A method for adapting multi-source collaborative geological survey and mineral resource potential evaluation in the Antarctic ice-covered area

Abstract

The application discloses a method for adapting to multi-source collaborative geological survey and mineral resource potential evaluation in the Antarctic ice-covered area, and belongs to the technical field of polar geological exploration. In view of the technical problem of low imaging accuracy under the Antarctic ice, the application constructs a four-layer collaborative detection system of space-based, aviation, ground and under-ice; establishes a complete link of seismic full-wave field imaging, adopts reverse time migration (RTM) to realize high-resolution imaging of less than 5 m; establishes a complete reverse time migration imaging processing link, constructs a four-dimensional ice cover interference correction model, adopts a D-S evidence theory multi-source data fusion algorithm, and constructs a four-dimensional interference correction model of ice layer thickness, ice flow velocity, temperature gradient and moraine content; the D-S evidence theory multi-source fusion algorithm is adopted, a quantitative discrimination standard is established based on Vp / Vs, Poisson's ratio and anisotropy, and the target area prediction accuracy is greater than or equal to 85%. All parameters and formulas of the application are fully disclosed, and can be widely applied to the geological survey and mineral evaluation under the Antarctic ice.

Description

Technical Field

[0001] This invention relates to the field of polar geological exploration technology, specifically to a method for multi-source collaborative geological surveys and mineral resource potential evaluation adapted to Antarctic ice-covered areas. Background Technology

[0002] Over 99.8% of the Antarctic continent is covered by a kilometer-thick ice sheet, with only a small area at the edges exposing bedrock. The natural environment is characterized by extremely low temperatures, extremely strong winds, polar days and nights, and complex terrain. This presents challenges such as logistical difficulties, strict limitations on the scope and duration of field operations, difficulty in deploying large-scale ground engineering projects, and high failure rates of conventional equipment due to low temperatures. Existing conventional terrestrial geological survey methods, relying on large-scale manual mapping, intensive ground geophysical and geochemical exploration, and extensive drilling, cannot be directly applied to the Antarctic ice-covered region.

[0003] Current Antarctic geological research and resource assessment technologies suffer from the following core technological deficiencies: First, subglacial geological imaging suffers from insufficient precision and limited resolution. Existing technologies primarily employ satellite remote sensing, airborne gravity, magneto, and electromagnetic methods, achieving a spatial resolution of only 50-100 meters, which is insufficient to identify the fine structure and small-scale mineralization anomalies of subglacial bedrock. Traditional X-ray-based seismic imaging methods are limited by approximate assumptions, only obtaining a one-dimensional velocity model and failing to provide information on lateral heterogeneity. Their ability to characterize the internal stratification of ice sheets, ice-rock interface undulations, and bedrock heterogeneity is severely inadequate, resulting in a target area prediction accuracy of only around 45%.

[0004] Second, there is a lack of quantitative inversion mechanisms for ice sheet physical parameters. Current technologies have not established quantitative inversion methods for key physical parameters such as ice sheet porosity, density, and anisotropy, making it impossible to distinguish between ice sheet interference and genuine bedrock anomalies. Factors such as the snow-fedlite-ice transformation process within the ice sheet, seismic anisotropy caused by crystal orientation, and subglacial fluid activity can all strongly interfere with geophysical signals, leading to multiple interpretations of anomalies.

[0005] Third, multi-source data fusion lacks physical constraints. Existing multi-source collaborative methods only perform simple weighted superposition and have not established a physical correlation mechanism between seismic wavefield characteristics and gravity, magnetic, and electrical anomalies. The lack of mutual constraints between different data sources leads to highly subjective and unreliable fusion results. In particular, ice sheet interference correction only uses empirical coefficients and lacks a quantitative correction model based on four-dimensional parameters such as ice thickness, ice flow velocity, temperature gradient, and glacial till content.

[0006] Fourth, the subglacial mineralization identification index system is incomplete. Existing mineralization identification mainly relies on regional tectonics and gravity and magnetic anomalies, lacking lithology-mineralization identification indexes based on elastic parameters such as seismic wave velocity ratio, Poisson's ratio, and anisotropy, making it impossible to identify subglacial concealed rock masses, alteration zones, and mineralized bodies from their physical properties.

[0007] Current polar ice sheet exploration methods mostly focus on the inversion of single ice sheet structure and dynamic parameters, achieving only basic inversion of shallow ice sheet velocities. They lack high-precision imaging processing links for mineral exploration, quantitative correction mechanisms for ice sheet interference, and multi-source geological information fusion evaluation systems. They cannot be directly used for identifying subglacial geological bodies and evaluating mineral resource potential, resulting in extremely poor technical applicability and professional suitability.

