Method for determining producing area of sandstone

Abstract

The embodiment of the invention relates to the field of testing or analyzing materials by means of measuring chemical or physical properties of the materials, in particular to a method for determining the producing area of sandstone. The method comprises the following steps: acquiring a plurality of sandstone samples of which the producing areas are to be determined and a plurality of control samples of which the producing areas are known, and determining illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layers and illite / montmorillonite mixed layer contents in the sandstone samples and the control samples; determining chemical weathering indexes of the sandstone sample and the control sample; the method comprises the following steps: determining illite, montmorillonite, chlorite, kaolinite, a chlorite / montmorillonite mixed layer and mineral components of the illite / montmorillonite mixed layer related to the production place; and determining the producing areas of the plurality of sandstone samples of which the producing areas are to be determined according to the contents of the mineral components related to the producing areas and the chemical weathering indexes in the control samples and the sandstone samples. The method provided by the embodiment of the invention can effectively and accurately determine the producing area of the sandstone sample of which the producing area is to be determined.

Description

TECHNICAL FIELD

[0001] 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 in particular to a method for determining the provenance of sandstone. BACKGROUND

[0002] The statements herein are merely provided for background information of the present application and do not necessarily constitute the prior art.

[0003] Sandstone is a common sedimentary rock, which is widely distributed on the earth's surface. The provenance of sandstone is closely related to the geological history and depositional environment. By determining the provenance of sandstone, it is beneficial to reconstruct the paleogeographic environment, the evolution history of sedimentary basin and the process of tectonic movement; sandstone usually contains important mineral resources such as uranium and copper, and determining the provenance of sandstone is also beneficial to determine the distribution rule of mineral resources. Therefore, it is necessary to study the technology for determining the provenance of sandstone.

[0004] At present, the technology for determining the provenance of sandstone still has many limitations. SUMMARY

[0005] A brief summary of the application is presented in the following to provide a basic understanding of some aspects of the application. It should be understood that this summary is not an exhaustive overview of the application. It is not intended to identify key or important parts of the application nor is it intended to limit the scope of the application. Its purpose is merely to present some concepts in a simplified form as a prelude to the more detailed description of a later discussion.

[0006] In view of the above problems, embodiments of the present application provide a method for determining the provenance of sandstone.

[0007] The method comprises the following steps: S10, obtaining a plurality of sandstone samples of to-be-determined provenances; S20, preparing a plurality of sandstone samples of a first particle size and a plurality of sandstone samples of a second particle size from the plurality of sandstone samples, the first particle size being greater than the second particle size; S30, determining 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 particle size; S40, determining the contents of K2O, Na2O, CaO and Al2O3 in the plurality of sandstone samples of the second particle size; S50, determining a chemical weathering index of the plurality of sandstone samples of the second particle size according to the contents of K2O, Na2O, CaO and Al2O3 in the plurality of sandstone samples of the second particle size determined in the step S40; S60, obtaining a plurality of control samples of known provenances, and performing the steps S20-S50 on the plurality of control samples; S70, determining mineral composition components related to the provenances of the sandstone from illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer in the plurality of control samples according to the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer and the chemical weathering index of the plurality of control samples; S80, determining the provenances of the plurality of sandstone samples of to-be-determined provenances according to the contents of the mineral composition components related to the provenances of the sandstone in the plurality of control samples, the chemical weathering index of the plurality of control samples, the provenances of the plurality of control samples, the contents of the mineral composition components related to the provenances of the sandstone in the plurality of sandstone samples and the chemical weathering index of the plurality of sandstone samples.

[0008] The method provided in the embodiments of the present application determines the mineral components related to the origin of the sandstone in the illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer of the sandstone, and determines the origin of multiple sandstone samples to be determined based on the content of the mineral components related to the origin of the sandstone in multiple control samples, the chemical weathering index of the multiple control samples, the origin of the multiple control samples, the content of the mineral components related to the origin of the sandstone in the multiple sandstone samples, and the chemical weathering index of the multiple sandstone samples. This method can not only effectively determine the origin of the sandstone samples to be determined, but also reduce the complexity of determining the origin of the sandstone samples to be determined, improve the determination efficiency, and also improve the accuracy of the determined origin of the sandstone samples. This is conducive to providing reliable and accurate technical support for geological research and resource exploration; at the same time, by preparing the obtained sandstone samples and control samples into samples of the first particle size and samples of the second particle size, the processing work of the obtained sandstone samples and the obtained control samples can be minimized, the intermediate links can be reduced, and the probability of contamination of the samples by the intermediate links is reduced, which is conducive to accurately measuring the above-mentioned content and chemical weathering index of the samples; and, by preparing the obtained sandstone samples and control samples into samples of the first particle size and samples of the second particle size, it is convenient to measure the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer in the obtained samples, as well as the contents of K2O, Na2O, CaO and Al2O3 in the samples. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0010] Figure 1 It is a flowchart of the method provided in the embodiment of the present application.

