Method of determining the origin of sandstone

Abstract

The embodiments of this application relate to the field of testing or analyzing materials by measuring their chemical or physical properties, specifically relating to a method for determining the origin of sandstone. This method includes: acquiring multiple sandstone samples with the origin to be determined and multiple control samples with known origins; determining the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, illite / montmorillonite mixed layers, K₂O, Na₂O, CaO, Fe₂O₃, MgO, Al₂O₃, and a chemical weathering index in the multiple sandstone samples and the multiple control samples, respectively; and determining the origin of each sandstone sample with the origin to be determined based on the aforementioned contents of the multiple control samples, the chemical weathering index of the multiple control samples, the aforementioned contents of the multiple sandstone samples, and the chemical weathering index of the multiple sandstone samples. The method provided by the embodiments of this application can effectively and accurately determine the origin of sandstone samples with the origin 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 locations to be determined; 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 K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3 in the multiple sandstone samples of the second grain size; S50, determining the contents of K2O, Na2O, CaO, Fe2O3, and Al2O3 in the multiple sandstone samples of the second grain size determined according to step S40. S60: Determine the chemical weathering index of multiple second-grained sandstone samples by measuring the contents of gO and Al2O3; S70: Obtain multiple control samples from known origins and perform steps S20-S50 on the multiple control samples; S70: Determine the origin of each sandstone sample from which an origin needs to be determined based on the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple first-grained sandstone samples determined in step S30, the chemical weathering index determined in step S50, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple first-grained control samples determined in step S60, and the chemical weathering index.

[0008] The method provided in this application determines the origin of a sandstone sample by determining the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the sandstone sample; the contents of K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3 in the sandstone sample; the chemical weathering index of the sandstone sample; and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in a control sample, as well as the contents of K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3 in the control sample and the chemical weathering index of the control sample. Based on the above contents and chemical weathering index, the origin of the sandstone sample to be determined can be determined. This method not only effectively determines the origin of the sandstone sample to be determined but also improves the accuracy of the determined origin of the sandstone sample. This improves accuracy, 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 on the sandstone and control samples can be minimized, reducing intermediate steps and thus lowering the probability of contamination. This facilitates accurate measurement of the aforementioned contents and chemical weathering index of the samples. Additionally, preparing the sandstone 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 K2O, Na2O, CaO, Fe2O3, MgO, 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 of a method provided in an embodiment of this application.

[0011] Figure 2 It is based on Figure 1 The diagram shows the relationship between the relative distances between the control sample and the control sample determined by the method.

[0012] Explanation of reference numerals in the attached figures:

[0013] 41. Category I samples; 42. Category II samples; 43. Category III samples; 44. Category IV samples; 45. Category V samples.

[0014] 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

[0015] 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.

[0016] It should also be noted that, in order to avoid obscuring this application with unnecessary details, only the device 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.

[0017] In related technologies, the chemical and mineral composition of sandstone is used to determine its origin. However, in the process of determining the origin of sandstone, there are problems such as ineffective determination and low accuracy.

[0018] To address the aforementioned issues, embodiments of this application provide a method for determining the origin of sandstone.

[0019] See Figure 1 , Figure 1This is a flowchart of a method provided in an embodiment of this application. The method includes the following steps: S10, obtaining multiple sandstone samples of unknown origin; 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 K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3 in the multiple sandstone samples of the second grain size; S50, determining the contents of K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3 in the multiple sandstone samples of the second grain size as determined in step S40. S60: Determine the chemical weathering index of multiple second-grained sandstone samples based on the contents of O, Fe2O3, MgO, and Al2O3; S70: Obtain multiple control samples from known origins and perform steps S20-S50 on the multiple control samples; S70: Based on the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple first-grained sandstone samples determined in step S30, and the chemical weathering index determined in step S50, as well as the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in multiple first-grained control samples determined in step S60, determine the origin of each sandstone sample from which the origin to be determined is located.

