Tungsten deposit concealed granite body prediction method based on two arbitrarily-inclined mineralized quartz veins

Abstract

The invention discloses a tungsten deposit concealed granite body prediction method based on two mineralized quartz veins with any tendency. The method comprises the following steps: identifying a plurality of mineralized quartz veins with similar trends in a target exploration area; randomly selecting two mineralized quartz veins; measuring the occurrence of the two mineralized quartz veins by using a geological compass; acquiring the altitudes of a dew point A and a dew point B of the two mineralized quartz veins on the earth surface as h1 and h2 respectively; drawing a cross section drawing perpendicular to the mineralized quartz veins, drawing extension lines of the two selected mineralized quartz veins on the cross section drawing along the inclined direction, and taking an intersection point C of the two extension lines as the vertex of the tungsten deposit concealed granite body; and drawing a vertical line I which is vertical to the horizontal plane and passes through the point C on the cross section, intersecting the vertical line I with the horizontal line passing through the point A at a point C'and intersecting with the earth surface at a point C '', and calculating to obtain a depth value CC ''from the position of the vertex of the tungsten deposit concealed granite body to the earth surface. According to the method, accurate prediction of the tungsten deposit hidden granite body is realized, the efficiency is high, and the cost is low.

Description

Technical Field

[0001] The invention belongs to the technical field of mineral exploration, and in particular relates to a method for predicting a concealed granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins. Background Art

[0002] Granite is the parent rock of many tungsten deposits. It refers to rocks that can directly form deposits or provide the main material source for deposits. However, it is often hidden deep underground. Effective prediction of its location and depth is crucial for tungsten exploration and evaluation.

[0003] At present, the main geophysical detection methods used to predict hidden granite bodies are earthquake detection, gravity detection, magnetic detection, electrical detection, etc. However, these methods have the following limitations: (1) High cost. Many geophysical detection technologies require expensive equipment and professional operators, resulting in high overall costs, especially in large-scale or long-term monitoring projects. (2) Environmental impact. Some technologies (such as seismic exploration) may cause a certain degree of damage or interference to the natural environment during implementation, especially in ecologically sensitive areas. (3) Difficulty in data interpretation. The interpretation of geophysical data often requires deep professional knowledge and experience. Due to the complexity of geological conditions, the interpretation of data in different regions may vary greatly, which is prone to misjudgment. (4) Multiple solutions. Geophysical detection results often have multiple solutions, that is, the same observation data may correspond to multiple geological interpretations, which increases the difficulty of correctly identifying geological features.

[0004] There is a method for predicting the hidden granite body in tungsten deposits in the prior art. This method conducts a 1:5000 geological route survey in the mining area and its periphery to search for mineralized quartz veins. It is necessary to select two groups of mineralized quartz veins that are inclined toward each other, and vertically cross the two groups of mineralized quartz veins to make a 1:1000 geological profile. On the geological profile, the two groups of mineralized quartz veins are extended along their inclination to the depth, and the intersection area is circled as the prediction area of ​​the hidden granite body. However, this method has the following problems:

[0005] (1) Limited universality: The above-mentioned existing prediction methods are only applicable to tungsten deposits where two sets of counter-dipping (oppositely inclined) mineralized quartz veins can be found. However, among the mineralized quartz veins found in most tungsten deposits, few have two sets of counter-dipping, and most of the mineralized quartz veins are inclined in the same direction. Therefore, the above-mentioned existing methods cannot be used to predict concealed deposits that only have mineralized quartz veins inclined in the same direction.

[0006] (2) Insufficient accuracy: The existing prediction methods mentioned above can only achieve qualitative prediction effects, that is, roughly circle the area where the concealed granite body may be produced, but cannot achieve accurate quantitative calculation of the location and depth of the concealed granite body.

[0007] (3) High investment cost: The existing forecasting methods mentioned above require the organization of a large number of technical personnel (3 to 5 people), a long cycle (about 30 days), and generally require hundreds of thousands or even millions of dollars. Summary of the invention

[0008] In view of the above analysis, an embodiment of the present invention aims to provide a method for predicting a hidden granite body in a tungsten deposit based on two arbitrarily inclined mineralized quartz veins, so as to solve one or more of the above problems existing in the prior art.