[0011] It should be noted that the drawings are not necessarily drawn to scale, but are merely shown in a schematic manner that does not affect the reader's understanding. DETAILED DESCRIPTION

[0012] Exemplary embodiments of the present application will be described herein below with reference to the accompanying drawings. In the description, specific terminology and descriptions are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to those skilled in the art that embodiments of the present application can be practiced without using the specific detailed

[0013] It is also to be understood that not all features of a practical implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made in order to achieve the developer's specific goals, such as compliance with system- and business-related constraints, which can vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill in the art having the benefit of this disclosure.

[0014] In the related art, the origin of sandstone is determined by using chemical composition and mineral composition of sandstone, but there is a problem that the origin of sandstone cannot be effectively determined and the determination accuracy is low in determining the origin of sandstone.

[0015] In view of the above problem, embodiments of the present application provide a method for determining the origin of sandstone.

[0016] Referring to Figure 1 , Figure 1The method provided by the embodiment of the present application is a flowchart of the method, which can include the following steps: S10, obtaining a plurality of sandstone samples of unknown provenance; S20, preparing the plurality of sandstone samples into a plurality of sandstone samples of a first particle size and a plurality of sandstone samples of a second particle size, the first particle size being greater than the second particle size; S30, determining 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 particle size; S40, determining the contents of K2O, Na2O, CaO and Al2O3 in the plurality of sandstone samples of the second particle size; S50, determining the chemical weathering index of the plurality of sandstone samples of the second particle size according to the contents of K2O, Na2O, CaO and Al2O3 in the plurality of sandstone samples of the second particle size determined in the step S40; S60, obtaining a plurality of control samples of known provenance, and performing the steps S20-S50 on the plurality of control samples; S70, determining the mineral composition related to the provenance of sandstone of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer in the plurality of control samples according to the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer and the chemical weathering index of the plurality of control samples; S80, determining the provenance of the plurality of sandstone samples of unknown provenance according to the contents of the mineral composition related to the provenance of sandstone in the plurality of control samples, the chemical weathering index of the plurality of control samples, the provenance of the plurality of control samples, the contents of the mineral composition related to the provenance of sandstone in the plurality of sandstone samples and the chemical weathering index of the plurality of sandstone samples.

[0017] The method provided by the embodiments of the present application can effectively determine the provenance of the to-be-determined sandstone sample, reduce the complexity of determining the provenance of the to-be-determined sandstone sample, improve the determination efficiency, improve the accuracy of the determined provenance of the sandstone sample, and thus provide reliable and accurate technical support for geological research and resource exploration. Meanwhile, the sandstone sample and the control sample are prepared into the sample of the first particle size and the sample of the second particle size, so that the processing work of the obtained sandstone sample and the obtained control sample can be reduced to the greatest extent, the intermediate links are reduced, the pollution probability of the sample caused by the intermediate links is reduced, and the above-mentioned content and the chemical weathering index of the sample can be accurately measured. Furthermore, the sandstone sample and the control sample are prepared into the sample of the first particle size and the sample of the second particle size, so that the content of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer in the obtained sample and the content of K2O, Na2O, CaO and Al2O3 in the sample can be measured.

[0018] In some embodiments, the first particle size can be 60-80 mesh, so as to facilitate the measurement of the content of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer in the sample of the first particle size. For example, the first particle size can be 70 mesh.

[0019] In some embodiments, the second particle size can be 200 mesh, so as to facilitate the measurement of the content of K2O, Na2O, CaO and Al2O3 in the sample of the second particle size.

[0020] In some embodiments, in the step S20, each sandstone sample can be processed to prepare one sandstone sample of the first particle size and one sandstone sample of the second particle size, that is, the number of the sandstone sample of the first particle size and the number of the sandstone sample of the second particle size are the same as the number of the obtained sandstone sample. In the step S60, the obtained control sample is processed in the same manner.

[0021] In some embodiments, in the step S60, at least three control samples are obtained from each production area when the plurality of control samples are obtained. In such embodiments, at least three control samples are obtained from each production area so as to avoid random errors in subsequent processes and improve the accuracy of the subsequent determination of the content and chemical weathering index.

[0022] In some embodiments, in the step S70, the following steps can also be included: S71, determining the correlation coefficient between the content of one of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer and the content of other components in the plurality of control samples and the chemical weathering index of the plurality of control samples; S72, determining the component related to the production area of sandstone from illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer according to the correlation coefficient determined in the step S71. In such embodiments, by determining the correlation coefficient, the mineral composition component related to the production area of sandstone in the control sample can be accurately determined, so as to eliminate the mineral composition component irrelevant to the production area of sandstone, reduce the factors to be considered when determining the production area of the to-be-determined sandstone sample, thereby reducing the complexity and improving the determination efficiency when determining the production area of the to-be-determined sandstone sample.