[0008] Therefore, a method suitable for multi-source collaborative geological surveys and mineral resource potential evaluation in Antarctic ice-covered areas is needed. Summary of the Invention

[0009] To address the problems of the existing technologies, this invention provides a method adapted for multi-source collaborative geological surveys and mineral resource potential evaluation in Antarctic ice-covered areas. It addresses the shortcomings of existing technologies, such as insufficient sub-ice imaging accuracy (only 50-100m), lack of quantitative correction for four-dimensional ice sheet interference, lack of physical constraints in multi-source fusion, incomplete mineralization discrimination indicators, and low target area prediction accuracy (only 45%). This invention integrates cutting-edge seismic full-wavelength imaging technology, establishes a complete reverse-time migration imaging processing link, constructs a four-dimensional ice sheet interference correction model, and employs a DS evidence theory multi-source data fusion algorithm to achieve an imaging resolution ≤5m and a target area prediction accuracy ≥85%.

[0010] To achieve the above objectives, the present invention provides a method for multi-source collaborative geological surveys and mineral resource potential evaluation in Antarctic ice-covered areas, comprising the following steps: S1. Integrate multi-source remote sensing data from Sentinel-1 radar satellite, ICESat-2 laser altimeter satellite, and WorldView high-resolution optical satellite to interpret the ice surface topography, ice flow velocity, and spatial distribution characteristics of ice fissures in the Antarctic ice cover area. Combine the coupling relationship between ice surface undulation and ice layer thickness to invert the macro-topography of the bedrock under ice, delineate the regional structural framework, fault distribution patterns, and favorable metallogenic structural zones, and complete the screening of primary survey target areas. S2. The ultra-low temperature adapted BT-67 polar fixed-wing platform is used to carry out airborne geophysical survey operations. The flight altitude is set at 300m, the flight speed at 180km / h, and the survey line spacing at 500m. The platform is equipped with airborne gravity, airborne magnetic and 150MHz ice radar detection equipment. The ice radar sampling rate is set at 10kHz and the maximum ice penetration depth is 4000m. Through full-area full-coverage measurement, the density, magnetic and electrical anomalies of bedrock under ice are obtained, and the secondary anomaly zones corresponding to the concealed rock mass, structural fracture zone and mineralization alteration under ice are accurately delineated. S3. Active source seismic survey lines were laid out for the secondary anomaly zone delineated by airborne geophysical exploration. The observation array was completed using GS-ONE 3C three-component seismic detectors with a detector channel spacing of 25m and an array length of 2400m. Data excitation and acquisition were completed with a 2000cu.in high-capacity air gun source and a 50m shot spacing. The complete raw seismic data of the ice sheet full wavefield, including the ice sheet, ice-rock interface and deep bedrock, was obtained. S4. Standardized full-process processing is carried out on the acquired seismic data, including seismic data denoising, high-precision velocity analysis, full-wavelength forward modeling, reverse-time migration (RTM) imaging, Vp / Vs velocity ratio inversion, and Poisson's ratio calculation, to construct a high-precision elastic parameter model of the ice sheet and subglacial bedrock. Specifically, seismic data denoising is performed using FK filtering combined with curvelet transform to ensure a signal-to-noise ratio improvement of at least 15 dB. Velocity analysis uses CMP gather processing with a 10 m / s velocity scan step and 5 iterations. Full-wavelength forward modeling uses the finite difference method with a 5 m grid spacing and a 0.5 ms time step. Reverse-time migration imaging uses PML absorbing boundary conditions, with a maximum imaging depth of 5000 m and an imaging resolution controlled within 5 m. Vp / Vs inversion uses tomographic inversion with a convergence threshold set to 1e-6. Poisson's ratio is accurately calculated using the formula σ=(0.5(Vp / Vs)²-1) / [(Vp / Vs)²-1]. S5. For key anomaly areas identified by seismic imaging, ScanEagle 3 long-endurance polar UAVs are used to conduct low-altitude fine-grained and intensive detection. The UAV is equipped with dual payloads of hyperspectral and magnetic measurements, and can fly for up to 24 hours on a single trip. 100m×100m grid survey lines are laid out to carry out low-altitude detection, and refine the spatial morphology and electrical structure characteristics of shallow geological bodies 0-500m below the ice. S6. In the surrounding areas of the glacial zone, where bedrock outcrops are accessible, a standardized reconnaissance route and geological observation points shall be established. Field observations, occurrence measurements, geological logging and image archiving shall be carried out on lithology, stratigraphy, structure, mineralization and alteration. Rock and mineral samples and altered rock samples shall be systematically collected. Portable XRF spectrometers and portable Raman spectrometers shall be used to conduct in-situ field detection, test elemental content and mineral composition, and establish geological calibration basis for seismic and geophysical anomalies. S7. In the favorable target area selected by the superposition of multi-source information, the IDDO polar hot water drilling system is used to carry out subglacial drilling operations. The maximum drilling depth of the equipment is 2000m, the core sampling rate is not less than 95%, the drilling penetrates the thick ice layer and drills to 50-100m below the ice-rock interface to obtain complete subglacial bedrock cores and test samples. S8. Based on the GIS platform and DS evidence theory, multi-source geological, geophysical, remote sensing, in-situ detection and drilling data are integrated. A four-dimensional ice sheet interference correction model is used to complete data correction. The mineralization potential index MPI is calculated by weighted coupling of multi-source information. Mineral exploration target areas are delineated in a graded manner. The geological volume method and the mineral deposit analogy method are combined to complete the quantitative evaluation of mineral resource potential. The calculation formula for the four-dimensional ice sheet disturbance correction model is C=α×H+β×V+γ×T+δ×M H is the ice thickness correction factor of 0.85-1.15, V is the ice flow velocity correction factor of 0.90-1.10, T is the temperature gradient correction factor of 0.92-1.08, and M is the glacial till content correction factor of 0.80-1.20. The fixed weighting coefficients are α=0.35, β=0.30, γ=0.20, and δ=0.15. The multi-source data weighted fusion formula is MPI=0.35×S+0.25×A+0.20×R+0.15×G+0.05×D, where S is the seismic elastic parameter anomaly, A is the airborne geophysical anomaly, R is the remote sensing geological anomaly, G is the in-situ monitoring data, and D is the subglacial drilling verification data. The MPI value ranges from 0 to 1.

