A method for accurately positioning and detecting a lithium ore granite pegmatite vein ore body

Abstract

The application discloses a lithium ore granite pegmatite vein ore body precise positioning detection method and relates to the technical field of mineral resources exploration. The method circumscribes a first target area through regionalized exploration, then arranges a comprehensive detection profile in the target area, uses the spatial superposition constraint of four methods of high-density resistivity, time-domain induced polarization, ground gamma energy spectrum and portable X-ray fluorescence spectrum to exclude false anomalies of carbonaceous slate and feldspar veins, determines a continuous section meeting multi-condition coupling as a precise positioning target area, further generates a three-dimensional resistivity body and a polarization rate body based on multi-profile inversion data, extracts a resistivity equipotential surface to predict the spatial distribution of the pegmatite vein body, and designs a verification borehole. In the drilling verification link, a local natural mineral base material is compounded with an environment-friendly mud, layered adaptive drilling is adopted, drill cuttings-mud in-situ aerobic composting is carried out, and the composting products are backfilled and repaired in cooperation with local dominant plant seeds, so that rapid ecological restoration is realized.

Description

Technical Field

[0001] This invention relates to the field of mineral resource exploration technology, specifically a method for precise location and detection of lithium granite pegmatite vein ore bodies. Background Technology

[0002] Granite pegmatite-type lithium deposits are one of the key types of lithium resource exploration currently. These deposits often occur as narrow veins with steep dips, typically 2-10 meters wide and with dips generally greater than 70°. Furthermore, they exhibit relatively small differences in resistivity, density, and magnetic properties compared to the surrounding rocks (such as metamorphic sandstone, slate, and granite). Traditional single geophysical exploration methods (such as high-density resistivity methods, induced polarization methods, and magnetic methods) face the following challenges when dealing with these types of deposits: Insufficient positioning accuracy and limited vertical resolution of conventional resistivity methods for steeply dipping thin veins result in inverted depth errors of 10-20m for the top and bottom plates of the ore body, which is difficult to meet the requirements of refined exploration and leads to a high miss rate during borehole verification. False anomalies cause significant interference. Carbonaceous slate and pyrite-mineralized host rocks often produce false anomalies with high polarizability (polarizability > 6%), while feldspar veins produce false anomalies with high potassium radioactivity. Traditional methods are unable to effectively distinguish between ore-bearing pegmatites and ore-free geological bodies, and the success rate of drilling verification is generally less than 40%. Drilling processes cause serious environmental pollution. Existing drilling projects mostly use chemically synthesized drilling mud (containing polyacrylamide, alkalis and other difficult-to-degrade components), and the cost of transporting and disposing of drill cuttings is high. In high-altitude and cold mountainous areas and nature reserves, it can easily cause long-term soil and water pollution.

[0003] Therefore, there is an urgent need to develop a comprehensive detection method that can accurately locate lithium granite pegmatite veins and achieve environmentally friendly drilling and ecological restoration. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a precise location detection method for lithium granite pegmatite veins. This method delineates the primary target area through regional geochemical exploration, then deploys comprehensive detection profiles within the target area. It utilizes the spatial superposition constraints of four methods—high-density resistivity, time-domain excited polarizability, ground gamma ray spectroscopy, and portable X-ray fluorescence spectroscopy—to eliminate false anomalies in carbonaceous slate and feldspar veins. Continuous sections satisfying multi-condition coupling are identified as the precise location target area. Furthermore, based on multi-profile inversion data, three-dimensional resistivity and polarizability volumes are generated. Resistivity isosurfaces are extracted to predict the spatial distribution of the pegmatite veins, and verification boreholes are designed. In the drilling verification stage, local natural mineral matrix is ​​used to formulate environmentally friendly drilling mud, employing layered adaptive drilling and in-situ aerobic composting of drill cuttings and mud. The composted products are then backfilled with local dominant plant seeds for rapid ecological restoration. This method is suitable for lithium exploration in ecologically fragile areas such as high-altitude mountainous regions, permafrost zones, and nature reserves.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for accurately locating and detecting lithium granite pegmatite vein ore bodies, the specific steps of which are as follows: S100, based on water system sediment measurements and soil geochemical measurements, delineated the lithium element anomaly zone as a primary target area; S200. Within the primary target area, deploy comprehensive detection profiles with a profile spacing of 100-200m and a point spacing of 10-20m. On each profile, sequentially collect high-density resistivity data, time-domain excited polarizability data, ground-based gamma-ray energy spectrum data, and portable X-ray fluorescence spectrum data. Data must simultaneously meet the following criteria: resistivity 300-1500 Ω·m, polarizability 1.5%-5.5%, potassium / thorium ratio 1.5-3.0, and rubidium + cesium content ≥200 × 10⁻⁶. -6 The continuous segment was determined as the precise positioning target area; S300. Import the resistivity inversion data and polarizability inversion data of all integrated detection profiles into the three-dimensional visualization platform to generate a three-dimensional resistivity volume and a three-dimensional polarizability volume. Extract the resistivity isosurfaces 500Ω·m and 1200Ω·m from the three-dimensional resistivity volume. Determine the spatial region between the two isosurfaces as the predicted pegmatite vein. Design and verify the borehole based on the occurrence of the predicted pegmatite vein. S400. The verification borehole is drilled and verified using a hydraulic drilling rig. The drilling and verification process includes the following steps: screening and pretreatment of local natural mineral matrix, on-site preparation of compounded environmentally friendly mud, layered adaptive drilling, core logging and rapid grade analysis, in-situ co-composting of drill cuttings and mud, and co-remediation of composted products and local vegetation. S500: Feedback the actual occurrence, thickness and grade of the ore body revealed by S400 drilling to the three-dimensional resistivity volume and three-dimensional polarizability volume generated by S300 for comparison and correction, and correct the quantitative relationship between resistivity and lithium grade. S600. Based on the chemical analysis results of all verification boreholes, estimate the lithium resource quantity using the geological block method or the Kriging method, and delineate the three-dimensional boundary of the oreable body.

