Rare metal mineralization potential comprehensive evaluation method based on rock geochemistry

Abstract

The invention discloses a rare metal mineralization potential comprehensive evaluation method based on rock geochemistry, and aims to solve the problems of single evaluation index and disjunction between field observation and indoor analysis in the prior art. The method comprises the following steps: obtaining geological data of an analysis area, and screening a target area based on a favorable structure background and an exposed feature criterion; identifying mineralogical and lithofacies markers and collecting sampling data; the method comprises the following steps: acquiring rock geochemical data of a sample sampled by a previous person, including multi-dimensional data including major elements, trace elements, isotope composition and the like, and calculating a quantitative evaluation index according to the data; and finally, establishing a comprehensive evaluation model by adopting a weighted scoring method to realize mineralization potential grade division and target region accurate delineation in a three-dimensional space. According to the method, organic combination of macroscopic geologic features and microcosmic geochemical data is realized, and a complete technical system from field observation to indoor analysis to engineering decision is formed.

Description

Technical Field

[0001] This invention belongs to the field of mineral exploration and metallogenic prediction technology, specifically involving a comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry. Background Technology

[0002] Highly differentiated granites, as important products of continental crustal evolution, are major carriers of rare metal minerals such as lithium, beryllium, niobium, tantalum, tungsten, and tin. These rocks typically exhibit high silica (SiO2 > 75%), high alkali content (K2O + Na2O > 8%), and low calcium, magnesium, and iron content, and show strong trace element differentiation, such as extremely low Nb / Ta ratios (<10), Zr / Hf ratios (<35), and significant rare earth element tetrad effects (TE). 1,3 >1.05). However, among the numerous highly differentiated granites, only a very small number can form economically valuable rare metal deposits. Therefore, how to accurately and efficiently evaluate their mineralization potential has become a key scientific problem and technological bottleneck that urgently needs to be solved in the field of mineral exploration.

[0003] However, existing evaluation methods have the following limitations: First, they rely heavily on isolated geochemical indicators (such as the Nb / Ta ratio), lacking organic integration with macroscopic geological features, leading to highly ambiguous evaluation results. Second, the workflow is disconnected between field geological observation and laboratory analysis and testing, making it difficult to form an effective guidance and feedback loop, failing to directly indicate the specific location of mineralization, and resulting in high exploration risks. Therefore, there is an urgent need in this field for a standardized evaluation method that can systematically integrate macroscopic prospecting indicators with microscopic analytical data and directly guide engineering verification. Summary of the Invention

[0004] The purpose of this invention is to provide a comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry, so as to overcome the shortcomings of existing technologies, such as single evaluation indicators and the disconnect between field observation and laboratory analysis.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry, comprising the following steps: S1. Obtain and analyze the geological data of the target area. Based on the preset favorable tectonic background criteria and favorable exposure characteristic criteria, select highly differentiated granite bodies from the geological data of the target area as the target area. S2. Identify mineralogical and petrographic markers related to rare metal enrichment in the target area, and obtain previous rock sampling samples based on the identified markers; S3. Obtain rock geochemical data of previous samples, including major elements, trace elements and isotopic composition, and calculate quantitative mineralization potential evaluation indicators based on the rock geochemical data. S4. Based on quantitative mineralization potential evaluation indicators, a comprehensive evaluation model is established using a weighted scoring method to classify the mineralization potential of the target area and delineate the drilling verification target area in three-dimensional space.

[0006] Favorable tectonic settings include: extensional tectonic environments located after the amalgamation of major orogenic belts, and undeformed equiaxed small rock masses; Favorable exposure features include: a positive topography with well-preserved fine-grained marginal facies, and / or the development of alteration halos, and / or the presence of pegmatite veins.

[0007] In S2, mineralogical and petrographic markers associated with rare metal enrichment in the target area are identified, including: Identify at least one mineral among topaz, fluorite, amazonite, and lepidolite, and mark it as a mineralogical indicator; Obtain geological mapping data of the target area, and delineate the terminal facies zone from biotite granite to muscovite granite or topaz granite based on the mapping data, marking it as a petrographic marker.

[0008] In S3, rock geochemical data from previous samples were obtained, including: Whole-rock major and trace element data; Micro-area compositional data of accessory minerals, including zircon and / or apatite; Isotopic data, including zircon Hf-O isotopes or whole-rock Sr-Nd isotopes.