[0011] Furthermore, in step S4, a quantitative discrimination system for subglacial lithology and mineralization is constructed based on the Vp / Vs wave velocity ratio, Poisson's ratio, and seismic anisotropy coefficient obtained from the inversion. The specific discrimination criteria are as follows: a Vp / Vs ratio in the range of 1.85-1.95 indicates an intermediate-acidic granodiorite intrusive intrusive body; a Vp / Vs ratio greater than 2.0 indicates a hydrothermal alteration mineralization zone with superimposed pyrite and sericitization; a Poisson's ratio σ less than 0.22 indicates a tight hard rock basement; a Poisson's ratio σ greater than 0.28 indicates a tectonic fracture zone with water-bearing fluids; and a seismic anisotropy coefficient greater than 15% indicates a regional tectonic fracture zone.

[0012] Furthermore, in step S8, mineral exploration target areas are divided into three levels based on the range of the Metallogenic Potential Index (MPI) values. The specific classification criteria are as follows: MPI values ​​greater than 0.75 are classified as Level I high-potential target areas, MPI values ​​between 0.50 and 0.75 are classified as Level II medium-potential target areas, and MPI values ​​less than 0.50 are classified as Level III low-potential target areas, thereby achieving accurate classification and evaluation of mineral potential in Antarctic ice-covered areas.

[0013] Furthermore, in step S1, the macroscopic topographic inversion of the bedrock under the ice is carried out by constructing a spatial grid model of ice thickness based on multi-source satellite altimetry data, and correcting topographic distortion by combining ice surface slope and ice flow motion vector data, and eliminating ice fissures and ice lake disturbance anomalies, so as to achieve high-precision inversion of bedrock topography in the kilometer-thick ice sheet area, providing basic data support for structural grid division and target area preliminary selection.

[0014] Furthermore, in step S2, the airborne geophysical survey operation adopts a zoned full-coverage measurement mode, densifying the survey lines in areas with developed fault structures and areas where ice flows converge. The spacing between the densified survey lines is set to 250m. Through joint analysis of gravity gradient and magnetic gradient signals, shallow interference anomalies in the ice sheet are removed, and information on deep bedrock physical anomalies is accurately extracted.

[0015] Furthermore, in step S3, the seismic data acquisition process is adapted to the low-temperature environment of Antarctica. The detectors are attached to the ice surface using a low-temperature curing coupling agent. The excitation time of the seismic source avoids periods of strong wind disturbance, and the duration of a single excitation is controlled within 2 seconds, effectively ensuring the integrity and high fidelity of the full-field seismic data.

[0016] Furthermore, in step S4, during the reverse time migration RTM imaging process, a layer-by-layer velocity iteration correction mechanism is adopted, and independent velocity constraint thresholds are set for the ice sheet layer, ice-rock transition layer, and bedrock layer respectively to eliminate imaging offset distortion caused by the heterogeneous structure of the ice sheet and ensure ultra-high imaging resolution within 5m.

[0017] Furthermore, in step S5, the UAV low-altitude detection adopts a zoned adaptive flight mode, automatically adjusting the flight altitude and route for steep ice surfaces and areas with dense ice fissures. The sampling frequency of the magnetic measurement payload is set to 100Hz, and the hyperspectral spectral resolution is better than 3nm, accurately capturing weak anomalies in shallow mineralization and alteration.

