Method for determining the genesis of amorphous material in rock

Abstract

The present application relates to oil and gas exploration technology field, particularly to a kind of amorphous material genesis determination method in rock, on the basis of existing thin section identification analysis method and scanning electron microscopy analysis method, introduce element test and element three end element analysis method, using statistical and element geochemistry View, realize the quantitative analysis of amorphous material genesis in rock, and then analyze rock diagenesis main control factor.Through the determination method, the influence degree of sedimentation and volcanic action can be determined by analyzing the genesis type of amorphous material in rock, and then the main control factor of diagenesis is determined, which can effectively solve the problem of amorphous material genesis identification in rock.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas exploration, and particularly relates to a method for determining the genesis of amorphous matter in rocks. BACKGROUND

[0002] Amorphous matter is an important component in rocks, including amorphous organic matter and amorphous inorganic matter. Common amorphous organic matter in rocks includes kerogen, asphalt and the like, and common amorphous inorganic matter includes volcanic glass, opal, diaspore, limonite and the like, and different types of amorphous matter reflect different rock genesis. According to the theory of oil and gas organic genesis, biological polymers in sediments undergo separation, polymerization and polycondensation under biological and chemical action, and can form geological macromolecules-kerogen under diagenesis, and the kerogen can form oil and gas resources after pyrolysis and cracking, and at the same time, can form soluble organic matter-asphalt, so the content of amorphous kerogen and asphalt is closely related to the formation of oil and gas. Similarly, volcanic glass in amorphous inorganic matter in rocks is a kind of glass structure formed by rapid condensation of lava erupted from a volcano without crystallization, and its content is closely related to volcanic action.

[0003] The Permian stratum is one of important strata for natural gas exploration in the Sichuan Basin, and the stratum is mostly a marine-terrestrial transitional facies depositional system, and the natural gas resources thereof include conventional natural gas, unconventional natural gas (shale gas and coalbed gas), sedimentary rock reservoirs and volcanic rock reservoirs. Among them, the shale gas resources of the Wujiaping Formation of the Permian in the Sichuan Basin exceed 600 billion cubic meters, and the Daye 1H well obtains a high-yield industrial gas flow at the layer, which marks a major discovery of shale gas exploration in the Permian in the Sichuan Basin.

[0004] Due to the Permian strata such as the Longtan Formation in the eastern and southern Sichuan Basin and the Wujiaping Formation in the northern Sichuan Basin, the lithology of the reservoir rocks changes greatly in the vertical direction, the mineral composition changes greatly, the heterogeneity is extremely strong, and the rock components are extremely complex, containing both volcanic matter and sedimentary matter, which makes it extremely difficult to analyze the diagenesis and evolution mechanism, and also brings great challenges to the evaluation of the natural gas exploration potential and the next exploration work in the block.

[0005] The existing rock amorphous material analysis mainly relies on polarizing microscope, and uses thin section identification method to identify. Taking two typical amorphous materials, volcanic glass formed by volcanic action and asphalt (organic matter) formed by sedimentation as examples, the composition particles are not crystallized or isotropic, and both of them are amorphous bodies, so there is no obvious optical property under orthogonal polarization, but there is still some difference between the optical property and structure of the two under single polarization. The volcanic glass has certain optical property under single polarization, and the color and texture change characteristics can be observed, but it has no optical property under orthogonal polarization. The asphalt has no optical property under single polarization and orthogonal polarization because its color is black. Since the non-crystal volcanic glass will gradually transform into crystal during geological evolution and form devitrification structure, the glassy structure often coexists with the devitrification structure, so the existence of the volcanic glass can be identified according to different devitrification structures. For the asphalt, it is often distributed in the rock pores, cracks and other structures because it is related to oil and gas migration, so it can be identified according to the spatial position distribution characteristics. However, when the volcanic glass and the asphalt coexist and the content is relatively high, especially when they are interlaced and mixed, because both of them have no optical property under the polarizing microscope, the content of the two cannot be identified by the polarizing microscope, and the influence degree of the volcanic action and the sedimentation cannot be analyzed. SUMMARY

[0006] To solve the above technical problems, the present application provides a method for determining the genesis of amorphous material in rock, which can determine the influence degree of sedimentation and volcanic action by analyzing the content of different types of amorphous material in rock, so as to determine the main controlling factor of diagenesis, and finally determine the main geological action affecting the formation of amorphous material in rock, and realize the quantitative analysis of the genesis.

