A method for determining the existence of concealed ore bodies in deep hydrothermal deposits or exploration areas and quickly defining their locations

Abstract

The present invention discloses a method for determining the existence of a hidden ore body in a deep hydrothermal deposit or an exploration area and for quickly delineating its occurrence position. The method is based on the new working idea of ​​"the structural system directly controls the hydrothermal mineralization system, and the exploration information system maps the development position of the hydrothermal mineralization system". Through the fine measurement of the mineralization structure in the hydrothermal deposit or the exploration area and the systematic collection of samples, sample processing and multi-element quantitative analysis, deep mineralization information capture and anomaly delineation, mathematical model construction of characteristic element combination anomalies and determination of the existence of a hidden ore body in deep, the construction of a prospecting model and the delineation of the occurrence position of a hidden ore body in deep, the hydrothermal deposit or the exploration area, the method solves the difficult problem of quickly delineating the occurrence position of ore bodies in the deep and periphery of the hydrothermal deposit or the exploration area, answers the major practical problems of whether there are mines in the deep of the deposit or the exploration area and where to find them, and provides an important basis for prospecting prediction and exploration engineering deployment in the deep of the deposit or the exploration area.

Description

Technical Field

[0001] The invention relates to a method for determining the existence of a concealed ore body in a deep hydrothermal deposit or an exploration area and quickly delineating its occurrence location, and belongs to the field of mineral resource exploration. Background Art

[0002] The exploration and development of mineral resources is related to the national economy, people's livelihood and national security. my country has a large demand for high-quality mineral resources and a high degree of external dependence. In particular, the development of key mineral resources has become the focus of a new round of global resource strategies. To obtain resources from deep is an inevitable and realistic choice to ensure resource security. Looking at the progress of geochemical exploration in the past few decades, we have successively established a prospecting method to delineate hidden ore bodies (beds) based on the abnormal distribution characteristics of primary or secondary halos of metal elements in various ore-bearing media based on the interpretation of the diffusion mechanism of metal elements in the process of hydrothermal mineralization. Important results have been achieved in the shallow prospecting and exploration of different types of metal deposits, showing the strong vitality of geochemical exploration in the prediction of hidden mines. Under normal circumstances, geochemical exploration mainly focuses on the abnormal characteristics of primary or secondary halos of elements to predict shallow ore deposits (bodies), and then discovers ore deposits or ore bodies through prospecting engineering verification and exploration. However, as shallow deposits have been exhausted due to the continuous development of resources, deep prospecting faces severe challenges. Due to the limitations of prospecting engineering and the particularity and continuity of the spatial distribution of ore bodies, it is difficult to capture the information of deep weak mineralization. The anomalies of the inferred ore body location are significantly different from the actual ore body situation, which directly restricts the breakthrough of prospecting in the deep and peripheral or exploration areas of the ore deposit. Therefore, conducting research on the delineation of the location of the hidden ore body in the deep of hydrothermal deposits is undoubtedly of great practical significance for the deployment of mine prospecting and exploration and the increase of reserves and production in the new round of strategic actions for prospecting breakthroughs. Summary of the invention

[0003] The present invention provides a method for determining the existence of concealed ore bodies in the deep part of a hydrothermal deposit or an exploration area and for quickly delineating their occurrence locations. The method is based on the working idea that a structural system directly controls the migration and precipitation of deep ore-forming fluids in a hydrothermal mineralization system and the occurrence of its mineralization, and that an exploration information system maps the development locations of the hydrothermal mineralization system. Through the working procedures of fine measurement of ore-forming structures and systematic sample collection, sample processing and multi-element quantitative analysis, deep mineralization information capture and anomaly delineation, mathematical model construction of characteristic element combination anomalies and determination of the existence of deep concealed ore bodies, construction of a prospecting model and delineation of the occurrence locations of deep concealed ore bodies, the method solves the difficult problem of delineating key prospecting target areas in the deep part of a hydrothermal deposit or an exploration area, solves the major scientific and technological problems of whether there are ores in the deep part of a hydrothermal deposit and where they are located, and provides a basis for prospecting prediction and exploration deployment in the deep part of a deposit or an exploration area.