[0020] The method provided in this application determines the origin of a sandstone sample by determining the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in a sandstone sample; the contents of K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3 in the sandstone sample; the chemical weathering index of the sandstone sample; the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in samples from known origins; the contents of K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3 in samples from known origins; and the chemical weathering index of samples from known origins. Based on the above contents and chemical weathering index, the origin of the sandstone sample to be determined can be determined. This method not only effectively determines the origin of the sandstone sample to be determined but also improves the accuracy of the determined origin determination. This improves accuracy, thus providing reliable and accurate technical support for geological research and resource exploration. Furthermore, by preparing sandstone samples and samples from known origins into first- and second-grained samples, the processing work on the sandstone samples and samples from known origins can be minimized, reducing intermediate steps and thus lowering the probability of contamination. This facilitates accurate measurement of the aforementioned contents and chemical weathering index of the samples. Moreover, preparing the sandstone samples and samples from known origins 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 K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3 in the samples.

[0021] 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.

[0022] In some embodiments, the second particle size can be 200 mesh to facilitate the measurement of the contents of K2O, Na2O, CaO, Fe2O3, MgO, and Al2O3 in the sample with the second particle size.

[0023] 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.

[0024] 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.

[0025] In some embodiments, step S70 may further include the following steps: S71, determining the distance between any two sandstone samples among the plurality of sandstone samples based on 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 determined in step S30 and the chemical weathering index determined in step S50; S72, determining the relative distance between any two sandstone samples among the plurality of sandstone samples based on the distance determined in step S71; S73, determining the relationship between the relative distance of the control sample and the control sample by performing steps S71-S72 on the control sample; S74, determining the origin of the sample whose origin is to be determined based on the relative distance between any two sandstone samples of the sandstone sample whose origin is to be determined and the relationship determined in step S73. In such an embodiment, the origin of the sample to be determined is determined based on the relative distance between any two sandstone samples of the sandstone sample to be determined and the relationship determined in step S73. This can avoid the errors that may be caused by the aforementioned operations and is conducive to accurately determining the origin of the sandstone sample to be determined.

[0026] In some embodiments, step S72 may further include the following steps: S721, determining the maximum distance among the distances determined in step S71; S722, determining the relative distance corresponding to the maximum distance determined in step S721; S723, determining the ratio between all distances among the distances determined in step S71 and the maximum distance; S724, determining the relative distance between any two sandstone samples among the plurality of sandstone samples based on the relative distance determined in step S722 and the ratio determined in step S723. 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 deposits and samples from known deposits, and improving the efficiency of determining the deposit of the sandstone sample to be determined.

[0027] In some embodiments, in step S722, the relative distance corresponding to the maximum distance determined in step S721 can be set to the standard A4 paper landscape printing size. Preferably, the relative distance corresponding to the maximum distance determined in step S721 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.

[0028] 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:

[0029]

[0030] 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.

[0031] In some embodiments, in step S71, 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 determined in step S30, the chemical weathering index determined in step S50, and the distance between any two sandstone samples among the plurality of sandstone samples satisfy the following relationship:

[0032] D=∑(x i -y i ) 2 ,

[0033] In the formula, D is the distance between any two sandstone samples from a plurality of sandstone samples, and x i The content or chemical weathering index of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in any one of multiple sandstone samples of the first grain size, y i This refers to the content or chemical weathering index of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, illite / montmorillonite mixed layers in another sandstone sample from a plurality of sandstone samples of the first grain size. In such an embodiment, the distance between any two sandstone samples from a plurality of 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 whose origin needs to be determined.

[0034] In some embodiments, step S73 may further include the following steps: S731, determining a relationship diagram between the relative distances of the control samples; S732, determining the distribution area of ​​the control samples in the relationship diagram. In such embodiments, by determining the relationship diagram, it is convenient to visually display and determine the distribution pattern of the control samples, and thus convenient to determine the origin of the sample whose origin is to be determined based on the distribution pattern of the control samples.

[0035] In some embodiments, in step S731, 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.

