A method for delineating sodium feldsparization uranium ore bodies in porphyritic granite

Abstract

This invention belongs to the field of uranium exploration technology and provides a method for delineating albite-altered uranium orebodies in porphyritic granite. First-scale geological surveys are used to obtain the spatiotemporal distribution patterns and fault structures of magmatic rocks in the mining area. Based on the lithofacies classification results, the distribution range of the porphyritic granite is delineated. Within this range, second-scale surface surveys are used to screen for albite alteration anomalies. Combined with underground geophysical exploration to identify concealed alterations, and through vertical control of measured profiles and verification by microscopic rock and mineral identification, the three-dimensional spatial distribution of the albite alteration zone is delineated. Within the alteration zone, shallow mineralization characteristics are clarified through surface trenching. A first-degree exploration network of drilling is deployed to trace the vertical extension. Through cross-verification of macroscopic uranium grade testing and micromineralogical testing, the basic morphology of the uranium orebodies is determined. Within the range of the basic morphology, a second-degree exploration network of intensified drilling is deployed to iteratively correct the orebodies' boundaries. Through a progressive process of gradually narrowing the scope and increasing accuracy, high-precision delineation of the uranium orebodies is achieved.

Description

Technical Field

[0001] This invention belongs to the field of uranium exploration technology and provides a method for delineating albite uranium ore bodies in porphyritic granite. Background Technology

[0002] Uranium, as a core strategic resource for nuclear energy development and national defense, has significant engineering value and strategic importance in the research and application of efficient and precise exploration technologies. Alkali-alteration uranium deposits are an important type of granite-type uranium deposits. The albite alteration zone within porphyritic granite is the core favorable geological unit for the occurrence of this type of uranium ore body. Accurately delineating the albite uranium ore body in porphyritic granite is a crucial step in the exploration of alkali-alteration uranium deposits.

[0003] Currently, exploration of this type of uranium orebody typically employs geological mapping, gamma-ray spectroscopy area measurement, and drilling to expose the ore body, supplemented by rock and mineral identification and whole-rock geochemical testing. This involves controlling the sodium replacement of uranium orebodies at both shallow and deep depths according to standardized grid patterns. However, this approach suffers from several drawbacks: macroscopic anomalies are highly ambiguous, the location accuracy of deep orebodies is insufficient, it is difficult to distinguish non-mineralized sodium replacement, microscale mineralization identification is not targeted effectively, and there is a lack of unified exploration procedures, technical standards, and data interpretation specifications. This results in significant differences in exploration results across different mining areas and among different personnel, low standardization, and inconsistent quality of findings.

[0004] Meanwhile, the low accuracy of ore body delineation in the early stages of exploration can easily lead to blind deployment of subsequent exploration projects and a high proportion of ineffective projects, significantly increasing the time and economic costs of uranium exploration and severely restricting the efficient advancement of subsequent exploration, prospecting and resource evaluation work. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a method for delineating albite uranium ore bodies in porphyritic granite. This method can progressively narrow down the target area by following a progressive exploration logic from regional to local, from surface to subsurface, and from macroscopic to microscopic perspectives, thereby achieving high-precision delineation of uranium ore body boundaries.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A method for delineating albite uranium orebodies in porphyritic granite includes: conducting a first-scale geological survey to obtain the spatiotemporal distribution patterns and fault structures of magmatic rocks within the mining area, and then delineating the distribution range of porphyritic granite within the mining area based on the magmatic rock lithofacies classification results; within the distribution range of porphyritic granite, conducting a second-scale surface geological survey to preliminarily screen albite alteration anomaly zones, identifying the range of underground concealed albite alteration through underground geophysical surveys, and then, through vertical control of geological measured profiles and verification of authenticity by microscopic rock and mineral identification, three-dimensionally delineating the spatial distribution of the albite alteration zone; and further delineating the albite alteration zone in the porphyritic granite... Within the alteration zone, the surface boundaries and development characteristics of the shallow mineralization alteration zone are first obtained through surface trenches. Then, a deep drilling project with the first exploration grid is deployed to trace the vertical extension of the ore body. The basic morphology of the uranium ore body is determined by cross-validation results of macroscopic uranium grade testing of core samples and micromineralogical testing of mineralized rocks. Within the range of the basic morphology of the uranium ore body, a second exploration grid of intensified drilling is deployed, and the ore body boundary is iteratively corrected based on the core test results of the intensified drilling project, ultimately delineating the true development morphology of the uranium ore body. The first scale is larger than the second scale, and the first exploration grid is larger than the second exploration grid.

[0007] The above-mentioned scheme establishes a multi-level progressive exploration process from regional geological surveys to intensified drilling verification, gradually narrowing down the exploration target area. It organically connects macro-geological surveys, geophysical measurements, measured profiles, microscopic identification, drilling verification, and intensified correction, achieving high-precision delineation of the boundaries of albite uranium ore bodies in porphyritic granite. This solves the problems of strong ambiguity in macro-anomalies, insufficient accuracy in locating deep ore bodies, and difficulty in accurately distinguishing alteration ranges and mineralization enrichment zones in traditional exploration methods.

[0008] Optionally, the first-scale regional geological survey includes remote sensing image interpretation, first-scale route geological survey, and fault structure occurrence measurement and statistics. Remote sensing image interpretation is used to initially extract macroscopic distribution information of rock masses and structures; the first-scale route geological survey is used to confirm lithological types, rock mass occurrence characteristics, and geological boundaries in the field; and fault structure occurrence measurement and statistics are used to clarify the tectonic control of rock formations. These three elements jointly support subsequent magmatic lithofacies classification. The second-scale surface geological survey is a second-scale route geological survey used to comprehensively screen for surface albite alteration anomalies within the porphyritic granite area. Geophysical surveys are induced polarization (IP) gradient detection, using survey lines laid out based on the alteration anomaly areas screened by the second-scale geological survey. This is used to detect deep-seated concealed alteration and refine alteration boundaries, providing data support for the scientific layout of subsequent geological profiles. The first scale is 1:10000, and the second scale is 1:5000.

[0009] Optionally, the basic morphology of the uranium ore body can be determined by cross-validating the results of macroscopic uranium grade testing of core samples and micromineralogical testing of mineralized rocks. This includes: analyzing the mineral composition, uranium occurrence state, and albite alteration characteristics of mineralized rocks through micromineralogical testing to verify the genetic correspondence between uranium mineralization and albite alteration, and eliminating false mineralization anomalies caused by shallow weathering; combining the uranium content data from macroscopic uranium grade testing of core samples to quantitatively divide mineralized enrichment sections and non-mineralized sections, accurately define the boundary position of the ore body, and jointly determine the basic spatial morphology of the uranium ore body.

[0010] Optionally, micromineralogical testing can be performed using electron probe microanalysis to measure the mineral composition, elemental occurrence, and mineral alteration characteristics of the core.

[0011] Optionally, a preliminary screening of albite alteration anomaly zones can be conducted through a second-scale surface geological survey, combined with underground geophysical surveys to identify the extent of concealed albite alteration. This includes: using the albite alteration anomaly zones screened by the second-scale surface geological survey as probe lines and observation points, and using electrical detection principles to obtain the electrical parameter characteristics of the rock mass; distinguishing altered rock masses from fresh granite bodies based on differences in electrical parameters, and delineating the extent of deep concealed and weakly developed albite alteration.

[0012] Optionally, the three-dimensional spatial distribution of the albite alteration zone is delineated through vertical control of geologically measured profiles and verification of authenticity using microscopic rock and mineral identification. This includes: establishing a third-scale geologically measured profile (1:2000) based on the electrical parameters of the rock mass; collecting rock samples along the measured profile at different alteration intensities and spatial strata; preparing thin sections of the rock for microscopic rock and mineral identification; determining the degree of albite alteration development, mineral replacement mechanism, and formation period; eliminating false surface alteration anomalies; and finally forming the three-dimensional spatial distribution of the albite alteration zone.

