Method of determining the origin of sandstone

Abstract

Embodiments of the present application relate to the field of testing or analyzing materials by means of determining chemical or physical properties of the materials, and particularly relate to a method for determining the provenance of sandstone, comprising: obtaining a sandstone sample to be determined and a control sample with known provenance, determining the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer of the sandstone sample and the control sample; determining the chemical weathering index of the sandstone sample and the control sample; determining the ratio of the contents of SiO2 and Al2O3 of the sandstone sample and the control sample; determining a provenance-related classification function; and determining the provenance of the sandstone sample according to the classification function, the chemical weathering index, the ratio of the contents of SiO2 and Al2O3, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer of the control sample and the sandstone sample. The method provided by the embodiments of the present application can effectively and accurately determine the provenance of the sandstone sample to be determined.

Description

Technical Field

[0001] Embodiments of this application relate to the field of testing or analyzing materials by measuring their chemical or physical properties, and specifically to a method for determining the origin of sandstone. Background Technology

[0002] The statements herein are provided merely as background information in connection with this application and do not necessarily constitute prior art.

[0003] Sandstone, a common sedimentary rock, is widely distributed across the Earth's surface, and its occurrence is closely related to geological history and sedimentary environments. Determining sandstone deposits is beneficial for reconstructing paleogeographic environments, the evolutionary history of sedimentary basins, and tectonic processes. Sandstone typically contains important mineral resources such as uranium and copper; therefore, determining sandstone deposits also helps in identifying the distribution patterns of these mineral resources. Thus, it is necessary to study the techniques for determining sandstone deposits.

[0004] Currently, there are still many limitations in the technology for determining the origin of sandstone. Summary of the Invention

[0005] A brief overview of this application is provided below to offer a basic understanding of certain aspects thereof. It should be understood that this overview is not an exhaustive summary of the application. It is not intended to identify key or essential parts of the application, nor is it intended to limit its scope. Its purpose is merely to present certain concepts in a simplified form as a prelude to the more detailed description that follows.

[0006] To address the aforementioned issues, embodiments of this application provide a method for determining the origin of sandstone.

[0007] The method includes the following steps: S10, obtaining multiple sandstone samples from unknown origins; S20, preparing multiple sandstone samples into multiple sandstone samples of a first grain size and multiple sandstone samples of a second grain size, wherein the first grain size is larger than the second grain size; S30, determining the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple sandstone samples of the first grain size; S40, determining the contents of SiO2, K2O, Na2O, CaO, and Al2O3 in the multiple sandstone samples of the second grain size; S50, based on the contents of SiO2, K2O, Na2O, CaO, and Al2O3 in the multiple sandstone samples of the second grain size determined in step S40, determining the chemical weathering index and the ratio of SiO2 content to Al2O3 content of the multiple sandstone samples of the second grain size; S60, obtaining multiple control samples from known origins, and performing steps S20-S50 on the multiple control samples; S70, based on... The origin of multiple control samples, their chemical weathering indices, the ratio of SiO2 to Al2O3 content, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the control samples were used to determine multiple classification functions related to the sandstone's origin; S80, based on the multiple classification functions determined in step S70, the chemical weathering indices of the multiple control samples, and the SiO2 content of the multiple control samples... The origin of multiple sandstone samples was determined by the ratio of SiO2 content to Al2O3 content, the ratio of SiO2 content to Al2O3 content in multiple sandstone samples, the chemical weathering index of multiple sandstone samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple control samples and multiple sandstone samples.

[0008] The method provided in this application determines a classification function related to the origin of sandstone by determining the chemical weathering index of the control sample, the ratio of SiO2 content to Al2O3 content of the control sample, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the control sample. This allows for the effective determination of the origin of a sandstone sample based on the location-related classification function, the chemical weathering index of the sandstone sample, the ratio of SiO2 content to Al2O3 content of the sandstone sample, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the sandstone sample. Furthermore, it reduces the complexity of determining the origin of a sandstone sample, improves the determination efficiency, and enhances the determination of... This method improves the accuracy of sandstone sample provenance, thus providing reliable and accurate technical support for geological research and resource exploration. Furthermore, by preparing the sandstone samples and control samples into first- and second-grained samples, the processing work can be minimized, reducing intermediate steps and the likelihood of contamination. This facilitates accurate measurement of the aforementioned contents and chemical weathering index. Additionally, preparing the sandstone samples and control samples into first- and second-grained samples makes it easier to measure the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, illite / montmorillonite mixed layers, as well as the contents of SiO2, K2O, Na2O, CaO, and Al2O3 in the samples. Attached Figure Description

[0009] Other objects and advantages of this application will become apparent from the following description of embodiments of this application with reference to the accompanying drawings, and will help to provide a comprehensive understanding of this application.

[0010] Figure 1 This is a flowchart illustrating the method provided in an embodiment of this application.

[0011] Figure 2 It is based on Figure 1 The diagram shows the relationship between the origin of the control sample and the relative distance between the control samples, as determined by the method.

[0012] It should be noted that the accompanying drawings are not necessarily drawn to scale, but are shown only in a schematic manner without affecting the reader's understanding. Detailed Implementation

[0013] Exemplary embodiments of this application will be described below with reference to the accompanying drawings. For clarity and brevity, not all features of actual implementations are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the development of any such actual embodiment to achieve the developer's specific goals, such as complying with constraints related to the system and business, and these constraints may vary depending on the implementation. Furthermore, it should be understood that while development work can be very complex and time-consuming, such development work is merely a routine task for those skilled in the art who benefit from the content of this application.

[0014] It should also be noted that, in order to avoid obscuring this application with unnecessary details, only the equipment structure and / or processing steps closely related to the solution according to this application are shown in the accompanying drawings, while other details that are not closely related to this application are omitted.

[0015] In related technologies, the chemical and mineral composition of sandstone is used to determine the origin of sandstone. However, the chemical and mineral composition of sandstone cannot fully reflect the characteristics of different sandstone origins, resulting in problems such as ineffective determination and low accuracy in determining the origin of sandstone.