[0007] The present application is realized by adopting the following technical solutions:

[0008] A method for determining the genesis of amorphous material in rock, comprising the following steps:

[0009] Step S1. Selecting a rock sample, and preparing the sample into a rock powder, a rock thin section and a sub-ion polished section;

[0010] Step S2. Performing X-ray diffraction analysis on the rock powder sample to determine the content of amorphous material therein, and then performing carbon and sulfur analysis to determine the content of organic carbon therein; when the determined content of amorphous material and the content of organic carbon are negatively correlated, it indicates that the amorphous component is mainly non-crystal inorganic matter, and it is determined that the amorphous material is mainly caused by volcanic action; when the determined content of amorphous material and the content of organic carbon are positively correlated or have no correlation, the rock thin section in step S1 is analyzed and identified to determine whether organic matter and volcanic glass exist in the rock thin section at the same time, and if so, step S3 is entered;

[0011] Step S3. The electron probe method is used to perform carbon, silicon, aluminum, and iron four-element area scanning tests on the area in the rock thin section in step S2 that simultaneously contains organic matter and volcanic glass, to obtain element area scanning maps and the corresponding percentage contents of the four elements of carbon, silicon, aluminum, and iron, and determine whether the area simultaneously contains the four elements of carbon, silicon, aluminum, and iron.

[0012] Step S4. The scanning electron microscope method is used to identify the sub-ion polished section in step S1, and the area of the amorphous material that simultaneously contains volcanic glass and organic matter is determined according to the special morphological structure of the volcanic glass and the organic matter.

[0013] Step S5. The energy spectrometer is used to perform carbon, silicon, aluminum, and iron four-element area scanning tests on the area in step S4, to obtain element area scanning maps and the corresponding percentage contents of the four elements of carbon, silicon, aluminum, and iron, and determine whether the area simultaneously contains the four elements of carbon, silicon, aluminum, and iron.

[0014] Step S6. The percentage contents of the carbon element, the silicon element, and the aluminum+iron element are taken as three end members to form a triangular diagram, and the percentage contents of each element obtained in steps S3 and S5 are plotted in the form of scattered points on the triangular diagram to form a three-end-member element distribution diagram.

[0015] Step S7. The element distribution characteristics of the three-end-member element distribution diagram are used to identify the genesis of the amorphous material in the rock.

[0016] In step S7, identifying the genesis of the amorphous material in the rock specifically refers to: in the three-end-member element distribution diagram, if the number of scattered points of the carbon end member is more than that of the silicon end member and the aluminum-iron end member, it is determined that the amorphous material is mainly of sedimentary origin; if the number of scattered points of the silicon end member is more than that of the carbon end member and the aluminum-iron end member, it is determined that the amorphous material is of both sedimentary origin and volcanic origin; and if the number of scattered points of the aluminum-iron end member is more than that of the carbon end member and the silicon end member, it is determined that the amorphous material is mainly of volcanic origin.

[0017] If the number of scattered points of the silicon end member is large, the spatial position distribution of the carbon element and the silicon element in the element area scanning map obtained in steps S3 and S5 is determined, and if the spatial position distribution of the carbon element and the silicon element is completely consistent, it is determined that the amorphous material is mainly of sedimentary origin; if the spatial position distribution of the carbon element and the silicon element is completely inconsistent, it is determined that the amorphous material is mainly of volcanic origin; and if the spatial position distribution of the carbon element and the silicon element is not completely consistent, it is determined that the amorphous material is affected by both volcanic action and sedimentary action.

[0018] It also includes determining a plurality of areas of amorphous material that simultaneously contains volcanic glass and organic matter.

[0019] The number of finally determined areas of amorphous material that simultaneously contains volcanic glass and organic matter is at least 10.

[0020] The step S2 of analyzing and identifying the rock slice specifically refers to: using a polarizing microscope, under a single polariscope, to analyze and identify the rock slice.