[0023] In some embodiments, in the step S72, the following steps can also be included: determining that the correlation coefficient determined in the step S71 is less than a preset correlation coefficient, and determining that the component corresponding to the correlation coefficient determined in the step S71 is irrelevant to the production area of sandstone. In such embodiments, by determining the preset correlation coefficient capable of representing the degree of correlation and comparing the correlation coefficient with the preset correlation coefficient, the degree of correlation between the component corresponding to the correlation coefficient less than the preset correlation coefficient and the production area of sandstone is determined, which is beneficial to accurately eliminating the component irrelevant to the production area of sandstone.

[0024] In some embodiments, in the step S72, the following steps can also be included: determining that the correlation coefficient determined in the step S71 is greater than or equal to a preset correlation coefficient, and determining that the component corresponding to the correlation coefficient determined in the step S71 is relevant to the production area of sandstone. In such embodiments, by determining the preset correlation coefficient capable of representing the degree of correlation and comparing the correlation coefficient with the preset correlation coefficient, the degree of correlation between the component corresponding to the correlation coefficient greater than the preset correlation coefficient and the production area of sandstone is determined, which is beneficial to accurately determining the component relevant to the production area of sandstone.

[0025] In some embodiments, the preset correlation coefficient can be 0.1, so as to eliminate the irrelevant component and reduce the complexity of the subsequent determination process and improve the determination efficiency.

[0026] In some embodiments, in the step S71, the following steps can also be included: S711, determining a first vector composed of the illite content in the plurality of control samples according to the illite content in the plurality of control samples; S712, determining a plurality of second vectors composed of the montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer content in the plurality of control samples and a third vector composed of the chemical weathering index of the plurality of control samples according to the montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer content in the plurality of control samples and the chemical weathering index of the plurality of control samples; S713, determining a matrix composed of the first vector, the plurality of second vectors and the third vector according to the first vector determined in the step S711 and the second vector and the third vector determined in the step S712; S714, determining a correlation coefficient matrix of the matrix according to the matrix determined in the step S713; S715, determining a correlation coefficient according to the correlation coefficient matrix determined in the step S714.

[0027] Specifically, in determining the correlation coefficient between the illite and the montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer and chemical weathering index in the plurality of control samples, the first vector composed of the illite content in the plurality of control samples is V1=[illite1, illite2, illite3, …, illite m ] T ,

[0028] V1 is the first vector, illite1 to illite m represent the illite content in the plurality of control samples, m is the number of control samples; the plurality of second vectors composed of the montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer content in the plurality of control samples are

[0029] V2=[x1, x2, x3, …, x m T ,

[0030] V2 is the second vector, x represents one of the montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer, x1 to x m represent the content of the component represented by x in the plurality of control samples; the third vector composed of the chemical weathering index of the plurality of control samples is

[0031] V3=[X1, X2, X3, …, X m T ,

[0032] V3 is the third vector, X1 to X m ​​represents the chemical weathering index of the plurality of control samples; the matrix composed of the first vector V1, the plurality of second vectors V2 and the third vector V3 is

[0033]

[0034] Z is a matrix composed of the first vector V1, the plurality of second vectors V2 and the third vector V3; according to the matrix Z, a correlation coefficient matrix R of the matrix Z and an inverse matrix R of the correlation coefficient matrix R are calculated -1 ; the correlation coefficient between illite and montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer and the chemical weathering index conforms to the following relationship:

[0035]

[0036] A 伊利石 is the correlation coefficient between illite and montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer and the chemical weathering index, (R -1 ) ii is the inverse matrix R -1 corresponding to the diagonal element of illite. The determination process of the correlation coefficient between the content of one of the components of montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer in the plurality of control samples and the content of other components and the chemical weathering index of the plurality of control samples is the same as above.

[0037] In some embodiments, in the step S80, the following steps can also be included: S81, determining that the characteristic value related to the origin of sandstone, the content of mineral composition related to the origin of sandstone and the chemical weathering index of sandstone conform to the following relationship:

[0038] Y = ∑aC i +bX+d,

[0039] In the formula, Y is the characteristic value related to the origin of sandstone, a, b and d are parameters, C i is the content of mineral composition related to the origin of sandstone, i is the number of mineral composition related to the origin of sandstone, and X is the chemical weathering index of sandstone; S82, determining a, b and d according to the origin of the plurality of control samples, the content of mineral composition related to the origin of sandstone determined in the step S72 and the chemical weathering index of the plurality of control samples; S83, determining the characteristic value Y according to the content of mineral composition related to the origin of sandstone in the plurality of sandstone samples and the chemical weathering index of the plurality of sandstone samples; S84, determining the origin of the plurality of sandstone samples with the origin to be determined according to the characteristic value Y determined in the step S83. In such embodiments, the above steps are beneficial to accurately determine the origin of the plurality of sandstone samples with the origin to be determined.