[0004] The object of the present invention is achieved through the following technical solutions:

[0005] 1. Analysis of ore-controlling structures

[0006] Apply the theory and methods of mine field geomechanics (Sun Jiacong and Han Runsheng, 2016) to precisely measure and analyze the mineralization structures in different middle sections, different veins or profiles in deep tunnels of hydrothermal deposits, identify the types of mineralization structures in the mining area, reveal the laws of structural control of mineralization, establish a model of structural control of rock and mineralization, and infer the prospecting direction in the deep area;

[0007] (2) Structural geochemical mapping

[0008] Sample collection: In deep tunnels, boreholes or exploration work sections of the ore deposit, collect mineralized altered rock samples from fault zones and mineralized alteration and mineralized fracture zones during the mineralization period at a point spacing of 5 to 10 meters. In areas with intense mineralization alteration, increase sampling to a sampling length of 0.5 to 2 meters, and mark the collected samples on the geological profile;

[0009] Sample processing and multi-element analysis: Samples are processed in a pollution-free environment, with a sample size below 200 mesh, and then reduced into a primary sample and a secondary sample; the primary sample is sent to a testing unit with national Class A testing certification for quantitative analysis, and the secondary sample is used as a backup for inspection or retesting, and the test meets the analytical accuracy requirements;

[0010] Analytical data inspection and processing: check the multi-element content of the test and conduct mathematical and statistical analysis (factor analysis, cluster analysis, etc.);

[0011] (3) Capture of deep mineralization information

[0012] By using mathematical statistics or data mining methods, we can obtain the characteristic element combination indicating deep mineralization information, screen out the characteristic element combination indicating mineralization, draw the characteristic element combination anomaly map, and extract the spatial information of mineralization anomaly.

[0013] (4) Construction of mathematical model for characteristic element combination anomaly and determination of the existence of deep concealed ore bodies

[0014] The position of the geological points sampled in different profiles (x) is used as the independent variable and the characteristic element combination anomaly (C j ) is the mathematical model of the function: C j =F(x)=A1×exp(-((x-B1x) / D1) 2 )

[0015] Where: F(x) is the characteristic element combination anomaly, non-dimensional unit; x is the distance, m; A1, B1, D1 are constants; j is the characteristic element combination;

[0016] At the same time, the first derivative function reflecting the tendency of deep concealed ore bodies is obtained:

[0017]

[0018] The mathematical model of the characteristic element combination distribution indicates the existence of a hidden ore body in the depth: ① When F(x) is higher than 2 times the lowest abnormal lower limit, it is a high abnormal value, indicating that there may be a hidden ore body in the depth; when F(x) is far lower than 2 times the lowest abnormal lower limit, it is a low abnormal value, indicating that there is no hidden ore body in the depth or the hidden ore body is located very deep. The lowest abnormal lower limit is the abnormal average value + 2 times the standard deviation.

[0019] (5) Construction of prospecting model and delineation of deep hidden ore bodies

[0020] Analyze and summarize the abnormal characteristics of element combinations at different elevations in the deep ore deposit or exploration area, establish planar and cross-sectional prospecting models of structural characteristic element combination anomalies, draw characteristic element combination anomalies-geological maps, infer the deep ore deposit types and mineral species based on this, delineate deep key prospecting target areas, combine the development characteristics of the ore-controlling structures of the ore deposits and the geological characteristics of the ore deposits, study the distribution laws of the ore-controlling structures and structural ore-controlling types that control the element combination anomalies, determine the mineralization centers and deep mineralization enrichment areas, and delineate the locations where deep hidden ore bodies are located.

[0021] Verification and feedback of exploration engineering: For the location of deep hidden ore bodies, the preferred area for exploration engineering verification is proposed, and then the verification plan, target area verification implementation and information are promptly fed back. Based on the feedback information of engineering verification, the reliability of the delineation of the location of hidden ore bodies is tested. On this basis, the scope of engineering verification of key target areas on the surface is gradually expanded, and the method of delineating the location of deep hidden ore bodies is optimized to achieve progress in deep prospecting.

[0022] Advantages and technical effects of the method of the present invention:

[0023] (1) This method is applicable to the direct delineation of deep concealed ore bodies in hydrothermal deposits in tunnels or semi-exposed or exposed rock areas on the surface; this method is not only applicable to magmatic hydrothermal deposits, such as porphyry copper, molybdenum, gold deposits and medium-high temperature magmatic hydrothermal tungsten, tin, copper, "four rare" minerals and other metal deposits, but also to non-magmatic hydrothermal polymetallic deposits, such as tectonic hydrothermal, metamorphic hydrothermal, composite hydrothermal copper, lead, zinc, gold, iron, "four rare" minerals and other polymetallic deposits;