[0013] Optionally, within the basic morphological range of the uranium ore body, a second exploration grid of intensified drilling is deployed, including: for key sections where the ore body boundaries are ambiguous, the mineralization thickness and grade variation gradient is greater than a preset threshold, and the mineralization continuity is uneven, a second exploration grid of intensified drilling is deployed; the first exploration grid is 80m×80m, and the second exploration grid is 40m×40m.

[0014] Optionally, the orebody boundary can be iteratively corrected based on the core test results of the in-situ drilling project, including: iteratively correcting the orebody's planar and vertical boundaries, orebody thickness, and grade distribution characteristics.

[0015] Optionally, the distribution range of porphyritic granite can be obtained based on the first-scale geological survey, including: classifying lithofacies based on the formation environment, rock structure, mineral composition and degree of crystallization of igneous rocks, and drawing an igneous lithofacies diagram; delineating the distribution range of porphyritic granite based on the specific lithological characteristics of porphyritic granite in the igneous lithofacies diagram.

[0016] The technical solution provided by this invention has the following advantages compared with the prior art: This invention constructs a progressive exploration logic through multi-scale geological surveys with progressively smaller scales and increasingly dense drilling networks. First, it delineates the ore-bearing porphyritic granite range across the entire mining area. Then, it uses a combination of surface screening, underground geophysical identification, vertical profile control, and microscopic verification to three-dimensionally delineate the albite alteration zone. Subsequently, it uses cross-validation of macroscopic and microscopic tests to determine the basic morphology of the uranium orebody. Finally, it uses iterative drilling to accurately delineate the true development morphology of the uranium orebody. This effectively solves the problems of strong ambiguity in macroscopic anomalies, insufficient accuracy in locating deep orebodies, and difficulty in accurately distinguishing alteration ranges and mineralization enrichment zones in traditional exploration methods. It forms a unified and standardized exploration process, avoiding the drawbacks of low standardization and inconsistent quality in exploration results. It also reduces the blindness of subsequent exploration engineering deployment, lowers the proportion of ineffective projects, and reduces the time and economic costs of exploration, effectively ensuring the high-precision delineation of albite uranium orebodies in porphyritic granite and the efficient advancement of subsequent exploration and evaluation work.

[0017] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart illustrating the exploration process of albite uranium ore bodies in porphyritic granite according to an embodiment of the present invention.

[0020] Figure 2 This is a geological map of the test area in an embodiment of the present invention.

[0021] Figure 3 This is a cross-sectional view of the exploration line according to an embodiment of the present invention.

[0022] Among them, 1. Quaternary Holocene; 2. Lower Jurassic; 3. Lower Carboniferous Hongliuyuan Formation; 4. Late Hercynian medium- to coarse-grained biotite granite; 5. Late Hercynian medium- to coarse-grained porphyritic biotite granite; 6. Hercynian medium- to fine-grained biotite granodiorite; 7. Hercynian micro- and fine-grained diorite; 8. Diabase dikes / diabase porphyry dikes; 9. Quartz veins; 10. Fine-grained granite veins; 11. Sandstone-type uranium mineralization points; 12. Hydrothermal uranium mineralization points and mineral occurrences and their numbers; 13. Uranium anomalies; 14. Gold mineralization points; 15. Copper anomalies; 16. Tungsten-tin anomalies; 17. Iceland spar anomalies; 18. Compressional / compressional-torsional faults and their occurrence; 19. Faults of unknown nature. 20. Marble; 21. Medium- to coarse-grained granite; 22. Porphyritic granite; 23. Albitized granite; 24. Fault; 25. Tectonic fracture zone; 26. Albitization; 27. Hematite mineralization; 28. Chloritization; 29. ​​Carbonatization; 30. Uranium orebody; 31. Uranium mineralized body; 32. Uranium anomaly; 33. Drill hole location and number. Detailed Implementation

[0023] The following detailed description of a specific embodiment of the present invention is provided in conjunction with the accompanying drawings. However, it should be understood that the scope of protection of the present invention is not limited to the specific embodiment.

[0024] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the technical solution of this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0025] In the description of the embodiments of the present invention, unless otherwise stated, "a plurality of" means two or more.

[0026] Example 1: like Figure 1 As shown in the figure, this embodiment provides a method for delineating albite uranium ore bodies in porphyritic granite. The method is carried out in four progressive stages, with the target geological body range gradually narrowing in each stage and the control accuracy gradually improving.

[0027] The first-scale geological survey is used to obtain the spatiotemporal distribution patterns and fault structures of igneous rocks in the mining area. Then, based on the igneous rock lithofacies classification results, the distribution range of porphyritic granite in the mining area is delineated.

[0028] The first-scale geological survey is a macro-scale investigation conducted throughout the entire mining area. Its purpose is to identify porphyritic granite, a favorable ore-bearing rock body genetically related to albite-uranium mineralization, from the entire mining area. The spatiotemporal distribution pattern of igneous rocks refers to the overall characteristics of the surface exposure location, exposure range, formation time, and rock species arrangement of different igneous rock types within the mining area. Fault structures refer to the structural features such as faults and folds that control the development of igneous rocks. The occurrence and distribution of igneous rocks are usually controlled by the fault structure system. The intersection of main and secondary faults often constitutes the dominant channels and reservoir spaces for magma intrusion, cooling, and consolidation. Based on the spatiotemporal distribution pattern of igneous rocks and fault structure information, lithofacies classification is performed according to the formation environment, rock structure, mineral composition, and degree of crystallization of igneous rocks. This divides the igneous rocks within the mining area into different lithofacies units. Then, based on the specific lithological characteristics of the porphyritic granite, the distribution range of the porphyritic granite is delineated in the lithofacies classification results. The delineation of the distribution range of porphyritic granite allows subsequent alteration screening work to focus on ore-bearing rock masses, avoiding the blind pursuit of high-cost, detailed exploration of the entire mining area.

[0029] Within the distribution range of porphyritic granite, a second-scale surface geological survey was conducted to preliminarily screen albite alteration anomaly zones. Combined with underground geophysical surveys, the range of underground concealed albite alteration was identified. Then, through vertical control of geological measured profiles and verification of authenticity by micro-rock and mineral identification, the three-dimensional spatial distribution of the albite alteration zone was delineated.

[0030] The second-scale surface geological survey is a more detailed surface investigation conducted within the delineated distribution area of ​​porphyritic granite than the first-scale survey. It is used to conduct a full-coverage screening of the entire porphyritic granite area and preliminarily identify surface albite alteration anomalies. Since surface surveys can only obtain shallow information and have limited ability to identify deep, concealed, and weakly developed albite alteration features, subsurface geophysical surveys are introduced based on the surface screening. The differences in physical properties between altered rock bodies and fresh granite bodies are used to identify the extent of concealed subsurface albite alteration. The geophysical survey results complement the surface screening results, jointly constituting information on the planar and deep distribution of the albite alteration zone. Based on this, vertical control is achieved through geologically measured profiles. Rock samples are systematically collected along the profiles and microscopic mineral identification is performed to verify the degree of albite development, mineral replacement mechanisms, and formation stages, eliminating false surface alteration anomalies, and ultimately forming a three-dimensional spatial distribution of the albite alteration zone in both planar and vertical directions. This phase organically combines surface geological surveys, underground geophysical measurements, profile vertical control, and microscopic rock and mineral identification. Through cross-validation of multi-source data, the accuracy of delineating the three-dimensional spatial distribution of albite alteration zones is significantly improved.

[0031] Within the albite alteration zone, the surface boundaries and development characteristics of the shallow mineralization alteration zone are first obtained through surface trenches. Then, the deep drilling project with the first exploration grid is deployed to trace the vertical extension of the ore body. The basic morphology of the uranium ore body is determined by cross-verification results of macroscopic uranium grade testing of core samples and micromineralogical testing of mineralized rocks.