[0040] In some embodiments, in the step S81, the following step can also be included: determining, according to the provenance of the plurality of control samples, the characteristic value related to each provenance, the content of the mineral composition component related to the provenance of the sandstone, and the chemical weathering index of the sandstone, and the relationship formula to which the characteristic value related to each provenance, the content of the mineral composition component related to the provenance of the sandstone, and the chemical weathering index of the sandstone conform. Since the relationship formula to which the characteristic value related to each provenance, the content of the mineral composition component related to the provenance of the sandstone, and the chemical weathering index of the sandstone conform is different in different provenances, the embodiments of the present application can comprehensively reflect the characteristics of each provenance by respectively determining the characteristic value related to each provenance, the content of the mineral composition component related to the provenance of the sandstone, and the relationship formula to which the chemical weathering index of the sandstone conforms, thereby facilitating to improve the efficiency and accuracy when subsequently determining the provenance of the plurality of sandstone samples to be determined.

[0041] In some embodiments, in the step S82, the following steps can also be included: S821, determining, according to the content of the mineral composition component related to the provenance of the sandstone in the plurality of control samples of the same provenance and the chemical weathering index of the plurality of control samples of the same provenance, the mean value of the content of the mineral composition component related to the provenance of the sandstone in the provenance sandstone and the mean value of the chemical weathering index of the provenance sandstone; S822, determining, according to the content of the mineral composition component related to the provenance of the sandstone in each control sample and the mean value of the content determined in the step S821, the difference between the content of the mineral composition component related to the provenance of the sandstone in each control sample and the mean value determined in the step S821; S823, determining, according to the chemical weathering index of each control sample and the mean value of the chemical weathering index determined in the step S821, the difference between the chemical weathering index of each control sample and the mean value of the chemical weathering index determined in the step S821; S824, determining, according to the difference determined in the step S822 and the difference determined in the step S823, the difference value between the plurality of control samples of the same provenance; S825, determining the mean value of the content of the mineral composition component related to the provenance of the sandstone in all control samples and the mean value of the chemical weathering index of all control samples; S826, determining, according to the mean value determined in the step S825, the difference value between the plurality of control samples of different provenances; S827, determining a, b, and d according to the difference value determined in the step S824 and the difference value determined in the step S826. In such embodiments, by determining a, b, and d according to the difference value between the sandstone samples of the same provenance and the difference value between the sandstone samples of different provenances, the accuracy and reliability of the determined a, b, and d can be improved, thereby the accuracy and reliability of the plurality of characteristic values Y determined in the step S83 can be improved, and the accuracy and reliability of the determined sandstone samples can be facilitated to be ensured.

[0042] Specifically, the difference value determined in the step S824, the difference value determined in the step S822, and the difference value determined in the step S823 satisfy the following relationship formula

[0043]

[0044] wherein W is the difference value determined in S824, u represents a vector composed of the difference values determined in S822 or the difference values determined in S823, u T represents a transposed vector of the matrix u, n represents the number of the kinds of the mineral composition components related to the origin of the sandstone in the control samples, and i is a summation index.

[0045] Specifically, the mean of the contents of the mineral composition components related to the origin of the sandstone in all the control samples, the mean of the chemical weathering indexes of all the control samples, and the difference value determined in S826 satisfy the following relationship

[0046]

[0047] wherein B is the difference value determined in S826, is a vector composed of the mean of the contents of the mineral composition components related to the origin of the sandstone in all the control samples or the mean of the chemical weathering indexes of all the control samples, is a transposed vector of the vector , and g is a summation index.

[0048] Specifically, the difference value determined in S824 and the difference value determined in S826 satisfy the following relationship

[0049] W -1 BV = λV,

[0050] wherein V is an eigenvector, and λ is an intermediate variable used for determining a, b, and d; after the intermediate variable λ is determined according to the difference value W and the difference value B determined above, a, b, and d are determined according to the intermediate variable λ.

[0051] In some embodiments, in S83, the following steps can also be included: determining a plurality of eigenvalues Y according to the contents of the mineral composition components related to the origin of the sandstone in each sandstone sample, the chemical weathering indexes of each sandstone sample, and a plurality of relationship formulas determined in S81. In such embodiments, the plurality of eigenvalues Y are determined so as to facilitate determining the origin of the to-be-determined sandstone sample according to the plurality of eigenvalues Y, which is conducive to improving the accuracy of determining the origin of the to-be-determined sandstone sample.

[0052] In some embodiments, in S84, the following steps can also be included: S841, determining the maximum eigenvalue Y max among the plurality of eigenvalues Y max determined in S83 according to the plurality of eigenvalues Y maxthe relationship formula; S843, determining the provenance of the control sample corresponding to the determined relationship formula, and further determining the provenance of the sandstone sample to be determined. In such embodiments, by determining the maximum characteristic value Y max from the plurality of characteristic values Y to determine the relationship formula that is most consistent with the content of the mineral composition ingredient related to the provenance of the sandstone in the sandstone sample and the chemical weathering index of the sandstone sample, and further determining the provenance of the sandstone sample to be determined according to the provenance of the control sample corresponding to the most consistent relationship formula, which is conducive to improving the efficiency of determining the provenance of the sandstone sample to be determined and improving the accuracy of determining the provenance of the sandstone sample to be determined.