[0021] The special morphological structure of the volcanic glass and the organic matter in the step S4 specifically refers to: the volcanic glass has a gel body structure, and the organic matter has a biological structure.

[0022] The triangle graph in the step S6 is an equilateral triangle graph.

[0023] The thickness of the rock slice is not more than 0.035 mm, and the thickness of the sub-ion polishing slice is not more than 5 mm.

[0024] Compared with the prior art, the beneficial effects of the present application are as follows:

[0025] 1. On the basis of the existing slice identification and analysis method and the scanning electron microscope analysis method, the present application introduces element testing and element three-end element analysis method, uses statistical and element geochemical points of view, realizes the quantitative analysis of the causes of amorphous substances in rocks, and further analyzes the main controlling factors of rock diagenesis, solves the problem that single slice identification or scanning identification method cannot analyze the causes of amorphous substances, and can meet the research needs of reservoir rock diagenesis in the marine-continental transitional facies and shallow marine facies sedimentary system which is affected by both volcanic action and sedimentation.

[0026] 2. The present application solves the technical problem that it is difficult to identify the content of organic amorphous substances and inorganic amorphous substances in the process of rock slice identification due to their similar optical properties and deep color, and overcomes the technical bottleneck that it is difficult to characterize the occurrence state of organic amorphous substances and inorganic amorphous substances due to their mutual intermingling.

[0027] 3. The present application proposes to determine the main types of amorphous substances by X-ray diffraction and carbon-sulfur analysis, effectively combines two analysis methods of material composition and element composition, realizes the rapid identification of the types of amorphous substances in rocks, and has important guiding significance for rock diagenesis research.

[0028] 4. The present application proposes to use electron probe and sub-ion polishing scanning electron microscope two kinds of microscopic positioning methods, which can effectively determine the area of spectral element surface scanning according to the special morphological structure of volcanic glass and organic matter and the judgment of whether containing carbon, silicon, aluminum and iron four elements, and the resolution and accuracy of the analysis area determined by the single rock slice identification method are higher, which effectively overcomes the problem that it is difficult to find a suitable analysis area due to the limitation of the maximum resolution of the polarizing microscope, and is especially suitable for analyzing rocks composed of micron and nanometer particles such as shale and tight sandstone.

[0029] 5、The application uses the statistical point of view, and innovatively proposes a method for identifying the genesis of non-crystalline matter in rocks by using the three-end element distribution law of material elements.

[0030] 6、The application realizes quantitative characterization of the genesis of non-crystalline matter in rocks by establishing a three-end element analysis method, and can analyze the influence degree of volcanic action and sedimentation by determining the three-end element distribution law, thereby providing a strong basis for analyzing the rock-forming mechanism and providing strong data support for regional geological research of the epeiric and neritic sedimentary systems.

[0031] 7、The application can realize the source and genesis analysis of silicon elements by analyzing the element spatial distribution characteristics according to the characteristics that organic silicon has Si-C bonds and inorganic silicon has Si-O bonds, and can further analyze the genesis of non-crystalline matter in rocks by analyzing the source of silicon elements, and the method is based on the element geochemistry theory and can reflect the geological action law in a deep level. BRIEF DESCRIPTION OF DRAWINGS

[0032] The application will be further described in detail below in combination with the drawings and specific embodiments.

[0033] Figure 1 FIG. 1 is a schematic diagram of the three-end element distribution in the application. DETAILED DESCRIPTION

[0034] Embodiment 1

[0035] As the basic embodiment of the application, the application includes a method for determining the genesis of non-crystalline matter in rocks, which includes the following steps:

[0036] Step S1. Selecting a rock sample, and preparing the sample into a rock powder, a rock thin section and an ion polishing section.

[0037] Step S2. Performing X-ray diffraction analysis on the rock powder sample to determine the non-crystalline content therein, and then performing carbon-sulfur analysis to determine the organic carbon content therein. When the determined non-crystalline content and the organic carbon content are negatively correlated, it indicates that the non-crystalline composition is mainly non-crystalline inorganic matter, and it is determined that the non-crystalline matter is mainly of volcanic action. When the determined non-crystalline content and the organic carbon content are positively correlated or have no correlation, the rock thin section in step S1 is analyzed and identified to determine whether organic matter and volcanic glass exist in the rock thin section at the same time, and if so, step S3 is entered.