[0009] In S3, quantitative mineralization potential evaluation indicators include: differentiation degree index, TE 1,3 Differentiation coefficient, oxygen fugacity index.

[0010] Differentiation indicators include the Nb / Ta ratio, Zr / Hf ratio, and K / Rb ratio.

[0011] TE 1,3 The formula for calculating the differentiation coefficient is: TE 1,3 =[(Ce n ×Nd n ) / (La n ×Sm n )+(Tb n ×Lu n ) / (Gd n ×Yb n )] Among them, TE 1,3A value >1.05 indicates the presence of a rare earth tetrad effect, reflecting the interaction between the molten fluid and the rare earth elements.

[0012] Oxygen fugacity indices include: corrected values ​​based on the whole-rock Fe2O3 / FeO ratio, zircon Ce / Ce* ratio, or amphibole. FMQ value.

[0013] In S4, a weighted scoring method is used to establish a comprehensive evaluation model, including: Set favorable thresholds for mineralization for quantitative indicator data; The data for each indicator are compared with the corresponding thresholds and weighted accordingly to calculate the comprehensive score. Based on the comprehensive score, the mineralization potential is divided into three levels: high, medium, and low.

[0014] In S4, the drilling verification target area is delineated in three-dimensional space, including: Geological mapping data of the target area was obtained, and rock geochemical data were integrated. The area with the most extreme quantitative mineralization potential evaluation indicators and the strongest alteration and mineralization was delineated as the first-level drilling verification target area.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: 1. This invention provides a comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry. By constructing a complete technical chain from macroscopic screening to microscopic verification, it achieves deep integration of multi-source information and overcomes the limitations of traditional methods that rely on a single indicator.

[0016] 2. By closely linking field marker identification with systematic indoor sampling and precise analysis, an effective "observation-analysis-decision" closed loop and technical system have been established, solving the problem of disconnect between field and indoor work and significantly improving the targeting and efficiency of exploration work.

[0017] 3. By introducing multi-parameter quantitative indicators and weighted scoring models, qualitative geological understanding is transformed into objective quantitative evaluation results, and the drilling target area is accurately delineated in three-dimensional space, providing a scientific and intuitive basis for engineering deployment and greatly reducing exploration risks.

[0018] 4. This method has a complete system, clear standards, and strong operability. It has important application value for guiding the exploration practice of various rare metal minerals related to highly differentiated granites and promoting breakthroughs in mineral exploration. Attached Figure Description

[0019] Figure 1 This is a flowchart of a comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry, as described in an embodiment of the present invention.

[0020] Figure 2This is a flowchart of a comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry in another embodiment of the present invention.

[0021] Figure 3 This is a differentiation diagram in an embodiment of the present invention.

[0022] Figure 4 TE in the embodiments of the present invention 1,3 Differentiation coefficient diagram. Detailed Implementation

[0023] Highly differentiated granites are important carriers of rare metal mineral deposits, but their mineralization potential assessment faces significant technical bottlenecks. Existing methods have two main limitations: firstly, they rely excessively on isolated geochemical indicators, lacking organic integration with macroscopic geological features, leading to highly ambiguous evaluation results; secondly, there is a severe disconnect between field geological observation and laboratory data analysis, making it difficult to form an effective guidance-feedback cycle and accurately locate mineralization sites, resulting in persistently high exploration risks. Therefore, there is an urgent need to establish a standardized evaluation method that can systematically integrate macroscopic prospecting indicators with microscopic analytical data and directly guide engineering verification.

[0024] Based on the above background, this invention proposes a comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry. It ensures the accuracy of the research object by screening target areas based on preset criteria; establishes a direct link between field observation and laboratory analysis by identifying mineralogical and petrographic markers to guide systematic sampling; overcomes the limitations of single-parameter discrimination by calculating quantitative indicators using multi-dimensional rock geochemical test data; and finally achieves grade classification and target area delineation through weighted scoring, forming a complete technical closed loop from field identification to exploration decision-making.

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that the described embodiments are merely some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0026] Reference Figure 1 The image shows a specific implementation of the comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry provided by the present invention, comprising: S1. Obtain and analyze the geological data of the target area. Based on the preset favorable tectonic background criteria and favorable exposure characteristic criteria, select highly differentiated granite bodies from the geological data of the target area as the target area. S2. Identify mineralogical and petrographic markers related to rare metal enrichment in the target area, and obtain previous rock sampling samples based on the identified markers; S3. Obtain rock geochemical data of previous samples, including major elements, trace elements and isotopic composition, and calculate quantitative mineralization potential evaluation indicators based on the rock geochemical data. S4. Based on quantitative mineralization potential evaluation indicators, a comprehensive evaluation model is established using a weighted scoring method to classify the mineralization potential of the target area and delineate the drilling verification target area in three-dimensional space.