[0024] (2) The present invention solves the difficult problem of defining key prospecting target areas in the deep and peripheral parts of hydrothermal deposits or in the exploration area under the conditions of limited spatial extension and continuity of prospecting projects and ore bodies, and solves the major problems of whether there are mines in the deep parts and where to find them;

[0025] (3) This method has a wide application range and high accuracy, and can be used to delineate deep ore bodies at a scale of 1:200 to 1:10000;

[0026] (4) This method has clear procedures, strong operability and low working cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the process of the present invention;

[0028] Figure 2 This is the structural ore-controlling model of a certain germanium-rich lead-zinc mining area;

[0029] Figure 3 This is the R-type cluster pedigree diagram of the middle section II of a lead-zinc mining area;

[0030] Figure 4 This is a geological map of the distribution of structural geochemical anomalies in the exploration area of ​​the middle section A of a germanium-rich lead-zinc mining area. In the map: 1. Stratigraphic boundary; 2. Abnormal area; 3. Tunnel; 4. Devonian Haikou Formation (D2h); 5. Devonian Zaige Formation (D3zg); 6. Carboniferous Datang Formation (C1d); 7. Carboniferous Baizuo Formation (C1b); 8. Carboniferous Weining Formation (C2w); 9. Carboniferous Maping Formation (C2m); 10. Lead anomaly contour lines / 10 -6 ; 11. Zinc anomaly contour / 10 -6 ; 12. F3 characteristic element combination (Pb, Zn, Cu, Cd); 13. F6 characteristic element combination (In, Hf, Co, Y); 14. F5 characteristic element combination (MnO, Na2O, T Fe );

[0031] Figure 5 This is a geological map of the distribution of structural geochemical anomalies in the exploration area of ​​the middle section B of a germanium-rich lead-zinc mining area. In the map: 1. Stratigraphic boundary; 2. Abnormal area; 3. Tunnel; 4. Devonian Haikou Formation (D2h); 5. Devonian Zaige Formation (D3zg); 6. Carboniferous Datang Formation (C1d); 7. Carboniferous Baizuo Formation (C1b); 8. Carboniferous Weining Formation (C2w); 9. Carboniferous Maping Formation (C2m); 10. Lead anomaly contour lines / 10 -6 ; 11. Zinc anomaly contour / 10 -6 ; 12. F2 characteristic element combination (Pb, Zn, Cd);

[0032] Figure 6 A comprehensive anomaly prospecting model for element combinations at different elevations in a germanium-rich lead-zinc mining area;

[0033] Figure 7 , Figure 8This is a schematic diagram of the prospecting target area in the A and B exploration areas of the middle section of the II of a germanium-rich lead-zinc mining area. In the figure: 1. Stratigraphic boundary; 2. Fault; 3. Alteration zone boundary; 4. Tunnel; 5. Devonian Zaige Formation (D3zg); 6. Carboniferous Datang Formation (C1d); 7. Carboniferous Baizuo Formation (C1b); 8. Carboniferous Weining Formation (C2w); 9. I medium-fine-grained altered dolomite belt; 10. II pinhole-shaped coarse-grained dolomite belt; 11. III coarse-grained altered dolomite belt; 12. IV dolomitized limestone belt; 13. V calcite-altered fine-grained dolomite belt; 14. VI pyrite-altered belt; 15. Target area;

[0034] Fig. 9 Verification of longitudinal projection map for tunnel gravity, EH4 comprehensive anomaly and deep key target area in a germanium-rich lead-zinc mine area

[0035] Fig.10 The structural control model of a germanium-rich lead-zinc exploration area

[0036] Fig.11 This is the R-type cluster analysis spectrum of the fracture structural rock elements in the ore body distribution area of ​​the middle section Ⅰ of a certain germanium-rich lead-zinc exploration area;

[0037] Fig.12 This is the F2 characteristic element combination anomaly-geological map (F2: Cu, Zn, Ag, Cd, In, Tl, Pb, As, Sb, Hg) of the ore body distribution area in the middle section of a germanium-rich lead-zinc exploration area. DETAILED DESCRIPTION

[0038] The present invention is further described in detail below through drawings and examples, but the protection scope of the present invention is not limited to the contents described above, and the methods in the examples are conventional methods unless otherwise specified.