[0016] To address the aforementioned issues, embodiments of this application provide a method for determining the origin of sandstone.

[0017] See Figure 1 , Figure 1This is a flowchart of a method provided in an embodiment of this application. The method may include the following steps: S10, obtaining multiple sandstone samples with unknown origins; S20, preparing multiple sandstone samples into multiple sandstone samples of a first grain size and multiple sandstone samples of a second grain size, wherein the first grain size is larger than the second grain size; S30, determining the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple sandstone samples of the first grain size; S40, determining the contents of SiO2, K2O, Na2O, CaO, and Al2O3 in the multiple sandstone samples of the second grain size; S50, determining the chemical weathering index and the ratio of SiO2 content to Al2O3 content of the multiple sandstone samples of the second grain size based on the contents of SiO2, K2O, Na2O, CaO, and Al2O3 determined in step S40; S60, obtaining multiple control samples with known origins, and performing steps S20-S5 on the multiple control samples. Step 0; S70, Based on the origin of multiple control samples, the chemical weathering index of multiple control samples, the ratio of SiO2 content to Al2O3 content of multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple control samples, determine multiple classification functions related to the origin of sandstone; S80, Based on the multiple classification functions determined in step S70, the chemical weathering index of multiple control samples, and the SiO2 content to Al2O3 content of multiple control samples, determine multiple classification functions related to the origin of sandstone; The origin of multiple sandstone samples was determined by the ratio of iO2 content to Al2O3 content, the ratio of SiO2 content to Al2O3 content in multiple sandstone samples, the chemical weathering index of multiple sandstone samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple control samples and multiple sandstone samples.

[0018] The method provided in this application determines a classification function related to the origin of sandstone by determining the chemical weathering index of the control sample, the ratio of SiO2 content to Al2O3 content of the control sample, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the control sample. This allows for the effective determination of the origin of a sandstone sample based on the location-related classification function, the chemical weathering index of the sandstone sample, the ratio of SiO2 content to Al2O3 content of the sandstone sample, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the sandstone sample. Furthermore, it reduces the complexity of determining the origin of a sandstone sample, improves the determination efficiency, and enhances the determination of... This method improves the accuracy of sandstone sample provenance, thus providing reliable and accurate technical support for geological research and resource exploration. Furthermore, by preparing the sandstone samples and control samples into first- and second-grained samples, the processing work can be minimized, reducing intermediate steps and the likelihood of contamination. This facilitates accurate measurement of the aforementioned contents and chemical weathering index. Additionally, preparing the sandstone samples and control samples into first- and second-grained samples makes it easier to measure the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, illite / montmorillonite mixed layers, as well as the contents of SiO2, K2O, Na2O, CaO, and Al2O3 in the samples.

[0019] In some embodiments, the first particle size can be 60 to 80 mesh to facilitate the measurement of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in samples with the first particle size. For example, the first particle size can be 70 mesh.

[0020] In some embodiments, the second particle size can be 200 mesh to facilitate the measurement of the SiO2, K2O, Na2O, CaO and Al2O3 content in the sample with the second particle size.

[0021] In some embodiments, in step S20, each sandstone sample may be processed to make a sandstone sample of a first grain size and a sandstone sample of a second grain size, i.e., the number of sandstone samples of the first grain size and the number of sandstone samples of the second grain size are the same as the number of sandstone samples obtained; in step S60, the obtained control sample is processed in the same way.

[0022] In some embodiments, in step S60, when obtaining multiple control samples, at least three control samples are obtained from each origin. In such embodiments, obtaining at least three control samples from each origin helps to avoid random errors in subsequent processes and improves the accuracy of subsequently determined content and chemical weathering index.

[0023] In some embodiments, step S50 may further include the following steps: S51, determining a first chemical weathering index of a plurality of sandstone samples with a second particle size based on the contents of K2O, Na2O, CaO, and Al2O3 in the plurality of sandstone samples with a first particle size; S52, determining a second chemical weathering index of the plurality of sandstone samples with a second particle size based on the contents of K2O, Na2O, CaO, and Al2O3 in the plurality of sandstone samples with a first particle size. In such embodiments, by determining the first chemical weathering index and the second chemical weathering index of the plurality of sandstone samples respectively, the origin of the sandstone samples can be determined based on the first chemical weathering index and the second chemical weathering index of the plurality of sandstone samples, which helps to improve the accuracy of the determined origin of the sandstone samples.

[0024] In some embodiments, in step S70, multiple classification functions related to the origin of sandstone can be determined based on the origin of multiple control samples, the first chemical weathering index of multiple control samples, the ratio of SiO2 content to Al2O3 content of multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple control samples.

[0025] In some embodiments, step S70 may further include the following steps: S71, determining multiple characteristic values ​​related to the origin of the control samples based on the origin of the multiple control samples, the first chemical weathering index of the multiple control samples, the ratio of SiO2 content to Al2O3 content of the multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple control samples; S72, determining the significance of each characteristic value in determining the origin based on the multiple characteristic values. The contribution rate of each feature value in determining the origin is calculated as follows: S73. Based on the contribution rate of each feature value in determining the origin, multiple feature values ​​whose sum of contribution rates is greater than a preset contribution rate value are determined; S74. Based on the multiple feature values ​​determined in step S73, the first chemical weathering index of multiple control samples, the ratio of SiO2 content to Al2O3 content of multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple control samples, multiple classification functions related to the origin of sandstone are determined. Since the sum of the contribution rates of the multiple feature values ​​determined in step S73 is greater than the preset contribution rate value, the embodiments of this application, which determine multiple classification functions related to the origin of sandstone based on the multiple feature values ​​determined in step S73, can reduce the difficulty of determination and improve the efficiency of determination while ensuring accuracy.

[0026] In some embodiments, the preset contribution rate value can be 80%.

[0027] In some embodiments, in step S74, the number of classification functions determined is equal to the number of feature values ​​determined in step S73.