[0027] In this specific implementation, S1 acquires and analyzes regional geological data, and selects targets based on preset criteria for favorable tectonic background and favorable outcrop characteristics. This establishes a scientific basis for exploration targets at the regional scale, providing accurate research objects for subsequent work. S2 identifies mineralogical and petrographic markers directly related to rare metal enrichment within the identified target area, and obtains previous rock sampling samples based on these markers. This step establishes a direct link between geological feature identification and sample acquisition, ensuring the geological representativeness of the research samples.

[0028] S3 acquires rock geochemical data from previous samples, including major element, trace element, and isotopic composition, and calculates quantitative mineralization potential evaluation indicators based on this data. This process constructs a parameter system that comprehensively reflects the rock geochemical characteristics. S4, based on the aforementioned quantitative indicators, establishes a comprehensive evaluation model using a weighted scoring method to classify the mineralization potential of the target area and accurately delineate the drilling verification target area in three-dimensional space, transforming multi-source geological and geochemical information into specific exploration decision-making basis.

[0029] The above four steps form a complete technical chain: target area screening in S1 provides the spatial scope for marker identification and sample acquisition in S2; the samples acquired in S2 provide the material basis for geochemical analysis in S3; and the quantitative indicators generated in S3 provide data support for the comprehensive evaluation in S4. The entire implementation process achieves a technical closed loop from regional screening to target area location, and from geological identification to quantitative evaluation, ensuring the reliability and practicality of the evaluation results.

[0030] In another specific embodiment of the present invention, the provided comprehensive evaluation method for rare metal mineralization potential based on rock regional chemistry is referenced. Figure 2 As shown in the figure, this embodiment elaborates on the four-stage workflow of a comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry, as follows: 1. Construct background screening to quickly screen at the regional scale and lock in the target area.

[0031] This stage involves tectonic background analysis, including collecting and applying geological maps, scientific research results, and remote sensing imagery of the target area. Priority is given to screening undeformed equiaxed small rock masses located in extensional tectonic environments after the main orogenic belts have been assembled, and these are marked as favorable tectonic settings.

[0032] Next, an assessment of the degree of erosion was conducted. Through remote sensing interpretation and analysis of previous data, low-erosion rock masses with positive topography, well-preserved fine-grained marginal facies, strong alteration halos (albitalization, greisenization), or associated pegmatite veins were selected and marked as favorable exposure features. In the covered area, concealed rock masses were inferred by combining geophysical anomalies such as low gravity and low magnetic anomalies.

[0033] Finally, the results show that 1-3 target rock masses with the greatest mineralization potential have been preliminarily identified, and the project will proceed to the next stage.

[0034] 2. In the data collection and verification stage, the analysis and "diagnosis" of the identified targets are carried out to identify exposure characteristics and lithofacies zoning.

[0035] First, mineralogical identification was performed to identify mineralogical markers related to rare metal enrichment in the target area. On hand specimens and outcrops, characteristic minerals such as topaz, fluorite, amazonite, and lepidolite were accurately identified to confirm that it is a light-colored granite with high alkali and rich fluorine.

[0036] Next comes petrographic zoning analysis, identifying petrographic markers related to rare metal enrichment in the target area. This includes geological mapping of the target area and, based on the mapping results, delineating the terminal facies zones evolving from biotite granite to muscovite granite or topaz granite. Specifically, this involves large-scale (e.g., 1:2000) geological mapping of the area (preferably large-scale) to finely characterize the internal structure of the rock mass and determine whether an evolutionary sequence of biotite granite, two-mica granite, muscovite granite, or amazonite / topaz granite exists. The core task is to delineate the spatial distribution of the evolutionary "terminal" facies zones (at least muscovite granite and beyond).

[0037] Existing data should be collected selectively, traversing different lithofacies zones, with a focus on collecting fresh sample data of terminal evolutionary facies (such as topaz granite and strongly greisenized zones) and associated pegmatites. For each sample, detailed records should be kept of the location, lithology, mineral assemblage, and alteration characteristics.