[0053] In some embodiments, before the step S70, the method further comprises: S700, correcting the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the plurality of first-granularity sandstone samples determined in the step S30. In the step S71, the distance between any two sandstone samples in the plurality of sandstone samples is determined according to the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer corrected in the step S700 and the chemical weathering index determined in the step S50. In such embodiments, the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the plurality of first-granularity sandstone samples are corrected first, and then the distance between any two sandstone samples in the plurality of sandstone samples is determined according to the corrected contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer, which can reduce the complexity of the process of determining the distance between any two sandstone samples in the plurality of sandstone samples and simplify the operation of determining the distance between any two sandstone samples in the plurality of sandstone samples.

[0054] In some embodiments, in the step S40, the method can further comprise the following steps: S41, purifying the plurality of second-granularity sandstone samples to remove calcite in the plurality of second-granularity sandstone samples; S42, digesting the plurality of second-granularity sandstone samples after the purification treatment; and S43, determining the contents of K2O, Na2O, CaO, and Al2O3 in the plurality of second-granularity sandstone samples after the digestion. In such embodiments, the purification treatment of the plurality of second-granularity sandstone samples can remove calcite crystals in the plurality of second-granularity sandstone samples, avoiding the influence of calcite crystals on the measurement of the contents of K2O, Na2O, CaO, and Al2O3; at the same time, the plurality of second-granularity sandstone samples after the purification treatment are digested to facilitate the measurement of the contents of K2O, Na2O, CaO, and Al2O3.

[0055] In some embodiments, in the step S41, the plurality of sandstone samples of the second particle size can be pretreated by using dilute hydrochloric acid. In such embodiments, the plurality of sandstone samples of the second particle size are pretreated by using dilute hydrochloric acid, which can remove calcite crystals in the plurality of sandstone samples of the second particle size, while avoiding affecting the measurement of the contents of K2O, Na2O, CaO and Al2O3 in the plurality of second particle sizes, and is conducive to ensuring the accuracy of the measured contents of K2O, Na2O, CaO and Al2O3.

[0056] In some embodiments, in the step S42, the plurality of pretreated sandstone samples of the second particle size can be digested by using a mixed acid composed of HNO3-HF-HClO4. In such embodiments, the plurality of pretreated sandstone samples of the second particle size are digested by using the plurality of pretreated sandstone samples of the second particle size, which can ensure the high purity of the reagents used for digestion, avoid the introduction of impurities in the digestion process, and thus avoid affecting the accuracy of the measured contents of K2O, Na2O, CaO and Al2O3.

[0057] In some embodiments, in the step S50, the method can further include: determining that the content of CaO is greater than the content of Na2O, and determining the chemical weathering index of the plurality of sandstone samples of the second particle size according to the contents of K2O, Na2O and Al2O3. During the digestion process, CaO and Na2O can interfere with each other, resulting in inaccurate measured contents of CaO or Na2O. The embodiments of the present application can avoid the influence of inaccurate measured contents of CaO on the determined chemical weathering index, so as to ensure the accuracy of the determined chemical weathering index, by determining that the content of CaO is greater than the content of Na2O, and determining the chemical weathering index according to the contents of K2O, Na2O and Al2O3.

[0058] In some embodiments, the chemical weathering index, the content of K2O, the content of Na2O and the content of Al2O3 of the plurality of sandstone samples of the second particle size satisfy the following relationship:

[0059] Z = 2 * Al2O3 / (Al2O3 + 2 * Na2O + K2O) * 100,

[0060] In the formula, Z represents the chemical weathering index of the plurality of sandstone samples of the second particle size, Al2O3 represents the content of Al2O3, Na2O represents the content of Na2O, and K2O represents the content of K2O. In such embodiments, according to the above relationship, the chemical weathering index of the plurality of sandstone samples of the second particle size can be accurately determined.

[0061] In some embodiments, in the step S50, the method can further include: determining that the CaO content is less than or equal to the Na2O content, and determining the chemical weathering index of the sandstone samples of the plurality of second particle sizes according to the K2O content, the Na2O content, the CaO content, and the Al2O3 content. During the digestion process, CaO and Na2O interfere with each other, resulting in inaccurate measured CaO content or Na2O content. In the embodiments of the present application, by determining that the CaO content is less than or equal to the Na2O content, and determining the chemical weathering index according to the K2O content, the Na2O content, the CaO content, and the Al2O3 content, the influence on the determined chemical weathering index can be avoided, so as to ensure the accuracy of the determined chemical weathering index. In some embodiments, the chemical weathering index, the K2O content, the Na2O content, and the Al2O3 content of the sandstone samples of the plurality of second particle sizes satisfy the following relationship:

[0062] Z = 2 x Al2O3 / (Al2O3 + CaO + Na2O + K2O) x 100,

[0063] In the formula, Z represents the chemical weathering index of the sandstone samples of the plurality of second particle sizes, Al2O3 represents the Al2O3 content, CaO represents the CaO content, Na2O represents the Na2O content, and K2O represents the K2O content. In such embodiments, according to the above relationship, the chemical weathering index of the sandstone samples of the plurality of second particle sizes can be accurately determined.