[0009] The object of the present invention is achieved in that:

[0010] A method for predicting the concealed granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins, comprising:

[0011] Step S1: identifying multiple mineralized quartz veins with the same or substantially the same trend in the target exploration area;

[0012] Step S2: randomly selecting two mineralized quartz veins from among all the identified mineralized quartz veins, wherein the selected two mineralized quartz veins are either inclined in the same direction or inclined in opposite directions;

[0013] Step S3: Use a geological compass to measure the occurrence of two mineralized quartz veins, and obtain the dip angles of the two selected mineralized quartz veins as α and β respectively; the outcropping points of the two selected mineralized quartz veins on the surface are point A and point B respectively, and obtain the altitudes of point A and point B as h1 and h2 respectively;

[0014] Step S4: draw a cross-section perpendicular to the mineralized quartz veins, and extend the two selected mineralized quartz veins along the inclined direction on the cross-section, and the intersection C of the two extended lines is the vertex of the hidden granite body of the tungsten deposit;

[0015] Step S5: Draw a vertical line 1 perpendicular to the horizontal plane and passing through point C on the cross section. The vertical line 1 intersects the horizontal line passing through point A at point C′ and intersects the ground surface at point C″. The depth value CC″ of the position of the top of the hidden granite body of the tungsten deposit from the ground surface is calculated.

[0016] Furthermore, two mineralized quartz veins are randomly selected from the remaining mineralized quartz veins in step S2, and multiple depth values ​​CC" are obtained according to the above steps S3 to S5, and the average value of the multiple depth values ​​CC" is used as the final predicted depth of the position of the top of the hidden granite body of the tungsten deposit from the ground surface.

[0017] Furthermore, the step S5 further includes: obtaining the altitude of point C" as h3; and obtaining the depth value CC" of the position of the top of the hidden granite body of the tungsten deposit from the ground surface according to the following formula:

[0018] When h1≤h3, CC"=CC'+C'C";

[0019] When h1>h3, CC〞=CC′-C′C〞;

[0020] In the above formula, CC″ is the distance from point C to point C″, CC′ is the distance from point C to point C′, C′C″ is the distance from point C′ to point C″, and C′C″=|h1-h3|.

[0021] Furthermore, the step S5 also includes: drawing a second perpendicular line through point B and perpendicular to the horizontal plane, wherein the second perpendicular line intersects AC′ at point B′, and obtaining the distance AB′ between the projection points of point A and point B on the plane.

[0022] Furthermore, the step S5 further comprises: connecting point C and point B to obtain line segment CB, and line segment CB or an extension line of CB intersects a horizontal line passing through A at point D;

[0023] The length of CD is obtained, and based on the obtained length of CD, the length of CC' is calculated according to the following formula:

[0024] CC′=CD sin β.

[0025] Furthermore, the length of CD is calculated according to the following formula:

[0026] When two mineralized quartz veins are inclined in the same direction, CD = (AB′±B′D)·sinα / sin(β-α), if h1≤h2, ± is +, if h1>h2, ± is -;

[0027] When two mineralized quartz veins are inclined toward each other, CD = (AB′±B′D)·sinα / sin(180°-β-α). If h1≤h2, ± is -; if h1>h2, ± is +.

[0028] Furthermore, the value of AB′ is measured on a geological plane map, or obtained through actual field measurements.

[0029] Further, the length of B′D is calculated according to the following formula:

[0030] B′D=|h1-h2| / tanβ.

[0031] Furthermore, the length of CC' is calculated according to the following formula:

[0032] When the two mineralized quartz veins are inclined in the same direction and h1≤h2, CC′=(AB′+|h1-h2| / tanβ)·sinα / sin(β-α)·sinβ;

[0033] When the two mineralized quartz veins are inclined in the same direction and h1>h2, CC′=(AB′-|h1-h2| / tanβ)·sinα / sin(β-α)·sinβ;

[0034] When the two mineralized quartz veins are inclined toward each other and h1≤h2, CC′=(AB′-|h1-h2| / tanβ)·sinα / sin(180°-β-α)·sinβ;

[0035] When the two mineralized quartz veins are inclined toward each other and h1>h2, CC′=(AB′+|h1-h2| / tanβ)·sinα / sin(180°-β-α)·sinβ

[0036] In the above formula, AB′ is the horizontal distance between point A and point B; α and β are the inclination angles of the two selected mineralized quartz veins; h1 and h2 are the altitudes of point A and point B respectively.