[0028] Specifically, the contribution rate of each characteristic value in determining the place of origin conforms to the following relationship:

[0029]

[0030] In the formula, P is the contribution rate of each eigenvalue, and λ is the contribution rate of each eigenvalue. i Let λ be the characteristic value of the contribution rate to be determined. j is the j-th feature value related to the origin of the control sample determined in step S71; n is the number of feature values ​​related to the origin of the control sample determined in step S71, and j is the summation ordinal number.

[0031] In some embodiments, in step S72, the multiple feature values ​​determined in step S71 can be sorted in order of magnitude to facilitate the determination of multiple feature values ​​whose sum of contribution rates is greater than a preset contribution rate value.

[0032] In some embodiments, step S74 may further include the following step: S741, determining that multiple classification functions related to the sandstone's origin conform to the following relationship:

[0033] Y=∑aC i +bX1+eR+d,

[0034] In the formula, Y is a symbolic value related to the sandstone's origin, a, b, e, and d are parameters, and C... i S742. Based on the multiple characteristic values ​​determined in step S73, the first chemical weathering index of multiple control samples, the ratio of SiO2 content to Al2O3 content of multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple control samples, determine a, b, e, and d. Since the sum of the contribution rates of the multiple feature values ​​determined in step S73 is greater than the preset contribution rate value, the embodiments of this application determine a, b, e, and d based on the multiple feature values ​​determined in step S73, which can not only ensure the accuracy of the determined a, b, e, and d, but also reduce the determination difficulty and improve the determination efficiency. Furthermore, the embodiments of this application determine multiple classification functions related to the sandstone's origin through the above-mentioned relationship, which is beneficial to improving the efficiency of determining the classification functions related to the sandstone's origin.

[0035] In some embodiments, step S71 may further include the following steps: S711, determining the mean of the first chemical weathering indices of the multiple control samples based on the first chemical weathering indices of the multiple control samples; S712, determining the mean of the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple control samples based on the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple control samples; S713, determining the mean of the ratio of SiO2 content to Al2O3 content in the multiple control samples based on the ratio of SiO2 content to Al2O3 content in the multiple control samples; S714, determining the first chemical weathering index of each control sample and the first chemical weathering index of each control sample based on the mean determined in step S711 and the first chemical weathering index of each control sample. S715. Based on the mean determined in step S712 and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in each control sample, determine the difference between the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in each control sample and the mean determined in step S712; S716. Based on the mean determined in step S713 and the ratio of SiO2 content to Al2O3 content in each control sample, determine the difference between the ratio of SiO2 content to Al2O3 content in each control sample and the mean determined in step S713; S717. Based on the differences determined in steps S714, S715, and S716, determine multiple characteristic values ​​related to the origin of the control samples. In such an embodiment, multiple characteristic values ​​related to the origin of the control samples are determined based on the differences between the chemical weathering index of each control sample and the mean of the chemical weathering index of the control samples, the differences between the ratio of SiO2 content to Al2O3 content of each control sample and the mean of the ratio of SiO2 content to Al2O3 content of the control samples, and the differences between the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in each control sample and the mean contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the control samples. This ensures that the determined multiple characteristic values ​​related to the origin of the control samples can comprehensively reflect the characteristics of each origin, thereby improving the efficiency and accuracy of subsequently determining the origin of multiple sandstone samples to be determined.

[0036] In some embodiments, step S717 may further include the following steps: S7171, determining a first vector composed of the differences determined in step S714; S7172, determining a plurality of second vectors composed of the differences determined in step S715; S7173, determining a third vector composed of the differences determined in step S716; S7174, determining a matrix composed of the first vector, the plurality of second vectors, and the third vector; S7175, determining an intermediate matrix related to the origin of the control sample based on the matrix determined in S7174; S7176, determining a plurality of eigenvalues ​​related to the origin of the sandstone based on the intermediate matrix determined in S7175.

[0037] Specifically, the matrix D determined in step S7174 is:

[0038]

[0039] Where, d 11 to d m1 d represents the difference determined in step S714. 12 to d m2 d 13 to d m3 d 14 to d m4 d 15 to d m5 d 16 to d m6 d 17 to d m7 This represents the difference determined in step S715; d 18 to d m8 Let m represent the difference determined in step S716, where m is the number of control samples; the intermediate matrix ∑ determined in step S7175 and the matrix D determined in step S7174 satisfy the following relationship.

[0040]

[0041] The intermediate matrix ∑ determined in step S7175 and several eigenvalues ​​related to the sandstone's origin satisfy the following relationship:

[0042] det(∑-λI)=0,

[0043] In the formula, λ is the eigenvalue related to the sandstone's origin, and I is the identity matrix with the same number of elements as the intermediate matrix ∑.

[0044] In some embodiments, step S742 may further include the following step: S7421, determining multiple intermediate vectors V that can be used to determine a, b, e, and d based on the multiple eigenvalues ​​determined in step S73 and the intermediate matrix ∑ determined in step S7175. iS7422, The intermediate vector V determined according to S7421 i The first chemical weathering index of multiple control samples, the ratio of SiO2 content to Al2O3 content of multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in multiple control samples were used to determine a, b, e, and d.

[0045] Specifically, the multiple eigenvalues ​​determined in step S73, the intermediate matrix ∑ determined in step S7175, and the intermediate vector V i It conforms to the following relationship

[0046] (∑-λ i I)V i =0,

[0047] In the formula, λ i This is the i-th eigenvalue determined in step S73.

[0048] In some embodiments, in step S7422, the first chemical weathering index of multiple control samples, the ratio of SiO2 content to Al2O3 content of multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple control samples can be correlated with the corresponding intermediate vector V. i Multiply and sum them to determine a, b, e, and d.