[0064] In some embodiments, in the step S30, the method can further include the following steps: S31, pressing the sandstone samples of the plurality of first particle sizes into a plurality of pressed samples; and S32, repeatedly measuring the illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer contents in the plurality of pressed samples for multiple times, and taking the average value of the multiple repeated measurements as the illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer contents in the sandstone samples of the plurality of first particle sizes. In such embodiments, the sandstone samples of the first particle size are pressed into pressed samples, which can reduce the voids in the samples, ensure the measurement accuracy, and be conducive to accurately measuring the contents and improving the accuracy of the measured illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer contents; and the pressed samples are repeatedly measured for multiple times, and the average value of the multiple repeated measurements is taken as the illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer contents in the sandstone samples of the plurality of first particle sizes, which can avoid accidental errors during measurement, and also be conducive to improving the accuracy of the measured illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer contents.

[0065] In some embodiments, in the step S31, the multiple sandstone samples of the first granularity can be pressed into multiple tablet samples by using a tablet press. Specifically, the pressure of the tablet press can be set to a maximum of 20 tons, and the constant pressure pressing can be performed for 1 minute.

[0066] In the embodiments of the present application, by pressing the sandstone samples of the first granularity into tablet samples under constant pressure, the internal structure of the tablet samples obtained by pressing can be ensured to be uniform, and the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer can be accurately measured.

[0067] In some embodiments, in the step S32, the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer in the tablet samples can be measured by using X-ray. Specifically, the X-ray tube voltage can be set to a maximum of 50 kV, the current can be set to a maximum of 100 mA, and the detection time can be set to 30 seconds.

[0068] In some embodiments, in the step S32, each tablet sample can be measured for 3-10 times, and the average value of the 3-10 measurements can be taken as the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer in the sandstone samples of the first granularity. For example, each tablet sample can be measured for 5 times.

[0069] In some embodiments, before the step S31, the method can further include: S300, pretreating the multiple sandstone samples of the first granularity with H2O2 or dilute acetic acid, and extracting clay particles with a particle size less than 2 μm by using a sedimentation method or a centrifugal method. In the step S31, the clay particles extracted in the step S300 are pressed into tablet samples. In such embodiments, by treating the multiple sandstone samples of the first granularity with H2O2 or dilute acetic acid, the sandstone samples of the first granularity can be converted into clay particles, which facilitates the subsequent extraction of clay particles with a particle size less than 2 μm; at the same time, by treating the multiple sandstone samples of the first granularity with H2O2 or dilute acetic acid, the reagents added can not affect the illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer in the sandstone samples of the first granularity, which facilitates the accurate measurement of the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer in the sandstone samples of the first granularity; and the extraction of clay particles with a particle size less than 2 μm facilitates the pressing of the clay particles into tablet samples in the step S31.

[0070] The process of determining the origin of sandstone by the method provided by the embodiment of the present application is described below. The samples of known origin are 21 samples of Cretaceous sandstone, and the 21 samples are respectively from Songliao Basin, Erenhot Basin, Ordos Basin and Junggar Basin. Specifically, the samples from Songliao Basin are 5 samples, the samples from Erenhot Basin are 4 samples, the samples from Ordos Basin are 8 samples, and the samples from Junggar Basin are 4 samples.

[0071] (1) First, the above 21 samples are respectively made into 21 70-mesh samples and 21 200-mesh samples according to 70 mesh and 200 mesh; then, the 21 70-mesh samples are treated by using dilute acetic acid, and the clay particles with a particle size less than 2 μm after treatment are extracted; then, the clay particles are pressed into 21 tablet samples by using a tablet press under a pressure of 20 tons for 1 minute.

[0072] (2) Then, the X-ray tube voltage is set to the maximum value of 50 kV, the current is set to the maximum value of 100 mA, the detection time is set to 30 seconds, the X-ray emitted by the X-ray tube is used to measure the illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer content in the 21 tablet samples, each tablet sample is measured 5 times, and the average value of the 5 measurements is taken as the illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer content in each 70-mesh sample.

[0073] (3) The 21 200-mesh samples are pretreated by using dilute hydrochloric acid, after the pretreatment is completed, the pretreated 21 200-mesh samples are digested by using HNO3-HF-HClO4, and the K2O, Na2O, CaO and Al2O3 content in the digested 21 200-mesh samples is measured; then, according to the measured K2O, Na2O, CaO and Al2O3 content in the 21 200-mesh samples, the chemical weathering index of each 200-mesh sample is determined.