[0037] Compared with the prior art, the method for predicting the hidden granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins provided by the present invention can achieve at least one of the following beneficial effects:

[0038] 1. By arbitrarily selecting two mineralized quartz veins, it is possible to accurately predict the hidden granite body of the tungsten deposit. The two selected mineralized quartz veins can be inclined in the same direction or inclined in opposite directions. Since the two mineralized quartz veins selected in the prediction method of this application are not restricted by the inclination of the quartz veins, it is theoretically possible to meet the prediction of the hidden granite body of all tungsten deposits with more than two mineralized quartz veins.

[0039] 2. The prediction method of the present application is simple to operate and has low cost. It only requires one technician, one geological compass (for measuring the inclination and dip of mineralized quartz veins), and one GPS (for positioning and measuring altitude). It can be easily completed in 1 to 3 days. The implementation process does not involve environmental damage, and the time, labor and economic costs are extremely low, which can save tens of thousands to tens of millions of dollars. Therefore, the prediction method of the present application can achieve low-cost, accurate quantitative calculation of the location and depth of concealed granite bodies, and is easy to promote and apply.

[0040] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of this specification. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0042] Figure 1 It is the geological plan and exploration line profile of Meiziwo tungsten deposit in Guangdong;

[0043] Figure 2 A cross-sectional schematic diagram for calculating the depth of a concealed granite body provided by the present invention;

[0044] Figure 3 A schematic diagram of the operation flow of the method for predicting the concealed granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins provided by the present invention;

[0045] Figure 4 The geological plan and cross-section of the Pangushan tungsten deposit in Yudu County, Jiangxi Province;

[0046] Figure 5 This is a schematic diagram of the predicted depth of the concealed granite body in the Pangushan tungsten deposit in Yudu County, Jiangxi Province. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0048] To facilitate the understanding of the embodiments of the present application, the following will be further explained with reference to the accompanying drawings, and the embodiments do not constitute a limitation on the embodiments of the present application. In the accompanying drawings, the sizes and relative sizes of the components may be exaggerated for clarity and / or descriptive purposes. When the exemplary embodiments can be implemented differently, the specific process sequence may be performed in a different order than described. For example, two continuously described processes may be performed substantially simultaneously or in an order opposite to the described order. In addition, the same reference numerals represent the same components.

[0049] The terms used here are for the purpose of describing specific embodiments, and are not intended to be restrictive. As used here, unless the context clearly indicates otherwise, the singular forms "one (kind, person)" and "said (the)" are also intended to include plural forms. In addition, when the terms "comprise" and / or "include" and their variations are used in this specification, it is explained that there are stated features, integral bodies, steps, operations, parts, assemblies and / or their groups, but it is not excluded that there are or add one or more other features, integral bodies, steps, operations, parts, assemblies and / or their groups. It should also be noted that, as used here, the terms "substantially", "approximately" and other similar terms are used as approximate terms and not as degree terms, so that they are used to explain the inherent deviations of the measured values, calculated values ​​and / or the values ​​provided that will be recognized by those of ordinary skill in the art.

[0050] Example 1

[0051] The mineralized quartz veins in tungsten deposits are mainly formed by a series of tensional fractures formed under the dynamic action of granite magma emplacement, and then the tungsten-containing hydrothermal fluids from the granite magma fill the tensional fractures. Therefore, the mineralized quartz veins in tungsten deposits are usually produced in groups, such as Figure 1 As shown in the left figure, the strike direction is consistent with the extension direction of the concealed granite body; and because the emplacement power of the granite magma is highly concentrated at the top of the granite magma and gradually diffuses and conducts to the periphery, the mineralized quartz veins converge at the top of the concealed granite body in the cross section and gradually diverge to the shallow part, such as Figure 1 As shown in the right figure in , the convergence points of any two mineralized quartz veins on the cross section and their respective intersections with the horizontal line can form a triangle, and the acute angles between the two mineralized quartz veins and the horizontal line are equal to their respective inclination angles, which provides the basic premise and theoretical basis for the present invention to use the triangle geometry principle for calculation and prediction.