[0038] Step S3. Using electron probe method, the area of rock thin section in step S2 which contains organic matter and volcanic glass simultaneously is tested by carbon, silicon, aluminum and iron four elements area scanning, to obtain element area scanning and corresponding carbon, silicon, aluminum and iron four elements percentage content, to determine whether the area contains carbon, silicon, aluminum and iron four elements simultaneously.

[0039] Step S4. Using scanning electron microscope method, the sub-ion polished section in step S1 is identified, and the area of amorphous material containing volcanic glass and organic matter is determined according to the special morphology structure of volcanic glass and organic matter.

[0040] Step S5. Using energy spectrometer, the area in step S4 is tested by carbon, silicon, aluminum and iron four elements area scanning, to obtain element area scanning and corresponding carbon, silicon, aluminum and iron four elements percentage content, to determine whether the area contains carbon, silicon, aluminum and iron four elements simultaneously.

[0041] Step S6. Taking carbon element, silicon element and aluminum+iron element percentage content as three end elements to make a triangular diagram, and the element percentage content obtained in step S3 and step S5 is scattered in the triangular diagram to form a three end element distribution diagram.

[0042] Step S7. Using the element distribution characteristics of the three end element distribution diagram, the genesis of the amorphous material in the rock is identified.

[0043] The embodiment realizes the quantitative analysis of the genesis of the amorphous material in the rock by using the statistical and element geochemical points of view, and further assists the analysis of the main controlling factors of rock diagenesis, to provide strong data support for the exploration and development decision-making work such as reservoir geological evaluation.

[0044] Embodiment 2

[0045] As a preferred embodiment of the present application, the present application comprises a method for determining the genesis of amorphous material in rock, comprising the following steps:

[0046] Step S1. Selecting a rock sample, and preparing the sample into a rock powder, a rock thin section and a sub-ion polished section.

[0047] Step S2. The rock powder sample is analyzed by X-ray diffraction to determine the amorphous content; then carbon and sulfur analysis is performed to determine the organic carbon content. When the determined amorphous content and organic carbon content are negatively correlated, it indicates that the amorphous component is mainly non-crystalline inorganic matter, and it is determined that the amorphous matter is mainly of volcanic origin. When the determined amorphous content and organic carbon content are positively correlated or have no correlation, the rock thin section in step S1 is analyzed and identified to determine whether organic matter and volcanic glass exist simultaneously in the rock thin section, and if so, step S3 is entered.

[0048] Step S3. Using electron probe method, the area of rock thin section in step S2 which contains both organic matter and volcanic glass is tested by carbon, silicon, aluminum, iron four elements area scanning, and the element area scanning and the corresponding percentage content of carbon, silicon, aluminum, iron four elements are obtained to determine whether the area contains carbon, silicon, aluminum and iron four elements.

[0049] Step S4. Using scanning electron microscope method, the sub-ion polished section prepared in step S1 is identified, and the area of amorphous material containing both volcanic glass and organic matter is determined according to the special morphology structure of volcanic glass and organic matter. Repeat the above steps to determine multiple areas of amorphous material containing both volcanic glass and organic matter. The number of finally determined areas of amorphous material containing both volcanic glass and organic matter is at least 10.

[0050] Step S5. Using energy spectrometer, the area in step S4 is tested by carbon, silicon, aluminum, iron four elements area scanning, and the element area scanning and the corresponding percentage content of carbon, silicon, aluminum, iron four elements are obtained to determine whether the area contains carbon, silicon, aluminum and iron four elements.

[0051] Step S6. Taking the percentage content of carbon element, silicon element and aluminum+iron element as three end elements to make a triangular diagram, and the element percentage content obtained in step S3 and step S5 is scattered in the triangular diagram to form a three end element distribution diagram.