[0032] Albitization alteration zones are the core favorable spaces for uranium mineralization, but alteration zones are not equivalent to uranium ore bodies. Further investigation within the alteration zones is needed to verify the actual development of uranium mineralization. Surface trenches are used to expose shallow mineralization alteration zones. By removing the surface overburden and weathered layers, the surface boundaries and development characteristics of these zones are directly obtained, providing geological basis for the layout of deep drilling projects. Deep drilling projects in the first exploration grid are used to trace the vertical extension characteristics of uranium ore bodies and obtain deep mineralization information. Macroscopic uranium grade tests are conducted on the drilled cores to obtain uranium element content data at a macroscopic scale, quantifying the mineralized and non-mineralized sections. Simultaneously, micromineralogical tests are conducted on the mineralized rocks to analyze the uranium element occurrence state and albite replacement characteristics at a microscopic scale. Cross-validation of macroscopic and microscopic tests can mutually verify uranium mineralization information at different scales. Microscopic mineralogical tests can eliminate false mineralization anomalies formed by shallow weathering, while macroscopic grade data can quantitatively define the boundary location of the ore body. The combination of the two makes the determination of the basic morphology of uranium ore bodies more reliable.

[0033] Within the basic morphology of the uranium ore body, a second exploration network of intensified drilling was deployed, and the ore body boundary was iteratively corrected based on the core test results of the intensified drilling, ultimately delineating the true development morphology of the uranium ore body.

[0034] The basic morphology of the uranium orebody obtained from the first exploration grid drilling project is limited by the relatively sparse engineering control spacing, which may lead to boundary deviations in sections where the orebody boundaries are blurred and mineralization thickness and grade vary significantly. The second exploration grid infiltration drilling project supplements the basic morphology of the uranium orebody by deploying additional drilling within this range, using a denser engineering control spacing to precisely delineate the orebody boundaries. Based on the core test results from the infiltration drilling project, the initially delineated orebody boundaries are iteratively corrected to eliminate the morphological distortion caused by the sparse exploration grid, ultimately determining the true developmental form of the uranium orebody.

[0035] In this embodiment, the first scale is larger than the second scale, and the first exploration grid density is larger than the second exploration grid density.

[0036] The term "first-scale greater than second-scale" refers to the fact that the coverage area of ​​a single geological survey at the first scale is greater than that at the second scale (surface geological survey). Specifically, the first-scale geological survey conducts a macroscopic investigation of the entire mining area, while the second-scale surface geological survey focuses on the distribution area of ​​porphyritic granite for detailed investigation. Similarly, the term "first-scale greater than second-scale" means that the spacing between adjacent engineering sections in the first-scale survey is greater than that in the second-scale survey. This means that the first-scale survey uses a relatively sparse spacing between engineering sections to initially control the ore body, while the second-scale survey uses a relatively dense spacing between engineering sections to refine the ore body boundaries. The four stages constitute a progressively advancing exploration process: the first stage delineates the distribution area of ​​porphyritic granite across the entire mining area; the second stage delineates the three-dimensional spatial distribution of the albite alteration zone within the porphyritic granite distribution area; the third stage determines the basic morphology of the uranium ore body within the albite alteration zone; and the fourth stage delineates the actual development morphology of the uranium ore body within the basic morphology range. The survey objects in each stage are a subset of the delineation results of the previous stage. The survey accuracy increases progressively as the scope shrinks. The stages are intrinsically related and inseparable, together forming a complete delineation method from the mining area scale to the ore body scale.

[0037] It should be noted that this embodiment is only used to explain the technical solution of the present invention and is not intended to limit the scope of protection of the present invention. The specific values ​​of the first scale, the second scale, the first exploration grid size, and the second exploration grid size can be adaptively adjusted according to the actual geological conditions of the mining area, the requirements of the exploration stage, and the accuracy requirements, as long as the progressive reduction relationship of the first scale being greater than the second scale and the first exploration grid size being greater than the second exploration grid size is satisfied.

[0038] Example 2: Based on Example 1, the first-scale regional geological survey includes three parallel methods: remote sensing image interpretation, first-scale route geological survey, and fault structure occurrence measurement and statistics.

[0039] Remote sensing image interpretation is used to initially extract macroscopic distribution information of rock masses and structures. Specifically, remote sensing image data matching the mining area is first collected, and radiometric and geometric correction preprocessing is completed. Then, remote sensing interpretation markers of lithology and alteration are established in conjunction with regional geological data. Rock mass and alteration information are extracted through human-computer interaction, and anomalous areas are initially delineated. After field verification and correction of interpretation errors, standardized remote sensing interpretation results are formed. The advantage of remote sensing image interpretation is that it can cover the entire mining area in a relatively short time, grasp the overall distribution pattern of rock masses and structures from a macroscopic perspective, and provide directional guidance for the route layout of subsequent ground survey work.

[0040] The first-scale route geological survey is used to confirm lithological types, rock mass occurrence characteristics, and geological boundaries in the field. The first scale is 1:10,000. As a specific implementation method, the 1:10,000 route geological survey can be conducted by laying out the exploration route according to a standard grid pattern of 500m main line spacing and 80 to 100m observation point spacing. High-precision satellite positioning equipment is used to complete the precise positioning and coordinate acquisition of the route and observation points. A full-coverage route tracing method is adopted to conduct field surveys, systematically observing and recording regional lithological types, rock mass occurrence characteristics, alteration development, and changes in geological boundaries. The spatial locations of various geological bodies and anomalies are accurately marked, and representative rock samples are collected. After the fieldwork is completed, the geological logging data is compiled, geological boundaries are corrected, and a basic geological sketch is prepared based on the sample test results, initially clarifying the overall distribution pattern of regional rock masses, alteration, and geological structures.

[0041] Fracture structure attitude measurement and statistics are used to clarify the tectonic control of rock. In practice, high-precision positioning equipment is used to locate the fault outcrops, and geological compasses are used to measure the fault strike, dip, dip angle and other attitude parameters. The scale, extension characteristics, cutting relationships and filling alteration characteristics of the faults are systematically observed and recorded. Typical fault points are numbered, archived and their coordinates are collected. After the measured data are uniformly sorted, the distribution patterns of fault attitudes are classified and statistically analyzed to form a standardized fracture structure statistical data table.

[0042] Remote sensing image interpretation, first-scale route geological surveys, and fault structure occurrence measurement and statistics work together to support subsequent igneous rock lithofacies classification. Remote sensing image interpretation provides a macroscopic distribution framework of rock masses and structures, route geological surveys provide on-site lithological confirmation and geological boundary marking, and fault structure occurrence measurement and statistics provide quantitative constraints on tectonic-controlled rocks. The geological information obtained from these three sources from different perspectives complements and corroborates each other, enabling the igneous rock lithofacies classification work to be based on multi-source data and avoiding lithofacies classification errors caused by the incompleteness of information from a single method.

[0043] Combination Figure 2 The geological map of the Jinchang area shows the distribution of the following tectonic features within the mining area: Quaternary Holocene 1, Lower Jurassic 2, Lower Carboniferous Hongliuyuan Formation 3, Late Hercynian medium- to coarse-grained biotite granite 4, Late Hercynian medium- to coarse-grained porphyritic biotite granite 5, Hercynian medium- to fine-grained biotite granodiorite 6, Hercynian micro- and fine-grained diorite 7, diabase dikes / diabase porphyry dikes 8, quartz veins 9, fine-grained granite veins 10, sandstone-type uranium mineralization points 11, hydrothermal uranium mineralization points and mineral occurrences and their numbers 12, uranium anomalies 13, gold mineralization points 14, copper anomalies 15, tungsten-tin anomalies 16, Iceland spar anomalies 17, compressive / compressive-torsional faults and their occurrences 18, and faults of unknown nature 19. Among these, fault structure 18 has a significant controlling effect on the spatial distribution of magmatic rocks, and porphyritic granite 4 is exposed in large, continuous areas in the structurally stable central section of the rock mass. Figure 2It can be seen that multiple fault structures form a network that cuts through the rock mass. The occurrence and distribution of magmatic rocks are strictly controlled by the fault structure system. The intersection of the main faults and secondary faults constitutes the dominant channels and reservoir spaces for magma intrusion, cooling, and consolidation. The fault structures not only control the spatial distribution boundaries of magmatic rocks, but the intensity of their tectonic activity also directly affects the scale of rock mass development. At the same time, they provide favorable geological conditions for later albite alteration and uranium mineralization.