[0052] A specific embodiment of the present invention, as Figures 2 to 3 As shown, a method for predicting a concealed granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins is disclosed. The strikes of the two arbitrarily inclined mineralized quartz veins are similar (i.e., the strikes are consistent or substantially consistent). The prediction method comprises the following steps:

[0053] Step S1: multiple mineralized quartz veins with consistent or substantially consistent strikes are identified in the target exploration area, such as at least two mineralized quartz veins are identified; “substantially consistent” here means that among all the identified mineralized quartz veins, the strikes of any two mineralized quartz veins differ by no more than 10°.

[0054] Step S2: randomly selecting two mineralized quartz veins from all identified mineralized quartz veins, wherein the selected two mineralized quartz veins include two situations of being inclined in the same direction and being inclined in opposite directions, that is, the selected two mineralized quartz veins are either inclined in the same direction or being inclined in opposite directions;

[0055] Step S3: using a geological compass to measure the occurrence (including inclination and dip) of the two mineralized quartz veins, obtaining the dips of the two selected mineralized quartz veins as α and β respectively; the outcropping points of the two selected mineralized quartz veins on the surface are point A and point B respectively, and obtaining the altitudes of point A and point B as h1 and h2 respectively;

[0056] Step S4: draw a cross-section perpendicular to the mineralized quartz veins, and extend the two selected mineralized quartz veins along the inclined direction on the cross-section, and the intersection C of the two extended lines is the vertex of the hidden granite body of the tungsten deposit;

[0057] Step S5: Draw a vertical line 1 perpendicular to the horizontal plane and passing through point C on the cross section. The vertical line 1 intersects the horizontal line passing through point A at point C′ and intersects the ground surface at point C″. The depth value CC″ of the position of the top of the hidden granite body of the tungsten deposit from the ground surface is calculated.

[0058] In this embodiment, step S5 further includes: obtaining the altitude of point C″ as h3; and obtaining the depth value CC″ of the position of the top of the hidden granite body of the tungsten deposit from the ground surface according to the following formula:

[0059] When h1≤h3, CC"=CC'+C'C";

[0060] When h1>h3, CC〞=CC′-C′C〞;

[0061] In the above formula, CC″ is the distance from point C to point C″, CC′ is the distance from point C to point C′, C′C″ is the distance from point C′ to point C″, and C′C″=|h1-h3|.

[0062] In one of the optional implementations, two mineralized quartz veins are arbitrarily selected from the remaining mineralized quartz veins in step S2, and multiple depth values ​​CC" are obtained according to the above steps S3 to S5, and the average value of the multiple depth values ​​CC" is used as the final predicted depth of the position of the vertex of the hidden granite body of the tungsten deposit from the ground surface.

[0063] In this embodiment, step S5 also includes: drawing a second perpendicular line perpendicular to the horizontal plane through point B, wherein the second perpendicular line intersects AC′ at point B′, and obtaining the distance AB′ between the projection points of point A and point B on the plane, wherein the distance AB′ is equal to the horizontal distance AB between point A and point B.

[0064] In this embodiment, step S5 further includes: connecting point C and point B to obtain line segment CB, where line segment CB or an extension of CB intersects with a horizontal line passing through A at point D; calculating the length of CD, and based on the obtained length of CD, calculating the length of CC′ according to the following formula:

[0065] CC′=CD sin β.

[0066] Furthermore, the length of CD is calculated according to the following formula:

[0067] When two mineralized quartz veins are inclined in the same direction, CD = AD·sinα / sin(β-α) = (AB′±B′D)·sinα / sin(β-α), when h1≤h2, ± is +, when h1>h2, ± is -;

[0068] When two mineralized quartz veins are inclined towards each other, CD = AD·sinα / sin(180°-β-α) = (AB′±B′D)·sinα / sin(180°-β-α), when h1≤h2, ± is -, and when h1>h2, ± is +.

[0069] Among them, AB′ is the distance between the projections of point A and point B on the plane. The value of AB′ is measured on the geological plane map or obtained by actual measurement in the field. The calculation formula of B′D is: B′D=|h1-h2| / tanβ.