[0038] 3. In the data analysis and verification stage, accurate quantitative verification of the judgments made in the first two stages is the key to technology integration.

[0039] 3.1 First, sample data collection should be conducted. Based on the selected exploration area, systematically collect fresh, unaltered, highly differentiated granite sample data from previous studies. For each rock body, 5-10 representative samples should be collected, covering different facies zones (marginal, transitional, and central facies), avoiding rocks with strong weathering or hydrothermal alteration. The collected sample data from previous studies should include the following processing steps: Crushing and grinding: The rock sample is crushed to below 200 mesh to prepare a whole-rock powder sample; Single mineral separation: Separating single minerals such as zircon, apatite, and amphibole through methods such as heavy liquid separation and magnetic separation; Target preparation and polishing: A single mineral is made into an epoxy resin target, which is then polished and subjected to cathodoluminescence (CL) or backscattered electron (BSE) imaging for micro-area analysis. It should be noted that the sample data should cover different facies zones of the rock mass to ensure representativeness; single mineral selection should ensure that the grains are intact and free of cracks to avoid the accuracy of the composition data being affected by later modifications.

[0040] 3.2 After collecting and organizing the sample data, corresponding analytical test data were collected, mainly rock geochemical data. The analytical tests involved in the data collected in this invention mainly include three categories: whole-rock major and trace element analysis data; micro-area composition analysis data of accessory minerals, including zircon and / or apatite; and isotopic analysis data, including zircon Hf-O isotope analysis or whole-rock Sr-Nd isotope analysis.

[0041] The collected whole-rock major and trace element analysis data should be performed using X-ray fluorescence spectrometry (XRF) and inductively coupled plasma mass spectrometry (ICP-MS); XRF is used for major element analysis, with detection limits typically below 0.01%; ICP-MS is used for trace elements, with detection limits reaching the ppb level.

[0042] During the analysis, national first-class standard materials (such as GSR-1 and GSR-3) must be added for quality monitoring to ensure data accuracy. Single-mineral micro-area analysis uses electron probe microanalysis (EMPA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Zircon U-Pb dating and trace element analysis are performed simultaneously, with the laser beam diameter typically 20-40 μm and the frequency 5-10 Hz. Before analysis, cathodoluminescence imaging is used to avoid defect areas such as cracks and inclusions.

[0043] Isotope analysis includes zircon Hf-O isotope analysis and whole-rock Sr-Nd isotope analysis. Zircon O isotope analysis was performed using secondary ion mass spectrometry (SIMS), and Hf isotope analysis was performed using (LA-MC-ICP-MS). Isotope data must be calibrated with standard materials (such as zircon standard 91500 for O isotope calibration) to ensure analytical accuracy.

[0044] 3.3 Data processing and graphical analysis are performed to form quantitative mineralization potential evaluation indicators, specifically including differentiation degree indicators, TE 1,3 Differentiation coefficient, oxygen fugacity index.

[0045] (1) The degree of differentiation is evaluated using the following indicators: Elemental ratios of Nb / Ta < 7, Zr / Hf < 25, and K / Rb < 150 indicate that the magma underwent highly differentiated crystallization. (2) TE 1,3 The differentiation coefficient is evaluated using the following indicators: TE 1,3 =[(Ce n ×Nd n ) / (La n ×Sm n )+(Tb n ×Lu n ) / (Gd n ×Yb n The rare earth element ratio (Rb / Sr) > 1.05 indicates a four-part rare earth grouping effect, reflecting the interaction between the molten metal and the mineral. Trace element ratios (Rb / Sr > 5, Ba < 100 μg / g) indicate enrichment in strongly incompatible elements and depletion in compatible elements. When all the above indicators simultaneously meet the favorable threshold for mineralization, the rock mass is considered to have a high degree of differentiation, which is conducive to the enrichment of rare metals. (3) Magmatic oxygen fugacity controls the behavior of variable valence elements (such as W, Sn, Mo, and Cu), directly affecting mineralization types. Therefore, in this specific implementation, the oxygen fugacity index is evaluated using multiple methods: Whole-rock index: Based on the relationship between Fe2O3 / FeO ratio and SiO2 content, the index is corrected. When Fe2O3 / FeO > 0.8 after correction, it indicates a relatively reducing environment, which is conducive to the enrichment of tungsten and tin. Zircon oxygen fugacity meter: calculated based on the zircon Ce / Ce* ratio and Ti temperature, Ce / Ce*=Ce n / (La n ×Pr n ) 0.5 A high Ce / Ce* value (typically >100) indicates a high oxygen fugacity environment, which is conducive to copper-molybdenum mineralization. Amphibole oxygen fugacity meter: Calculates oxygen fugacity using the major components of amphibole. FMQ value, FMQ>+1 indicates a high oxygen fugacity environment.