[0044] Based on the spatial and temporal distribution patterns and fault structure information of igneous rocks, lithofacies classification is performed according to the formation environment, rock structure, mineral composition, and degree of crystallization of igneous rocks, resulting in the creation of igneous lithofacies diagrams. The formation environment of igneous rocks refers to the geological background and temperature and pressure conditions during the cooling and solidification of magma. Rock structure refers to the size, shape, and arrangement of mineral grains in the rock. Mineral composition refers to the types and amounts of various minerals in the rock. Degree of crystallization refers to the completeness of mineral crystallization in the rock. These characteristics collectively determine the lithofacies classification of igneous rocks. Quantitative thresholds such as structural parameters, mineral content, and degree of crystallization can distinguish different lithofacies units, clarifying the spatial distribution range and physicochemical lithological differences of each lithofacies.

[0045] The distribution range of porphyritic granites is delineated based on their unique lithological characteristics in magmatic lithofacies diagrams. These characteristics include porphyritic texture, characteristic phenocryst mineral assemblages, and structural features that distinguish them from other granitic rocks. After constructing the magmatic lithofacies diagram based on geological point data and lithological characteristics, the specific distribution range of porphyritic granites is selected and delineated within the diagram. Furthermore, their aggregation and extension patterns are summarized based on the regional rock mass occurrence characteristics.

[0046] After delineating the distribution range of the porphyritic granite, the second-scale surface geological survey, namely the second-scale route geological survey at 1:5000, was conducted to comprehensively screen for surface albite alteration anomalies within the porphyritic granite area. As a specific implementation method, the 1:5000 route geological survey can be laid out with a standard grid spacing of 200m between the main line and 30-50m between observation points, using the magmatic facies distribution map as the base map to conduct a comprehensive survey of the entire porphyritic granite area. Through surface route tracing and outcrop characteristic observation, the lithological characteristics, alteration types, surface outcrop morphology, and contact relationships of the rock mass are systematically recorded. This allows for the preliminary screening of alteration anomaly areas within the region and precise identification of potential albite alteration development zones, thus defining the core operational area for subsequent refined exploration work.

[0047] Geophysical exploration, specifically induced polarization (IP) gradient detection, utilizes survey lines laid out based on alteration anomaly zones identified through a second-scale geological survey. This method is used to detect deep, concealed alteration and refine alteration boundaries, providing data support for the scientific layout of subsequent geological profiles. IIP gradient detection identifies concealed subsurface alteration types by utilizing the difference in electrical parameters between altered rock masses and fresh granite. The survey lines are laid out based on the alteration anomaly zones identified through the second-scale geological survey, rather than being uniformly spread across the entire porphyritic granite area. This concentrates the geophysical workload on the alteration anomaly zones, improving detection efficiency and cost-effectiveness. The deep electrical parameter characteristics obtained through geophysical exploration can compensate for the limitations of surface surveys, which only provide shallow information, and refine the alteration boundary range, providing data support for the scientific layout of subsequent geological profiles.

[0048] This embodiment concretizes the implementation methods and scale values ​​of the first-scale regional geological survey and the second-scale surface geological survey, as well as the specific operations for delineating the distribution range of porphyritic granite through igneous lithofacies classification. This provides sufficient subordinate support for the higher-level concepts of the first-scale geological survey and the second-scale surface geological survey in Embodiment 1. The functional division and synergistic relationship among remote sensing image interpretation, route geological survey, and fault structure occurrence measurement and statistics, as well as the quantitative indicators for lithofacies classification, together constitute a precise delineation path from the entire mining area to the distribution range of porphyritic granite.

[0049] Example 3: Based on Example 1, this example further elaborates on the specific implementation method of combining second-scale surface geological surveys and underground geophysical surveys to identify the range of concealed albite alteration, as well as the specific operations of vertical control of geological measured profiles and verification of the authenticity of micro-rock and mineral identification.

[0050] Using the albite alteration anomaly zone identified by the second-scale surface geological survey as the deployment of probe lines and observation points, the electrical parameter characteristics of the rock mass are obtained by utilizing the principle of electrical detection.

[0051] The second-scale surface geological survey, through route tracing and outcrop observation within the distribution area of ​​porphyritic granite, preliminarily screened out surface albite alteration anomaly zones. These anomaly zones form the basis for geophysical survey deployment. Geophysical survey lines and observation points are not evenly distributed across the entire porphyritic granite area, but rather concentrated in the alteration anomaly zones and their surrounding extensions. This is because surface alteration anomaly zones usually have spatial correlations with deep alteration forms; concentrating geophysical work in these anomaly zones significantly improves detection efficiency and cost-effectiveness.

[0052] Geophysical surveys utilize the principle of electrical detection to obtain the electrical parameters characteristic of rock masses. Specifically, by supplying current underground and measuring the surface potential distribution, electrical parameters reflecting the conductivity and polarization characteristics of the rock mass can be obtained. Altered rock masses differ from fresh granite masses in mineral composition, pore structure, water content, and the amount of conductive minerals. These differences are reflected in electrical parameters, thus providing a physical basis for identifying concealed underground alteration forms.

[0053] As one specific implementation method, electrical parameters can include apparent polarizability and apparent resistivity. Apparent polarizability reflects the strength of the induced polarization effect produced by the rock mass under the action of an electric field, while apparent resistivity reflects the degree to which the rock mass impedes current conduction. After obtaining the electrical parameter data for the entire region, statistical methods can be used to determine the anomaly thresholds. For example, after removing extremely high values ​​from the physical property data for the entire region, a normal distribution can be statistically analyzed to calculate the mean and standard deviation. The lower limit of polarizability anomalies can be determined by adding twice the standard deviation to the mean, and the lower limit of resistivity anomalies can be determined by subtracting twice the standard deviation from the mean.

[0054] Based on the differences in electrical parameters, altered rock bodies can be distinguished from fresh granite bodies, and the range of deep-seated and weakly developed albite alteration can be delineated.

[0055] After obtaining the electrical parameter characteristics of the rock mass, altered rock masses are distinguished from fresh granite masses based on the differences in electrical parameters. Fresh granite masses usually have relatively stable background values ​​of electrical parameters, while albite-altered rock masses, due to the alteration of the mineral composition and structure of the rock by albite replacement, will have electrical parameters that deviate from the background values.

[0056] From the perspective of electrical response characteristics, albite alteration anomalies typically exhibit a gently sloping planar distribution with medium to low resistivity and medium to high polarization. The medium to low resistivity characteristic is related to the changes in rock porosity and water content after feldspar minerals are replaced by albite during alteration, while the medium to high polarization characteristic is related to the local enrichment of conductive minerals such as sulfides in the altered rock mass. The gently sloping planar distribution reflects the spatial characteristic of albite alteration zones, which are mainly distributed in planar and banded patterns.

[0057] It should be noted that electrical anomalies are not necessarily caused by albite alteration. Fracture zones typically exhibit narrow, banded anomalies with extremely low resistivity and high polarization, while silicification alteration shows high resistivity and low polarization. The electrical response characteristics of these interfering bodies differ from those of albite alteration. By constructing a multi-parameter discrimination system based on electrical properties and geological parameters, combined with albite content, geochemical indicators, and lithofacies zoning information, interfering anomalies can be comprehensively screened out, and the extent of deep, concealed, and weakly developed albite alteration can be accurately delineated.

[0058] The aforementioned geophysical measurements overcome the limitation of surface surveys in identifying deep alteration features. Surface surveys can only obtain shallow information and have limited ability to identify albite alteration features below the overburden or weakly developed. In contrast, electrical probing can penetrate the overburden to obtain deep information, extending the delineation of albite alteration range from the two-dimensional surface to the three-dimensional subsurface space.

[0059] Based on the characteristics of the internal electrical parameters of the rock mass, a third-scale geological survey profile was established, with a scale of 1:2000.

[0060] The electrical parameters obtained from geophysical surveys provide data support for the scientific layout of geological survey profiles. These profiles are not uniformly distributed throughout the porphyritic granite distribution area, but rather selected based on electrical parameter characteristics in key locations such as areas of concentrated albite alteration and transitional zones between different alteration intensities. The third scale is 1:2000, which, compared to the first scale of 1:10000 and the second scale of 1:5000, further improves the accuracy of profile measurements, enabling a detailed depiction of the alteration intensity, mineral composition variations, and rock structure differences in different sections of porphyritic granite.