[0049] In some embodiments, step S80 may further include the following steps: S81, determining multiple classification function values ​​corresponding to each control sample based on the multiple classification functions determined in step S74, the first chemical weathering index of each control sample, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in each control sample, as well as the ratio of SiO2 content to Al2O3 content in each control sample; S82, determining any two control samples from the multiple control samples based on the second chemical weathering index of each control sample and the multiple classification function values ​​corresponding to each control sample. S83. Based on the distance determined in step S82, determine the relative distance between any two control samples among multiple control samples; S84. Based on the origin of multiple control samples and the relative distance between any two control samples among multiple control samples, determine the relationship between the relative distance of sandstone and the origin of sandstone; S85. Perform steps S81-S83 on multiple sandstone samples to determine the relative distance between any two sandstone samples among multiple sandstone samples; S86. Based on the relationship determined in step S84 and the relative distance determined in step S85, determine the origin of multiple sandstone samples whose origin is to be determined. In this embodiment, determining the origin of the sample whose origin is to be determined based on the relative distance between any two sandstone samples whose origin is to be determined and the relationship determined in step S84 can avoid the errors that may be caused by the aforementioned operations, and is conducive to accurately determining the origin of the sandstone sample whose origin is to be determined.

[0050] In some embodiments, step S83 may further include the following steps: S831, determining the maximum distance among the distances determined in step S82; S832, determining the maximum relative distance corresponding to the maximum distance determined in step S831; S833, determining the ratio between all distances among the distances determined in step S82 and the maximum distance; S834, determining the relative distance between any two control samples among the plurality of control samples based on the maximum relative distance determined in step S832 and the ratio determined in step S833. In such embodiments, the above steps can convert the distance between any two sandstone samples among the plurality of sandstone samples into the relative distance between any two sandstone samples among the plurality of sandstone samples, thereby reducing the difficulty in determining the relationship between the relative distance of samples from known origins and samples from known origins, and improving the efficiency of determining the origin of the sandstone sample to be determined.

[0051] In some embodiments, in step S832, the relative distance corresponding to the maximum distance determined in step S831 can be set to the standard A4 paper landscape printing size. Preferably, the relative distance corresponding to the maximum distance determined in step S831 can be set to 25 to reduce the computational workload when determining the relative distance between any two sandstone samples among a plurality of sandstone samples.

[0052] In some embodiments, the relative distance between any two sandstone samples, the distance between any two sandstone samples, the maximum distance, and the maximum relative distance satisfy the following relationship:

[0053]

[0054] In the formula, D x This represents the relative distance between any two sandstone samples from a set of multiple sandstone samples. D represents the maximum relative distance, and D represents the distance between any two sandstone samples among multiple sandstone samples. max This represents the maximum distance. In such an embodiment, the relative distance between any two sandstone samples among multiple sandstone samples can be determined efficiently and accurately based on the above relationship, which is beneficial to improving the efficiency of determining the origin of sandstone samples whose origin needs to be determined.

[0055] In some embodiments, in step S82, the second chemical weathering index of each control sample, the multiple classification function values ​​corresponding to each control sample, and the distance between any two control samples among the multiple control samples satisfy the following relationship:

[0056] D=∑(x i -y i ) 2 ,

[0057] In the formula, D is the distance between any two sandstone samples from a plurality of sandstone samples, and x i y represents the second chemical weathering index or its corresponding multiple classification function values ​​for any one of the multiple control samples. i The second chemical weathering index or its corresponding multiple classification function values ​​are used for another control sample among multiple control samples. In such an embodiment, the distance between any two sandstone samples among multiple sandstone samples can be determined efficiently and accurately according to the above relationship, which is beneficial to improving the efficiency of determining the origin of sandstone samples.

[0058] In some embodiments, step S84 further includes the following steps: S841, determining a relationship diagram between the origins of multiple control samples and the relative distances between any two control samples; S842, determining the distribution area of ​​the multiple control samples in the relationship diagram, i.e., the relationship between the relative distances of sandstone and the origins of sandstone. In such embodiments, by determining the relationship diagram, it is convenient to visually display and determine the relationship between the relative distances of sandstone and the origins of sandstone, thereby facilitating the determination of the origin of the sample whose origin is to be determined through the above relationship.

[0059] In some embodiments, in step S841, the control sample can be used as the vertical axis of the classification diagram, and the relative distance between any two samples in the control sample can be used as the horizontal axis of the classification diagram. By connecting samples belonging to the same origin, a relationship diagram can be obtained.

[0060] In some embodiments, in step S842, the origin classification distance can be determined based on the number of origins and the maximum relative distance of the control samples, and then the relationship diagram can be divided according to the determined origin classification distance to determine the distribution area of ​​the control samples in the relationship diagram. For example, if the control samples come from 3 origins and the maximum relative distance is 25, then the origin classification distance can be 10.

[0061] In some embodiments, step S85 may further include the following steps: S851, determining the positions of multiple sandstone samples in a relationship diagram based on the relative distance and relationship between any two sandstone samples; S852, determining control samples that are in the same distribution area as the sandstone sample from the to-be-determined origin in the relationship diagram based on the positions of the multiple sandstone samples in the relationship diagram and the distribution areas of multiple control samples in the relationship diagram; S853, determining the origin of the sample from the to-be-determined origin based on the origin of the control samples that are in the same distribution area as the sandstone sample from the to-be-determined origin. Since samples from the same origin are distributed in the same area in the relationship diagram, in such embodiments, by determining control samples belonging to the same origin as the sandstone sample from the to-be-determined origin based on the distribution of the sandstone sample from the to-be-determined origin in the relationship diagram and the distribution of the control samples in the relationship diagram, the origin of the sandstone sample from the to-be-determined origin can be determined based on the origin of the control samples, which is beneficial for intuitively and efficiently determining the origin of the sandstone sample from the to-be-determined origin.

[0062] In some embodiments, prior to step S70, the method further includes: S700, correcting the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple sandstone samples of the first grain size determined in step S30. In step S71, multiple characteristic values ​​related to the origin of the control samples are determined based on the origin of the multiple control samples, the first chemical weathering index of the multiple control samples, the ratio of SiO2 content to Al2O3 content of the multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers corrected in step S700. In this embodiment, the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple sandstone samples of the first grain size are first corrected. Then, based on the corrected contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers, the distance between any two sandstone samples in the multiple sandstone samples can be determined. This can reduce the complexity of the process of determining the distance between any two sandstone samples in the multiple sandstone samples and simplify the operation of determining the distance between any two sandstone samples in the multiple sandstone samples.