[0074] Referring to Table 1 below, the illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer and illite / montmorillonite mixed layer content in the 21 70-mesh samples and the chemical weathering index of the 21 200-mesh samples are as shown in Table 1 below.

[0075] Table 1 The above content and chemical weathering index in the 21 samples

[0076]

[0077]

[0078] (4) The measured illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer content in the 17 70-point samples is multiplied by 100 for correction; thereafter, a matrix composed of the corrected illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, illite / montmorillonite mixed layer content and the chemical weathering index of the 21 200-point samples is determined

[0079]

[0080] According to the matrix Z, a correlation coefficient matrix R of the matrix Z and an inverse matrix R of the correlation coefficient matrix R are determined -1 ; according to the inverse matrix R -1 The correlation coefficient is determined, and through calculation, the correlation coefficient between the illite / montmorillonite mixed layer and the illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer in the sandstone and the chemical weathering index is less than 0.1, so the illite / montmorillonite mixed layer is excluded.

[0081] (5) The difference values between the multiple control samples from the Songliao Basin, the difference values between the multiple control samples from the Erenhot Basin, the difference values between the multiple control samples from the Ordos Basin and the difference values between the multiple control samples from the Junggar Basin are calculated respectively, and the difference values between the multiple control samples of the four basins and the multiple control samples of the other three basins are calculated, and according to the above difference values, multiple relationship formulas which are consistent with the characteristic values related to the four basins, the content of the mineral composition components and the chemical weathering index of the sandstone related to the four basins are determined.

[0082] Referring to Table 2 below, the coefficients in the multiple relationship formulas determined are shown in Table 2 below.

[0083] Table 2 Coefficients in the relationship formulas determined

[0084]

[0085] According to the coefficients in Table 2 above, the multiple relationship formulas determined are

[0086] Y1 = -0.119 x Ill + 5.244 x Chl + 1.729 x Mnt + 10.305 x Kln + 0.967 x CM + 10.

[0087] 501 x N - 397.264,

[0088] Y2 = -0.022 x Ill + 3.099 x Chl + 1.115 x Mnt + 12.182 x Kln + 0.459 x CM + 9.2

[0089] 12 x N - 297.109,

[0090] Y3 = 0.294 x Ill + 4.756 x Chl + 4.18 x Mnt + 9.802 x Kln + 2.721 x CM + 9.511

[0091] x N - 403.229,

[0092] Y4 = -0.194 x Ill + 4.302 x Chl + 1.382 x Mnt + 14.037 x Kln + 0.649 x CM + 10.

[0093] 181 x N - 367.845;

[0094] In the above formula, Y1, Y2, Y3 and Y4 are the characteristic values related to Songliao Basin, the characteristic values related to Erlian Basin, the characteristic values related to Ordos Basin and the characteristic values related to Junggar Basin respectively, Ill represents illite content, Chl represents chlorite content, Mnt represents montmorillonite content, Kln represents kaolinite content, CM represents chlorite / montmorillonite mixed layer content, and N represents chemical weathering index.

[0095] (6) The illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer content and chemical weathering index in the sandstone sample of the to-be-determined origin are substituted into the above four relationship formulas to obtain four Y values, and according to the origin corresponding to the largest Y value in the four Y values, the origin of the sandstone sample of the to-be-determined origin is determined.

[0096] For the embodiments of the present application, it also needs to be explained that the embodiments and the features in the embodiments of the present application can be combined with each other to obtain new embodiments without conflict.

[0097] The above is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto, and the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for determining the origin of sandstone, characterized in that: The method comprises the following steps: S10, obtaining multiple sandstone samples of to-be-determined origin; S20, preparing the plurality of sandstone samples into a plurality of sandstone samples with a first particle size and a plurality of sandstone samples with a second particle size, wherein the first particle size is greater than the second particle size; S30, determining 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 particle size; S40, determining the contents of K2O, Na2O, CaO, and Al2O3 in the plurality of sandstone samples of the second particle size; S50, determining the chemical weathering index of the plurality of sandstone samples of the second particle size according to the K2O, Na2O, CaO and Al2O3 contents in the plurality of sandstone samples of the second particle size determined in step S40; S60, obtaining a plurality of control samples of known origin, and performing steps S20-S50 on the plurality of control samples; S70. Determine, based on the contents of illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the plurality of control samples and the chemical weathering index of the plurality of control samples, the mineral compositions of the illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the sandstone that are related to the origin of the sandstone; S80. Determine the origin of the multiple sandstone samples to be determined based on the content of mineral components related to the origin of the sandstone in the multiple control samples, the chemical weathering index of the multiple control samples, the origin of the multiple control samples, the content of mineral components related to the origin of the sandstone in the multiple sandstone samples, and the chemical weathering index of the multiple sandstone samples.

2. The method according to claim 1, characterized in that In step S70, the following steps are also included: S71. Determine the correlation coefficient between the content of one component among illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer in the plurality of control samples and the content of the other components and the chemical weathering index of the plurality of control samples; S72. Determine the components related to the origin of the sandstone in illite, montmorillonite, chlorite, kaolinite, chlorite / montmorillonite mixed layer, and illite / montmorillonite mixed layer based on the correlation coefficient determined in step S71.