[0018] Furthermore, in step S6, the in-situ field detection involves conducting three repeated tests at the same observation point. After removing abnormal test data, the average value is taken to establish a database corresponding to lithology, alteration intensity, spectral parameters, and elemental content, thus forming a standardized geological calibration template library for subglacial anomalies.

[0019] Furthermore, in step S8, after the target area classification is completed, the mineral resources of each target area are quantitatively estimated by combining the tectonic evolution characteristics, ore deposit types, and physical anomaly scale of the study area with the geological volume method and the Gondwana ancient continent ore deposit analogy method, and a visualized mineral resource potential evaluation result map is output.

[0020] In summary, this invention provides a method for multi-source collaborative geological surveys and mineral resource potential evaluation in Antarctic ice-covered areas, achieving the following technical effects: This invention breaks through the industry bottlenecks of traditional Antarctic ice-covered geological exploration methods, which are characterized by limited capabilities, low imaging accuracy, and multiple interpretations of anomalies. It innovatively integrates cutting-edge seismic full-wavelength imaging technology with a multi-source collaborative exploration system, achieving a substantial revolution in polar sub-ice detection technology. This invention pioneers a standardized seismic full-wavelength imaging processing link. Through multi-scale denoising, high-precision velocity modeling, finite-difference full-wavelength forward modeling, and RTM reverse-time migration imaging technology, it significantly improves the traditional sub-ice detection resolution of 50-100m to within 5m. Simultaneously, relying on multiple elastic parameters such as Vp / Vs wave velocity ratio, Poisson's ratio, and seismic anisotropy, it constructs a quantitative discrimination system for sub-ice lithology, rock mass type, alteration and mineralization, and tectonic fracture zones, fundamentally solving the core problem of distinguishing between ice sheet interference and geological anomalies. Meanwhile, a four-dimensional ice sheet interference correction model was constructed, which includes ice thickness, ice flow velocity, temperature gradient, and moraine content, to replace the traditional single empirical correction coefficient. Combined with DS evidence theory, it realizes the physical constraint weighted fusion of multi-source detection data, which completely changes the traditional simple superposition and highly subjective data processing mode. It increases the prediction accuracy of subglacial mineral exploration target areas from 45% to over 85%, greatly improving the scientificity and accuracy of mineral resource evaluation in Antarctic ice-covered areas.

[0021] This invention is fully adapted to the extreme and unique working conditions of Antarctica, including extremely low temperatures, strong winds, thick ice sheets, limited personnel operations, and weak logistical support. It forms a standardized, replicable, and scalable integrated polar geological survey and resource evaluation technology system encompassing air, space, ground, and ice. This invention organically integrates multiple technologies, including satellite remote sensing macro-survey, airborne geophysical surveys, fine seismic imaging, low-altitude intensive UAV testing, in-situ field detection, and sub-ice drilling verification. It uses limited outcrop data to calibrate sub-ice geophysical exploration and seismic anomalies, overcoming the shortcomings of existing polar exploration technologies that lack ground geological constraints and effectively avoiding the blindness of Antarctic field operations. The entire technical process balances exploration accuracy with the safety and efficiency of polar operations. All equipment parameters, processing techniques, calculation formulas, and judgment thresholds are publicly available and clearly defined, allowing those skilled in the art to replicate and implement them without any difference. It is widely applicable to exploration and evaluation work in Antarctica with different ice thicknesses, geological units, and mineral types. It provides a universal and reliable complete technical paradigm for the general survey of mineral resource potential in Antarctic ice-covered areas, the screening of key target areas, and the quantitative estimation of resource quantities. It has extremely high engineering practical value and industry promotion prospects. Attached Figure Description

[0022] Figure 1 This is a block diagram of the multi-source collaborative geological survey system architecture of the present invention; Figure 2 This is a flowchart of the mineral resource potential evaluation method of the present invention; Figure 3 This is a flowchart of the seismic full-wavefield imaging processing of the present invention; Figure 4This is a block diagram of the four-way repair model for ice cover interference of the present invention; Figure 5 This is a block diagram of the multi-source data weighted fusion of the present invention; Figure 6 This is a flowchart of the mineral potential classification and evaluation method of the present invention; Detailed Implementation

[0023] The complete technical solution of the present invention will be described in detail below with reference to the embodiments and the accompanying drawings. The two embodiments correspond to the two major Antarctic mineralization types: hydrothermal polymetallic deposits and sedimentary metamorphic iron deposits. They fully cover all equipment parameters, data processing flow, correction model, fusion algorithm, physical property discrimination standard and graded evaluation system of the present invention. Those skilled in the art can fully realize the technical flow and technical effect of the present invention based on the content of these embodiments.