[0006] Furthermore, in S200, the high-density resistivity data is obtained by measuring the high-density resistivity method. The high-density resistivity method measurement uses a Winner device or a Schlumberger device, and the maximum electrode distance AB / 2 is 500m. The time-domain induced polarizability data were obtained by measuring the time-domain induced polarizability method. The time-domain induced polarizability method measurement was performed synchronously with the high-density resistivity method measurement. The power supply time was 2 seconds and the delay time was 150 ms. Ground-based gamma-ray spectrometer data were obtained using a portable gamma-ray spectrometer, with a single-point measurement time of 120 seconds. Portable X-ray fluorescence spectroscopy data were obtained using a handheld X-ray fluorescence spectrometer, with a single-point measurement time of 60 seconds.

[0007] Furthermore, in step S400, the screening and pretreatment steps of the local natural mineral matrix are as follows: Claystone or weathered layer samples were collected within a 20km radius of the planned borehole, and the montmorillonite content in the samples was detected using a portable X-ray diffractometer. Natural kaolin or natural montmorillonite with a montmorillonite content ≥60%, an expansion factor ≥8 times, and a heavy metal content below the preset limit was selected as the natural mud base material. The selected natural mud base material is crushed at the construction site and passed through a 200-mesh sieve to obtain pretreated natural mud base material.

[0008] Furthermore, in step S400, the on-site preparation step of the compounded environmentally friendly mud slurry is as follows: The pretreated natural mud base, biodegradable thickener and bio-based wall protector were added to a mobile mud mixing device at a mass ratio of 80:15:5 for in-situ compounding. The biodegradable thickener is sodium carboxymethyl cellulose, and the bio-based wall-protecting agent is plant gum or modified starch; The mixing speed is 800-1200 r / min, and the mixing time is ≥20 min to obtain a compound environmentally friendly slurry; The performance indicators of the compounded environmentally friendly mud are controlled as follows: density 1.02-1.08 g / cm³, funnel viscosity 25-35 s, and water loss ≤12 mL / 30 min.

[0009] Furthermore, in S400, the step of layered adaptive drilling is as follows: Based on the lithology of the strata, the vertical depth of the borehole is divided into three sections, and different drilling parameters are used for each section. The first layer is the surface layer, with a depth range of 0-5m. The surface layer includes meadow soil or loose deposits on scree slopes. The surface layer uses a low rotation speed of 150-200 r / min, a low pump flow rate of 30-40 L / min, and a mud viscosity of 33-35s. The second section is the middle section, with a depth range of 5m to 10m above the predicted top plate of the ore body. The middle section includes metamorphic sandstone, slate or granite. The middle section uses a medium rotation speed of 300-400r / min, a medium pump flow rate of 50-70L / min, and a mud viscosity of 30-32s. The third section is the mineralization section, which is the section after entering the spodumene pegmatite vein. In this section, the mud water loss is reduced to ≤10mL / 30min, the rotation speed is reduced to 200-250r / min, the pump flow rate is maintained at 50L / min, and the mechanical drilling rate is controlled at 0.5-1.0m / h. During the drilling process, the amount of mud consumed, the color of the returned water, and the characteristics of the core were recorded after each drilling operation. When spodumene appeared in the core, the mud properties were adjusted and the mechanical drilling speed was reduced.

[0010] Furthermore, in S400, the steps for core logging and rapid grade analysis are as follows: After each core sample is retrieved, the core samples are cleaned, sorted, and numbered, and a core tag is filled out. Observe and record the lithological, mineralization, and alteration characteristics layer by layer; Semi-quantitative rapid analysis of lithium content in the core section was performed using a handheld laser-induced breakdown spectrometer or a portable X-ray fluorescence spectrometer, with measurements taken at a point every 0.5m, and the boundary line of the industrial ore body was delineated on site. The core section was cut in half. One half was sent to the laboratory as a test sample for chemical analysis, while the other half was preserved as a specimen in the core bank.

[0011] Furthermore, in step S400, the in-situ co-maturation step of drill cuttings and drilling mud is as follows: An impermeable composting tank is set up near the borehole, and the bottom of the impermeable composting tank is covered with geotextile and a 10cm thick layer of sand and gravel. Drill cuttings discharged during drilling are mixed with residual drilling mud at a volume ratio of 3:1, and a compound microbial agent is added to obtain a mixture. The compound microbial agent contains Bacillus subtilis, Pseudomonas, and yeast, and the total viable count of the compound microbial agent is ≥1×10⁻⁶. 8 CFU / g, the amount of compound microbial agent added is 2kg of agent per cubic meter of the mixture; The mixture is subjected to aerobic fermentation in the seepage-proof composting tank. During the fermentation period, the mixture is turned over every 3 days, and the fermentation cycle is 15-30 days. When the local temperature is below 10℃, cover with black insulating film and extend the fermentation period to 40 days; The criteria for determining the fermentation endpoint are: the material has no odor, the material temperature drops to ambient temperature, the material pH value is 6.5-7.5, and the material organic matter content is ≥8%.

[0012] Furthermore, in step S400, the step of co-remediation of decomposed products and native vegetation is as follows: After all drilling work is completed, the decomposed product is directly backfilled into the disturbed area around the borehole. The disturbed area around the borehole includes the machine platform leveling area, mud pit and construction access road. The backfilling and spreading thickness of the decomposed product is 10-15cm. Seeds of native dominant plants were collected within 500m of the disturbance area around the borehole. For areas above 3500m altitude, the native dominant plant seeds were selected from Kobresia alpinea, Leymus chinensis, and Poa lanceolata. For areas below 3500m altitude or arid areas, the native dominant plant seeds were selected from Tamarix chinensis and Hippophae rhamnoides. The native dominant plant seeds were mixed with the surface of the decomposed product at a sowing rate of 15-20g / ㎡. During the seed germination period, a photovoltaic water pump is used to draw stream water for drip irrigation and maintenance. The drip irrigation and maintenance is carried out once every 2 days, and the surface layer is moistened by 10cm each time. The drip irrigation and maintenance lasts for 2 months. After the maintenance period, the vegetation coverage rate should be calculated, and the vegetation coverage rate should be ≥70%.

