioning uses a laser beam to locate carbonate mineral bands and muddy bands for subsequent experiments.

[0082] Specifically, according to the distribution status of carbonate mineral bands and their adjacent mud bands, a strong laser beam is used for laser ablation to remove surface materials at each type of carbonate mineral band and its adjacent mud band on the analysis surface of the rock sample, so as to obtain multiple carbonate mineral bands and mud bands inside the exposed rock samples, and the position information of the exposed part on the analysis surface of the rock sample is used as the position information of the corresponding carbonate mineral bands and the position information of the mud bands.

[0083] Exemplarily, a laser beam with certain beam parameters and scanning speed parameters is used to ablate 1 mm of the distribution of carbonate mineral bands and mud bands on the analysis surface of the rock sample to expose the carbonate minerals and mud at a depth of 1 mm, and the position information of the exposed portion of the distribution of each type of carbonate mineral band is used as the position information of that type of carbonate mineral band, and the position information of the exposed portion of the distribution of the mud band is used as the position information of the mud band.

[0084] The technical solution of this embodiment, laser positioning, compared with conventional positioning methods, has the advantages of deep penetration, good directionality and no pollution to the oil layer. It can achieve accurate positioning in the distribution of carbonate mineral bands at the millimeter-micro-nano scale, and avoid the adverse effects of erroneous positioning on subsequent analysis of the cause and mechanism of carbonate rock formation.

[0085] S250. Based on the position information of the carbonate mineral bands and the position information of the mud bands, isotope detection is performed on the rock sample to obtain an isotope detection result.

[0086] S260. Determine the formation cause of carbonate minerals in rock samples based on isotope detection results.

[0087] The technical solution of this embodiment is as follows: by obtaining a rock sample to be analyzed, polishing the rock sample; carbon-plating the polished rock sample, and locating the carbonate mineral bands and mud bands of the carbon-plated rock sample; scanning the analysis surface of the rock sample that has completed the carbon plating to determine the distribution status of the carbonate mineral bands and mud bands in the analysis surface; laser locating the carbonate minerals and mud bands based on the distribution status of the carbonate mineral bands and mud bands to determine the position information of the carbonate mineral bands and the position information of the mud bands; isotope detection of the rock sample based on the position information of the carbonate mineral bands and the position information of the mud bands to obtain the isotope detection results, and determining the formation cause of the carbonate minerals of the rock sample based on the isotope detection results, the positioning of different types of carbonate interlayers and mud interlayers in the rock sample can be accurately obtained, and the isotope content difference of different types of carbonate interlayers can be intuitively reflected, so as to solve the problem of low accuracy of isotope analysis in mud bands of micro-area carbonate rocks and surrounding rocks, and improve the accuracy of micro-area carbonate rock formation mechanism analysis.

[0088] Embodiment 3

[0089] Figure 5 Schematic diagram of a detection system for determining the origin of carbonate minerals in rocks provided by the third embodiment of the present invention. Figure 5 As shown, the system includes:

[0090] A polisher 310 for polishing the rock sample to be analyzed;

[0091] Carbon coating equipment 320, carbon coating of polished rock samples

[0092] Positioning device 330, positioning carbonate mineral bands and mud bands of the carbon-plated rock sample, and determining position information of the carbonate mineral bands and the mud bands;

[0093] The isotope analysis device 340 performs isotope detection on the rock sample based on the position information of the carbonate mineral band and the position information of the mud band to obtain the isotope detection result;

[0094] The processor 350 determines the formation cause of the carbonate minerals in the rock sample based on the isotope detection result.

[0095] The technical solution of this embodiment is to obtain a rock sample to be analyzed, polish the rock sample; perform carbon plating on the polished rock sample, locate the carbonate mineral bands and mud bands of the carbon-plated rock sample, and determine the position information of the carbonate mineral bands and the position information of the mud bands; perform isotope detection on the rock sample based on the position information of the carbonate mineral bands and the position information of the mud bands to obtain the isotope detection results, and determine the formation cause of the carbonate minerals in the rock sample based on the isotope detection results, so as to accurately obtain the location of different types of carbonate interlayers and mud interlayers in the rock sample, solve the problem of low accuracy of isotope analysis in mud bands of micro-area carbonate rocks and surrounding rocks, and improve the accuracy of micro-area carbonate rock formation mechanism analysis.

[0096] On the basis of the above-mentioned embodiment, optionally, the detection system for determining the origin of carbonate minerals in rocks provided in the embodiment of the present invention further includes a cutting device before the polisher 310, which is used to cut the initial style sample to obtain a rock sample that meets the processing conditions of the polishing device.