[0039] Example 1: Delineation of the deep hidden ore deposit area of ​​a germanium-rich lead-zinc deposit in eastern Yunnan

[0040] A germanium-rich lead-zinc deposit is one of the typical representatives of the lead-zinc polymetallic ore cluster in eastern Yunnan. It has high grade (Pb+Zn average about 25%), large reserves (the deposit and ore body can reach large scale); deep ore body extension (up to more than 1600m), strong hydrothermal alteration and obvious mineralization alteration combination zoning law, but the occurrence of deep ore bodies is difficult to predict. Although TEM and other geophysical methods are used, the resistivity and high polarizability anomaly inference interpretation obtained by these methods are highly multi-solution, especially the influence of water-bearing faults, surface high-voltage lines and underground rail facilities in mines, it is difficult to distinguish the distribution characteristics of mineral-induced anomalies or non-ore anomalies in deep concealed ore bodies; it is also difficult to determine the location of deep concealed ore bodies in the interpretation of geochemical anomalies.

[0041] The deposit is a hydrothermal lead-zinc deposit that is clearly controlled by structure, laying the foundation for the delineation of the location of deep concealed ore bodies.

[0042] The specific implementation process of the method of the present invention is as follows: Figure 1 ):

[0043] 1. Analysis of ore-controlling structures

[0044] Applying the theories and methods of mining field geomechanics, the deep tunnels and surface structures in different directions of the mining area were analyzed in detail, and it was identified that the northeast-trending fault during the mineralization period was left-lateral compression-torsion, the north-northwest-trending fault was left-lateral compression-torsion, the nearly east-west-trending fault was right-lateral torsion, and the northwest-trending fault was tension-torsion. After mineralization, the nearly north-south-trending fault cut through the mineralization structure; the northeast-trending left-lateral compression-torsion fault zone directly controlled the distribution of the ore body in the northeast-trending interlayer compression-torsion fault zone and its nearby hydrothermal alteration zone, and the structural control ore model was constructed. Figure 2 shown.

[0045] 2. Structural geochemical mapping

[0046] (1) Based on the exposure of mineralized fault zones and mineralized altered rocks, mineralized altered rock samples were collected at a point spacing of 5 to 10 meters. The sampling was intensified in areas with strong mineralization and alteration. The sampling length was 0.5 to 2 meters, and each sample weighed about 200 grams.

[0047] (2) Under pollution-free conditions, the collected samples are processed and reduced to 200 mesh, divided into primary samples and secondary samples, and the primary samples are sent to a testing center with national Class A testing qualification certification for analysis. The trace and rare earth element contents are tested by ICP-MS (inductively coupled plasma mass spectrometry); the major components of oxides are measured by rock chemical full analysis, and samples with excessively high contents of some mineralizing elements (such as Pb, Zn, etc.) are re-tested by volumetric method; for the analysis of special elements (such as As, Sb, Hg), atomic fluorescence method is used for testing and analysis.

[0048] 3. Capturing deep mineralization information and delineating structural geochemical anomalies

[0049] (1) Effective extraction of deep mineralization information and interpretation of anomalies

[0050] The geochemical data of exploration areas B and A in the middle section of II were unified into one unit (10 -6 ), after rare earth elements were combined into light and heavy rare earths, all data were taken as common logarithms, and R-type factor analysis was performed using Stastistic software (220 samples, 45 variables). When the cumulative contribution of the eigenvalues ​​reached 77%, 6 main factors were obtained, which were:

[0051] F1: Al2O3-Fe2O3-K2O-CaO(-)-Na2O-Ti-Ba-V-Zr-Li-Be-Sc-Co-Ga-Rb-Y-Nb-Cs-Hf-Ta-W-

[0052] Tl-Bi-Th-U-∑LREE-∑HREE, this characteristic element combination represents the surrounding rock element combination;

[0053] F2: Zn-Cd-Pb-As-Sb-Hg-(Ba)-(Ni)-(Cu)-(W), this characteristic element combination represents the mineralization element combination related to mineralization;

[0054] F3: Mo-Ni-Cr, this characteristic element combination represents the element combination of pyritization;

[0055] F4: Sr(-)-CaO(-), this characteristic element combination represents the element combination of calcite;

[0056] F5: Ge-Ag-In-(Sn)-(U), this characteristic element combination represents the medium-temperature mineralization element combination;

[0057] F6: MgO-Mn, this characteristic element combination represents the element combination of dolomitization.

[0058] Stastistic software was used to perform R-type cluster analysis (220 samples, 45 elements), and when the distance coefficient was 0.1, the Pb-Zn-Cd-As-Sb-Hg mineralization element combination was obtained ( Figure 3 ).