[0013] Furthermore, in S500, the comparison correction includes: If the actual ore thickness or the actual ore grade of the verification borehole is less than 70% of the predicted value, then an additional densification borehole shall be added within a 50m radius around the original verification borehole. If the actual mineralization of the verification borehole is greater than the predicted value, then the next verification borehole is laid out 100m outward along the predicted pegmatite vein.

[0014] Furthermore, in S300, the three-dimensional resistivity volume and the three-dimensional polarizability volume are constructed using the Kriging interpolation method; When extracting the resistivity isosurfaces 500 Ω·m and 1200 Ω·m from the three-dimensional resistivity volume, the area with resistivity below 500 Ω·m is defined as the surrounding rock area. Regions with resistivity higher than 1200 Ω·m are defined as quartz veins or void regions. The region with resistivity between 500 Ω·m and 1200 Ω·m was identified as the predicted area for ore-bearing pegmatite veins.

[0015] Compared with existing technologies, this method for precise location detection of lithium granite pegmatite vein ore bodies has the following advantages: This invention constructs a green and low-carbon drilling and ecological restoration process in S400, which includes screening and pretreatment of local natural mineral matrix materials, on-site preparation of compounded environmentally friendly mud, layered adaptive drilling, in-situ co-composting of drill cuttings and mud, and co-remediation of composted products with local vegetation. By using natural kaolin or montmorillonite mines within a 20km radius of the borehole as mud matrix materials to replace the chemical bentonite transported over long distances, and combining a lightweight portable hydraulic drilling rig powered by photovoltaic panels and lithium battery packs, the carbon emissions of the entire process are significantly reduced compared to the traditional diesel engine plus long-distance transportation mode. At the same time, drill cuttings and residual mud are converted into ecological restoration matrix with an organic matter content of ≥8% after aerobic fermentation with compound microbial agents. This matrix is ​​directly backfilled into the disturbed area and drip-irrigated with local dominant plant seeds. There is no solid waste transportation and no chemical residues. It is suitable for lithium exploration in high-altitude ecologically fragile areas and nature reserves.

[0016] This invention delineates the primary target area through regional geochemical exploration, then deploys comprehensive exploration profiles within the target area. Utilizing the spatial superposition constraints of four methods—high-density resistivity, time-domain excited polarizability, ground-based gamma ray spectroscopy, and portable X-ray fluorescence spectroscopy—false anomalies in carbonaceous slate and feldspar veins are eliminated. Continuous sections satisfying multi-condition coupling are identified as precisely located target areas. Furthermore, based on multi-profile inversion data, three-dimensional resistivity and polarizability volumes are generated. Resistivity isosurfaces are extracted to predict the spatial distribution of pegmatite veins, and verification boreholes are designed. During the drilling verification phase, local natural mineral-based environmentally friendly drilling mud is used, along with layered adaptive drilling and in-situ aerobic composting of drill cuttings and mud. The composted products are then synergistically backfilled with local dominant plant seeds for restoration, achieving rapid ecological recovery.

[0017] Other advantages, objectives and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be learned from the 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 accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0019] Figure 1 This is a flowchart of a method for accurately locating and detecting lithium granite pegmatite vein ore bodies according to an embodiment of the present invention; Figure 2 This is a flowchart illustrating the drilling verification process in an embodiment of the present invention. Detailed Implementation

[0020] To better understand the above technical solutions, a detailed description of the solutions will be provided below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0021] This embodiment takes a lithium mine granite pegmatite vein exploration project in a high-altitude cold mountainous area as an example to provide a detailed description of a precise location detection method for lithium mine granite pegmatite vein ore bodies provided by the present invention. The working area has an altitude range of 3600m-4200m, belongs to a deeply dissected high mountain canyon area, has an average annual temperature of 3.2℃, an annual precipitation of 780mm, and vegetation is mainly alpine meadow. The target mineral is spodumene-type granite pegmatite vein, with the vein trending northeast, a dip angle of 75°-85°, and a vein width of 2m-8m.

[0022] To address the problems of large location errors (10-20m) in conventional geophysical exploration methods for steeply dipping thin-vein lithium orebodies, difficulty in eliminating false anomalies with high polarization caused by carbonaceous slate and feldspar veins, long-term soil and water pollution in ecologically fragile high-altitude areas caused by traditional chemical drilling, and long natural vegetation recovery cycles after drilling disturbance, this invention provides a precise location and detection method for lithium granite pegmatite vein orebodies. Figure 1 As shown, Figure 1 This is a flowchart of a method for precise location and detection of lithium granite pegmatite vein ore bodies according to an embodiment of the present invention. The steps of the method include: S100, based on water system sediment measurements and soil geochemical measurements, delineated the lithium element anomaly zone as a primary target area; S200. Within the primary target area, deploy comprehensive detection profiles with a profile spacing of 100-200m and a point spacing of 10-20m. On each profile, sequentially collect high-density resistivity data, time-domain excited polarizability data, ground-based gamma-ray energy spectrum data, and portable X-ray fluorescence spectrum data. Data must simultaneously meet the following criteria: resistivity 300-1500 Ω·m, polarizability 1.5%-5.5%, potassium / thorium ratio 1.5-3.0, and rubidium + cesium content ≥200 × 10⁻⁶. -6 The continuous segment was determined as the precise positioning target area; S300. Import the resistivity inversion data and polarizability inversion data of all integrated detection profiles into the three-dimensional visualization platform to generate a three-dimensional resistivity volume and a three-dimensional polarizability volume. Extract the resistivity isosurfaces 500Ω·m and 1200Ω·m from the three-dimensional resistivity volume. Determine the spatial region between the two isosurfaces as the predicted pegmatite vein. Design and verify the borehole based on the occurrence of the predicted pegmatite vein. S400. The verification borehole is drilled and verified using a hydraulic drilling rig. The drilling and verification process includes the following steps: screening and pretreatment of local natural mineral matrix, on-site preparation of compounded environmentally friendly mud, layered adaptive drilling, core logging and rapid grade analysis, in-situ co-composting of drill cuttings and mud, and co-remediation of composted products and local vegetation. S500: Feedback the actual occurrence, thickness and grade of the ore body revealed by S400 drilling to the three-dimensional resistivity volume and three-dimensional polarizability volume generated by S300 for comparison and correction, and correct the quantitative relationship between resistivity and lithium grade. S600. Based on the chemical analysis results of all verification boreholes, estimate the lithium resource quantity using the geological block method or the Kriging method, and delineate the three-dimensional boundary of the oreable body.