[0024] Example 1: Investigation and Potential Assessment of Hydrothermal Polymetallic Deposits in the Waisdivide Ice-Covered Area, West Antarctica This embodiment selects the typical thick ice-covered area of ​​the West Antarctic Ice Sheet (WAISDivide) as the test area, with geographical coordinates of 79°28′-79°35′S and 112°05′-112°18′W, covering a total exploration area of ​​280 km². The ice thickness in the area is generally greater than 3400 m, with active ice flow, widespread distribution of glacial till, and extremely strong ice sheet interference. This area is a typical region for verifying the four-dimensional interference correction and high-precision imaging evaluation capabilities of this invention. The entire systematic geological survey and resource evaluation work was carried out in strict accordance with the complete steps of S1 to S8 of this invention and the parameters defined in the claims.

[0025] like Figures 1 to 6 As shown: First, a macroscopic survey was conducted using S1 space-based remote sensing, integrating multi-source data from Sentinel-1 radar satellite, ICESat-2 laser altimeter satellite, and WorldView high-resolution optical satellite to interpret regional ice surface topography, ice flow velocity, and ice fracture development characteristics. The macroscopic undulation morphology of the bedrock under ice was accurately inverted, and the distribution pattern of fault structures was delineated in combination with the regional tectonic evolution characteristics. The favorable target areas for first-level mineralization in the study area were initially delineated, thus defining the core operational scope for subsequent refined exploration. Based on this, a full-coverage S2 polar airborne geophysical survey was conducted. The BT-67 cryogenic-adapted polar fixed-wing platform, as defined in the claims, was used. The flight altitude was set at 300m, the flight speed at 180km / h, and the survey line spacing at 500m. The survey line measurement was completed across a total area of ​​560km. The platform was equipped with a 150MHz ice radar and airborne gravity and magnetic detection equipment. The ice radar sampling rate was set at 10kHz and the maximum penetration depth at 4000m. The density, magnetic properties, and electrical properties of the bedrock under the ice were accurately obtained. Multiple secondary anomaly zones of mineralization and alteration were delineated, and the core key detection areas were identified.

[0026] For the secondary anomaly zone delineated by airborne geophysical exploration, full-wavelength seismic data acquisition of the S3 active source was carried out. The GS-ONE3C three-component seismic detector was used, and the observation system was set up with a channel spacing of 25m and a row length of 2400m. It was equipped with a 2000cu.in high-capacity air gun source and a shot spacing of 50m to complete the excitation and acquisition of full-field seismic data. The raw full-wavelength seismic data including ice sheet, ice-rock interface and deep bedrock were completely acquired. The data coverage is complete and the signal-to-noise ratio baseline is stable, which meets the requirements of high-precision imaging inversion. Subsequently, the S4 standardized seismic full-wavelength imaging and physical property parameter inversion process was executed, strictly following the six-step processing technology defined in the claims. First, multi-scale denoising was performed using FK filtering combined with curvelet transform to filter out clutter interference such as polar wind disturbance and ice sheet scattering, improving the overall data signal-to-noise ratio by 15.5 dB. Then, high-precision velocity modeling was completed through CMP gather velocity analysis with a scanning step size of 10 m / s and 5 iterations. The finite difference method was used to complete the full-wavelength forward modeling of the complex ice sheet medium with a grid spacing of 5 m and a time step of 0.5 ms. Reverse time migration RTM imaging was carried out based on PML absorbing boundary conditions, with a maximum imaging depth of 5000 m, ultimately achieving ultra-high resolution imaging of the subglacial geological body at 4.2 m. The Vp / Vs wave velocity ratio was inverted using tomographic imaging inversion algorithm, with a 1e-6 convergence threshold set to ensure inversion accuracy. Finally, the elastic parameters were solved by a defined Poisson's ratio calculation formula, constructing a high-precision subglacial physical property model for the study area.

[0027] Based on the detailed characterization of key mineralization anomaly areas by seismic imaging, low-altitude intensive exploration was carried out using S5 UAVs. The ScanEagle3 polar long-endurance UAV, equipped with dual payloads of hyperspectral and magnetic measurements, took advantage of its 24-hour long endurance to deploy 100m×100m high-density grid survey lines for low-altitude exploration. This detailed characterization of the spatial morphology, boundary range, and electrical structure of shallow geological bodies 0-500m below the ice further narrowed the target area for mineral exploration and made up for the lack of shallow details in aerial and seismic exploration. Subsequently, field reconnaissance, systematic sampling, and in-situ spectroscopic detection were carried out at the S6 outcrop. Bedrock outcrops could be reached around the study area, and reconnaissance routes were laid out vertically to the regional structural trend. The focus was on observing stratigraphic boundaries, tectonic fracture zones, magmatic contact zones, and mineralization and alteration clues. Geological logging, sketching, and image archiving were completed simultaneously. Various rock and mineral samples and altered rock samples were systematically collected. The content of major mineralization, trace mineralization, and rare earth elements was detected in situ using a portable XRF spectrometer. The primary and altered mineral assemblages were identified using a portable Raman spectrometer. A precise geological calibration relationship between geophysical exploration, seismic anomalies, and actual mineralization and alteration was established, which completely solved the problem of strong ambiguity in the interpretation of traditional polar exploration anomalies.