[0070] Therefore, CC' is calculated according to the following formula:

[0071] When the two mineralized quartz veins are inclined in the same direction and h1≤h2, CC′=AD·sinα / sin(β-α)·sinβ=(AB′+B′D)·sinα / sin(β-α)·sinβ=(AB′+|h1-h2| / tanβ)·sinα / sin(β-α)·sinβ;

[0072] When the two mineralized quartz veins are inclined in the same direction and h1>h2, CC′=AD·sinα / sin(β-α)·sinβ=(AB′-B′D)·sinα / sin(β-α)·sinβ=(AB′-|h1-h2| / tanβ)·sinα / sin(β-α)·sinβ;

[0073] When the two mineralized quartz veins are inclined toward each other and h1≤h2, CC′=AD·sinα / sin(180°-β-α)·sinβ=(AB′-B′D)·sinα / sin(180°-β-α)·sinβ=(AB′-|h1-h2| / tanβ)·sinα / sin(180°-β-α)·sinβ;

[0074] When the two mineralized quartz veins are inclined toward each other and h1>h2, CC′=AD·sinα / sin(β-α)·sinβ=(AB′+B′D)·sinα / sin(180°-β-α)·sinβ=(AB′+|h1-h2| / tanβ)·sinα / sin(180°-β-α)·sinβ

[0075] In the above formula, AB′ is the horizontal distance between point A and point B, which is measured on the geological plane map or obtained by actual measurement; α and β are the inclination angles of the two selected mineralized quartz veins; h1 and h2 are the altitudes of point A and point B respectively.

[0076] For a clearer explanation, the following are the specific operation steps and calculation derivation process of the embodiment of this application:

[0077] [1] In order to make a triangle, two mineralized quartz veins with the same or almost the same strike are randomly selected, and their strike is measured using a geological compass to obtain the dip angles of the two mineralized quartz veins, α and β respectively;

[0078] [2] Make a cross-section, that is, a cross-section perpendicular to the mineralized quartz vein, such as Figure 2 As shown, Figure 2 There are four figures: (a), (b), (c), and (d). The selected mineralized quartz veins may have two situations according to their different inclinations. They can be inclined in the same direction ( Figure 2 (a) and (b) in the figure), or they can be tilted towards each other ( Figure 2 (c) and (d) in Fig. 1); the outcropping points of the two selected mineralized quartz veins on the surface or in the tunnel are A and B respectively, and the altitudes of outcropping point A and outcropping point B are h1 and h2 respectively. When h1≤h2, if Figure 2 As shown in Figure (a) and Figure (c) in the figure; when h1≥h2, as Figure 2 As shown in Figure (b) and Figure (d).

[0079] [3] In order to find the apex of the concealed granite body, that is, the deep convergence point of the two mineralized quartz veins, the two mineralized quartz veins were extended along the inclined direction on the cross-section diagram, and the extended lines intersected at point C. Point C is the apex of the concealed granite body. The angle between the extended lines of the two mineralized quartz veins along the inclined direction is recorded as γ.

[0080] [4] When the two mineralized quartz veins are inclined in the same direction, according to the triangle exterior angle theorem,

[0081] β=α+γ (1)

[0082] When the two mineralized quartz veins are inclined toward each other, according to the triangle interior angle theorem,

[0083] 180°=γ+α+β (2)

[0084] [5] On the cross section, draw a perpendicular line 1 that is perpendicular to the horizontal plane and passes through point C. The perpendicular line 1 intersects the horizontal line passing through A at point C′ and intersects the ground surface at point C″. Point C″ is the plane projection position of the apex of the hidden granite body on the ground surface. The altitude of point C″ is recorded as h3, and CC″ is the depth of the apex of the hidden granite body below the ground surface.

[0085] CC〞=CC′±C′C〞 (3)

[0086] In formula (3), when h1≤h3, ± is +, and when h1>h3, ± is -, that is:

[0087] When h1≤h3, CC〞=CC′+C′C〞; (3-1)

[0088] When h1>h3, CC〞=CC′-C′C〞 (3-2)

[0089] And C′C〞is equal to the height difference between point A and point C〞, that is

[0090] C′C〞=|h1-h3| (4)

[0091] h1 and h3 are obtained through altitude measurement, so in order to calculate CC", CC′ must be calculated first.

[0092] [6] Find CC′:

[0093] Connecting points C and B, line segment CB or its extension intersects the horizontal line through A at point D, then CDC' forms a right triangle, and

[0094] CC′=CD sinβ (5)

[0095] Therefore, we need to find out CD first.