[0063] In some embodiments, in step S700, the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in a plurality of sandstone samples of the first grain size are multiplied by 100 to obtain the corrected contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers.

[0064] In some embodiments, step S51 may further include the following steps: S511, determining that the CaO content in each sandstone sample is greater than the Na2O content; S512, determining the first chemical weathering index of each sandstone sample based on the K2O content, Na2O content, and Al2O3 content. During the digestion process, CaO and Na2O can interfere with each other, leading to inaccurate measurements of the CaO or Na2O content. In this embodiment, by determining that the CaO content is greater than the Na2O content and determining the chemical weathering index based on the K2O content, Na2O content, and Al2O3 content, the inaccurate CaO content can be avoided from affecting the determination of the first chemical weathering index, thus ensuring the accuracy of the determined first chemical weathering index.

[0065] In some embodiments, the first chemical weathering index, K2O content, Na2O content, and Al2O3 content of multiple second-grained sandstone samples conform to the following relationship:

[0066] Z=2×Al2O3 / (Al2O3+2Na2O+K2O)×100,

[0067] In the formula, Z represents the first chemical weathering index of multiple sandstone samples with second grain size, K2O represents the K2O content, Na2O represents the Na2O content, and Al2O3 represents the Al2O3 content. In such an embodiment, the chemical weathering index of multiple sandstone samples with second grain size can be accurately determined according to the above relationship.

[0068] In some embodiments, step S51 may further include the following steps: S511', determining that the CaO content in each sandstone sample is less than or equal to the Na2O content; S512', determining the first chemical weathering index of each sandstone sample based on the K2O content, Na2O content, CaO content, and Al2O3 content. During the digestion process, CaO and Na2O can interfere with each other, leading to inaccurate measurements of the CaO or Na2O content. In the embodiments of this application, by determining that the CaO content is less than or equal to the Na2O content, and determining the chemical weathering index based on the K2O content, Na2O content, CaO content, and Al2O3 content, the determination of the first chemical weathering index can avoid affecting the accuracy of the determined first chemical weathering index.

[0069] In some embodiments, the first chemical weathering index, K2O content, Na2O content, CaO content, and Al2O3 content of multiple second-grained sandstone samples conform to the following relationship:

[0070] Z=2×Al2O3 / (Al2O3+CaO+Na2O+K2O)×100,

[0071] In the formula, Z represents the first chemical weathering index of multiple sandstone samples with second grain size, Al2O3 represents the Al2O3 content, CaO represents the CaO content, Na2O represents the Na2O content, and K2O represents the K2O content. In this embodiment, the first chemical weathering index of multiple sandstone samples with second grain size can be accurately determined according to the above relationship.

[0072] In some embodiments, in step S52, the second chemical weathering index of each sandstone sample is determined based on the K2O content, Na2O content, CaO content, Fe2O3 content, MgO content, and Al2O3 content of each sandstone sample. This is beneficial for accurately determining the second chemical weathering index of multiple sandstone samples with different grain sizes.

[0073] In some embodiments, the second chemical weathering index, K2O content, Na2O content, CaO content, Fe2O3 content, MgO content, and Al2O3 content of multiple sandstone samples with second grain size conform to the following relationship:

[0074] R=(Fe2O3+Na2O+K2O+CaO+MgO) / Al2O3,

[0075] In the formula, R represents the second chemical weathering index of multiple sandstone samples with the second grain size, Fe2O3 represents the Fe2O3 content, Na2O represents the Na2O content, K2O represents the K2O content, CaO represents the CaO content, MgO represents the MgO content, and Al2O3 represents the Al2O3 content.

[0076] In some embodiments, step S40 may further include the following steps: S41, pretreating multiple sandstone samples of the second particle size; S42, digesting the pretreated multiple sandstone samples of the second particle size; S43, determining the content of different chemical components in the digested multiple sandstone samples of the second particle size. In such embodiments, pretreating the multiple sandstone samples of the second particle size can remove calcite crystals from the multiple sandstone samples of the second particle size, avoiding the influence of calcite crystals on the measurement of the contents of K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3; at the same time, digesting the pretreated multiple sandstone samples of the second particle size allows for the measurement of the contents of K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3.

[0077] In some embodiments, in step S41, dilute hydrochloric acid can be used to pretreat multiple sandstone samples of the second grain size. In such embodiments, pretreating multiple sandstone samples of the second grain size with dilute hydrochloric acid can remove calcite crystals from the sandstone samples of the second grain size. At the same time, it can avoid affecting the measurement of the contents of K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3 in the multiple second grain sizes, which is beneficial to ensuring the accuracy of the measured contents of K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3.

[0078] In some embodiments, in step S42, multiple sandstone samples of the second particle size can be digested using a mixed acid composed of HNO3-HF-HClO4. In such embodiments, using a mixed acid composed of HNO3-HF-HClO4 to digest multiple pretreated sandstone samples of the second particle size ensures the high purity of the reagents used for digestion, avoids the introduction of impurities during digestion, and thus avoids affecting the accuracy of the measured contents of K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3.

[0079] In some embodiments, step S30 may further include the following steps: S31, compressing multiple sandstone samples of the first grain size into multiple compressed samples; S32, repeatedly measuring the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple compressed samples, and taking the average value of the multiple repeated measurements as the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple sandstone samples of the first grain size. In this embodiment, compressing the sandstone sample of the first grain size into a pellet sample can reduce the voids in the sample, ensure measurement accuracy, and facilitate accurate measurement of the content. This improves the accuracy of the measured contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers. Furthermore, performing multiple repeated measurements on the pellet sample and taking the average of the multiple repeated measurements as the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple sandstone samples of the first grain size can avoid random errors during measurement and also improve the accuracy of the measured contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers.

[0080] In some embodiments, in step S31, a tablet press can be used to compress multiple sandstone samples of the first particle size into multiple tablet samples. Specifically, the pressure of the tablet press can be set to a maximum of 20 tons, with constant pressure compression for 1 minute.

[0081] In the embodiments of this application, by pressing sandstone samples of the first particle size into pellet samples under constant pressure, it is beneficial to ensure that the internal structure of the pressed pellet samples is uniform, and it is beneficial to accurately measure the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers.

