A method for determining the potential of a tectonic unit to produce sandstone-type uranium deposits

Abstract

This application provides a method for determining the potential of tectonic units to produce sandstone-type uranium deposits, belonging to the field of uranium exploration technology. The method includes: dividing the sedimentary basin area into tectonic compression zones, tectonic extension zones, and tectonic strike-slip zones; determining the type of metallogenic block for sandstone-type uranium deposits; determining the type of metallogenic tectonic unit and favorable metallogenic tectonic units; rapidly delineating metallogenic tectonic units based on the ability of each metallogenic block to produce different types of metallogenic tectonic units; and analyzing the delineated metallogenic tectonic units to determine the first-order favorable metallogenic tectonic unit types. This application utilizes the significant control effect of tectonic unit boundaries on the mineralization of sandstone-type uranium deposits, systematically evaluates the metallogenic potential of different tectonic units, and identifies tectonic units with metallogenic advantages. This allows for precise targeting of preferred exploration areas for sandstone-type uranium deposits, opening up new directions for promoting uranium prospecting practices.

Description

Technical Field

[0001] This application relates to the field of uranium exploration technology, specifically to a method for determining the potential of a tectonic unit to produce sandstone-type uranium deposits. Background Technology

[0002] In the field of uranium exploration, sandstone-type uranium deposits have become the primary target type for increasing uranium reserves due to their significant advantages such as large deposit scale, low mining costs, and minimal environmental impact. Recent studies indicate a close relationship between the spatial distribution of uranium deposits and the boundaries of tectonic units; these boundary areas should be prioritized for sandstone-type uranium exploration. However, the geological characteristics of different tectonic units within sedimentary basins vary significantly, and not all tectonic units possess uranium mineralization conditions. Therefore, conducting a preliminary evaluation of favorable mineralization tectonic units is a crucial prerequisite for uranium exploration in boundary areas. Against this backdrop, how to scientifically and effectively determine the potential of tectonic units to produce sandstone-type uranium deposits has become an urgent problem to be solved. Summary of the Invention

[0003] To address the problems existing in the prior art, this application provides a method for determining the potential for sandstone-type uranium deposits within a tectonic unit, thereby solving the technical problem that existing uranium prospecting methods are not very effective. The method includes:

[0004] The tectonic activity characteristics of the sedimentary basin area are obtained, and the area is divided into tectonic compression zone, tectonic extension zone, and tectonic strike-slip zone based on the tectonic activity characteristics.

[0005] Analyze the direction of tectonic stress fields and / or the intensity of tectonic activity in the tectonic compression zone, tectonic extension zone, and tectonic strike-slip zone, and determine the type of ore-forming block for sandstone-type uranium deposits based on the direction of tectonic stress fields and / or the intensity of tectonic activity.

[0006] Based on the characteristics of proven sandstone-type uranium deposits and their spatiotemporal relationship with metallogenic tectonic units, the types of metallogenic tectonic units and favorable metallogenic tectonic units are determined.

[0007] Based on the ability of each metallogenic block to produce different types of metallogenic tectonic units, quickly delineate the metallogenic tectonic units;

[0008] The delineated metallogenic tectonic units were analyzed to determine the types of first-order favorable metallogenic tectonic units.

[0009] Furthermore, the direction of tectonic stress fields and / or the intensity of tectonic activity in the tectonic compression zone, tectonic extension zone, and tectonic strike-slip zone are analyzed. Based on the direction of tectonic stress fields and / or the intensity of tectonic activity, the type of sandstone-type uranium deposit is determined, including:

[0010] The boundary lines of the sedimentary basin are divided into boundary lines A, C, B, and D in sequence. Boundary lines A and B are opposite each other, and boundary lines C and D are opposite each other. The area less than or equal to 50 km from the boundary line into the basin is called the marginal area, and the area greater than 50 km from the boundary line into the basin is called the central area of ​​the basin.

[0011] The tectonic compression zone is highly tectonic. If the tectonic stress field acts from boundary line A to boundary line B, the edge areas of the sedimentary basin near boundary line B, the edge areas near boundary line C, and the edge areas near boundary line D are classified as Class I metallogenic blocks; the central area of ​​the basin is classified as Class II metallogenic blocks; and the edge areas of the sedimentary basin near boundary line B are classified as Class III metallogenic blocks.

[0012] The tectonic activity intensity of the strike-slip zone is moderate. The marginal area of ​​the sedimentary basin and the area in the middle of the sedimentary basin where volcanic activity has occurred since the Mesozoic and Cenozoic are divided into four types of metallogenic blocks.

[0013] The tectonic activity in the tectonic extension zone is weak. If the tectonic stress field acts from the direction of boundary line A to the direction of boundary line B, the marginal area of ​​the sedimentary basin near boundary line A and the area in the middle of the sedimentary basin where volcanic activity has occurred since the Mesozoic and Cenozoic eras will be divided into five types of metallogenic blocks.

[0014] Furthermore, the determination of tectonic unit types and favorable metallogenic tectonic units based on the proven characteristics of sandstone-type uranium deposits and their spatiotemporal relationship with tectonic units includes:

[0015] The mineralization tectonic units are divided into basement-exposed tectonic unit assemblages and deep fluid-supplying tectonic units. The basement-exposed tectonic unit assemblages include tectonic unit A and tectonic unit B, where tectonic unit B is adjacent to a relatively uplifted tectonic unit A with exposed bedrock, and tectonic unit B is a favorable mineralization tectonic unit. The deep fluid-supplying tectonic units include hydrocarbon accumulation tectonic units and magmatic-hydrothermal intrusion tectonic units, where hydrocarbon accumulation tectonic units and magmatic-hydrothermal intrusion tectonic units are favorable mineralization tectonic units.