[0059] (2) Abnormality identification and inspection

[0060] Through comprehensive factor analysis and cluster analysis, F2 (Zn-Cd-Pb-As-Sb-Hg-(Ba)-(Ni)-(Cu)-(W)) was selected as the characteristic element combination indicating mineralization;

[0061] According to the results of geochemical analysis of the samples, the Pb and Zn element contents and the F2, F3, and F5 factor score contour lines were drawn on the middle section II plane map; the lower limit of Pb was 100ppm, and 8 levels were divided into 100, 200, 500, 1000, 2000, 5000, 10000, and 20000 in ppm; the lower limit of Zn was 500ppm, and 5 levels were divided into 500, 1000, 2000, 5000, and 10000 in ppm; 8 geochemical anomalies were obtained: in the 073# vein, on the main vein between the 064-054 exploration line 073NE, on the main vein between the 048-044 exploration line ( Figure 4 ), 36# intersects the vein in the second vein, 56# intersects the vein in the first vein, 88# intersects the vein mouth on the third vein near the main vein, and the exploration line 88NE goes to the third vein ( Figure 5 ).

[0062] 4. Construction of mathematical model of characteristic element combination anomaly and determination of existence of deep concealed ore bodies

[0063] Based on the profile measurement of the middle section of II veins (4#, 15#, 17#, 56#), the ore bodies / mineralized bodies and tectonic altered rock samples in the ore-bearing fault zone were systematically collected to conduct quantitative analysis of the Pb and Zn content (Table 1, testing unit: Northwest Nonferrous Geological Research Institute Testing Center; analysis method: chemical method was used to analyze strong mineralization and ore samples, the unit is %; other samples were analyzed by ICP-MS method, the unit is 10 -6 ), a mathematical model based on spatial position and Pb and Zn element contents was constructed, and the spatial variation law of profile elements was revealed based on this model;

[0064] Table 1 Pb and Zn content of different vein samples (10 -6 )

[0065]

[0066] In the detailed dissection of the four profiles, the 4# vein in the middle section of II is the ore-bearing profile, and the 15#, 17#, and 56# veins only show hydrothermal carbonatization, pyritization and other surrounding rock alteration (Table 1). The NE-trending compressional-torsional interlayer fault zone controls the spatial distribution of ore bodies / mineralized bodies and hydrothermal alteration, and the ore bodies are lens-shaped and occur in moderately inclined interlayer fault zones. According to the fitting curve, the first-order differential equation of the distance is obtained respectively. Through calculation, in the exploration area A of the middle section of II, the average value of the anomaly of F3 (Pb, Zn, Cu, Cd) is -0.2, and the standard deviation is 0.1, so its lowest anomaly lower limit is 0.00, and there is an isoline of F(x)>0.2. According to the mathematical model of the combined distribution of characteristic elements, F(x) is a high anomaly value, indicating that there may be blind ore bodies in the deep; in the exploration area B of the middle section of II, the average value of the anomaly of F3 (Pb, Zn, Cd) is -0.2, and the standard deviation is 0.1, so its lowest anomaly lower limit is 0.00. The value greater than twice the anomaly lower limit, that is, 0.20, is regarded as a high anomaly value ( Figure 4 ), according to the mathematical model of characteristic element combination distribution, F(x) is a high abnormal value, indicating that there may be blind ore bodies in the depth.

[0067] 5. Construction of prospecting prediction model and delineation of deep hidden ore bodies

[0068] (1) Prospecting model and location of concealed ore bodies

[0069] Analyze and summarize the abnormal characteristics of element combinations at different elevations in the deep part of the ore deposit or in the exploration area, and establish a comprehensive abnormal prospecting model ( Figure 6 ), based on which the deep ore deposit types and mineral species are inferred, and the deep key prospecting target areas are delineated ( Figure 7 , Figure 8). Combined with the development characteristics of the ore-controlling structures and the geological characteristics of the ore deposits, the distribution law of the ore-controlling structures and the structural ore-controlling types that control the abnormal element combination are studied, the mineralization center and the deep mineralization enrichment area are determined, and the deep hidden ore body occurrence area is delineated.

[0070] Combining geological conditions with structural geochemistry, structural-alteration lithofacies and gravity detection results, four target areas were selected in the deep tunnels of the mining area ( Figures 7-8 ):

[0071] Target area 1: Located in the deep part of line 064~066 on the SW side of the main vein of 064# exploration line in the exploration area of ​​middle section II A, it lies sideways to the SE direction and strikes SW-NE.