3. The method according to claim 2, characterized in that In step S72, the following steps are also included: It is determined that the correlation coefficient determined in step S71 is less than a preset correlation coefficient, and it is determined that the component corresponding to the correlation coefficient determined in step S71 is not correlated with the origin of the sandstone.

4. The method according to claim 2, characterized in that In step S72, the following steps are also included: It is determined that the correlation coefficient determined in step S71 is greater than or equal to a preset correlation coefficient, and it is determined that the component corresponding to the correlation coefficient determined in step S71 is related to the origin of the sandstone.

5. The method according to claim 2, characterized in that In step S80, the following steps are also included: S81. Determine that the characteristic values ​​associated with the origin of the sandstone, the content of the mineral components associated with the origin of the sandstone, and the chemical weathering index of the sandstone conform to the following relationship: Y=∑aC i +bX+d, Where Y is the characteristic value related to the origin of sandstone, a, b, d are parameters, C i is the content of mineral components related to the origin of sandstone, X is the chemical weathering index of sandstone; S82, determining a, b, and d according to the origins of the plurality of control samples, the contents of the mineral components related to the origins of the sandstone determined in step S72, and the chemical weathering index of the plurality of control samples; S83, determining a characteristic value Y based on the contents of mineral components related to the origin of the sandstones in the plurality of sandstone samples and the chemical weathering index of the plurality of sandstone samples; S84. Determine the origins of the plurality of sandstone samples whose origins are to be determined based on the characteristic value Y determined in step S83.

6. The method according to claim 5, characterized in that In step S81, the following steps are also included: According to the origins of the plurality of control samples, a plurality of relationship expressions conforming to the characteristic values ​​associated with each origin, the content of the mineral components associated with the origin of the sandstone, and the chemical weathering index of the sandstone are determined.

7. The method according to claim 6, characterized in that In step S82, the following steps are also included: S821. Determine, based on the contents of the mineral components related to the origin of the sandstone in the plurality of control samples from the same origin and the chemical weathering index of the plurality of control samples from the same origin, an average of the contents of the mineral components related to the origin of the sandstone in the sandstone and an average of the chemical weathering index of the sandstone from the origin; S822. Determine, based on the content of the mineral component related to the origin of the sandstone in each of the control samples and the average of the contents determined in step S821, the difference between the content of the mineral component related to the origin of the sandstone in each of the control samples and the average of the contents determined in step S821; S823. Determine, based on the chemical weathering index of each of the control samples and the average of the chemical weathering indices determined in step S821, the difference between the chemical weathering index of each of the control samples and the average of the chemical weathering indices determined in step S821; S824, determining the difference values ​​between the plurality of control samples from the same origin according to the difference value determined in step S822 and the difference value determined in step S823; S825. Determine the average value of the content of the mineral components related to the origin of the sandstone in all the control samples and the average value of the chemical weathering index of all the control samples; S826. Determine the difference between the plurality of control samples from different origins based on the mean value determined in step S825; S827. Determine a, b, and d based on the difference value determined in step S824 and the difference value determined in step S826.

8. The method according to claim 6, characterized in that In step S83, the following steps are also included: The plurality of characteristic values ​​Y are determined based on the content of the mineral components related to the origin of the sandstone in each sandstone sample, the chemical weathering index of each sandstone sample, and the plurality of relationship expressions determined in step S81.

9. The method according to claim 8, characterized in that In step S84, the following steps are also included: S841, according to the multiple eigenvalues ​​Y determined in step S83, determine the maximum eigenvalue Y max ; S842, according to the maximum eigenvalue Y max , determine the maximum eigenvalue Y max The relationship between S843. Determine the origin of the control sample corresponding to the relationship equation based on the determined relationship equation, and then determine the origin of the sandstone sample whose origin is to be determined.

10. The method according to claim 1, characterized in that In step S40, the following steps are also included: S41, performing purification treatment on the plurality of sandstone samples of the second particle size to remove calcite in the plurality of sandstone samples of the second particle size; S42, digesting and purifying the plurality of sandstone samples of the second particle size; S43. Determine the contents of K2O, Na2O, CaO, and Al2O3 in the plurality of sandstone samples of the second particle size after digestion.

11. The method according to claim 1, wherein In step S50, the following is also included: It is determined that the CaO content is greater than the Na2O content, and the chemical weathering index of the plurality of sandstone samples of the second particle size is determined based on the K2O content, the Na2O content, and the Al2O3 content.

12. The method according to claim 1, characterized in that In step S50, the following is also included: The CaO content is determined to be less than or equal to the Na2O content, and the chemical weathering index of the plurality of sandstone samples of the second particle size is determined based on the K2O content, the Na2O content, the CaO content, and the Al2O3 content.

Images