[0036] In some embodiments, in step S732, 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.

[0037] In some embodiments, step S74 may further include the following steps: S741, determining the position of the sandstone sample whose origin is to be determined in the relationship diagram based on the relative distance and relationship diagram between any two sandstone samples of the sandstone sample whose origin is to be determined; S742, determining the control sample that is in the same distribution area as the sandstone sample whose origin is to be determined in the relationship diagram based on the position of the sandstone sample whose origin is to be determined in the relationship diagram and the distribution area of ​​the control sample in the relationship diagram; S743, determining the origin of the sample whose origin is to be determined based on the origin of the control sample that is in the same distribution area as the sandstone sample whose origin is to be determined. Since samples from the same origin are distributed in the same area in the relationship diagram, in such embodiments, the control sample belonging to the same origin as the sandstone sample whose origin is to be determined can be determined based on the distribution of the sandstone sample whose origin is to be determined in the relationship diagram and the distribution of the control sample in the relationship diagram. This allows the origin of the sandstone sample whose origin is to be determined to be determined to be determined based on the origin of the control sample, which is beneficial for determining the origin of the sandstone sample whose origin is to be determined intuitively and efficiently.

[0038] 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 plurality of sandstone samples of the first grain size determined in step S30. In step S71, the distance between any two sandstone samples among the plurality of sandstone samples is determined based on the corrected contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers from step S700 and the chemical weathering index determined in step S50. 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] In some embodiments, in step S42, a mixed acid consisting of HNO3-HF-HClO4 can be used to digest multiple pretreated sandstone samples of the second particle size. In such embodiments, using multiple pretreated sandstone samples of the second particle size to digest other 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.

[0043] In some embodiments, step S50 may further include the following steps: S51, determining that the CaO content is greater than the Na2O content; S52, determining the chemical weathering index of multiple sandstone samples with second particle size based on the K2O content, Na2O content, Fe2O3 content, MgO content, and Al2O3 content. During the digestion process, CaO and Na2O can interfere with each other, leading to inaccurate measurements of either 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, Fe2O3 content, MgO content, and Al2O3 content, the inaccurate measurement of the CaO content can be avoided from affecting the determined chemical weathering index, thus ensuring the accuracy of the determined chemical weathering index.

[0044] In some embodiments, the chemical weathering index, K2O content, Na2O content, Fe2O3 content, MgO content, and Al2O3 content of multiple second-grained sandstone samples conform to the following relationship:

[0045] Z=2×(K2O+2Na2O+Fe2O3+MgO) / Al2O3,

[0046] In the formula, Z represents the chemical weathering index of multiple second-grained sandstone samples, K2O represents the K2O content, Na2O represents the Na2O content, Fe2O3 represents the Fe2O3 content, MgO represents the MgO content, and Al2O3 represents the Al2O3 content. In this embodiment, the chemical weathering index of multiple second-grained sandstone samples can be accurately determined according to the above relationship.

[0047] In some embodiments, step S50 may further include the following steps: S51', determining that the CaO content is less than or equal to the Na2O content; S52', determining the chemical weathering index of multiple sandstone samples with second particle size based on the K2O content, Na2O content, CaO content, Fe2O3 content, MgO 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, Fe2O3 content, MgO content, and Al2O3 content, the accuracy of the determined chemical weathering index can be ensured by avoiding any impact on the determined chemical weathering index.

[0048] In some embodiments, the chemical weathering index, K2O content, Na2O content, CaO content, Fe2O3 content, MgO content, and Al2O3 content of multiple second-grained sandstone samples conform to the following relationship:

[0049] Z=2×(K2O+Na2O+CaO+Fe2O3+MgO) / Al2O3,

[0050] In the formula, Z represents the chemical weathering index of multiple second-grained sandstone samples, K2O represents the K2O content, Na2O represents the Na2O content, CaO represents the CaO content, Fe2O3 represents the Fe2O3 content, MgO represents the MgO content, and Al2O3 represents the Al2O3 content. In this embodiment, the chemical weathering index of multiple second-grained sandstone samples can be accurately determined according to the above relationship.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] The process of determining the sandstone deposit using the method provided in the embodiments of this application is described below. A total of 17 samples from known deposits were collected, all of which were Cretaceous sandstone samples. These 17 samples came from the Songliao Basin, the Erlian Basin, and the Ordos Basin, respectively. Specifically, there were 5 samples from the Songliao Basin, 4 samples from the Erlian Basin, and 8 samples from the Ordos Basin.