[0072] Target area 2: Located in the deep part of line 036-040 on the SW side of the main vein of exploration line 036 in exploration area A of middle section II, it lies sideways to the SE direction and strikes SW-NE.

[0073] Target Area 3: Located in the deep part of Line 36 on the east side of the F5 fault along the vein 2 in the exploration area of ​​the middle section of II B, there are a large number of NE-trending faults developed nearby, and lead-zinc mineralization is seen, which is presumed to be caused by concealed ore bodies.

[0074] Target area 4: Located in the middle section of II B exploration area, near the main vein along the third vein, deep between lines 87 and 92.

[0075] (2) Exploration Engineering Verification and Feedback

[0076] On this basis, high-precision tunnel gravity measurement was carried out in the middle section of II, and obvious gravity anomalies were obtained at the known No. 1 ore body, with a maximum anomaly of about 5g.u. According to the high-density inclined ore body gravity anomaly section model, it was inferred that the known No. 1 ore body has a large extension or there are hidden ore bodies in the depths. Tunnel EH4 measurement was carried out in the middle section of 1584m, and an obvious EH4 low resistivity anomaly of 600m×900m was obtained. Through joint efforts with enterprises, the tunnel gravity anomaly and the tunnel EH4 low resistivity anomaly were integrated, and the deep key target areas were delineated closely in combination with the mineralization geological conditions. Drilling verification found that the No. I-5 germanium-rich lead-zinc ore body ( Fig. 9 ).

[0077] Example 2: Delineation of the location of the deep concealed ore body in the peripheral exploration area of ​​a lead-zinc mine in eastern Yunnan

[0078] Although a lot of geological work has been carried out in the peripheral exploration area of ​​a lead-zinc mine, the deep prospecting work has not made much progress. Only some small vein-like ore bodies were discovered in the early stage. The coarse-grained dolomite in the Carboniferous in the exploration area has developed hydrothermal alteration such as dolomitization, pyritization, calciteization, and silicification, and the characteristics of being controlled by left-lateral compressional-torsion structures are obvious. In particular, the deep ore bodies have large changes in dip angles on the profile, and the reverse dip phenomenon is prominent. Although geophysical methods such as TEM and IP have been used, the resistivity and high polarizability anomalies obtained by these methods have strong multi-solution inferences and interpretations, and water-bearing faults, coal-bearing strata, surface high-voltage lines, and underground rail facilities in mines can all cause anomalies similar to ore bodies. It is difficult to distinguish the distribution characteristics of mineral-induced anomalies that indicate the occurrence of deep ore bodies or non-ore anomalies; it is difficult to determine the occurrence of deep concealed ore bodies in the interpretation of geochemical anomalies.

[0079] The deposit is a hydrothermal lead-zinc deposit that is clearly controlled by structure, laying the foundation for the delineation of the location of deep concealed ore bodies.

[0080] The specific implementation process of the method of the present invention is as follows:

[0081] 1. Analysis of mineralization structure

[0082] Applying the theories and methods of mining field geomechanics, we conducted special surveys of ore-controlling structures on the surface and in the deep middle tunnels of the exploration area, analyzed the geometry, kinematics, mechanics, tectonic periods and tectonic rocks of fault structures of different scales, and determined that the northeast-trending MP left-lateral compression-torsion fault, the north-south-trending LZH left-lateral torsional fault, the northeast-trending MMS compound inverted anticline, the north-northwest left-lateral torsional-tension fault, the northeast-trending tangential left-lateral compression-torsion fault, and the northeast-trending interlayer left-lateral compression-torsion fault zone are the metallogenic structures of the ore deposit, and constructed a structural ore-controlling model such as Fig.10 As shown;

[0083] 2. Structural geochemical mapping

[0084] (1) Determine the ore-bearing structures and mineralized alteration points in different veins, collect mineralized altered rock samples at a point spacing of 5 to 10 meters based on the exposure of ore-bearing fault zones and mineralized altered rocks, and increase sampling at locations with intense mineralization and alteration. The sampling length is 0.5 to 2 meters, and each sample weighs about 200 grams;

[0085] (2) Under pollution-free conditions, the collected samples are processed and reduced to 200 mesh, and divided into positive samples and duplicate samples. The positive samples are sent to a testing center with national Class A testing qualification certification for analysis. The content of trace and rare earth elements is tested by ICP-MS (inductively coupled plasma mass spectrometry); the main components of oxides are measured by rock chemical full analysis, and samples with excessively high contents of some mineralizing elements (such as Pb, Zn, etc.) are re-tested by the volumetric method. For the analysis of special elements (such as As, Sb, Hg), atomic fluorescence testing is used. Various analytical methods meet the reporting rate and detection limit requirements of each element analysis, and internal and external inspections are carried out according to specification requirements. The internal and external inspection samples are extracted with 3% code samples, and the accuracy of the test data is tested. The average error is less than 5%, and the analytical methods and instruments meet the accuracy requirements.