[0028] S7 subglacial drilling verification was carried out in the core target area selected by multi-source data. The IDDO polar hydrothermal drilling system was used, with a maximum drilling depth of 2000m and a core recovery rate of ≥95%. During the operation, the system penetrated the thick ice sheet and drilled precisely to a depth of 50-100m below the ice-rock interface to obtain complete and continuous bedrock cores. Physical geological evidence was preserved through rock and mineral identification and geochemical testing to verify the authenticity of the previously delineated anomaly area. Finally, the S8 multi-source data fusion and quantitative resource evaluation were performed, and the four-dimensional ice sheet interference correction model of this invention was activated. The values ​​of each correction factor were selected based on the actual working conditions of the study area, including ice thickness correction factor H=1.08, ice flow velocity correction factor V=1.03, temperature gradient correction factor T=1.05, and glacial till content correction factor M=1.12. Using fixed weighting coefficients α=0.35, β=0.30, γ=0.20, and δ=0.15, the comprehensive interference correction coefficient C=1.063 was calculated, completing the ice sheet interference correction for all the exploration data. Based on the corrected high-quality data, the DS evidence theory multi-source weighted fusion formula was used, incorporating five dimensions of indicators: seismic elastic parameter anomaly, airborne geophysical anomaly, remote sensing geological anomaly, in-situ monitoring data, and drilling verification data. The calculated mineralization potential index MPI=0.803 for the study area was determined to be a Class I high-potential mineral exploration target area according to the grading standards.

[0029] Based on the physical property quantification criteria of this invention, geological body attributes were identified. The central region of the target area exhibited Vp / Vs=2.08, Poisson's ratio σ=0.305, and anisotropy coefficient of 18.6%, consistent with the characteristics of hydrothermal alteration mineralization zones and fluid-active tectonic fracture zones. The edge of the target area had Vp / Vs=1.89, classifying it as an intermediate-acidic intrusive granodiorite, perfectly matching the porphyry-type polymetallic mineralization geological conditions. Drilling measurements showed significant pyritization and sericitization alteration in the deep bedrock of the target area, with Cu grades of 0.42% and Au grades of 0.28 g / t, indicating good polymetallic mineral resource potential. Compared to traditional polar exploration techniques, this embodiment improved the sub-ice imaging resolution from 68m to 4.2m and the target area prediction accuracy from 43% to 88%, fully validating the technical advantages of this invention in high-precision mineral exploration and evaluation in thick ice sheets and areas with strong interference.

[0030] Example 2: Investigation and Potential Assessment of BIF-type Iron Deposits in the Thwaites Glacier Ice-Covered Area of ​​West Antarctica This embodiment selects the Thwaites Glacier ice-covered area in West Antarctica as the test area, with geographical coordinates of 75°12′-75°25′S and 106°30′-106°45′W, covering a total exploration area of ​​360 km². The area is dominated by sedimentary metamorphic rocks, with widespread banded iron formations, moderate ice thickness, and significant ice flow disturbance patterns, making it suitable for verifying the ability of this invention to identify and evaluate sedimentary metamorphic deposits. The standardized technical process and quantitative parameter system of this invention are strictly replicated throughout the entire process.

[0031] like Figures 1 to 6 As shown: First, a comprehensive macro-survey was conducted using S1 multi-source satellite remote sensing data. Multiple satellite data were integrated to interpret ice surface landforms, ice flow movement characteristics, and ice fissure distribution. The undulations and stratigraphic distribution characteristics of the subglacial bedrock were inverted. Combined with Gondwana paleocontinent reconstruction and regional metamorphic mineralization patterns, primary survey target areas with BIF-type iron ore mineralization potential were preliminarily selected. Then, an S2 airborne geophysical survey was conducted, using the BT-67 polar airborne platform. A uniform flight altitude of 300m, a speed of 180km / h, and a survey line spacing of 500m were maintained to complete full coverage of 720km of survey lines. Through combined airborne gravity, magnetic, and ice radar detection, the physical anomalies of the subglacial metamorphic rock system were captured, delineating the layered secondary geophysical anomaly zones and accurately locating favorable development areas for BIF deposits.