[0023] In a preferred embodiment, step S100 first collects existing regional geological, mineral, geochemical, and remote sensing interpretation data of the exploration area and its surroundings, and collects 1:50,000 stream sediment measurement data of the work area, with the lower limit of lithium anomaly being 80 × 10⁻⁶. -6 Based on this data, three lithium anomaly concentration centers were identified. Within the prospective mineralization area, geological surveys and soil geochemical measurements were conducted at a scale of 1:10,000. The sampling density for soil geochemical measurements was 10 sampling points per square kilometer. The lithium, rubidium, and cesium contents in the soil samples were analyzed, and lithium anomaly contour lines were delineated. The inner zone of the lithium anomaly contour lines, i.e., lithium content ≥150 × 10⁻⁶, was defined as... -6 The area is defined as the primary target area. In this embodiment, the defined primary target area is 1.2 km long and 0.4 km wide.

[0024] In a preferred embodiment, step S200 involves establishing comprehensive detection profiles within the primary target area, perpendicular to the regional tectonic line or the strike of the pegmatite vein group. The spacing between adjacent comprehensive detection profiles is 100m-200m, and the distance between adjacent measuring points on the same comprehensive detection profile is 10m-20m. In this embodiment, five comprehensive detection profiles are established within the primary target area perpendicular to the northeast-trending tectonic line, with an adjacent profile spacing of 150m and a profile point spacing of 15m. High-density resistivity measurement, time-domain excited polarization measurement, ground-based gamma-ray spectroscopy measurement, and portable X-ray fluorescence spectroscopy for rapid on-site analysis are sequentially performed on each comprehensive detection profile.

[0025] The high-density resistivity method described above employs a Winner or Schlumberger apparatus, with a maximum electrode distance AB / 2 of 500 m. After acquiring apparent resistivity data, a resistivity profile is obtained through two-dimensional inversion. Granite pegmatite veins typically exhibit medium-to-high resistivity characteristics, with a resistivity range of 500 Ω·m to 3000 Ω·m. Spodumene-bearing granite pegmatites, due to their increased spodumene content, have slightly lower resistivity than pure quartz veins; after inversion, a continuous high-resistivity zone within the resistivity range of 300 Ω·m to 1500 Ω·m is identified.

[0026] The time-domain induced polarization method measurement and the high-density resistivity method measurement are performed simultaneously, with a power supply time of 2 seconds and a delay time of 150 ms. Polarizability data are collected. Due to the presence of a small amount of sulfide and the polarization effect at mineral interfaces, the polarizability of spodumene-bearing granite pegmatite ranges from 2% to 5%. The polarizability of carbonaceous slate is usually greater than 8%. By setting a polarizability threshold of 6%, false anomalies caused by carbonaceous slate are eliminated, and the anomaly range between 1.5% and 5.5% is retained.

[0027] The ground-based gamma spectroscopy measurement was performed using a portable gamma spectrometer with a single-point measurement time of 120 seconds. The measurement included potassium, uranium, thorium content, and total count rate. Lithium-bearing pegmatites are usually associated with rubidium and cesium, and have a moderate potassium content, ranging from 2% to 4%. Feldspar veins have a high potassium content, usually greater than 6%. The ratio of potassium content to thorium content, i.e., the potassium / thorium ratio, was calculated. A potassium / thorium ratio between 1.5 and 3.0 indicates a pegmatite vein.

[0028] The portable X-ray fluorescence spectrometry rapid on-site analysis utilizes a handheld X-ray fluorescence spectrometer with a single-point measurement time of 60 seconds. Surface rock debris is collected at the profile point, and the content of lithium-associated indicator elements rubidium and cesium is analyzed using the handheld X-ray fluorescence spectrometer. The sum of the rubidium and cesium contents (rubidium + cesium) is calculated to be greater than or equal to 200 × 10⁻⁶. -6 The points are marked as mineralization points.

[0029] The abnormal curves obtained by the above four methods were spatially superimposed, and the superposition rules were set as follows: resistivity within the range of 300 Ω·m-1500 Ω·m, polarizability within the range of 1.5% to 5.5%, potassium / thorium ratio within the range of 1.5 to 3.0, and rubidium + cesium content greater than or equal to 200 × 10⁻⁶. -6 When the length of a continuous section that meets all four conditions is greater than 50m, the section is designated as the precision positioning target area, and the center coordinates, orientation, and surface exposure width of the precision positioning target area are recorded.

[0030] In this embodiment, within the range of measuring points 260 to 380 of profile 2, at elevations of 3400m to 3480m, there exists a continuous high-resistivity band with a resistivity of 600Ω·m to 1200Ω·m, a polarizability of 2.2% to 3.8%, a potassium / thorium ratio of 1.9 to 2.7, and a rubidium + cesium content of 220 × 10⁻⁶. -6 Up to 380×10 -6 If all four conditions are met simultaneously, and the continuous section is 95m long, this section is designated as the precision positioning target area, with its center coordinates being east longitude and north latitude, its orientation being northeast 60°, and its surface exposed width being approximately 3m.

[0031] In a preferred embodiment, step S300 imports the resistivity and polarizability inversion data of all integrated detection profiles from step S200 into a three-dimensional visualization platform. A three-dimensional resistivity volume and a three-dimensional polarizability volume are generated using the Kriging interpolation method. Resistivity isosurfaces of 500 Ω·m and 1200 Ω·m are extracted from the three-dimensional resistivity volume. Regions with resistivity below 500 Ω·m are defined as surrounding rock areas, regions with resistivity above 1200 Ω·m are defined as quartz veins or cavities, and regions with resistivity between 500 Ω·m and 1200 Ω·m are defined as predicted pegmatite vein areas. The spatial region between the two resistivity isosurfaces represents the predicted three-dimensional spatial distribution of the pegmatite vein.

[0032] A verification borehole was designed based on the predicted occurrence of the pegmatite vein. The dip angle of the verification borehole was 5°-10° smaller than the dip angle of the predicted pegmatite vein. The designed depth of the verification borehole was 30m below the bottom plate of the predicted pegmatite vein.