[0082] In some embodiments, in step S32, X-rays can be used to measure the content of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixtures, and illite / montmorillonite mixtures in the compressed sample. Specifically, the X-ray tube voltage can be set to a maximum value of 50 kV, the current can be set to a maximum value of 100 mA, and the detection time can be set to 30 seconds.

[0083] In some embodiments, in step S32, each compressed sample may be measured 3 to 10 times, and the average value of the 3 to 10 measurements may be taken as the content of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the sandstone sample of the first grain size. For example, each compressed sample may be measured 5 times.

[0084] In some embodiments, prior to step S31, the process may further include: S300, pre-treating multiple sandstone samples of a first particle size with H2O2 or dilute acetic acid, and extracting clay particles with a particle size less than 2 μm using sedimentation or centrifugation. In step S31, the clay particles extracted in step S300 are compressed into tablet samples. In this embodiment, multiple sandstone samples of the first particle size are treated with H2O2 or dilute acetic acid, which transforms the sandstone samples of the first particle size into clay particles, facilitating the subsequent extraction of clay particles with a particle size of less than 2 μm. Simultaneously, treating multiple sandstone samples of the first particle size with H2O2 or dilute acetic acid avoids the added reagents affecting the illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the sandstone samples of the first particle size. This facilitates accurate measurement of the contents of these elements in the sandstone samples of the first particle size. Furthermore, the extraction of clay particles with a particle size of less than 2 μm makes it easier to compress the clay particles into pellet samples in step S31.

[0085] The process of determining the sandstone deposit using the method provided in the embodiments of this application is described below. A total of 21 samples from known deposits were collected, all of which were Cretaceous sandstone samples. These 21 samples came from the Songliao Basin, Erlian Basin, Ordos Basin, and Junggar Basin, respectively. Specifically, there were 5 samples from the Songliao Basin, 4 samples from the Erlian Basin, 8 samples from the Ordos Basin, and 4 samples from the Junggar Basin.

[0086] (1) First, the above 21 samples were made into 21 70-mesh samples and 21 200-mesh samples respectively according to 70-mesh and 200-mesh; then, the 21 70-mesh samples were treated with dilute acetic acid and clay particles with a particle size of less than 2μm were extracted after treatment; then, the clay particles were pressed into 21 tablet samples by pressing them under a pressure of 20 tons for 1 minute using a tablet press.

[0087] (2) Then, the X-ray tube voltage was set to the maximum value of 50kV, the current was set to the maximum value of 100mA, and the detection time was set to 30 seconds. The contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer in 21 compressed samples were measured using X-rays emitted by the X-ray tube. Each compressed sample was measured 5 times, and the average value of the 5 measurements was taken as the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer in each 70-mesh sample.

[0088] (3) The 21 samples of 200 mesh were pretreated with dilute hydrochloric acid. After the pretreatment was completed, the 21 samples of 200 mesh were digested with HNO3-HF-HClO4. The contents of SiO2, K2O, Na2O, CaO and Al2O3 in the 21 samples of 200 mesh were measured. Then, based on the measured contents of SiO2, K2O, Na2O, CaO and Al2O3 in the 21 samples of 200 mesh, the first chemical weathering index X1, the second chemical weathering index X2 and the ratio of SiO2 content to Al2O3 content of each 200 mesh sample were determined. Referring to Table 1 below, the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in 21 70-mesh samples, as well as the first chemical weathering index X1 of 21 200-mesh samples and the ratio of SiO2 content to Al2O3 content of 21 200-mesh samples are shown in Table 1 below.

[0089] Table 1. Contents of the above-mentioned substances, first chemical weathering index, and ratio of SiO2 content to Al2O3 content in 21 samples.

[0090]

[0091]

[0092] (4) Multiply the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the 21 70-mesh samples by 100 for correction; then, determine the intermediate matrix ∑ based on the first chemical weathering index of the 21 200-mesh samples and the corrected contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the 21 70-mesh samples, as well as the ratio of SiO2 content to Al2O3 content in the 21 200-mesh samples.

[0093] Referring to Table 2 below, the elements in the determined intermediate matrix ∑ are shown in Table 2.

[0094] The elements in the intermediate matrix ∑ determined in Table 2

[0095]

[0096] (5) Based on the above intermediate matrix, eight eigenvalues ​​are calculated; then the contribution rate of these eight eigenvalues ​​and the sum of their contribution rates (also known as the cumulative contribution rate) are calculated.

[0097] Referring to Table 3 below, the calculated 8 eigenvalues, the contribution rate of the 8 eigenvalues, and the cumulative contribution rate of the 8 eigenvalues ​​are shown in Table 3.

[0098] Table 3 shows the determined eigenvalues, their contribution rates, and cumulative contribution rates.

[0099]

[0100]

[0101] As shown in Table 3, the first seven eigenvalues ​​are all greater than 1. Among them, the first eigenvalue λ1 reaches 1420.314, with a contribution rate of 71.691%; the second eigenvalue λ2 is 425.752, with a contribution rate of 93.181%; and the third eigenvalue λ3 is 77.204, with a contribution rate of 97.078%. The cumulative contribution rate of the first two eigenvalues ​​has reached 93.181%, which is greater than the preset contribution rate value of 80%. Therefore, the first and second classification functions related to the sandstone's origin are determined based on the first two eigenvalues.

[0102] Refer to Table 4 below. The coefficients of each item in the first classification function and the second classification function determined based on the first two feature values ​​are shown in Table 4.

[0103] Table 4 shows the coefficients of each item in the classification function.