[0052] Step S7. Using the element distribution characteristics of the three end element distribution diagram, the genesis of the amorphous material in the rock is identified. In the three end element distribution diagram, if the number of scattered points of carbon end element is more than that of silicon end element and aluminum iron end element, it is judged that the amorphous material is mainly formed by sedimentation; if the number of scattered points of silicon end element is more than that of carbon end element and aluminum iron end element, it is judged that the genesis of the amorphous material is affected by both sedimentation and volcanic action; if the number of scattered points of aluminum iron end element is more than that of carbon end element and silicon end element, it is judged that the amorphous material is mainly formed by volcanic action.

[0053] Example 3

[0054] As another preferred embodiment of the present application, the present application comprises a method for determining the genesis of amorphous material in rock, comprising the following steps:

[0055] S1. Select a rock sample, and prepare the sample into rock powder, rock thin section and sub-ion polished section. The thickness of the rock thin section is not more than 0.035mm, and the thickness of the sub-ion polished section is not more than 5mm.

[0056] Step S2. The rock powder sample is subjected to X-ray diffraction analysis to determine the amorphous content. Carbon and sulfur analysis is then performed to determine the organic carbon content. When the measured amorphous content is negatively correlated with the organic carbon content, it indicates that the amorphous component is mainly amorphous inorganic matter, and it is determined that the amorphous matter is mainly of volcanic origin. When the measured amorphous content is positively correlated or not correlated with the organic carbon content, the rock thin section in step S1 is analyzed and identified under a single polariscope using a polarizing microscope to determine whether organic matter and volcanic glass exist simultaneously in the rock thin section. If so, proceed to step S3.

[0057] Step S3. The area where organic matter and volcanic glass exist simultaneously in the rock thin section in step S2 is subjected to carbon, silicon, aluminum, and iron element face scanning tests using an electron probe method to obtain element face scanning maps and the corresponding percentage contents of carbon, silicon, aluminum, and iron elements to determine whether the area contains carbon, silicon, aluminum, and iron elements simultaneously.

[0058] Step S4. The sub-ion polished section prepared in step S1 is identified using a scanning electron microscope method to determine the area of amorphous matter containing volcanic glass and organic matter based on the special morphological structure of volcanic glass and organic matter.

[0059] Step S5. The area in step S4 is subjected to carbon, silicon, aluminum, and iron element face scanning tests using an energy spectrometer to obtain element face scanning maps and the corresponding percentage contents of carbon, silicon, aluminum, and iron elements to determine whether the area contains carbon, silicon, aluminum, and iron elements simultaneously.

[0060] Step S6. The percentage contents of carbon, silicon, and aluminum + iron elements are used as three end members to make a triangular diagram, and the element percentage contents obtained in steps S3 and S5 are plotted in the form of scattered points on the triangular diagram to form a three-end element distribution diagram.

[0061] Step S7. The element distribution characteristics of the three-end element distribution diagram are used to identify the origin of the amorphous matter in the rock. In the three-end element distribution diagram, if the scattered points of the carbon end member are more than those of the silicon end member and the aluminum-iron end member, it is determined that the amorphous matter is mainly of sedimentary origin. If the scattered points of the silicon end member are more than those of the carbon end member and the aluminum-iron end member, it is determined that the amorphous matter is influenced by both sedimentation and volcanism. If the scattered points of the aluminum-iron end member are more than those of the carbon end member and the silicon end member, it is determined that the amorphous matter is mainly of volcanic origin.

[0062] Example 4

[0063] As the best embodiment of the present application, the present application includes a method for determining the origin of amorphous matter in rocks, comprising the following steps:

[0064] Step S1. Select a rock sample, and make the sample into a rock powder, a rock thin section and a sub-ion polished section respectively. The thickness of the rock thin section should meet the technical requirements of "Rock Section Making Method: SY / T 5913-2004", and in principle, the thickness is not greater than 0.035 mm. The thickness of the sub-ion polished section should meet the technical requirements of "Rock Sample Scanning Electron Microscope Analysis Method: SY / T 5162-2021", and in principle, the thickness is not greater than 5 mm.

[0065] Step S2. Perform X-ray diffraction analysis on the rock powder sample to determine the amorphous content thereof, and then perform carbon and sulfur analysis to determine the organic carbon content thereof. When the amorphous content and the organic carbon content are negatively correlated, it indicates that the amorphous component is mainly non-crystalline inorganic matter, and it is determined that the amorphous matter is mainly of volcanic origin.