[0033] In this embodiment, the inversion data of five profiles are imported into a three-dimensional platform to generate a three-dimensional resistivity volume. Isosurfaces of 500 Ω·m and 1200 Ω·m are extracted. The spatial region between the two isosurfaces is plate-shaped, dips southeast at an angle of 80°, and the predicted true thickness of the pegmatite vein is approximately 4.5 m. The top plate is buried at a depth of 35 m, and the bottom plate at a depth of 68 m. A verification borehole is designed with an inclination of 70°, which is 10° smaller than the predicted inclination of 80° for the pegmatite vein. The azimuth of the verification borehole is 120°, perpendicular to the strike of the vein. The designed borehole depth is 120 m, which means it passes through 52 m below the predicted bottom plate of the pegmatite vein (68 m). The borehole location is selected on a flat meadow on the centerline of the precise positioning target area, 80 m from the nearest stream.

[0034] In a preferred embodiment, step S400 involves using a lightweight portable hydraulic drill to drill and verify the verification borehole designed in step S300. The power system of the lightweight portable hydraulic drill is powered by a combination of photovoltaic panels and a lithium battery pack, and does not consume fossil fuels. Figure 2 As shown, Figure 2 The following is a flowchart of the drilling verification process in an embodiment of the present invention. The drilling verification process includes, in sequence: screening and pretreatment of local natural mineral matrix, on-site preparation of compounded environmentally friendly mud, layered adaptive drilling, core logging and rapid grade analysis, in-situ co-composting of drill cuttings and mud, and co-remediation of composted products and local vegetation.

[0035] In a preferred embodiment, the steps for screening and pretreatment of local natural mineral matrix are as follows: Claystone or weathered layer samples were collected within a 20km radius of the planned borehole, and the montmorillonite content in the samples was detected using a portable X-ray diffractometer. Natural kaolin or natural montmorillonite with a montmorillonite content of ≥60%, an expansion factor of ≥8, and heavy metal content below preset limits were selected as natural mud base materials. The selected natural mud base materials were crushed at the construction site and passed through a 200-mesh sieve to obtain pretreated natural mud base materials.

[0036] In this embodiment, a natural kaolin deposit was discovered 18 km around the planned borehole location. After sampling, a portable X-ray diffractometer was used for analysis. The results showed that the montmorillonite content was 72% and the expansion factor was 9. The natural kaolin deposit was used as a natural mud base material. The collected kaolin deposit was crushed at the construction site and passed through a 200-mesh sieve to obtain a total of 1.5 tons of pre-treated natural mud base material.

[0037] In a preferred embodiment, the on-site preparation steps of the compounded environmentally friendly mud are as follows: The pretreated natural mud base, biodegradable thickener, and bio-based wall-protecting agent are added to a mobile mud mixing device at a mass ratio of 80:15:5 for in-situ compounding. The mobile mud mixing device is powered by a photovoltaic panel. The biodegradable thickener is sodium carboxymethyl cellulose, and the bio-based wall-protecting agent is plant gum or modified starch. The stirring speed is 800 r / min to 1200 r / min, and the stirring time is not less than 20 min, to obtain compounded environmentally friendly mud. The performance indicators of the compounded environmentally friendly mud are controlled as follows: density 1.02 g / cm³-1.08 g / cm³, funnel viscosity 25 s-35 s, and water loss less than or equal to 12 mL / 30 min.

[0038] In this embodiment, 120 kg of pretreated natural mud base material, 22.5 kg of sodium carboxymethyl cellulose as a biodegradable thickener, and 7.5 kg of plant gum as a bio-based wall protectant were taken. The above three materials were added to a mobile mud mixing device, 150 L of clean water was injected, the stirring speed was set to 1000 r / min, and the stirring time was 25 min. The performance indicators of the compounded environmentally friendly mud were: density 1.05 g / cm³, funnel viscosity 33 s, and water loss 11.5 mL / 30 min.

[0039] In a preferred embodiment, the steps of layered adaptive drilling are as follows: Based on the lithology of the formation, the vertical depth of the borehole is divided into three sections, each with different drilling parameters.

[0040] The first layer is the surface layer, with a depth ranging from 0m to 5m below the ground surface. This surface layer includes meadow soil or loose debris slope deposits. The drilling speed for this layer is low (150-200 rpm), the pump flow rate is low (30-40 L / min), and the mud viscosity is set to 33-35 s. These parameters are used to prevent borehole wall collapse.

[0041] The second section is the central section, with a depth ranging from 5m below the ground surface to 10m above the predicted top of the ore body. This central section comprises metamorphic sandstone, slate, or granite. The drilling speed for this section is medium-speed (300-400 rpm), pump flow rate (50-70 L / min), and mud viscosity (30-32 s). These parameters are set to ensure efficient slag carrying capacity.

[0042] The third section is the ore-bearing section, which is the area after entering the spodumene pegmatite vein. In this section, the mud water loss is reduced to less than or equal to 10 mL / 30 min, the drilling speed is reduced to 200-250 r / min, the pump flow rate is maintained at 50 L / min, and the mechanical drilling rate is controlled at 0.5 m / h-1.0 m / h. These parameters are set to prevent the spodumene from softening upon contact with water and to protect the integrity of the core.

[0043] During drilling, record the amount of drilling mud consumed, the color of the returned water, and the characteristics of the core sample after each trip. When spodumene appears in the core sample, immediately adjust the drilling mud properties and reduce the mechanical drilling rate. The identifying characteristics of spodumene are: grayish-white color, vitreous luster, and well-developed cleavage.

[0044] In this embodiment, the drilling process is as follows: The surface section from 0m to 4.2m consists of meadow soil and gravel. Using parameters of 180 r / min rotation speed, 35 L / min pump flow rate, and 35 s mud viscosity, we successfully traversed this section.