[0061] Through precise profile measurement and detailed stratification, the number of layers, width, and occurrence state of albite alteration zones can be precisely delineated, and the development and variation patterns of alteration in the horizontal and vertical directions can be fully recorded. The vertical information obtained from profile measurement and the deep information obtained from geophysical surveys corroborate each other, jointly constructing a spatial development system of albite alteration.

[0062] Rock samples were collected along the measured profile in different alteration intensity zones and spatial strata. Rock thin sections were prepared for microscopic rock and mineral identification to determine the degree of development of albite alteration, mineral replacement mechanism and formation period. False alteration anomalies on the surface were eliminated, and the three-dimensional spatial distribution of albite alteration zones was finally formed.

[0063] Rock samples were not collected randomly, but rather along the measured profile in different alteration intensities and spatial stratigraphic systems. This was done to obtain a sample assemblage that could represent the overall development characteristics of the alteration zone, avoiding judgment bias caused by a single sampling location.

[0064] After the collected rock samples are prepared into thin sections, microscopic rock and mineral identification is performed. Microscopic rock and mineral identification involves observing the optical properties, morphological characteristics, and replacement relationships of minerals in the thin sections under a polarizing microscope, thereby determining the degree of albite alteration, the mineral replacement mechanism, and the formation stage.

[0065] During microscopic identification, albite is easily confused with minerals such as plagioclase, quartz, and sericite. As a specific method, preliminary differentiation can be made based on optical characteristics such as polysynthetic twinning, extinction type, and interference colors. For example, albite and plagioclase both belong to the plagioclase series, but they differ in the morphology of polysynthetic twinning and the extinction angle. When optical characteristics are insufficient for accurate differentiation, quantitative determination can be made by measuring the An grade of plagioclase using an electron probe microanalysis (EPMA). Plagioclase with an An grade below a certain threshold is altered albite, while those above this threshold are plagioclase.

[0066] A key function of microscopic rock and mineral identification is the verification of authenticity, namely, eliminating false alteration anomalies from the surface. Some alteration anomalies identified during surface surveys may be caused by supergene weathering, secondary mineral staining, or other non-albite alteration factors. These false anomalies cannot be observed with true albite replacement structures at the microscopic scale. Microscopic identification can reveal the true development characteristics of albite alteration, thus eliminating false anomalies from the alteration zone delineation results.

[0067] By combining the results of field geological exploration, geophysical data detection, high-precision profile measurement, and indoor rock and mineral identification, we can obtain the planar distribution characteristics, vertical development patterns, and strong and weak enrichment characteristics of albite alteration rocks, and ultimately form the three-dimensional spatial distribution of albite alteration zones.

[0068] As a specific example, the above process delineated three albite alteration zones in a certain mining area. The overall orientation is predominantly steeply dipping, with dips ranging from 110° to 130° and dip angles from 65° to 80°. The width of each zone ranges from 2 to 8 meters, and the length extends from 120 to 350 meters. The alteration zones are distributed in discontinuous bands and beaded patterns in plan view, with the largest alteration scale observed in structurally complex areas. Vertically, they exhibit distinct stratification characteristics: shallow alteration is intense and wide, while deeper alteration gradually weakens and narrows, showing a stratified development pattern of gentler upper sections and narrower lower sections.

[0069] This embodiment organically connects four stages: surface screening, geophysical identification, profile control, and microscopic verification, forming a multi-source data cross-verification process for delineating alteration zones in three dimensions. Surface screening provides the planar location of alteration anomalies, geophysical identification provides the extent of deep concealed alteration, profile control provides the vertical alteration development patterns, and microscopic verification provides the final basis for determining the authenticity of alteration. The data from these four stages complement and corroborate each other, significantly improving the accuracy of delineating the three-dimensional spatial distribution of albite alteration zones and providing quantitative geological evidence for subsequent fine delineation of uranium ore bodies.

[0070] Example 4: Based on Example 1, this example further elaborates on the specific implementation logic of cross-verification between macroscopic testing of uranium grade in core samples and micromineralogical testing of mineralized rocks to determine the basic morphology of uranium ore bodies, as well as the specific means of using electron probe microanalysis for micromineralogical testing.

[0071] By analyzing the mineral composition, uranium occurrence state, and albite alteration characteristics of the mineralized rocks through micromineralogical tests, the genetic correspondence between uranium mineralization and albite alteration was verified, and false mineralization anomalies caused by shallow weathering were eliminated.

[0072] Micromineralogical testing analyzes mineralized rock samples obtained from drilling operations. Unlike macroscopic testing, which focuses on the overall uranium content of the rock, microscopic testing focuses on the mineral scale, analyzing the mineral composition, uranium occurrence state, and albite replacement characteristics of the mineralized rock. Mineral composition analysis is used to identify the types and contents of major and minor minerals in the ore; uranium occurrence state analysis is used to determine whether uranium exists as an independent uranium mineral or as an isomorphous occurrence within other minerals; and albite replacement characteristic analysis is used to determine the degree, mode, and timing of albite replacement of the protolith minerals.

[0073] Micromineralogical testing plays a crucial role in cross-validation mechanisms, verifying the authenticity of mineralization. A genetic correspondence exists between uranium mineralization and albite alteration; uranium mineralization is a product of albite alteration reaching a certain stage, and uranium minerals typically accumulate along albite replacement sites. Microscopic testing can verify the validity of this genetic correspondence: if uranium minerals are indeed present in albite replacement sites, and uranium mineralization and albite alteration are spatially and genetically consistent, then the mineralization information is genuine. If the uranium content anomaly is not genetically related to albite alteration but is caused by secondary enrichment of uranium during shallow weathering, then the anomaly is a false mineralization anomaly and should be excluded from ore body delineation. False mineralization anomalies formed by shallow weathering also manifest as increased uranium content in macroscopic grade tests. Macroscopic data alone are insufficient to distinguish them from genuine mineralization; microscopic testing, by observing the uranium occurrence state and mineral replacement relationships, can differentiate them at the genetic level.

[0074] Micromineralogical testing employs electron probe microanalysis to measure the mineral composition, elemental occurrence, and mineral alteration characteristics of the core.

[0075] Electron probe microanalysis (EPMA) is a micro-area in-situ analytical technique that uses a focused electron beam to bombard the sample surface, exciting characteristic X-rays of elements in the sample. By analyzing the wavelength and intensity of these characteristic X-rays, the types and amounts of elements within a micro-area can be determined. EPM can achieve spatial resolution down to the micrometer level, enabling the acquisition of mineral composition and elemental occurrence information at the scale of a single mineral crystal.

[0076] In practice, representative mineralized rock samples selected from drilling cores are prepared into probe slides for targeted analysis of albite alteration sites and uranium mineral occurrence sites using electron probe microanalysis (EPMA). EPM can identify albite alteration characteristics, such as measuring changes in the content of anorthoclase in plagioclase to determine the degree of albite development; it can identify the types and locations of uranium minerals, determining whether they are independent or dispersed within other minerals; and it can observe mineral replacement relationships to determine the sequence and formation period of albite alteration. The microscopic information obtained from EPM complements the optical information obtained from micromineral identification. Micromineral identification provides an overall assessment of mineral types and structures, while EPM provides quantitative data on mineral composition and elemental occurrence. The combination of both makes the judgment criteria of micromineralogical testing more comprehensive.

[0077] By combining the content data of uranium grade macroscopic test of core samples, mineralized enrichment sections and non-mineralized sections are quantitatively divided, the boundary of the ore body is accurately defined, and the basic spatial morphology of the uranium ore body is determined together.

[0078] Macroscopic testing of uranium grade in core samples involves determining the uranium content after segmenting drill core samples to obtain uranium grade distribution data along the borehole direction. Macroscopic testing serves a quantitative definition function in cross-validation mechanisms. Microscopic testing solves the qualitative determination of mineralization authenticity, but it cannot independently complete the quantitative delineation of orebody boundaries; the determination of orebody boundaries requires uranium grade content data as a basis.