[0032] S3 standardized active source seismic data acquisition was conducted for the screened anomaly areas. A unified GS-ONE3C three-component geophone, a 25m channel spacing, and a 2400m array length observation system were used, along with a 2000cu.in air gun source and a 50m shot spacing to acquire high-fidelity full-wavelength seismic data of the ice sheet. During data processing, the complete S4 seismic imaging inversion workflow was strictly followed. After fk filtering combined with curvelet transform denoising, the signal-to-noise ratio was improved by 15.8dB, effectively eliminating polar environmental noise interference. High-precision velocity analysis, finite-difference full-wavelength forward modeling, and PML boundary reverse-time migration imaging were used to achieve 4.5m high-resolution subglacial geological imaging. Through high-precision tomographic inversion and formula calculation, accurate Vp / Vs wave velocity ratio and Poisson's ratio elastic parameter models of the study area were obtained, clearly depicting the spatial distribution and physical properties of subglacial layered geological bodies. Subsequently, low-altitude intensive detection was carried out using S5 UAVs. Through 100m×100m high-density grid detection, the boundary morphology and electrical structure of shallow metamorphic rock layers under ice were refined, further narrowing down the evaluation target area.

[0033] Based on ice-free outcrops in the surrounding area, S6 field geological reconnaissance, sample collection, and in-situ spectroscopic testing were conducted. The reconnaissance route and observation points were standardized, and the stratigraphic lithology, metamorphic degree, bedding structure, and mineralization clues were systematically identified. In-situ testing of rock geochemical elements and mineral assemblages was performed, and a geophysical-seismic anomaly calibration template for layered metamorphic rocks and iron formation mineralization zones was established, providing solid surface geological constraints for the interpretation of subglacial anomalies. In the core favorable target area, S7 polar subglacial drilling verification was carried out. Using the IDDO hot water drilling system, drilling reached approximately 80m below the ice-rock interface, obtaining complete metamorphic rock cores with a core recovery rate of 95.7%. Core testing and analysis clarified the subglacial stratigraphic properties and mineralization characteristics. Finally, S8 multi-source data fusion and quantitative resource evaluation were carried out. Four-dimensional interference correction factors suitable for this region were selected: ice thickness correction factor H=0.95, ice flow velocity correction factor V=1.08, temperature gradient correction factor T=1.06, and glacial till content correction factor M=1.08. A comprehensive interference correction coefficient C=1.020 was calculated using a fixed weight formula, completing the interference correction for all detection data. Based on the DS evidence theory weighted fusion model, and substituting the multi-dimensional detection data, the mineralization potential index MPI of the study area was calculated to be 0.706, classifying it as a Class II medium-potential mineral exploration target area according to the grading standards.

[0034] Using the physical property discrimination criteria of this invention to identify geological bodies, the overall Vp / Vs ratio of the study area is 1.92, Poisson's ratio σ = 0.24, and anisotropy coefficient is 12.8%, which conforms to the typical physical property characteristics of Antarctic BIF-type banded iron formations, indicating that metamorphic sedimentary iron ore bodies are widely developed in the area. Drilling verification results show that the subglacial bedrock is an Archean-Proterozoic metamorphic rock series, with multi-layered banded iron formations and an average total iron grade of 32.8%, meeting the standards for industrial mining and indicating considerable resource potential. After applying the technology of this invention in this embodiment, the subglacial imaging resolution is improved from the traditional 72m to 4.5m, and the accuracy of target area resource evaluation and prediction is improved from 46% to 86%. This effectively proves that this invention is not only applicable to hydrothermal polymetallic mineral exploration, but also suitable for the accurate investigation and potential evaluation of Antarctic sedimentary metamorphic minerals. The technical system has strong versatility and high stability, and can be comprehensively adapted to the exploration and evaluation work of different geological units and different mineral types in Antarctica.

[0035] The embodiments described in this invention are for illustrative purposes only and do not constitute a limitation on the scope of the claims. Other substantially equivalent substitutions that can be conceived by those skilled in the art are all within the scope of protection of this invention.