[0086] 3. Capture of deep weak mineralization information and its anomaly delineation

[0087] (1) Effective extraction of deep mineralization information and interpretation of anomalies

[0088] A 1:500 tunnel structural geochemical study was conducted on the middle section of II, and five main factors were obtained, F1: Ti, Ba, V, P, Zr, Li, Be, Sc, Co, Ga, Rb, Y, Nb, Cs, LREE, HREE, Hf, Ta, W, Bi, Th, Sn, Tl, Mn; F2: Pb, Zn, Ag, Cu, Cd, In, Tl, As, Sb, Hg; F3: Bi, Th, U; F4: Cr, Co, Ni, Mo; F5: -Sr. Among them, F2 represents the lead-zinc mineralization element combination, and its anomaly is consistent with the distribution area of ​​the ore body No. Ⅰ-6, indicating that the structural geochemical anomaly is a reflection of the primary halo of the ore body. F3 represents the abnormal combination of high-temperature hydrothermal elements, and the abnormal trend is NE-SW, parallel to the ore body No. Ⅰ-6, which is an abnormal reflection of the deep ore body; the characteristic element combination of F4 has strong iron affinity and sulfur affinity, representing the element combination of pyritization.

[0089] According to the characteristics of mineralization, 39 elements of the fractured structural rock samples in the distribution area of ​​the No. 1 ore body in the middle section of II were selected for R-type cluster analysis. The results are as follows: Fig.11 ):

[0090] When the distance coefficient d = 0.2, three groups of element combinations can be obtained, namely:

[0091] 1) Ti, Nb, Hf, Zr, ∑LREE, ∑HREE, Cs, Rb, Y, Li, Ga, Ta, W, Sc, Be, Co, and V are trace element combinations of altered carbonate rocks;

[0092] 2) Zn, Pb, Cd, Ag, As, and Sb are the lead-zinc mineralization element combination;

[0093] 3) Bi, Th, and U may reflect the combination of deep medium- and high-temperature mineralization elements.

[0094] (2) Abnormality identification and inspection

[0095] Comprehensive factor analysis and cluster analysis screened out F2 (Pb, Zn, Ag, Cu, Cd, In, Tl, As, Sb, Hg) as the characteristic element combination indicating mineralization. The isovalue lines of Pb and Zn element contents and F2 characteristic element combination scores were drawn on the middle section II plane map ( Fig.12 ). The abnormal F2 characteristic element combination score reflects the abnormal lead-zinc mineralization. The element combination anomaly is mainly distributed in three areas: Area I is located in the distribution area of ​​ore bodies I-6 and its periphery, which is consistent with the actual situation, which just shows that the high-value area of ​​mineralization characteristic element combination is the reflection of the primary halo of the ore body; Area II is located on the line connecting the middle of the 110 vein and the middle of the 114 vein. The abnormal area strikes NE-SW, which is consistent with the interlayer fault, which also shows that the ore body is obviously controlled by this structure; Area III is located at the southeast end of the 114 vein. The anomaly here may be related to the obvious turning of the stratum near this area, which is a favorable prospecting space; Area II is also a favorable prospecting space.

[0096] 4. Construction of mathematical model of characteristic element combination anomaly and determination of existence of deep concealed ore bodies

[0097] Based on the precise profile measurement of the 94#, 98#, 102#, 110#, and 114# veins in the middle section of II, the quantitative analysis of Pb and Zn elements was carried out through the systematic collection of ore bodies / mineralized bodies and altered structural rock samples. Similarly, a mathematical model based on spatial position and Pb and Zn element contents as variables was constructed to reveal the profile variation law of the main elements;

[0098] The 98# and 102# veins in the middle section of II are ore-bearing projects. Only hydrothermal carbonate rockization, pyritization and other surrounding rock alteration were found in other veins, but no lead-zinc mineralization was found. The ore body is lens-shaped and irregular vein-shaped and is produced in the NE-trending steeply inclined interlayer fault zone. The ore contains Pb: 7%~33.41%, Zn: 7.2%~24.0%. Based on this, the curve is fitted and the first differential of the distance is calculated respectively;

[0099] The mathematical fitting results of different veins reveal the profile distribution characteristics of ore-forming elements (Pb, Zn). Combined with the geological information of detailed dissection, the main enrichment site of ore-forming elements is in the interlayer fault zone.