[0079] In practical implementation, the evaluation can be conducted in stages, referring to general industrial indicators for uranium exploration. For example, the boundary grade of uranium ore can be taken as 0.05%, the minimum industrial grade can be taken as 0.05%, and the minimum mineable thickness and the thickness for removing interbedded rocks can be set at 0.7m. After sampling and testing the uranium content of different sections of the core according to the specifications, the uranium mineralization enrichment section, depletion section, and waste rock section are quantitatively divided according to the industrial indicators, accurately defining the ore body boundary, ore body thickness, and dynamic changes in grade throughout the entire section. It should be noted that the above industrial indicators are only a specific example, and can be adaptively adjusted according to the geological conditions of the mining area and the requirements of resource evaluation in actual applications.

[0080] The cross-validation logic of macroscopic and microscopic testing lies in the following: microscopic testing verifies the correspondence between uranium mineralization and albite alteration at the genetic level, eliminating false mineralization anomalies caused by shallow weathering, and ensuring that the mineralization information used in delineating the ore body is genuine; macroscopic testing quantitatively divides the mineralized enrichment zone and the non-mineralized zone at the content level, accurately defining the boundary of the ore body. Both methods obtain uranium mineralization information from different scales. The qualitative judgment results of microscopic testing provide the premise of truth or falsehood for the quantitative definition of macroscopic testing, while the quantitative data of macroscopic testing provides spatial positioning for the genetic determination of microscopic testing. The two methods mutually corroborate and complement each other, jointly determining the basic spatial morphology of the uranium ore body.

[0081] Combination Figure 3 The ZKJ25-7 borehole lithology columnar section shows the lithological stratification of the drill core, from top to bottom: light pinkish-red medium-coarse-grained granite ①, light pinkish-red breccia granite ②, grayish-white breccia marble ③, breccia granite with tectonic lenses ④, foliated zone ⑤, grayish-white breccia marble ⑥, grayish-white marble ⑦, kaolinized marble ⑧, serpentinized marble ⑨, kaolinized marble ⑩, breccia silicified zone ⑪, promylonitized zone ⑫, foliated zone ⑬, mylonitized zone ⑭, light pinkish-red medium-coarse-grained granite ⑮. Figure 3 It can be seen that the borehole traversed multiple fault zones, with complex lithological stratification and well-developed tectonic deformation phenomena such as fracturing, foliation, and mylonitization. These structurally weak areas provided favorable spaces for the enrichment of albite alteration and uranium mineralization. When conducting macroscopic uranium grade testing of the core, it is necessary to rationally divide the sampling sections according to lithological stratification and tectonic deformation characteristics, and to focus on and intensify sampling of mineralized alteration sections to ensure that the uranium grade data can accurately reflect the mineralization development.

[0082] This embodiment organically combines the genetic verification function of microscopic mineralogical testing with the quantitative definition function of macroscopic uranium grade testing from core samples, establishing a dual-scale cross-verification mechanism. This mechanism ensures that the determination of the basic morphology of uranium orebodies possesses both genetic reliability and content accuracy, avoiding the interference of false mineralization anomalies on orebody delineation when relying solely on macroscopic grade data, and also avoiding the limitation of failing to quantitatively delineate orebody boundaries when relying solely on microscopic testing.

[0083] Example 5: Based on Example 1, this example further elaborates on the triggering conditions, grid degree values, and iterative correction content of the second exploration grid densification drilling project.

[0084] Within the basic morphology of the uranium ore body, a second exploration grid of intensified drilling projects will be deployed, including: for key sections where the ore body boundaries are ambiguous, the mineralization thickness and grade variation gradient is greater than a preset threshold, and the mineralization continuity is uneven, a second exploration grid of intensified drilling projects will be deployed.

[0085] The first exploration grid drilling project, with its relatively sparse spacing, provides preliminary control of the uranium orebody. In sections with relatively simple orebody morphology and relatively uniform mineralization distribution, the basic orebody morphology obtained by the first exploration grid is sufficient to meet the delineation accuracy requirements. However, in key sections where orebody boundaries are ambiguous, mineralization thickness and grade variations are significant, and mineralization continuity is uneven, there is considerable room for inference regarding the orebody boundary positions between adjacent boreholes. The sparse grid makes it difficult to accurately depict the true strike of the orebody boundary and the spatial variation of mineralization thickness. Ambiguous orebody boundaries refer to unclear pinch-out locations between adjacent ore-bearing and non-ore-bearing boreholes, or irregular curvature of the orebody boundary lines along strike and dip that sparse drilling cannot effectively control. Mineralization thickness and grade variations exceeding preset thresholds indicate that the difference in mineralization thickness or uranium grade between adjacent boreholes exceeds the preset allowable range, suggesting drastic spatial variations in the orebody within that section. Uneven mineralization continuity refers to the discontinuous distribution of ore bodies along their strike or dip, with localized areas containing barren rock or mineralized depleted sections. Sparse drilling patterns make it difficult to determine the true continuity of the ore body. In these critical sections, supplementary drilling with a second exploration grid can reduce the control spacing, significantly narrowing the inferred ore body boundary between adjacent boreholes, thereby improving the accuracy of controlling ore body boundaries and mineralization characteristics.

[0086] The first exploration grid is 80m × 80m, and the second exploration grid is 40m × 40m. The first exploration grid refers to a spacing of 80m between adjacent exploration lines and between adjacent boreholes on the exploration lines. The second exploration grid refers to a spacing of 40m between adjacent exploration lines and between adjacent boreholes on the exploration lines. The engineering density of the second exploration grid is four times that of the first exploration grid, meaning that the number of drilling operations within the same area is increased fourfold. It should be noted that 80m × 80m and 40m × 40m are only grid values ​​in one specific implementation. In actual applications, adjustments can be made according to the complexity of the ore body morphology, the uniformity of mineralization, and the requirements of the exploration stage, as long as the progressive density relationship of the first exploration grid being greater than the second exploration grid is maintained.

[0087] As a specific implementation method, the variation gradient of mineralization thickness and grade exceeding a preset threshold can be quantitatively determined using variation coefficients. The grade variation coefficient and thickness variation coefficient are statistical indicators reflecting the degree of spatial fluctuation in mineralization; a larger variation coefficient indicates more severe spatial fluctuations in mineralization. For example, when both the grade variation coefficient and thickness variation coefficient are greater than or equal to 80%, the section can be identified as a highly fluctuating and complex mineralization section, a critical section requiring additional in-depth drilling; when both the grade variation coefficient and thickness variation coefficient are less than 100%, the section can be identified as a moderately fluctuating mineralization section; and when both the grade variation coefficient and thickness variation coefficient are less than 80%, the section can be identified as a uniform and stable mineralization section. By quantitatively determining the variation coefficients, in-depth drilling projects can be concentrated in sections with the most severe mineralization fluctuations, avoiding unnecessary in-depth drilling in uniformly stable mineralization sections, thus improving the targeting and economy of exploration work.

[0088] The orebody boundary is iteratively corrected based on the core test results of the in-situ drilling project, including: iterative correction of the orebody's planar and vertical boundaries, orebody thickness, and grade distribution characteristics.

[0089] Core testing results obtained from infill drilling provide denser mineralization control data, which can be used to iteratively refine the initially delineated orebody boundaries. Refinement of the orebody's planar boundaries involves adjusting the position of the boundary lines on the horizontal plane based on the mineralization encountered in the infill boreholes, making the boundary lines closer to the actual pinch-out location of the orebody. Refinement of the orebody's vertical boundaries involves adjusting the position of the boundary lines on the cross-section based on the mineralization depth and mineralization thickness of the infill boreholes. Refinement of the orebody's thickness and grade distribution characteristics involves updating the orebody thickness contour maps and grade distribution maps based on the mineralization thickness and uranium grade data from the infill boreholes, allowing for a more accurate depiction of the orebody's thickness variations and spatial changes in grade.