[0058] (1) First, the above 17 samples were made into 17 70-mesh samples and 17 200-mesh samples respectively according to 70-mesh and 200-mesh; then, the 17 70-mesh samples were treated with dilute acetic acid and clay particles with a particle size of less than 2 μm were extracted after treatment; then, the clay particles were pressed into 17 tablet samples by pressing them under a pressure of 20 tons for 1 minute using a tablet press.

[0059] (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 17 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.

[0060] (3) Seventeen 200-mesh samples were pretreated with dilute hydrochloric acid. After pretreatment, the 17 200-mesh samples were digested with HNO3-HF-HClO4. The contents of K2O, Na2O, CaO, Fe2O3, MgO and Al2O3 in the 17 200-mesh samples after digestion were measured. Then, based on the measured contents of K2O, Na2O, CaO, Fe2O3, MgO and Al2O3 in the 17 200-mesh samples, the chemical weathering index of each 200-mesh sample was determined.

[0061] Referring to Table 1 below, the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in 17 70-mesh samples, as well as the chemical weathering index of 17 200-mesh samples, are shown in Table 1 below.

[0062] Table 1. Content and chemical weathering index of the above in 17 samples

[0063]

[0064]

[0065] (4) Multiply the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the 17 70-mesh samples by 100 for correction; then, calculate the distance between any two samples in the 17 samples based on the corrected contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer and the chemical weathering index of the 17 200-mesh samples.

[0066] Referring to Tables 2 and 3 below, the distance between any two samples among the 17 samples is shown in Tables 2 and 3 below.

[0067] Table 2. Distances between any two samples out of the 17 samples

[0068]

[0069]

[0070] Table 3. Distances between any two samples out of the 17 samples

[0071]

[0072]

[0073] (5) Sort the 289 distances D between the 17 samples by size, and select the largest distance D. max9994.04 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.

[0074] (6) Based on the relative distances between the 17 samples and the 17 samples themselves, determine the classification map. See [reference needed]. Figure 2 , Figure 2 It is based on Figure 1 The diagram shown illustrates the relationship between the relative distances between the control sample and the control sample determined by the method. Figure 2 The 17 samples came from 3 origins, and the origin classification distance was set to 10. Figure 2 As can be seen, when the classification map is cut off at a relative distance of 10, the sandstone samples are divided into three categories: Category 1 sample 41 contains 4 samples from the Erlian Basin; Category 2 sample 42 contains 5 samples from the Songliao Basin; and Category 3 sample 43 contains 8 samples from the Ordos Basin. As the relative distance increases, Category 2 sample 42 and Category 3 sample 43 merge into Category 4 sample 44 at a relative distance of 15, and finally merge with Category 1 sample 41 at a relative distance of 25 to form Category 5 sample 45.

[0075] (7) Obtain multiple (e.g., 17) sandstone samples, and perform steps (1) to (5) 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.

[0076] 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.