[0100] According to the mathematical model of characteristic element combination distribution, F(x)=2.8 is a high abnormal value, indicating that there may be blind ore bodies in the deep.

[0101] 5. Construction of prospecting model and delineation of deep hidden ore bodies

[0102] Analyze and summarize the abnormal characteristics of element combinations at different elevations in the deep part of the ore deposit or in the exploration area, establish a prospecting model, infer the type and species of deep ore deposits, and delineate the deep key prospecting target areas. Combined with the development characteristics of the ore-controlling structure of the ore deposit and the geological characteristics of the ore deposit, study the distribution law of the ore-controlling structure and the structural ore-controlling type that control the abnormal element combination, determine the mineralization center and deep mineralization enrichment area, and delineate the location of the deep hidden ore body.

[0103] At present, some target areas have been verified, which provides a basis for mining enterprises to make decisions on increasing reserves and production and deep exploration. This example shows that this method is feasible.

Claims

1. A method for determining the existence of a hidden ore body in a deep hydrothermal deposit or an exploration area and quickly identifying its occurrence location, characterized in that: Here are the steps: (1) Apply the theory and methods of mine field geomechanics to conduct detailed measurement and analysis of the ore-forming structures in different middle sections, different veins or profiles in deep tunnels of hydrothermal deposits, identify the types of ore-forming structures in the mining area, reveal the laws of structural control of ore, and establish a structural control model; (2) Collect tectonic altered rocks in deep tunnels, boreholes or exploration work sections of the ore deposit, process and reduce the collected samples, and test the content of major ore-forming elements and trace elements related to mineralization in the samples; (3) Based on the element content of the measured profile samples, factor analysis and cluster analysis methods are used to obtain the characteristic element combination indicating deep mineralization information, draw the characteristic element combination anomaly map of the working area, and extract the spatial information of mineralization anomalies; (4) Constructing a mathematical model for characteristic element combination anomalies and determining the existence of deep concealed ore bodies Construct a geological model based on different profile sampling geological point positions x as independent variables and characteristic element combination anomalies C j The mathematical model of the function is: C j = F ( x )=A1×exp(-((x-B1 x ) / D1) 2 ) Where: F ( x ) is the abnormal combination of characteristic elements, non-dimensional unit; x is the distance, m; A1, B1, D1 are constants; j It is a combination of characteristic elements; At the same time, the first derivative function reflecting the tendency of deep concealed ore bodies is obtained: ； The mathematical model of the distribution of characteristic element combinations indicates the existence of deep concealed ore bodies: ① When F ( x ) is higher than 2 times the lowest abnormal lower limit, it is a high abnormal value, indicating that there may be a hidden ore body in the deep; F ( x ) is much lower than 2 times the lowest abnormal lower limit, it is a low abnormal value, indicating that there is no hidden ore body in the deep or the hidden ore body is located very deep; (5) Construction of prospecting model and delineation of deep hidden ore bodies Summarize the abnormal characteristics of element combinations at different elevations in the deep part of the ore deposit or in the exploration area, establish the plane and profile prospecting models of structural characteristic element combination anomalies, draw characteristic element combination anomalies-geological maps, and infer the deep ore deposit type and ore species based on them. In the deep part of the ore deposit or in the exploration area, delineate the deep key prospecting target area, combine the development characteristics of the ore-controlling structure of the ore deposit and the geological characteristics of the ore deposit, study the distribution law of the ore-controlling structure and the structural ore-controlling type that control the abnormal element combination, determine the mineralization center and deep mineralization enrichment site, and delineate the deep hidden ore body occurrence site; According to the location of deep hidden ore bodies, the preferred areas for exploration engineering verification are proposed, and engineering verification plans, target area verification implementation and information feedback are formulated to test the reliability of the delineation of the location of hidden ore bodies and realize deep mineral prospecting.

2. According to the method for quickly determining the existence and location of hidden ore bodies in deep hydrothermal deposits or exploration areas as described in claim 1, the hidden ore deposits or ore bodies with a scale of 1:200 to 1:10000 can be located and detected.

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