[0066] When the amorphous content and the organic carbon content are positively correlated or have no correlation, the rock thin section in step S1 is analyzed and identified by a rock thin section identification method. Specifically, the rock thin section is analyzed and identified under a single polariscope by using a polarizing microscope. It is determined whether organic matter and volcanic glass exist in the rock thin section at the same time. If yes, step S3 is entered, and if no, the process is directly ended.

[0067] The rock thin section identification method meets the technical requirements of "Rock Thin Section Identification: SY / T 5368-2016". Volcanic glass has certain optical properties under single polarization, and most of them can be observed for color and texture change characteristics, but under orthogonal polarization, they have no optical properties. Organic matter is black in color, and has no optical properties under single polarization and orthogonal polarization.

[0068] Step S3. The electron probe method is used to perform carbon, silicon, aluminum and iron element area scanning tests on the region where organic matter and volcanic glass exist at the same time in the rock thin section in step S2, to obtain element area scanning maps and corresponding carbon, silicon, aluminum and iron element contents, and to determine whether the region contains carbon, silicon, aluminum and iron elements at the same time.

[0069] Step S4. The scanning electron microscope method is used to identify the sub-ion polished section made in step S1, and the regions of amorphous matter containing volcanic glass and organic matter at the same time are determined according to the special morphological structures of volcanic glass and organic matter. The above steps are repeated to determine at least 10 regions of amorphous matter containing volcanic glass and organic matter at the same time.

[0070] Further, the rock scanning electron microscope method meets the technical requirements of "Rock Sample Scanning Electron Microscope Analysis Method: SY / T 5162-2021", and the special morphological structures of volcanic glass and organic matter specifically refer to the fact that the volcanic glass has a certain gel body structure, and the organic matter has a certain biological structure.

[0071] Step S5. Use the energy spectrometer to test the area in step S4 for carbon, silicon, aluminum, and iron element surface scanning, obtain the element surface scanning map and its corresponding carbon, silicon, aluminum, and iron element percentage content, and determine whether the area contains carbon, silicon, aluminum, and iron four elements at the same time.

[0072] Further, the energy spectrum analysis method should meet the technical requirements of the "Rock and Mineral Energy Spectrum Quantitative Analysis Method: SY / T 6189-2018".

[0073] Step S6. Refer to the attached Figure 1 , take the percentage contents of carbon element, silicon element, and aluminum+iron element as three end elements to make a triangular diagram, and put the element percentage contents obtained in steps S3 and S5 in the form of scattered points in the triangular diagram to form a three-end element distribution diagram.

[0074] Step S7. Use the element distribution characteristics of the three-end element distribution diagram to identify the genesis of the amorphous material in the rock: in the three-end element distribution diagram, if the scattered points of the carbon end element are more than those of the silicon end element and the aluminum-iron end element, it is judged that the amorphous material is mainly formed by sedimentation; if the scattered points of the silicon end element are more than those of the carbon end element and the aluminum-iron end element, it is judged that the amorphous material is formed by both sedimentation and volcanic action; if the scattered points of the aluminum-iron end element are more than those of the carbon end element and the silicon end element, it is judged that the amorphous material is mainly formed by volcanic action.

[0075] Further, if the silicon end element scattered points are more, combine the element surface scanning maps in steps S3 and S5 to judge whether the spatial position distribution of the carbon element and the silicon element in the element surface scanning map is consistent; if the distribution positions of the carbon element and the silicon element are completely consistent, it is judged that the amorphous material is mainly formed by sedimentation; if the distribution positions of the carbon element and the silicon element are completely inconsistent, it is judged that the amorphous material is mainly formed by volcanic action; if the distribution positions of the carbon element and the silicon element are not completely consistent, it is judged that the amorphous material is affected by both volcanic action and sedimentation.

[0076] In summary, after reading the present application document, the ordinary skilled in the art can make various corresponding transformation schemes according to the technical solutions and technical concepts of the present application without creative mental effort, which all belong to the scope protected by the present application.