[0104] illite -0.120 0.313 chlorite -0.086 0.285 Montmorillonite 0.096 -0.048 Kaolinite -0.003 -0.010 Chlorite / montmorillonite mixed layer 0.524 -0.437 illite / montmorillonite mixed layer -0.430 -0.691 <![CDATA[X1]]> -0.003 0.003 <![CDATA[SiO2 / Al2O3]]> 0.032 -0.022

[0105] Based on the coefficients in Table 4 above, the first classification function and the second classification function are determined as follows:

[0106] Y1=-0.12×Ill-0.086×Chl+0.096×Mnt-0.003×Kln+0.524×CM-

[0107] 0.43×IM-0.003×X1+0.032×SiO2 / Al2O3,

[0108] Y2=0.313×Ill+0.285×Chl-0.048×Mnt-0.01×Kln-0.437×CM-

[0109] 0.691×IM+0.003×X1-0.022×SiO2 / Al2O3,

[0110] Wherein, Y1 and Y2 are the first and second classification function values, Ill is the illite content, Chl is the chlorite content, Mnt is the montmorillonite content, Kln is the kaolinite content, CM is the chlorite / montmorillonite mixed layer content, IM is the illite / montmorillonite mixed layer content, X1 is the first chemical weathering index, and SiO2 / Al2O3 is the ratio of SiO2 content to Al2O3 content.

[0111] (6) Substitute the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the 21 70-mesh samples, the first chemical weathering index of the 21 200-mesh samples, and the ratio of SiO2 content to Al2O3 content in the 21 200-mesh samples into the two classification functions mentioned above to obtain the first classification function value Y1 and the second classification function value Y2 of the 21 samples; then, based on the first classification function value Y1, the second classification function value Y2, and the second chemical weathering index X2 of the 21 200-mesh samples, calculate the distance between any two samples in the 21 samples.

[0112] Refer to Tables 5, 6, and 7 below. Table 5 shows the first classification function value Y1, the second classification function value Y2, and the second chemical weathering index X2 of the 21 samples at 200 mesh. Tables 6 and 7 show the distance between any two samples among the 21 samples. Table 5: First classification function value Y1, second classification function value Y2, and second chemical weathering index X2 of the 21 samples at 200 mesh.

[0113]

[0114]

[0115] Table 6. Distance between any two samples out of the 21 samples

[0116]

[0117]

[0118] Table 7. Distance between any two samples out of the 21 samples

[0119]

[0120] In Tables 6 and 7, the first column and first row of 1 represent samples from the Songliao Basin, the first column and first row of 2 represent samples from the Erlian Basin, the first column and first row of 3 represent samples from the Ordos Basin, and the first column and first row of 4 represent samples from the Junggar Basin.

[0121] (7) Sort the 441 distances D between the 21 samples by size, and select the largest distance D. max 15.425 is converted to a maximum relative distance of 25. The distances between any two samples are converted to the corresponding relative distances according to the ratio of this distance to the maximum distance.

[0122] (8) Based on the relative distance between any two samples out of the 21 samples and the origin of the 21 samples, determine the classification map. See [reference needed]. Figure 2 , Figure 2 It is based on Figure 1 The diagram shows the relationship between the origin of the control sample and the relative distance between the control samples, as determined by the method. Figure 2 The 21 samples came from 4 origins, and the origin classification distance was set to 5. Figure 2 As can be seen, sandstone samples were categorized according to their origin. Cutting the dendrogram at a relative distance of 5, the sandstone samples were divided into 4 categories. It can be seen that the 8 sandstone samples from the Ordos Basin and the 4 sandstone samples from the Erlian Basin were well divided into two categories. Except for 2 sandstone samples from the Junggar Basin that were misclassified as belonging to the Erlian Basin, and 1 sample from the Songliao Basin that was classified into a separate category, the rest were correctly classified. Therefore, it is evident that the method of this invention for classifying sandstone samples according to their origin achieves accurate classification of the vast majority of sandstone samples according to their origin.

[0123] (9) Obtain multiple (e.g., 17) sandstone samples, and perform steps (1) to (7) on the multiple sandstone samples. Based on the relative distance between any two sandstone samples, determine the position of each sandstone sample on the classification map, and then determine the origin of each sandstone sample.

[0124] Regarding the embodiments of this application, it should also be noted that, without conflict, the embodiments of this application and the features in the embodiments can be combined with each other to obtain new embodiments.

[0125] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. The scope of protection of this application shall be determined by the scope of the claims.

Claims

1. A method for determining the origin of sandstone, characterized in that, The method includes the following steps: S10. Obtain multiple sandstone samples from locations to be determined; S20. The multiple sandstone samples are made into multiple sandstone samples with a first particle size and multiple sandstone samples with a second particle size, wherein the first particle size is larger than the second particle size. S30. Determine the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the plurality of sandstone samples of the first grain size; S40. Determine the contents of SiO2, K2O, Na2O, CaO and Al2O3 in the plurality of second-size sandstone samples; S50. Based on the SiO2, K2O, Na2O, CaO and Al2O3 contents in the plurality of second-grain size sandstone samples determined in step S40, determine the chemical weathering index and the ratio of SiO2 content to Al2O3 content of the plurality of second-grain size sandstone samples. S60. Obtain multiple control samples with known origins, and perform steps S20-S50 on the multiple control samples; S70. Based on the origin of the multiple control samples, the chemical weathering index of the multiple control samples, the ratio of SiO2 content to Al2O3 content of the multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the multiple control samples, determine multiple classification functions related to the origin of sandstone. S80. Based on the multiple classification functions determined in step S70, the chemical weathering index of the multiple control samples, the ratio of SiO2 content to Al2O3 content of the multiple control samples, the ratio of SiO2 content to Al2O3 content in the multiple sandstone samples, the chemical weathering index of the multiple sandstone samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple control samples and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple sandstone samples, determine the origin of the multiple sandstone samples whose origin is to be determined. The S50 step also includes the following steps: S51. Determine the first chemical weathering index of the multiple sandstone samples with second particle size based on the contents of K2O, Na2O, CaO and Al2O3 in the multiple sandstone samples with second particle size. S52. Determine the second chemical weathering index of the multiple sandstone samples with second particle size based on the contents of K2O, Na2O, CaO, Fe2O3, MgO and Al2O3 in the multiple sandstone samples with second particle size. Step S70 also includes the following steps: S71. Based on the origin of the multiple reference samples, the first chemical weathering index of the multiple reference samples, the ratio of SiO2 content to Al2O3 content of the multiple reference samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the multiple reference samples, determine multiple characteristic values ​​related to the origin of the reference samples. S72. Based on the plurality of feature values, determine the contribution rate of each feature value in determining the place of origin; S73. Based on the contribution rate of each of the feature values ​​in determining the place of origin, determine a plurality of feature values ​​whose sum of contribution rates is greater than a preset contribution rate value; S74. Based on the multiple characteristic values ​​determined in step S73, the first chemical weathering index of the multiple control samples, the ratio of SiO2 content to Al2O3 content of the multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple control samples, determine the multiple classification functions related to the origin of the sandstone. The S80 step also includes the following steps: S81. Based on the multiple classification functions determined in step S74, the first chemical weathering index of each control sample, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in each control sample, as well as the ratio of SiO2 content to Al2O3 content in each control sample, determine the multiple classification function values ​​corresponding to each control sample. S82. Determine the distance between any two of the multiple control samples based on the second chemical weathering index of each control sample and the multiple classification function values ​​corresponding to each control sample; S83. Based on the distance determined in step S82, determine the relative distance between any two of the plurality of control samples; S84. Based on the origin of the plurality of control samples and the relative distance between any two of the plurality of control samples, determine the relationship between the relative distance of sandstone and the origin of sandstone. S85. Perform steps S81-S83 on the plurality of sandstone samples to determine the relative distance between any two of the sandstone samples. S86. Based on the relationship determined in step S84 and the relative distance determined in step S85, determine the origin of the multiple sandstone samples whose origins are to be determined.