[0046] 4. In the comprehensive assessment and target area location stage, based on the above indicators, a weighted scoring system is established to classify the rare metal mineralization potential of highly differentiated granites into three levels: High-potential rock mass (score ≥ 85 points): simultaneously meets the following criteria: high differentiation (Nb / Ta < 5, Zr / Hf < 20, TE < 5). 1,3 >1.10), with suitable oxygen fugacity (adjusted according to the target mineral type) and a source area rich in ore-forming elements. This type of rock mass is a priority exploration target, and it is recommended to verify it in conjunction with large-scale geological mapping, geochemical scanning, and engineering.

[0047] Medium-potential rock mass (score 60-84): Some indicators meet the mineralization threshold, but certain defects exist (such as moderate differentiation). Further work is recommended, such as supplementary sampling analysis and deep geophysical exploration, to clarify its mineralization potential.

[0048] Low-potential rock masses (score <60 points): Most indicators do not meet the mineralization threshold, so exploration can be temporarily suspended to avoid wasting resources.

[0049] Target area delineation: Integrate geological mapping results and geochemical anomalies (such as extremely low Nb / Ta areas) to accurately delineate the "end" facies zone with the most extreme geochemical indicators and the strongest alteration and mineralization in space as the first-level drilling verification target area.

[0050] Output a mineralization potential assessment report: The assessment report should clearly provide a target area location map to support engineering verification.

[0051] This specific embodiment provides a comprehensive evaluation method for rare metal mineralization potential based on regional rock chemistry. Through dynamic threshold discrimination, it establishes adjustable threshold ranges for different geological backgrounds and mineral types, rather than fixed standards. For example, for tungsten-tin mineralization, it emphasizes low oxygen fugacity conditions; for copper-molybdenum mineralization, it focuses on high oxygen fugacity environments, making the evaluation results more targeted.

[0052] The following example, using the evaluation method of this invention in the Zhangbaoshan Baishitouquan (BST) super-large rubidium deposit in the eastern Tianshan Mountains of Xinjiang, further illustrates the technical solution of this invention: 1. Structural geological screening and selection background: The eastern Tianshan orogenic belt in Xinjiang was selected as the target area. The Zhangbaoshan Baishitouquan (BST) super-large rubidium deposit has been discovered in this area, with a basic Rb2O reserve of 67,000 tons and a prospective resource of over 900,000 tons. It is an ideal object to verify the effectiveness of the method of this invention.

[0053] 1.1. Tectonic Background Analysis: Regional geological studies indicate that the BST pluton was intruded into the Early Triassic (~250 Ma) and formed in an intracontinental extensional setting triggered by the subduction of the Paleo-Tethys Ocean, which is consistent with the favorable tectonic criterion of "post-orogenic extensional environment" set in this invention.

[0054] 1.2. Assessment of erosion degree: Remote sensing interpretation and preliminary field exploration show that the BST rock mass is well exposed and has a complete vertical lithofacies zoning (from zone a to zone e) and a large number of amazonite pegmatite veins, indicating that the degree of erosion of the rock mass is moderate and the precious top high-separation heterogeneous zone and ore body are well preserved.

[0055] The deliverables of this phase: Based on the favorable tectonic setting and outcrop characteristics, the White Stone Spring (BST) pluton has been formally identified as a high-potential target for detailed evaluation and has entered the second phase of field verification.

[0056] 2. Data Collection 2.1. Mineralogical and Petrographic Zoning Analysis: Using large-scale geological mapping results, five key lithofacies zones of the BST pluton were accurately identified and delineated, in the following order: leucogranite (zone a), amazonite-bearing granite (zone b), amazonite-bearing granite (zone c), topaz-bearing amazonite-bearing granite (zone d), and topaz albite granite (zone e). Simultaneously, key minerals such as topaz, fluorite, amazonite, and lepidolite were systematically identified. This not only confirms the high evolutionary properties of the pluton but also clearly reveals the enrichment pattern of Rb content gradually increasing from zone a to zone e.