[0096] [7] Request CD:

[0097] In triangle ACD, it is known that ∠DAC=α, ∠ACD=γ. According to the sine theorem (in any plane triangle, the ratio of the sine value of each side to its opposite angle is equal and equal to the diameter of the circumscribed circle), we have

[0098] CD / sinα=AD / sinγ (6)

[0099] When the two mineralized quartz veins are inclined in the same direction ( Figure 2 (a) and (b) in Figure 1), substituting equation (1) into equation (6), we have

[0100] CD=AD·sinα / sin(β-α) (7)

[0101] When the two mineralized quartz veins are inclined toward each other ( Figure 2 (c) and (d) in Figure 1), substitute equation (2) into equation (6):

[0102] CD= AD · sinα / sin(180°-β-α) (8)

[0103] Therefore, AD must be found first.

[0104] [8] Find AD:

[0105] Draw a perpendicular line 2 through point B that is perpendicular to the horizontal plane. The perpendicular line 2 intersects AC' at point B'. Then:

[0106] AD=AB′±B′D (9)

[0107] In formula (9), when the two mineralized quartz veins are inclined in the same direction, if the altitude h2 of point B is equal to or higher than the altitude h1 of point A, then ± takes +( Figure 2 (a) in the figure), otherwise take -( Figure 2 (b) in Figure); When the two mineralized quartz veins are inclined toward each other, if the altitude h2 of point B is equal to or higher than the altitude h1 of point A, take -( Figure 2 (c) in the figure), otherwise take +( Figure 2 (d) in the figure); AB' is the distance between the projection points of point A and point B on the plane, which can be obtained by measuring and converting on the geological plane map, or by actual field measurement; in the right triangle BB'D, ∠BDB'=β, so:

[0108] B′D= BB′ / tanβ (10)

[0109] And BB′ is the height difference between point B and B′, that is

[0110] BB′=|h1-h2| (11)

[0111] Substituting (11) into (10), we have

[0112] B′D=∣h1-h2∣ / tanβ (12)

[0113] Substituting equation (12) into equation (9), we can obtain AD.

[0114] [9] According to the above steps, in the same tungsten deposit, any two other mineralized quartz veins are used to calculate N depth values ​​CC", and then the average value of the N depth values ​​CC" is taken as the final predicted depth of the top of the hidden granite body of the tungsten deposit from the ground surface, so as to further improve the accuracy of the prediction of the position and depth of the hidden granite body of the tungsten deposit.

[0115] Actual engineering case - Taking the prediction and drilling verification of the concealed granite body of Pangushan tungsten deposit in Yudu County, Jiangxi Province as an example

[0116] The Pangushan tungsten deposit is located in Pangushan Town, Yudu County, Jiangxi Province. It is a large tungsten deposit that is well-known both at home and abroad. The ore body of the deposit is produced in the form of mineralized quartz veins, of which more than 300 have industrial mining value. The mineralized quartz veins have basically the same trend, which is northwest-west and generally inclines to the south. The dip angle gradually slows down from south to north. In the cross section, they diverge to the shallow part and converge to the deep part. Figure 4 shown.

[0117] Implementation process and verification:

[0118] [1] Two mineralized quartz veins in the Pangushan tungsten deposit in Yudu County, Jiangxi Province were selected and their dip and inclination were measured using a geological compass. The dips were both 190° and the inclinations were α=67° and β=75° respectively.

[0119] [2] Make a cross-section diagram. The selected mineralized quartz veins are inclined in the same direction. The altitudes of their outcropping points A and B on the surface or in the tunnel are h1 = 1160m and h2 = 1060m respectively, and h1 ≥ h2. Figure 5 As shown;

[0120] [3] The two mineralized quartz veins are extended along the inclined direction in the cross-section. The extended lines of the two mineralized quartz veins usually intersect at point C at the top of the buried granite body, and the acute angle is recorded as γ.

[0121] [4] When the two mineralized quartz veins are inclined in the same direction, according to the triangle exterior angle theorem,

[0122] 75°=67°+γ(1')

[0123] [5] The horizontal line passing through point A and the vertical line passing through point B intersect at point B′ on the section. The horizontal line passing through point A intersects BC at point D. The length of AB′ is measured on the geological plane map. AB′=255m, and the length of B′D is:

[0124] B′D=BB′ / tan75°(2')

[0125] The length of BB' is the height difference between point A and point B, that is:

[0126] BB′=∣1160-1060∣=100m(3')

[0127] Substituting (3') into (2'), we get:

[0128] B′D=∣h1-h2∣ / tanβ=100 / 3.73=26.8m(4')