[0045] The middle section, from 4.2m to 38m, consisted of metamorphic sandstone and slate. Using parameters of 350 rpm, 60 L / min pump flow rate, and 32 s mud viscosity, with a mechanical drilling rate of 2.0 m / h, spodumene began to appear in the core sample at a depth of 38m, with a spodumene content of approximately 15%, indicating the entry into a ore-bearing zone. The mud flow rate was immediately adjusted to 9.5 mL / 30min, the rpm was reduced to 220 rpm, the pump flow rate was maintained at 50 L / min, and the mechanical drilling rate was reduced to 0.8 m / h. The ore-bearing zone had a continuous mineralization length of 6.2m, from depth 38m to 44.2m, with a lithium-rich section containing more than 30% spodumene and a thickness of 3.5m. After reaching a depth of 44.2m, the core sample changed to hornfels, indicating entry into the bottom surrounding rock. The parameters for the middle section were restored, and drilling continued to the designed depth of 120m.

[0046] In a preferred embodiment, the steps of core logging and rapid grade analysis are as follows: After each core sample is retrieved, it is cleaned, sorted, and numbered, and a core label is affixed. Geological logging personnel observe and record lithological, mineralization, and alteration characteristics layer by layer. Semi-quantitative rapid lithium content analysis is performed on the core section using a handheld laser-induced breakdown spectrometer or a portable X-ray fluorescence spectrometer, with measurements taken at points every 0.5 m. The industrial ore body boundary is delineated on-site. The core section is cut in half; one half is sent to the laboratory for chemical analysis as a test sample, while the other half is preserved as a specimen in the core repository.

[0047] In this embodiment, after each core sample was retrieved, the mud on the surface of the core was washed off with clean water. The cores were arranged in descending order of depth, and each section was marked with a depth number and a core tag was placed in the corresponding position. Geological logging personnel observed and recorded the lithology, mineralization, and alteration characteristics layer by layer. For the 38m-44.2m core section, a handheld laser-induced breakdown spectrometer was used every 0.5m for rapid semi-quantitative lithium content analysis. The analysis results showed that the average lithium oxide content in the 38m-40m section was 0.85%, and the average lithium oxide content in the 40m-44.2m section was 1.62%. Based on the analysis results, the industrial ore body boundary was delineated on-site as 38m-44.2m. This core section was cut in half along its axis; one half was bagged and sent to the laboratory for chemical analysis, while the other half was packed in boxes and stored in the core repository in sequence.

[0048] In a preferred embodiment, the step of in-situ co-adsorption of drill cuttings and drilling mud is as follows: A seepage-proof composting tank is constructed near the borehole. The bottom of the tank is lined with geotextile and a 10cm thick layer of gravel. Drill cuttings discharged during drilling are mixed with residual drilling mud at a volume ratio of 3:1, and a compound microbial agent is added to obtain a mixture. The compound microbial agent contains Bacillus subtilis, Pseudomonas, and yeast. The total viable count of the compound microbial agent is greater than or equal to 1×10⁻⁶.8 CFU / g. The compound microbial agent is added at a rate of 2 kg per cubic meter of the mixture. The mixture is then subjected to aerobic fermentation in the impermeable composting tank, with the pile turned over every 3 days during fermentation. The fermentation period is 15-30 days. When the local temperature is below 10℃, the mixture is covered with a black insulating film, and the fermentation period is extended to 40 days. The fermentation endpoint is determined by the following criteria: no odor from the material, the material temperature drops to ambient temperature, the material pH value is 6.5-7.5, and the material organic matter content is greater than or equal to 8%. After fermentation, a composted product is obtained, which serves as the ecological restoration substrate.

[0049] In this embodiment, a seepage-proof composting tank was excavated 10m downwind of the borehole. The tank was 5m long, 3m wide, and 1m deep. A layer of geotextile was laid at the bottom, followed by a 10cm thick layer of gravel. Drill cuttings (2.4m³) and residual drilling mud (0.8m³) were collected during drilling. The drill cuttings and residual drilling mud were mixed at a volume ratio of 3:1, and 6.4kg of a compound microbial agent was added. The total viable count of Bacillus subtilis, Pseudomonas aeruginosa, and yeast in the compound microbial agent was 1.2 × 10⁻⁶. 8 CFU / g. The mixture was piled into trapezoidal windrows and covered with black insulating film. The average ambient temperature was 6℃, below 10℃, hence the covering with insulating film and extended fermentation period. The pile was turned every 3 days during fermentation. After 35 days of fermentation, the material turned dark brown, odorless, the temperature dropped to ambient temperature, the pH value was measured to be 6.9, and the organic matter content was measured to be 9.2%, reaching the fermentation endpoint. Composting was complete, and the composted product was obtained as an ecological restoration substrate.

[0050] In a preferred embodiment, the step of co-remediation of decomposed products and native vegetation is as follows: After drilling is completed, the decomposed material is directly backfilled into the disturbed area surrounding the borehole. This disturbed area includes the rig leveling area, mud pit, and access road. The backfill thickness of the decomposed material is 10-15 cm. Native dominant plant seeds are collected within a 500m radius of the disturbed area. For areas above 3500m altitude, the selected native dominant plant seeds are *Kobresia oleracea*, *Leymus chinensis*, and *Poa annua*. For areas below 3500m altitude or arid areas, the selected native dominant plant seeds are *Salix matsudana* and *Hippophae rhamnoides*. The native dominant plant seeds are mixed with the decomposed material surface at a sowing rate of 15-20g per square meter. During the seed germination period, nearby stream water is drawn using a photovoltaic water pump for drip irrigation. The drip irrigation frequency is once every two days, wetting the top 10cm each time. The drip irrigation lasts for two months. After the irrigation period, the vegetation coverage is measured, requiring a coverage rate of no less than 70%.

[0051] In this embodiment, after the drilling rig is withdrawn, the decomposed product obtained in sub-step S450 is evenly backfilled into the disturbed area. The disturbed area includes a 30m² leveled area for the drilling rig and a 50m long and 2m wide access road. The backfill thickness is 12cm. Seeds of Kobresia alpineae and Leymus chinensis are collected within a 500m radius of the borehole and mixed at a 1:1 mass ratio. The mixed seeds are then mixed with the surface of the decomposed product at a sowing rate of 18g per square meter. During the seed germination period (May-June after snowmelt in the local area), water is drawn from a nearby stream using a photovoltaic water pump for drip irrigation. The drip irrigation frequency is once every two days, with 15 minutes of drip irrigation each evening, wetting the top 10cm. This irrigation continues for two months. After two months, the vegetation coverage rate reaches 82%. After three months, there is no visible difference between the vegetation and the surrounding meadow.