2. The method according to claim 1, characterized in that, Step S74 also includes the following steps: S741. Determine that multiple classification functions related to the sandstone's origin conform to the following relationship: ， In the formula, Let a, b, e, and d be the classification function values ​​related to the sandstone's origin, and a, b, e, and d be the parameters. The content of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the control sample or the sandstone sample. The first chemical weathering index of the control sample or the sandstone sample. The ratio of SiO2 content to Al2O3 content in the control sample or the sandstone sample; S742. Based on the multiple characteristic values ​​determined in step S73, the first chemical weathering index of the multiple control samples, the ratio of SiO2 content to Al2O3 content of the multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the multiple control samples, determine a, b, e, and d.

3. The method according to claim 1, characterized in that, Step S71 also includes the following steps: S711. Determine the mean value of the first chemical weathering index of the plurality of control samples based on the first chemical weathering index of the plurality of control samples; S712. Based on the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the multiple reference samples, determine the average contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the multiple reference samples. S713. Determine the average value of the ratio of SiO2 content to Al2O3 content of the multiple control samples based on the ratio of SiO2 content to Al2O3 content of the multiple control samples. S714. Based on the mean value determined in step S711 and the first chemical weathering index of each control sample, determine the difference between the first chemical weathering index of each control sample and the mean value determined in step S711. S715. Based on the mean value determined in step S712 and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in each of the control samples, determine the difference between the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in each of the control samples and the mean value determined in step S712. S716. Based on the mean value determined in step S713 and the ratio of SiO2 content to Al2O3 content of each control sample, determine the difference between the ratio of SiO2 content to Al2O3 content of each control sample and the mean value determined in step S713. S717. Based on the difference determined in step S714, step S715, and step S716, determine the plurality of characteristic values ​​related to the origin of the control sample.

4. The method according to claim 1, characterized in that, Step S83 also includes the following steps: S831. Determine the maximum distance among the distances determined in step S82; S832. Determine the maximum relative distance corresponding to the maximum distance determined in step S831; S833. Determine the ratio between all distances in the distance determined in step S82 and the maximum distance; S834. Based on the maximum relative distance determined in step S832 and the ratio determined in step S833, determine the relative distance between any two of the plurality of control samples.

5. The method according to claim 1, characterized in that, In step S82, the second chemical weathering index of each control sample, the multiple classification function values ​​corresponding to each control sample, and the distance between any two control samples satisfy the following relationship: ， In the formula, The distance between any two of the sandstone samples from the plurality of sandstone samples. The second chemical weathering index or its corresponding multiple classification function values ​​are any one of the plurality of control samples. The second chemical weathering index or its corresponding multiple classification function values ​​are for another of the plurality of control samples.

6. The method according to claim 1, characterized in that, Step S84 also includes the following steps: S841. Determine the relationship between the place of origin of the plurality of control samples and the relative distance between any two of the plurality of control samples; S842. Determine the distribution area of ​​the multiple control samples in the relationship diagram, that is, the relationship between the relative distance of sandstone and the origin of sandstone.

7. The method according to claim 6, characterized in that, Step S85 also includes the following steps: S851. Determine the position of the multiple sandstone samples in the relationship diagram based on the relative distance between any two sandstone samples and the relationship diagram. S852. Based on the positions of the multiple sandstone samples in the relationship diagram and the distribution areas of the multiple control samples in the relationship diagram, determine the control samples that are in the same distribution area as the sandstone samples from the undetermined origin in the relationship diagram; S853. Determine the origin of the sample whose origin is to be determined based on the origin of the control sample which is located in the same distribution area as the sandstone sample whose origin is to be determined.

8. The method according to claim 2, characterized in that, Before step S70, the following are also included: S700, Correct the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple sandstone samples of the first grain size determined in step S30. In step S71, based on the origin of the multiple control samples, the first chemical weathering index of the multiple control samples, the ratio of SiO2 content to Al2O3 content of the multiple control samples, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer as corrected in step S700, multiple characteristic values ​​related to the origin of the control samples are determined.

9. The method according to claim 1, characterized in that, Step S51 also includes the following steps: S511. Determine that the CaO content in each of the sandstone samples is greater than the Na2O content; S512. Determine the first chemical weathering index of each sandstone sample based on the K2O content, Na2O content, and Al2O3 content in each sandstone sample.

10. The method according to claim 1, characterized in that, Step S51 also includes the following steps: S511' Determine that the CaO content in each of the sandstone samples is less than or equal to the Na2O content; S512' Determine the first chemical weathering index of each sandstone sample based on the K2O content, Na2O content, CaO content and Al2O3 content in each sandstone sample.

Images