Claims

1. A method for determining the origin of amorphous material in rock, characterized by: The method comprises the following steps: Step S1. Selecting a rock sample, and preparing the sample into a rock powder, a rock slice and a sub-ion polished slice respectively; Step S2. Performing X-ray diffraction analysis on the rock powder sample to determine the amorphous content thereof, and then performing carbon-sulfur analysis to determine the organic carbon content thereof; When the determined amorphous content and the organic carbon content are negatively correlated, it is indicated that the amorphous component is mainly non-crystalline inorganic matter, and it is determined that the amorphous matter is mainly of volcanic origin; When the determined amorphous content and the organic carbon content are positively correlated or have no correlation, the rock slice in step S1 is analyzed and identified to determine whether organic matter and volcanic glass exist simultaneously in the rock slice, and if so, step S3 is entered; Step S3. Using an electron probe method, carbon, silicon, aluminum and iron four-element area scanning tests are performed on the region in which the rock slice in step S2 simultaneously contains organic matter and volcanic glass to obtain element area scanning maps and the corresponding percentage contents of carbon, silicon, aluminum and iron four elements, and it is determined whether the region simultaneously contains carbon, silicon, aluminum and iron four elements; Step S4. Using a scanning electron microscope method, the sub-ion polished slice in step S1 is identified, and the region of the amorphous matter containing volcanic glass and organic matter is determined according to the special morphological structure of the volcanic glass and the organic matter; Step S5. Using an energy spectrometer, carbon, silicon, aluminum and iron four-element area scanning tests are performed on the region in step S4 to obtain element area scanning maps and the corresponding percentage contents of carbon, silicon, aluminum and iron four elements, and it is determined whether the region simultaneously contains carbon, silicon, aluminum and iron four elements; Step S6. Taking the percentage contents of carbon element, silicon element and aluminum+iron element as three vertices to draw a triangular diagram, and the percentage contents of each element obtained in steps S3 and S5 are plotted in the form of scattered points on the triangular diagram to form a three-vertex element distribution diagram; Step S7. Using the element distribution characteristics of the three-vertex element distribution diagram, the origin of the amorphous matter in the rock is identified.

2. The method according to claim 1, characterized in that: In step S7, identifying the origin of the amorphous matter in the rock specifically refers to: in the three-vertex element distribution diagram, if the scattered points of the carbon vertex are more than those of the silicon vertex and the aluminum-iron vertex, it is determined that the amorphous matter is mainly of sedimentary origin, if the scattered points of the silicon vertex are more than those of the carbon vertex and the aluminum-iron vertex, it is determined that the origin of the amorphous matter is affected by both sedimentation and volcanism, and if the scattered points of the aluminum-iron vertex are more than those of the carbon vertex and the silicon vertex, it is determined that the amorphous matter is mainly of volcanic origin. If the silicon vertex has more scattered points, the spatial position distribution of the carbon element and the silicon element in the element area scanning map in steps S3 and S5 is determined, if the carbon element and the silicon element are completely consistent in distribution position, it is determined that the amorphous matter is mainly of sedimentary origin, if the carbon element and the silicon element are completely inconsistent in distribution position, it is determined that the amorphous matter is mainly of volcanic origin, and if the carbon element and the silicon element are not completely consistent in distribution position, it is determined that the amorphous matter is affected by both volcanism and sedimentation.

3. The method according to claim 2, wherein: Further comprising determining multiple regions of the amorphous matter containing volcanic glass and organic matter.

4. The method according to claim 2 or 3, characterized in that: ​ 5. The method of claim 4, wherein: The number of the finally determined areas of the amorphous substance containing the volcanic glass and the organic matter is at least 10.

6. The method of claim 2, wherein: The analyzing and identifying the rock slice in the step S2 specifically refers to: using a polarizing microscope, under a single polariscope, to analyze and identify the rock slice.

7. The method for determining the origin of amorphous material in rock according to claim 3, characterized in that: The special morphological structure of the volcanic glass and the organic matter in the step S4 specifically refers to: the volcanic glass has a gel body structure, and the organic matter has a biological structure.

8. The method of claim 2, wherein: The triangle graph in the step S6 is an equilateral triangle graph. ​ 9. The method of claim 2, wherein: The thickness of the rock slice is not more than 0.035 mm, and the thickness of the sub-ion polishing sheet is not more than 5 mm. ​

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