[0097] Based on the above embodiment, optionally, the positioning device 330 includes an electronic probe and a laser positioning device; the electronic probe scans the carbon-plated rock sample to determine the distribution status of the carbonate mineral bands and the mud bands in the analysis surface; the laser positioning device performs laser positioning on the carbonate minerals and the mud bands based on the distribution status of the carbonate mineral bands and the mud bands to determine the position information of the carbonate mineral bands and the position information of the mud bands.

[0098] The system for determining the genesis of carbonate minerals in rocks provided by the embodiment of the present invention can execute the method for determining the genesis of carbonate minerals in rocks provided by any embodiment of the present invention, and has the functional modules and beneficial effects corresponding to the execution method.

[0099] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0100] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for determining the origin of carbonate minerals in rocks, characterized in that: include: Obtaining a rock sample to be analyzed, and performing a polishing process on the rock sample; Carburizing the polished rock sample, locating the carbonate mineral bands and the mud bands on the carbon-plated rock sample, and determining the position information of the carbonate mineral bands and the position information of the mud bands; Based on the position information of the carbonate mineral band and the position information of the mud band, isotope detection is performed on the rock sample to obtain an isotope detection result, and the formation cause of the carbonate minerals in the rock sample is determined based on the isotope detection result.

2. The method according to claim 1, characterized in that The step of obtaining a rock sample to be analyzed comprises: An initial rock sample that meets the test conditions is selected, and the initial rock sample is cut based on the processing conditions of the polishing equipment to obtain a rock sample that meets the processing conditions of the polishing equipment.

3. The method according to claim 1 or 2, characterized in that: The rock sample is continental shale, and the rock sample includes at least one type of carbonate mineral band and muddy band.

4. The method according to claim 1, characterized in that: The carbon coating treatment of the polished rock sample comprises: The analysis surface of the rock sample is subjected to carbon plating, and the carbon plating thickness of the analysis surface is within a preset thickness threshold range.

5. The method according to claim 1, characterized in that The method of positioning the carbonate mineral bands and the mud bands on the carbon-plated rock sample and determining the position information of the carbonate mineral bands and the mud bands includes: Scanning the carbon-plated analysis surface of the rock sample to determine the distribution of carbonate mineral bands and muddy bands in the analysis surface; Based on the distribution status of the carbonate mineral bands and the mud bands, the carbonate mineral bands and the mud bands are laser positioned to determine the position information of the carbonate mineral bands and the position information of the mud bands.

6. The method according to claim 1, characterized in that Before performing isotope detection on the rock sample based on the position information of the carbonate mineral band and the position information of the mud band, the method further includes: The carbon-plated rock sample is subjected to a decarbonization treatment.

7. The method according to claim 1, characterized in that The isotope detection includes one or more of carbon-oxygen isotope detection and oxygen-strontium isotope detection.

8. The method according to claim 7, characterized in that Determining the formation cause of the carbonate minerals in the rock sample based on the isotope detection result includes: Draw an isotope distribution map based on the isotope detection results; Based on the isotope distribution difference between the carbonate mineral band and the mud band in the isotope distribution diagram, the formation cause of the carbonate mineral is determined.

9. A detection system for determining the origin of carbonate minerals in rocks, characterized in that: include: Polishing machine, which polishes the rock samples to be analyzed; Carbon coating equipment, carbon coating of polished rock samples Positioning equipment, for positioning carbonate mineral bands and mud bands of the carbon-plated rock sample, and determining position information of the carbonate mineral bands and the mud bands; Isotope analysis equipment; Based on the position information of the carbonate mineral band and the position information of the mud band, the rock sample is subjected to isotope detection to obtain an isotope detection result; A processor determines the formation cause of the carbonate minerals in the rock sample based on the isotope detection result.

10. The system according to claim 9, characterized in that The system further comprises: The cutting device is used to cut the initial style sample to obtain a rock sample that meets the processing conditions of the polishing device.

11. The system according to claim 9, characterized in that The positioning device includes an electronic probe and a laser positioning device; The electronic probe scans the carbon-plated rock sample to determine the distribution state of carbonate mineral bands and muddy bands in the analysis surface; The laser positioning device performs laser positioning on the carbonate minerals and the muddy bands based on the distribution states of the carbonate mineral bands and the muddy bands, and determines the position information of the carbonate mineral bands and the position information of the muddy bands.

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