[0129] [6] Calculate AD length:

[0130] AD=AB′-B′D=255-26.8=228.2m(5')

[0131] In the formula AD = AB′±B′D, the two mineralized quartz veins are inclined in the same direction, and the elevation of point B is lower than that of point A, so the ± sign is -;

[0132] [7] According to the sine theorem (the sine theorem is a basic theorem in trigonometry: in any plane triangle, the ratio of the sine of each side to its opposite angle is equal and equal to the diameter of the circumscribed circle),

[0133] CD / sinα=AD / sinγ (6')

[0134] CD=AD sinα / sinγ (7')

[0135] Since the two mineralized quartz veins are inclined in the same direction, substituting (5') and (1') into (7'), we have:

[0136] CD=228.2×sin67° / sin8°=228.2×0.9205 / 0.1391=1510m(8')

[0137] [8] Draw a perpendicular line through point C on the cross section. It intersects the horizontal line through point A at point C′ and intersects the ground surface at point C″. Measure the altitude of C″ h3 = 850m. Then the length of C′C″ is:

[0138] C′C〞=∣h1-h3∣=∣1160-920∣=240m (9')

[0139] CC′=CD sinβ=1510×sin75°=1510×0.9659=1459m (10')

[0140] [9] After finding CC′ according to (10'), we can find CC〞:

[0141] CC〞=CC′-C′C〞=1459-240=1219m(11')

[0142] In the formula CC"=CC′±C′C", since h1>h3, the ± sign is -.

[0143] Point C" is the plane projection position of the apex of the concealed granite body, and CC" is the depth of the apex of the concealed granite body.

[0144]

[10] According to the above steps, 20 CC" were calculated using other mineralized quartz veins in the tungsten deposit in Yudu County, Jiangxi Province, and then the average value was taken to obtain the average depth value CC" of the top of the concealed granite body = 1242m.

[0145] This result is basically consistent with the depth of the concealed granite body actually revealed by the "Nanling Scientific Drilling SP-NLSD-2" implemented in the Pangushan tungsten deposit in 2012 (1288m, Chen Yuchuan et al., 2021), with a difference of only 46m, which fully demonstrates the reliability of the above calculation and prediction results!

[0146] Compared with the prior art, the method for predicting the hidden granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins provided in this embodiment has at least one of the following beneficial effects:

[0147] 1. By arbitrarily selecting two mineralized quartz veins, it is possible to accurately predict the granite body concealed in the tungsten deposit. The two selected mineralized quartz veins can be inclined in the same direction or inclined in opposite directions. Since the two mineralized quartz veins selected in the prediction method of this application are not restricted by the inclination of the quartz veins, it is applicable to all tungsten deposits in which more than two (including two) mineralized quartz veins have been discovered, and is not restricted by the inclination conditions of the mineralized quartz veins.

[0148] 2. The implementation process of the prediction method of the present application only requires one technician, one geological compass (for measuring the inclination and dip of mineralized quartz veins), and one GPS (for positioning and measuring altitude). It can be easily completed in 1 to 3 days. The implementation process does not involve environmental damage, and the time, labor and economic costs are extremely low, which can save tens of thousands or even tens of millions of dollars, and the results obtained are unique and accurate.

[0149] 3. Since granite-type rare metal ore bodies (rich in tungsten, tin, niobium, tantalum and other metals) are usually developed on the top of concealed granite bodies, such as the tungsten-tin-niobium-tantalum deposits in Limu, Guangxi and Dajishan, Jiangxi, which have such mineralization laws, the method of the present invention can be used to accurately predict concealed granite bodies, which will promote the exploration and discovery of a number of granite-type rare metal ore bodies. Based on 5,000 tons of tungsten ore (small scale) per site and a market price of 140,000 yuan / ton, if 5 sites are discovered, an economic value of 3.5 billion yuan will be generated.