[0057] 2.2. Targeted Sampling: In strict accordance with the requirements of this invention, the sampling line system traversed the above 5 lithofacies zones, focusing on collecting a series of fresh rock samples in the rich ore zones c, d, and e and in amazonite pegmatite veins to ensure the representativeness of the samples.

[0058] 3. Data analysis and verification Whole-rock major and trace element analysis, and accessory mineral micro-area composition analysis were performed on the collected samples.

[0059] Key data and multi-dimensional indicator analysis: 3.1. Evaluation of the degree of differentiation, referring to Figure 3 As shown, whole-rock geochemical data indicate that the rock mass is characterized by high silica (SiO2 up to 76.39%), high alkali (Na2O+K2O up to 11.4%), and strong peraluminous properties. From zone a to zone e, the Nb / Ta ratio drops sharply from 7.9 to 2.0, and the Zr / Hf ratio drops from 10.00 to 4.57, far below the high potential threshold set in this invention, indicating that the Baishitouquan rock mass has undergone extreme magmatic differentiation.

[0060] 3.2.TE 1,3 Differentiation coefficient, refer to Figure 4 As shown: Based on the quantitative index of the rare earth element four-group effect defined in this invention, the rare earth distribution pattern of the sample was calculated. The results show that its TE 1,3The differentiation coefficient ranges from 1.08 to 1.15, significantly higher than the critical value of 1.05 for mineralization potential. This data quantitatively confirms the aforementioned evaluation of differentiation degree, indicating that the rock mass underwent strong melt-fluid interaction during the magma-hydrothermal evolution process, which is a key geochemical indicator of efficient enrichment of rare metals.

[0061] 3.3. Oxygen fugacity: Based on the comprehensive calculation of the zircon Ce / Ce* ratio and the whole-rock Fe2O3 / FeO ratio used in this invention, the oxygen fugacity range during the diagenetic and mineralization period of the rock mass is obtained to be -2.0 to +0.5, which is a relatively reducing to weakly oxidizing environment. This effectively inhibits the crystallization of iron and titanium oxides and promotes the continuous enrichment of rare elements such as rubidium in the residual melt-hydrothermal fluid, providing important physicochemical constraints for the mineralization model described in this invention.

[0062] 4. Comprehensive analysis and target area localization 4.1. Weighted Scoring and Potential Grade Determination: All the above quantitative indicators (extreme degree of differentiation, strong magma-hydrothermal transformation, favorable source area, consistency with mineralization age, and huge resource scale) were substituted into the weighted scoring system of this invention for calculation. The comprehensive score of the BST rock mass far exceeded 85 points, and it was indisputably rated as an "ultra-high potential mineralization rock mass".

[0063] 4.2. 3D Modeling and Target Area Delineation: Integrating lithofacies zoning maps, geochemical data (such as Rb and Nb / Ta content contour lines), and mineralogical information, a high-precision 3D geological model of the BST pluton was constructed. In the model, zones c, d, and e in the upper part of the pluton, especially the areas enriched in type II zircon and exhibiting the most extreme geochemical indices, were delineated as the highest priority exploration target areas. This invention clearly indicates that these areas are the core locations where rubidium ore bodies are found.

[0064] 4.3. Summary of Metallogenic Mechanism and Exploration Recommendations: The application of the method described in this invention not only evaluated the potential but also deepened the understanding of the metallogenic mechanism: Under an extensional background, the BST pluton was formed from F- and Rb-rich magma formed by the remelting of ancient crust. After highly differentiated evolution, during the magma-hydrothermal transition stage, Rb migrated in the form of fluorine complexes through the action of F-rich fluids and eventually entered the lattices of potassium feldspar (amaranth) and mica (lithium iron mica), enriching into mineralization. Based on this, the evaluation report can recommend focusing exploration on the upper facies zone of the pluton.

[0065] The above specific implementation methods demonstrate the objective existence of the Zhangbaoshan Baishitouquan super-large rubidium deposit and its detailed geological and geochemical data, providing the strongest verification for the method of this invention. Applying the four-stage workflow and five key prospecting indicators of this invention, the entire process of the deposit from "favorable tectonic setting" to "final mineralization location" was successfully traced and analyzed, and the evaluation conclusions are highly consistent with the actual situation of the deposit.