[0090] When iteratively revising orebody boundaries, the connection rules for orebody delineation can be followed. For example, non-mineralized inclusions with a thickness of less than 0.7m within a single borehole are removed. That is, when a non-mineralized inclusion appears in a borehole with a thickness of less than 0.7m, it is not used as a basis for orebody interruption, but is incorporated into the mineralized section for unified delineation. Adjacent mineralized boreholes are connected straight along the strike and dip of the orebody. That is, when two adjacent boreholes both encounter mineralization, the orebody boundary is connected in a straight manner between them. Gradually decreasing grade transition sections are delineated by interpolation using percentage values ​​per meter. That is, when a transition section with gradually decreasing grade appears near the orebody boundary, the orebody boundary position is determined by interpolation using percentage values ​​per meter. The orebody boundary is broken when the spacing between non-mineralized boreholes exceeds the control grid size. That is, when the spacing between adjacent non-mineralized boreholes exceeds the control grid size, the orebody boundary is broken at that point. The above connection rules provide a unified operational standard for the iterative revision of orebody boundaries, avoiding inconsistencies in delineation results due to differences in subjective judgment among different operators.

[0091] As a specific example, after completing the first exploration grid of 80m×80m drilling in a certain mining area, the basic morphology of the uranium ore body was initially delineated, with the overall dip ranging from 110° to 130°∠65° to 80°. For the variable sections with ambiguous ore body boundaries and large grade fluctuations, a second exploration grid of 40m×40m intensified drilling was deployed. After intensified core sampling and testing, the ore body parameters were iteratively corrected. The updated overall dip of the ore body is now 115° to 125°∠68° to 78°, the actual ore body thickness is 1.5 to 5.2m, the industrial uranium grade is 0.06% to 0.31%, and the maximum vertical burial depth of the ore body is effectively controlled at 235m. The range of occurrence parameters of the ore body after infiltration correction is narrower than that of the preliminary delineation results. The ore body thickness and grade data are more accurate, indicating that infiltration drilling effectively corrects the ore body morphology distortion caused by sparse grid, and clearly presents the true development morphology of the ore body with discontinuous strips in the plane and alternating thickness in the vertical direction.

[0092] This embodiment organically combines the triggering conditions, grid density values, and iterative correction content of infiltration drilling to form a refined delineation process that integrates preliminary control of sparse grid density with iterative correction of infiltration grid density. The triggering conditions ensure that infiltration drilling is concentrated in key areas with the most intense mineralization fluctuations; the grid density values ​​ensure that the controlled density of the infiltrated drilling meets the requirements for fine boundary tracking; and the iterative correction content ensures that boundary deviations in the preliminary delineation results are systematically corrected. The combined effect of these three factors further improves the accuracy of delineating the true development morphology of uranium ore bodies based on the initial control of the first exploration grid density.

[0093] Example 6: Taking the Longshoushan mining area as a specific application scenario, the delineation process in the aforementioned embodiments was applied to the exploration of albite uranium ore bodies in the porphyritic granite of the mining area, fully demonstrating the entire process from mining area-scale investigation to fine delineation of ore bodies.

[0094] During the mining area-scale investigation phase, the spatial and temporal distribution patterns and fault structures of igneous rocks within the mining area were obtained through first-scale geological surveys. The igneous rocks in the mining area generally exhibit a concentrated distribution pattern in banded and massive forms, with uneven spatial distribution. Rock masses are mostly concentrated in areas of intense tectonic activity. Porphyritic granite is the dominant igneous rock in the mining area, with a stable overall distribution and a relatively large outcrop scale. Combined with... Figure 2Fault structures (18) have a significant controlling effect on the spatial distribution of igneous rocks. Multiple fault structures form a network that cuts through the rock mass. The intersection of main and secondary faults provides favorable channels and reservoir spaces for magma intrusion, cooling, and consolidation. Fault structures not only control the spatial distribution boundaries of igneous rocks, but the intensity of their tectonic activity also directly affects the scale of rock mass development. They also provide favorable geological conditions for later albite alteration and uranium mineralization. After classifying the lithofacies based on the formation environment, rock structure, mineral composition, and degree of crystallization of igneous rocks, the distribution range of porphyritic granite is delineated in the igneous lithofacies diagram based on the specific lithological characteristics of porphyritic granite. In the Longshoushan mining area, porphyritic granite is mainly concentrated in the tectonically stable central section of the rock mass, exposed over a large area, exhibiting the largest scale and best continuity. It is the main host rock mass for albite alteration and uranium mineralization in the area.

[0095] During the alteration screening stage, a preliminary screening of albite alteration anomalies was conducted within the distribution area of ​​porphyritic granite using a second-scale surface geological survey. This was combined with induced polarization (IPC) gradient detection to identify the extent of concealed albite alteration underground. Further verification was achieved through vertical control of geological profiles and microscopic rock and mineral identification, thus delineating the three-dimensional spatial distribution of the albite alteration zones. The albite alteration in the mining area is not uniformly developed across the entire porphyritic granite region; it is mainly concentrated and enriched along structurally weak and fractured sections within the rock mass. Overall, it is distributed in banded and discontinuous platy morphology, with unevenly narrow alteration bands and significant differentiation in intensity. The intensity of alteration can be quantitatively divided using the volume percentage of altered albite and the increase in whole-rock Na₂O. Weak albite alteration is characterized by a low volume percentage of altered albite, with a whole-rock Na₂O increase of 0.5% to 1.0%, and sporadic distribution of microcrystalline albite. Moderate albite alteration is characterized by a volume percentage of altered albite between 20% and 40%, occurring as spotted or veinlet aggregates. Strong albite alteration is characterized by a further increase in the volume percentage of altered albite, a whole-rock Na₂O increase of more than 2.5%, with the rock as a whole dominated by albite replacement and a large disappearance of the original minerals. Alteration is more extensive and continuous in tectonically complex areas, forming the main favorable alteration spaces for uranium mineralization in the area. Following the above alteration screening process, three albite alteration zones were delineated, with an overall near-steep dip, dipping from 110° to 130°, with dip angles from 65° to 80°, a single zone width of 2 to 8 m, and an extension length of 120 to 350 m. The alteration zones are distributed in discontinuous strips or beaded patterns in the plane, and have obvious stratification characteristics in the vertical direction. The shallow alteration is strong and wide, while the deep alteration gradually weakens and narrows in thickness, showing a stratified development characteristic of being wide and gentle at the top and converging at the bottom.

[0096] During the drilling verification phase, surface trenches were first used within the albite alteration zone to obtain the surface boundaries and development characteristics of the shallow mineralization alteration zone. Through systematic trenching and excavation, the width of the shallow mineralization alteration zone was precisely controlled to be 2.0 to 7.5 m, and its surface extension length to be 130 to 340 m. Based on the shallow mineralization development characteristics obtained from the trenching, a first exploration grid of 80 m × 80 m deep drilling was deployed to trace the vertical extension of the ore body. Vertical drilling confirmed the continuous vertical development of the ore body, effectively controlling its vertical burial depth from 0 to 210 m. Macroscopic uranium grade testing was conducted on the core samples obtained from the drilling. The results showed that the uranium grade in the industrial ore section was concentrated between 0.05% and 0.28%, with a thickness of 1.2 to 4.8 m. Simultaneously, representative mineralized core samples were selected for electron probe microanalysis to accurately identify the locations of albite alteration and uranium mineral occurrence, correcting shallow artifacts and anomalies. Figure 3 The data reveals the lithological stratification of the drill cores, including marble (20); medium- to coarse-grained granite (21); porphyritic granite (22); albite-altered granite (23); faults (24); tectonic fracture zones (25); albite alteration (26); hematite mineralization (27); chloritization (28); carbonatization (29); uranium orebodies (30); uranium mineralized bodies (31); uranium anomalies (32); and borehole locations and numbers (33). The boreholes traversed multiple fault zones, exhibiting complex lithological stratification with well-developed tectonic deformation phenomena such as fracturing, foliation, and mylonitization. These structurally weak areas provided favorable conditions for albite alteration and uranium mineralization enrichment. Cross-validation through macroscopic uranium grade testing of the cores and micromineralogical testing of the mineralized rocks determined the basic morphology of the uranium orebodies. The orebodies generally occur with a steep dip, ranging from 110° to 130°∠65° to 80°, exhibiting planar banded enrichment and vertical stratification.