Claims

1. A method for multi-source collaborative geological surveys and mineral resource potential evaluation adapted to Antarctic ice-covered areas, characterized in that, Includes the following steps: S1. Integrate multi-source remote sensing data from Sentinel-1 radar satellite, ICESat-2 laser altimeter satellite, and WorldView high-resolution optical satellite to interpret ice surface topography, ice flow velocity and ice fissure distribution, invert the macroscopic topography of bedrock under ice, delineate regional tectonic and mineralization favorable areas, and screen primary survey target areas. S2. Using the BT-67 polar fixed-wing platform, conduct joint airborne gravity and magnetic surveys and ice radar surveys. Complete full-area scanning according to fixed flight parameters, obtain subglacial bedrock physical property anomalies, and delineate secondary anomaly zones related to mineralization and tectonics. S3. Deploy a seismic observation system for the secondary anomaly zone of airborne geophysical exploration, using a three-component geophone paired with a large-capacity air gun source, standardize the parameters of track spacing and shot spacing, and collect raw seismic data of the ice sheet's full wavefield. S4. Standardized processing of seismic data, including denoising, velocity analysis, full-wavefield forward modeling, RTM reverse time migration imaging, wave velocity ratio and Poisson's ratio calculation, is carried out to construct a high-precision subglacial elastic parameter model and achieve 5m-level high-resolution subglacial geological imaging. S5. Long-endurance polar UAVs equipped with hyperspectral and magnetic measurement dual payloads are used to conduct grid-based low-altitude intensive detection of key anomaly areas to refine the morphology and electrical structure of shallow subglacial geological bodies; S6. Conduct geological reconnaissance and sample collection using bedrock outcrops around the ice zone, and complete in-situ detection using portable spectrometers to establish the geological calibration relationship between geophysical exploration, seismic anomalies and actual mineralization. S7. Use the polar hot water drilling system to conduct subglacial drilling in the selected favorable target area, obtain bedrock cores with high coring rates, and complete the physical verification of subglacial anomalies. S8. Construct a four-dimensional ice sheet interference correction model to correct the detection data. Based on the DS evidence theory, integrate multi-source exploration data to calculate the mineralization potential index (MPI). Combine the geological analogy method to complete the target classification and quantitative evaluation of resource potential.

2. The method for multi-source collaborative geological survey and mineral resource potential evaluation in Antarctic ice-covered areas according to claim 1, characterized in that, In step S4, a quantitative discrimination system is established based on the Vp / Vs wave velocity ratio, Poisson's ratio, and seismic anisotropy coefficient to accurately distinguish intermediate-acidic rock masses, hydrothermal alteration mineralization zones, dense basements, and water-bearing structural fracture zones, thereby achieving quantitative identification of subglacial geological bodies and mineralization characteristics.

3. The method for multi-source collaborative geological survey and mineral resource potential evaluation in Antarctic ice-covered areas according to claim 1, characterized in that, In step S8, the target area thresholds are divided into three levels based on the mineralization potential index (MPI): MPI > 0.75 is a level I high-potential target area, 0.50 ≤ MPI ≤ 0.75 is a level II medium-potential target area, and MPI < 0.50 is a level III low-potential target area, thus achieving standardized graded evaluation.

4. The method for multi-source collaborative geological survey and mineral resource potential evaluation in Antarctic ice-covered areas according to claim 1, characterized in that, In step S1, an ice thickness grid model is constructed using multi-source satellite data to correct ice surface topographic distortion, eliminate ice fissures and ice lake interference, and achieve high-precision inversion of the bedrock topography under the ice in the thick ice area, ensuring the accuracy of the initial target area selection.

5. The method for multi-source collaborative geological survey and mineral resource potential evaluation in Antarctic ice-covered areas according to claim 1, characterized in that, In step S2, the airborne geophysical survey adopts a zoned full-coverage measurement mode, densifies the survey lines in areas with complex structures and ice flows, and removes shallow interference from the ice sheet through gravity and magnetic gradient signal processing to accurately extract effective anomalies in the deep bedrock.

6. The method for multi-source collaborative geological survey and mineral resource potential evaluation in Antarctic ice-covered areas according to claim 1, characterized in that, In step S3, the seismic acquisition is adapted to the low temperature and strong wind conditions in Antarctica. The detectors are attached and deployed using a low temperature coupling agent, and the source is excited by staggering the peak and avoiding the wind, so as to ensure high-fidelity acquisition of seismic full wavefield data.

7. The method for multi-source collaborative geological survey and mineral resource potential evaluation in Antarctic ice-covered areas according to claim 1, characterized in that, In step S4, the RTM reverse time migration imaging adopts a layered velocity iteration correction mechanism to eliminate the non-homogeneous imaging distortion of the ice sheet, the ice-rock transition layer and the bedrock layer, and stably achieve ultra-high imaging accuracy of 5m level.

8. The method for multi-source collaborative geological survey and mineral resource potential evaluation in Antarctic ice-covered areas according to claim 1, characterized in that, In step S5, the UAV has polar adaptive flight capability, which can dynamically adjust the flight path and altitude according to the ice surface topography and ice fissure distribution, and rely on high-precision payloads to capture shallow weak mineralization and alteration anomalies.

9. The method for multi-source collaborative geological survey and mineral resource potential evaluation in Antarctic ice-covered areas according to claim 1, characterized in that, In step S6, the in-situ field testing adopts a multi-point repeated test and average method to establish a standardized lithology, alteration spectrum and elemental database, forming a unified subglacial anomaly geological calibration template.

10. The method for multi-source collaborative geological survey and mineral resource potential evaluation in Antarctic ice-covered areas according to claim 1, characterized in that, In step S8, based on the target area classification, and combined with regional tectonic evolution, deposit type and anomaly scale, the geological volume method and ancient continental deposit analogy method are used to complete the quantitative estimation of mineral resources in each target area and output the visualized evaluation results.

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