[0052] In a preferred embodiment, step S500 feeds back the actual occurrence, thickness, and grade of the ore body revealed by drilling in step S400 to the three-dimensional resistivity volume and the three-dimensional polarizability volume generated in step S300, corrects the quantitative relationship between resistivity and lithium grade, and obtains a corrected three-dimensional geological-geophysical model.

[0053] If the actual mineralization thickness or grade of the verified borehole is less than 70% of the predicted value, a new infill borehole will be drilled within a 50m radius of the original verified borehole. If the actual mineralization of the verified borehole is better than the predicted value, a new verified borehole will be drilled 100m outward from the predicted pegmatite vein.

[0054] In this embodiment, the actual burial depth of the top plate of the ore body revealed by drilling was 38m, while the predicted value was 35m, resulting in an error of 3m. The actual burial depth of the bottom plate of the ore body was 44.2m, while the predicted value was 68m, showing a significant error. The actual ore body thickness was 6.2m, with a high grade, but no extension to 68m was observed at depth. The reason for this was that the geophysical model misidentified the deep hornfels alteration zone as a pegmatite vein. The resistivity of the hornfels alteration zone (approximately 800 Ω·m) was removed from the pegmatite properties, and the upper limit of the resistivity threshold was reset to 1100 Ω·m to correct the three-dimensional resistivity volume. The corrected model was used for borehole design in adjacent target areas. Due to the deviation between the actual ore-bearing effect and the predicted value, but with the actual ore grade being better than the predicted value, the next verification borehole was laid out 100m outward along the predicted pegmatite vein strike.

[0055] In a preferred embodiment, step S600 estimates the lithium resource quantity using the geological block method or the Kriging method based on the chemical analysis results of all verification boreholes, and delineates the three-dimensional boundary of the oreable body.

[0056] In this embodiment, based on the chemical analysis results of the verification borehole and the subsequent nine verification boreholes, the geological block method was used to estimate the resource quantity. The delineated oreable body has a length of 480m, a dip depth of 120m to 200m, an average thickness of 4.8m, and an average lithium oxide grade of 1.35%. The estimated lithium oxide resource quantity is 86,000 tons, and the associated rubidium, cesium, and tantalum all meet the comprehensive utilization index.

[0057] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for precise location detection of lithium granite pegmatite vein ore bodies, characterized in that, The steps of this method are as follows: S100, based on water system sediment measurements and soil geochemical measurements, delineated the lithium element anomaly zone as a primary target area; S200. Within the primary target area, deploy comprehensive detection profiles with a profile spacing of 100-200m and a point spacing of 10-20m. On each profile, sequentially collect high-density resistivity data, time-domain excited polarizability data, ground-based gamma-ray energy spectrum data, and portable X-ray fluorescence spectrum data. Data must simultaneously meet the following criteria: resistivity 300-1500 Ω·m, polarizability 1.5%-5.5%, potassium / thorium ratio 1.5-3.0, and rubidium + cesium content ≥200 × 10⁻⁶. -6 The continuous segment was determined as the precise positioning target area; S300. Import the resistivity inversion data and polarizability inversion data of all integrated detection profiles into the three-dimensional visualization platform to generate a three-dimensional resistivity volume and a three-dimensional polarizability volume. Extract the resistivity isosurfaces 500Ω·m and 1200Ω·m from the three-dimensional resistivity volume. Determine the spatial region between the two isosurfaces as the predicted pegmatite vein. Design and verify the borehole based on the occurrence of the predicted pegmatite vein. S400. The verification borehole is drilled and verified using a hydraulic drilling rig. The drilling and verification process includes the following steps: screening and pretreatment of local natural mineral matrix, on-site preparation of compounded environmentally friendly mud, layered adaptive drilling, core logging and rapid grade analysis, in-situ co-composting of drill cuttings and mud, and co-remediation of composted products and local vegetation. S500: Feedback the actual occurrence, thickness and grade of the ore body revealed by S400 drilling to the three-dimensional resistivity volume and three-dimensional polarizability volume generated by S300 for comparison and correction, and correct the quantitative relationship between resistivity and lithium grade. S600. Based on the chemical analysis results of all verification boreholes, estimate the lithium resource quantity using the geological block method or the Kriging method, and delineate the three-dimensional boundary of the oreable body.

2. The method for precise location and detection of lithium granite pegmatite vein ore bodies according to claim 1, characterized in that, In S200, the high-density resistivity data is obtained by measuring the high-density resistivity method. The high-density resistivity method measurement uses a Winner device or a Schlumberger device, and the maximum electrode distance AB / 2 is 500m. The time-domain induced polarizability data were obtained by measuring the time-domain induced polarizability method. The time-domain induced polarizability method measurement was performed synchronously with the high-density resistivity method measurement. The power supply time was 2 seconds and the delay time was 150 ms. Ground-based gamma-ray spectrometer data were obtained using a portable gamma-ray spectrometer, with a single-point measurement time of 120 seconds. Portable X-ray fluorescence spectroscopy data were obtained using a handheld X-ray fluorescence spectrometer, with a single-point measurement time of 60 seconds.

3. The method for precise location and detection of lithium granite pegmatite vein ore bodies according to claim 1, characterized in that, In step S400, the screening and pretreatment steps of the local natural mineral matrix are as follows: Claystone or weathered layer samples were collected within a 20km radius of the planned borehole, and the montmorillonite content in the samples was detected using a portable X-ray diffractometer. Natural kaolin or natural montmorillonite with a montmorillonite content ≥60%, an expansion factor ≥8 times, and a heavy metal content below the preset limit was selected as the natural mud base material. The selected natural mud base material is crushed at the construction site and passed through a 200-mesh sieve to obtain pretreated natural mud base material.