[0077] The above description is merely a specific embodiment 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 K2O, Na2O, CaO, Fe2O3, MgO and Al2O3 in the plurality of sandstone samples with second grain size; S50. Based on the contents of K2O, Na2O, CaO, Fe2O3, MgO and Al2O3 in the plurality of second-grain size sandstone samples determined in step S40, determine the chemical weathering index of the plurality of second-grain size sandstone samples. S60. Obtain multiple control samples from known origins, and perform steps S20-S50 on the multiple control samples; S70. Based on 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 determined in step S30, and the chemical weathering index determined in step S50, as well as the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the plurality of control samples of the first grain size determined in step S60, determine the origin of each sandstone sample whose origin is to be determined. Step S70 also includes the following steps: S71. Based on the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the plurality of sandstone samples of the first grain size determined in step S30 and the chemical weathering index determined in step S50, determine the distance between any two of the plurality of sandstone samples. S72. Based on the distance determined in step S71, determine the relative distance between any two sandstone samples among the plurality of sandstone samples; S73. Determine that steps S71-S72 are performed on the control sample to determine the relationship between the relative distance of the control sample and the control sample; S74. Determine the origin of the sandstone sample to be determined based on the relative distance between any two sandstone samples and the relationship determined in step S73. 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, the distance between any two sandstone samples among the plurality of sandstone samples is determined based on the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer as corrected in step S700 and the chemical weathering index determined in step S50. The S50 step also includes the following steps: S51. Determine that the CaO content is greater than the Na2O content; S52. Determine the chemical weathering index of the plurality of second-grain size sandstone samples based on the K2O content, Na2O content, Fe2O3 content, MgO content, and Al2O3 content. The S50 step also includes the following steps: S51' Determine that the CaO content is less than or equal to the Na2O content; S52'. Based on the K2O content, Na2O content, CaO content, Fe2O3 content, MgO content, and Al2O3 content, determine the chemical weathering index of the plurality of second-grain size sandstone samples.

2. The method according to claim 1, characterized in that, Step S72 also includes the following steps: S721. Determine the maximum distance among the distances determined in step S71; S722. Determine the maximum relative distance corresponding to the maximum distance determined in step S721; S723. Determine the ratio between all distances in the distance determined in step S71 and the maximum distance; S724. Based on the maximum relative distance determined in step S722 and the ratio determined in step S723, determine the relative distance between any two sandstone samples among the plurality of sandstone samples.

3. The method according to claim 1, characterized in that, In step S71, 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 determined in step S30, the chemical weathering index determined in step S50, and the distance between any two of the plurality of sandstone samples satisfy the following relationship: ， In the formula, The distance between any two of the sandstone samples from the plurality of sandstone samples. The content of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, illite / montmorillonite mixed layers, or the chemical weathering index of any one of the plurality of sandstone samples of the first grain size. The illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer content, or the chemical weathering index of another sandstone sample among the plurality of sandstone samples of the first grain size.

4. The method according to claim 1, characterized in that, Step S73 also includes the following steps: S731. Determine the relationship diagram between the relative distances of the control sample and the control sample; S732. Determine the distribution area of ​​the control sample in the relationship diagram.

5. The method according to claim 4, characterized in that, Step S74 also includes the following steps: S741. Based on the relative distance between any two sandstone samples of the sandstone samples whose origin is to be determined and the relationship diagram, determine the position of the sandstone sample of the sandstone samples whose origin is to be determined in the relationship diagram; S742. Based on the position of the sandstone sample from the undetermined origin in the relationship diagram and the distribution area of ​​the control sample in the relationship diagram, determine the control sample that is in the same distribution area as the sandstone sample from the undetermined origin in the relationship diagram. S743. 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.

6. The method according to claim 1, characterized in that, Step S40 also includes the following steps: S41. Pre-process the plurality of sandstone samples with the second grain size; S42. The pre-treated sandstone samples of the second particle size; S43. Determine the content of different chemical components in the plurality of second-grain size sandstone samples after digestion.

7. The method according to claim 6, characterized in that, In step S41, the plurality of second-grain-size sandstone samples are pretreated with dilute hydrochloric acid.

8. The method according to claim 1, characterized in that, Step S30 also includes the following steps: S31. The plurality of sandstone samples of the first particle size are compressed into a plurality of compressed samples; S32. The contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers, and illite / montmorillonite mixed layers in the multiple pressed samples are measured repeatedly, and the average value of the multiple repeated measurements is taken 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.

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