[0097] During the infiltration and correction phase, a second exploration grid of 40m×40m was deployed within the basic morphological range of the uranium orebody. Additional infiltration drilling was conducted in variable sections with ambiguous orebody boundaries and large grade fluctuations, effectively tracing the edge extension characteristics of the orebody and correcting boundary deviations. Infiltrated core sampling and testing accurately distinguished between mineralized and unmineralized sections, iteratively correcting the orebody parameters. The updated overall orebody occurrence is 115° to 125°∠68° to 78°, the actual orebody thickness is 1.5 to 5.2m, the industrial uranium grade is 0.06% to 0.31%, and the maximum vertical burial depth of the orebody is effectively controlled at 235m. The range of orebody occurrence parameters after infiltration and correction is narrower than the initial delineation results, and the orebody thickness and grade data are more accurate, indicating that infiltration drilling effectively corrected the morphological distortion of the orebody caused by the sparse grid, clearly presenting the true development morphology of the orebody as discontinuous stripes in the plane and alternating thicknesses in the vertical direction.

[0098] This embodiment verifies the feasibility and effectiveness of the aforementioned delineation method using actual exploration data from the Longshoushan mining area. From investigating the distribution patterns of magmatic rocks at the mining area scale, to delineating the distribution range of porphyritic granite, then to delineating the three-dimensional spatial distribution of albite alteration zones, and finally to determining the basic morphology and finely delineating the actual developmental form of uranium orebodies, each stage of exploration work is interconnected and progressively advances, gradually narrowing the delineation range and improving the control precision. Actual exploration results show that this method can effectively delineate albite uranium orebodies in porphyritic granite under complex geological conditions, providing reliable technical support for the refined exploration and resource evaluation of alkali-alkaline metasomatic uranium deposits.

[0099] It should be noted that any parts not disclosed or specifically described in this invention are existing technology or conventional configurations, and their specific structures and working principles will not be elaborated further. In this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0100] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. It can be applied to various fields suitable for the present invention. Other modifications can be readily implemented by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and examples shown and described herein.

Claims

1. A method for delineating albite uranium ore bodies in porphyritic granite, characterized in that, include: The first-scale geological survey is used to obtain the spatiotemporal distribution patterns and fault structures of igneous rocks in the mining area. Then, based on the igneous rock lithofacies classification results, the distribution range of porphyritic granite in the mining area is delineated. Within the distribution range of the porphyritic granite, a second-scale surface geological survey was conducted to preliminarily screen the albite alteration anomaly zone. Combined with underground geophysical surveys, the range of underground concealed albite alteration was identified. Then, through vertical control of geological measured profiles and verification of authenticity by micro-rock and mineral identification, the three-dimensional spatial distribution of the albite alteration zone was delineated. Within the albite alteration zone, the surface boundary and development characteristics of the shallow mineralization alteration zone are first obtained through surface trenches. Then, the deep drilling project with the first exploration grid is deployed to trace the vertical extension of the ore body. The basic morphology of the uranium ore body is determined by cross-verification results of macroscopic uranium grade testing of core and micromineralogical testing of mineralized rocks. Within the basic morphological range of the uranium ore body, a second exploration grid of intensified drilling is deployed, and the ore body boundary is iteratively corrected based on the core test results of the intensified drilling, ultimately delineating the true development morphology of the uranium ore body. The first scale is larger than the second scale, and the first exploration grid density is larger than the second exploration grid density.

2. The method for delineating albite uranium ore bodies in porphyritic granite according to claim 1, characterized in that: The first-scale regional geological survey includes remote sensing image interpretation, first-scale route geological survey, and fault structure occurrence measurement and statistics. Among them, remote sensing image interpretation is used to initially extract macroscopic distribution information of rock masses and structures, first-scale route geological survey is used to confirm lithological types, rock mass occurrence characteristics and geological boundaries in the field, and fault structure occurrence measurement and statistics is used to clarify the tectonic control of rock laws. The three together support the subsequent magmatic rock lithofacies classification work. The second-scale surface geological survey is a second-scale route geological survey, used to screen for surface albite alteration anomalies with full coverage within the porphyritic granite range; the geophysical survey is induced polarization gradient detection, which lays out survey lines based on the alteration anomaly areas screened out by the second-scale geological survey, used to detect deep hidden alteration and refine alteration boundaries, providing data support for the scientific layout of subsequent geological measurement profiles. The first scale is 1:10000, and the second scale is 1:5000.

3. The method for delineating albite uranium ore bodies in porphyritic granite according to claim 1, characterized in that, The basic morphology of the uranium ore body was determined by cross-validation results of macroscopic uranium grade testing of core samples and micromineralogical testing of mineralized rocks, including: By analyzing the mineral composition, uranium occurrence state, and albite replacement characteristics of the mineralized rocks through micromineralogical tests, the genetic correspondence between uranium mineralization and albite alteration was verified, and false mineralization anomalies caused by shallow weathering were eliminated. By combining the content data of uranium grade macroscopic test of core samples, mineralized enrichment sections and non-mineralized sections are quantitatively divided, the boundary of the ore body is accurately defined, and the basic spatial morphology of the uranium ore body is determined together.

4. The method for delineating albite uranium ore bodies in porphyritic granite according to claim 3, characterized in that, The micromineralogical tests were performed using electron probe microanalysis to measure the mineral composition, elemental occurrence, and mineral alteration characteristics of the core.

5. The method for delineating albite uranium ore bodies in porphyritic granite according to claim 1, characterized in that, Preliminary screening of albite alteration anomalies was conducted through second-scale surface geological surveys, and the extent of concealed albite alteration was identified by combining these with underground geophysical surveys, including: Using the albite alteration anomaly zone identified by the second-scale surface geological survey as the deployment of probe lines and observation points, the electrical parameter characteristics of the rock mass are obtained by utilizing the principle of electrical detection. Based on the differences in electrical parameters, altered rock bodies can be distinguished from fresh granite bodies, and the range of deep-seated and weakly developed albite alteration can be delineated.

6. The method for delineating albite uranium ore bodies in porphyritic granite according to claim 5, characterized in that, Based on vertical control of geological profiles and verification through microscopic rock and mineral identification, the three-dimensional spatial distribution of the albite alteration zone was delineated, including: Based on the electrical parameter characteristics of the rock mass, a third-scale geological measurement profile is laid out, the third scale being 1:2000; Rock samples were collected along the measured profile in different alteration intensity zones and spatial strata. Rock thin sections were prepared for microscopic rock and mineral identification to determine the degree of development of albite alteration, mineral replacement mechanism and formation period. False alteration anomalies on the surface were eliminated, and the three-dimensional spatial distribution of albite alteration zones was finally formed.

7. The method for delineating albite uranium ore bodies in porphyritic granite according to claim 1, characterized in that, Within the basic morphological range of the uranium ore body, a second exploration grid of intensified drilling is deployed, including: For key sections where the ore body boundaries are ambiguous, the mineralization thickness and grade variation gradient is greater than the preset threshold, and the mineralization continuity is uneven, additional intensified drilling projects with the second exploration grid are deployed. The first exploration grid is 80m×80m, and the second exploration grid is 40m×40m.

8. The method for delineating albite uranium ore bodies in porphyritic granite according to claim 7, characterized in that, The iterative correction of the ore body boundary based on the core test results of the encrypted drilling project includes: Iterative correction of the ore body's planar and vertical boundaries, ore body thickness, and grade distribution characteristics.

9. The method for delineating albite uranium ore bodies in porphyritic granite according to claim 1, characterized in that, The distribution range of porphyritic granite, obtained from the first-scale geological survey, includes: Based on the formation environment, rock structure, mineral composition, and degree of crystallization of igneous rocks, lithofacies are classified and igneous lithofacies diagrams are drawn. The distribution range of the porphyritic granite is delineated based on the specific lithological characteristics of the porphyritic granite in the magmatic lithofacies diagram.

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