[0066] This invention provides a systematic, accurate, and practical comprehensive evaluation method for the rare metal mineralization potential of highly differentiated granites. By integrating multi-scale geochemical indicators, a hierarchical discrimination system is established, significantly improving the scientific rigor and reliability of mineralization potential evaluation. This invention has broad applicability, applicable not only to regional mineral prospect evaluation but also to the selection of specific exploration target areas. As mineral exploration work develops towards deeper and more concealed mineral deposits, the widespread application of this invention is of great significance for achieving breakthroughs in the discovery of strategic mineral resources in my country.

[0067] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. The present invention is not limited to the above embodiments and description. Any modifications, equivalent substitutions, and improvements made within the spirit and scope of the present invention should be included within the protection scope of the claims. The protection scope of the present invention should be defined by the claims and their equivalents.

Claims

1. A comprehensive evaluation method for the mineralization potential of rare metals based on rock geochemistry, characterized in that, The method includes the following steps: S1. Obtain and analyze the geological data of the target area. Based on the preset favorable tectonic background criteria and favorable exposure characteristic criteria, select highly differentiated granite bodies from the geological data of the target area as the target area. S2. Identify mineralogical and petrographic markers related to rare metal enrichment in the target area, and collect previous sampling samples based on the identified markers; S3. Obtain rock geochemical data of previous samples, including major elements, trace elements and isotopic composition, and calculate quantitative mineralization potential evaluation indicators based on the rock geochemical data. S4. Based on quantitative mineralization potential evaluation indicators, a comprehensive evaluation model is established using a weighted scoring method to classify the mineralization potential of the target area and delineate the drilling verification target area in three-dimensional space.

2. The comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry according to claim 1, characterized in that, The favorable tectonic setting includes: undeformed equiaxed small rock masses located in an extensional tectonic environment after the main orogenic belt has been assembled; The favorable exposure features include: a rock mass that is orthotopic and retains well-preserved fine-grained marginal facies, and / or has developed alteration halos, and / or is associated with pegmatite veins.

3. The comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry according to claim 1, characterized in that, In step S2, the identification of mineralogical and petrographic markers related to rare metal enrichment in the target area includes: Identify at least one mineral among topaz, fluorite, amazonite, and lepidolite, and mark it as a mineralogical indicator; Obtain geological mapping data of the target area, and delineate the terminal facies zone from biotite granite to muscovite granite or topaz granite based on the mapping data, marking it as a petrographic marker.

4. The comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry according to claim 1, characterized in that, In step S3, rock geochemical data from previous samples are obtained, including: Whole-rock major and trace element data; Micro-area compositional data of accessory minerals, including zircon and / or apatite; Isotopic data, including zircon Hf-O isotopes or whole-rock Sr-Nd isotopes.

5. The comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry according to claim 1, characterized in that, In S3, the quantitative mineralization potential evaluation indicators include: differentiation degree index, TE 1,3 Differentiation coefficient, oxygen fugacity index.

6. The comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry according to claim 5, characterized in that, The differentiation indicators include the Nb / Ta ratio, Zr / Hf ratio, and K / Rb ratio.

7. The comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry according to claim 5, characterized in that, The TE 1,3 The formula for calculating the differentiation coefficient is: yourself 1,3 =[(What n ×Nd n ) / (At n ×Sm n )+(Tb n ×Mon n ) / (Gd n ×Yb n )] Among them, TE 1,3 A value >1.05 indicates the presence of a rare earth tetrad effect, reflecting the interaction between the molten fluid and the rare earth elements.

8. The comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry according to claim 5, characterized in that, The oxygen fugacity index includes: a correction value based on the whole-rock Fe2O3 / FeO ratio, a zircon Ce / Ce* ratio, or an amphibole. FMQ value.

9. The comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry according to claim 1, characterized in that, In S4, a comprehensive evaluation model is established using a weighted scoring method, including: Set favorable thresholds for mineralization for quantitative indicator data; The data for each indicator are compared with the corresponding thresholds and weighted accordingly to calculate the comprehensive score. Based on the comprehensive score, the mineralization potential is divided into three levels: high, medium, and low.

10. The comprehensive evaluation method for rare metal mineralization potential based on rock geochemistry according to claim 1, characterized in that, In step S4, delineating the drilling verification target area in three-dimensional space includes: Geological mapping data of the target area was obtained, and rock geochemical test data were integrated. The area with the most extreme quantitative mineralization potential evaluation indicators and the strongest alteration and mineralization was delineated as the first-level drilling verification target area.

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