[0150] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the present application in detail. It should be understood that the above description is only the specific implementation method of the present application and is not intended to limit the scope of protection of the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A method for predicting the hidden granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins, characterized in that: include: Step S1: identifying multiple mineralized quartz veins with the same or substantially the same trend in the target exploration area; Step S2: randomly selecting two mineralized quartz veins from among all the identified mineralized quartz veins, wherein the selected two mineralized quartz veins are either inclined in the same direction or inclined in opposite directions; Step S3: Use a geological compass to measure the occurrence of two mineralized quartz veins, and obtain the dip angles of the two selected mineralized quartz veins as α and β respectively; the outcropping points of the two selected mineralized quartz veins on the surface are point A and point B respectively, and obtain the altitudes of point A and point B as h1 and h2 respectively; Step S4: draw a cross-section perpendicular to the mineralized quartz veins, and extend the two selected mineralized quartz veins along the inclined direction on the cross-section, and the intersection C of the two extended lines is the vertex of the hidden granite body of the tungsten deposit; Step S5: Draw a vertical line 1 perpendicular to the horizontal plane and passing through point C on the cross section. The vertical line 1 intersects the horizontal line passing through point A at point C′ and intersects the ground surface at point C″. The depth value CC″ of the position of the top of the hidden granite body of the tungsten deposit from the ground surface is calculated.

2. The method for predicting the hidden granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins according to claim 1 is characterized in that: Among the mineralized quartz veins remaining in step S2, two mineralized quartz veins are randomly selected, and multiple depth values ​​CC" are obtained according to the above steps S3 to S5, and the average value of the multiple depth values ​​CC" is used as the final predicted depth of the position of the top of the hidden granite body of the tungsten deposit from the ground surface.

3. The method for predicting the hidden granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins according to claim 1 or 2, characterized in that: The step S5 also includes: obtaining the altitude of point C" as h3; and obtaining the depth value CC" of the position of the top of the hidden granite body of the tungsten deposit from the ground surface according to the following formula: When h1≤h3, CC"=CC'+C'C"; When h1>h3, CC〞=CC′-C′C〞; In the above formula, CC″ is the distance from point C to point C″, CC′ is the distance from point C to point C′, C′C″ is the distance from point C′ to point C″, and C′C″=|h1-h3|.

4. The method for predicting the hidden granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins according to claim 3 is characterized in that: The step S5 also includes: drawing a second perpendicular line through point B and perpendicular to the horizontal plane, wherein the second perpendicular line intersects AC′ at point B′, and obtaining the distance AB′ between the projection points of point A and point B on the plane.

5. The method for predicting the hidden granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins according to claim 4, characterized in that: The step S5 further comprises: connecting point C and point B to obtain line segment CB, where the line segment CB or an extension of CB intersects with a horizontal line passing through point A at point D; The length of CD is obtained, and based on the obtained length of CD, the length of CC' is calculated according to the following formula: CC′=CD sin β.

6. The method for predicting the hidden granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins according to claim 5, characterized in that: The length of the CD is calculated as follows: When two mineralized quartz veins are inclined in the same direction, CD = (AB′±B′D)·sinα / sin(β-α), if h1≤h2, ± is +, if h1>h2, ± is -; When two mineralized quartz veins are inclined toward each other, CD = (AB′±B′D)·sinα / sin(180°-β-α). If h1≤h2, ± is -; if h1>h2, ± is +.

7. The method for predicting the hidden granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins according to claim 6, characterized in that: The value of AB′ is measured on the geological plane map or obtained through actual measurement in the field.

8. The method for predicting the hidden granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins according to claim 6, characterized in that: Calculate the length of B′D according to the following formula: B′D=|h1-h2| / tanβ.

9. The method for predicting the hidden granite body of a tungsten deposit based on two arbitrarily inclined mineralized quartz veins according to claim 8, characterized in that: The length of CC' is calculated as follows: When the two mineralized quartz veins are inclined in the same direction and h1≤h2, CC′=(AB′+|h1-h2| / tanβ)·sinα / sin(β-α)·sinβ; When the two mineralized quartz veins are inclined in the same direction and h1>h2, CC′=(AB′-|h1-h2| / tanβ)·sinα / sin(β-α)·sinβ; When the two mineralized quartz veins are inclined toward each other and h1≤h2, CC′=(AB′-|h1-h2| / tanβ)·sinα / sin(180°-β-α)·sinβ; When the two mineralized quartz veins are inclined toward each other and h1>h2, CC′=(AB′+|h1-h2| / tanβ)·sinα / sin(180°-β-α)·sinβ In the above formula, AB′ is the horizontal distance between point A and point B; α and β are the inclination angles of the two selected mineralized quartz veins; h1 and h2 are the altitudes of point A and point B respectively.

Images