4. The method for precise location and detection of lithium granite pegmatite vein ore bodies according to claim 1, characterized in that, In S400, the on-site preparation steps of the compounded environmentally friendly mud are as follows: The pretreated natural mud base, biodegradable thickener and bio-based wall protector were added to a mobile mud mixing device at a mass ratio of 80:15:5 for in-situ compounding. The biodegradable thickener is sodium carboxymethyl cellulose, and the bio-based wall-protecting agent is plant gum or modified starch; The mixing speed is 800-1200 r / min, and the mixing time is ≥20 min to obtain a compound environmentally friendly slurry; The performance indicators of the compounded environmentally friendly mud are controlled as follows: density 1.02-1.08 g / cm³, funnel viscosity 25-35 s, and water loss ≤12 mL / 30 min.

5. The method for precise location and detection of lithium granite pegmatite vein ore bodies according to claim 1, characterized in that, In S400, the steps of the layered adaptive drilling are as follows: Based on the lithology of the strata, the vertical depth of the borehole is divided into three sections, and different drilling parameters are used for each section. The first layer is the surface layer, with a depth range of 0-5m. The surface layer includes meadow soil or loose deposits on scree slopes. The surface layer uses a low rotation speed of 150-200 r / min, a low pump flow rate of 30-40 L / min, and a mud viscosity of 33-35s. The second section is the middle section, with a depth range of 5m to 10m above the predicted top plate of the ore body. The middle section includes metamorphic sandstone, slate or granite. The middle section uses a medium rotation speed of 300-400r / min, a medium pump flow rate of 50-70L / min, and a mud viscosity of 30-32s. The third section is the mineralization section, which is the section after entering the spodumene pegmatite vein. In this section, the mud water loss is reduced to ≤10mL / 30min, the rotation speed is reduced to 200-250r / min, the pump flow rate is maintained at 50L / min, and the mechanical drilling rate is controlled at 0.5-1.0m / h. During the drilling process, the amount of mud consumed, the color of the returned water, and the characteristics of the core were recorded after each drilling operation. When spodumene appeared in the core, the mud properties were adjusted and the mechanical drilling speed was reduced.

6. The method for precise location and detection of lithium granite pegmatite vein ore bodies according to claim 1, characterized in that, In S400, the steps for core logging and rapid grade analysis are as follows: After each core sample is retrieved, the core samples are cleaned, sorted, and numbered, and a core tag is filled out. Observe and record the lithological, mineralization, and alteration characteristics layer by layer; Semi-quantitative rapid analysis of lithium content in the core section was performed using a handheld laser-induced breakdown spectrometer or a portable X-ray fluorescence spectrometer, with measurements taken at a point every 0.5m, and the boundary line of the industrial ore body was delineated on site. The core section was cut in half. One half was sent to the laboratory as a test sample for chemical analysis, while the other half was preserved as a specimen in the core bank.

7. The method for precise location and detection of lithium granite pegmatite vein ore bodies according to claim 1, characterized in that, In S400, the step of in-situ co-fermentation of drill cuttings and drilling mud is as follows: An impermeable composting tank is set up near the borehole, and the bottom of the impermeable composting tank is covered with geotextile and a 10cm thick layer of sand and gravel. Drill cuttings discharged during drilling are mixed with residual drilling mud at a volume ratio of 3:1, and a compound microbial agent is added to obtain a mixture. The compound microbial agent contains Bacillus subtilis, Pseudomonas, and yeast, and the total viable count of the compound microbial agent is ≥1×10⁻⁶. 8 CFU / g, the amount of compound microbial agent added is 2kg of agent per cubic meter of the mixture; The mixture is subjected to aerobic fermentation in the seepage-proof composting tank. During the fermentation period, the mixture is turned over every 3 days, and the fermentation cycle is 15-30 days. When the local temperature is below 10℃, cover with black insulating film and extend the fermentation period to 40 days; The criteria for determining the fermentation endpoint are: the material has no odor, the material temperature drops to ambient temperature, the material pH value is 6.5-7.5, and the material organic matter content is ≥8%. After fermentation, a decomposed product is obtained, which is the ecological restoration substrate.

8. The method for precise location and detection of lithium granite pegmatite vein ore bodies according to claim 1, characterized in that, In S400, the steps for the co-remediation of decomposed products and native vegetation are as follows: After all drilling work is completed, the decomposed product is directly backfilled into the disturbed area around the borehole. The disturbed area around the borehole includes the machine platform leveling area, mud pit and construction access road. The backfilling and spreading thickness of the decomposed product is 10-15cm. Seeds of native dominant plants were collected within 500m of the disturbance area around the borehole. For areas above 3500m altitude, the native dominant plant seeds were selected from Kobresia alpinea, Leymus chinensis, and Poa lanceolata. For areas below 3500m altitude or arid areas, the native dominant plant seeds were selected from Tamarix chinensis and Hippophae rhamnoides. The native dominant plant seeds were mixed with the surface of the decomposed product at a sowing rate of 15-20g / ㎡. During the seed germination period, a photovoltaic water pump is used to draw stream water for drip irrigation and maintenance. The drip irrigation and maintenance is carried out once every 2 days, and the surface layer is moistened by 10cm each time. The drip irrigation and maintenance lasts for 2 months. After the maintenance period, the vegetation coverage rate should be calculated, and the vegetation coverage rate should be ≥70%.

9. The method for precise location and detection of lithium granite pegmatite vein ore bodies according to claim 1, characterized in that, In S500, the comparison correction includes: If the actual ore thickness or the actual ore grade of the verification borehole is less than 70% of the predicted value, then an additional densification borehole shall be added within a 50m radius around the original verification borehole. If the actual mineralization of the verification borehole is greater than the predicted value, then the next verification borehole is laid out 100m outward along the predicted pegmatite vein.

10. The method for precise location and detection of lithium granite pegmatite vein ore bodies according to claim 1, characterized in that, In S300, the three-dimensional resistivity volume and the three-dimensional polarizability volume are interpolated using the Kriging interpolation method. When extracting the resistivity isosurfaces 500 Ω·m and 1200 Ω·m from the three-dimensional resistivity volume, the area with resistivity below 500 Ω·m is defined as the surrounding rock area. Regions with resistivity higher than 1200 Ω·m are defined as quartz veins or void regions. The region with resistivity between 500 Ω·m and 1200 Ω·m was identified as the predicted area for ore-bearing pegmatite veins.

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