[0016] Furthermore, the capacity of each metallogenic block to produce different types of metallogenic tectonic units is as follows:

[0017] The ability of Class I, Class II, Class III, Class IV and Class V metallogenic blocks to produce basement outcrop tectonic unit combinations decreases sequentially.

[0018] The ability of Class I, Class II, Class III, Class IV and Class V metallogenic blocks to produce deep fluid-supplying tectonic units increases sequentially.

[0019] Furthermore, the analysis of the delineated metallogenic tectonic units to determine the types of first-order favorable metallogenic tectonic units includes:

[0020] For the basement-exposed structural unit combination, analyze the lithological characteristics of the exposed bedrock of structural unit A, and determine the first-order favorable metallogenic structural unit type based on the lithological characteristics of the exposed bedrock of structural unit A.

[0021] For deep fluid-supply type tectonic units, the type of first-order favorable mineralization tectonic unit is determined by measuring the soil hydrocarbon gas at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region and measuring the helium gas at the boundary of the hydrocarbon accumulation tectonic unit.

[0022] Furthermore, for the basement-exposed structural unit assemblage, the lithological characteristics of the exposed bedrock in structural unit A are analyzed. Based on these lithological characteristics, the first-order favorable mineralization structural unit types are classified, including:

[0023] If the bedrock exposed in tectonic unit A is intermediate volcanic rock, acidic volcanic rock, or granite, then tectonic unit B is classified as a type of favorable mineralization tectonic unit.

[0024] If the bedrock exposed in tectonic unit A is metamorphic rock or basic volcanic rock, then tectonic unit B is classified into two types of favorable mineralization tectonic units.

[0025] Furthermore, after analyzing the lithological characteristics of the bedrock exposed in structural unit A, and determining the type of first-order favorable metallogenic structural unit based on the lithological characteristics of the bedrock exposed in structural unit A, the process further includes:

[0026] The uranium supply capacity of the exposed bedrock in structural unit A is analyzed, and the type of secondary favorable mineralization structural unit is determined based on the uranium supply capacity of the exposed bedrock in structural unit A.

[0027] Furthermore, based on the uranium supply capacity of the bedrock exposed in the analytical structural unit A, the types of secondary favorable mineralization structural units are determined, including:

[0028] Tectonic unit A, where the bedrock is exposed, is designated as the erosion source area;

[0029] Rock samples of different lithologies were collected from the bedrock outcrop area, and the samples were analyzed to calculate the chemical weathering index and the average Th / U value.

[0030] Based on the chemical weathering index and average Th / U value, the uranium supply capacity of the exposed bedrock in tectonic unit A is analyzed.

[0031] Based on the chemical weathering index and average Th / U value, combined with the analysis results of the uranium supply capacity of the exposed bedrock of tectonic unit A, the type of secondary favorable mineralization tectonic unit is determined.

[0032] Furthermore, the analysis of the uranium supply capacity of the exposed bedrock in tectonic unit A based on the chemical weathering index and average Th / U value includes:

[0033] If the chemical weathering index (CIA) value is greater than 0.8 and less than or equal to 1, it indicates that the exposed bedrock has undergone strong chemical weathering, which is conducive to uranium leaching and can provide abundant uranium sources for uranium mineralization.

[0034] If the chemical weathering index (CIA) is greater than 0.6 and less than or equal to 0.8, it indicates that the exposed bedrock has undergone moderate chemical weathering, and some uranium may be leached out, which can provide a considerable uranium source for uranium mineralization.

[0035] If the chemical weathering index (CIA) is greater than 0.5 and less than or equal to 0.6, it indicates that the exposed bedrock has undergone weak chemical weathering, and the leaching of uranium is relatively small, but it can still provide the uranium source required for uranium mineralization.

[0036] If the average Th / U value is greater than 10, it indicates that the leaching of uranium in the exposed bedrock is significant and can provide abundant uranium sources for uranium mineralization.

[0037] If the average Th / U value is greater than 7 and less than or equal to 10, it indicates that there is significant uranium leaching in the exposed bedrock, which can provide a considerable uranium source for uranium mineralization.

[0038] If the average Th / U value is greater than 4 and less than or equal to 7, it indicates that the degree of uranium leaching in the exposed bedrock is not high, but it can still provide the uranium source required for uranium mineralization.

[0039] Furthermore, based on the chemical weathering index and average Th / U value, combined with the analysis results of the uranium supply capacity of the exposed bedrock of tectonic unit A, the types of secondary favorable mineralization tectonic units are determined, including:

[0040] If the bedrock chemical weathering index (CIA) of the exposed tectonic unit A adjacent to a type of favorable metallogenic tectonic unit is greater than 0.6 and the average Th / U value is greater than 7, then the type of favorable metallogenic tectonic unit is identified as a key prospecting tectonic unit.

[0041] If the bedrock chemical weathering index (CIA) of the exposed bedrock of a type of favorable metallogenic structural unit A is greater than 0.6 or the average Th / U value is greater than 7, then the type of favorable metallogenic structural unit is identified as a key prospecting structural unit.

[0042] If the chemical weathering index (CIA) of the bedrock exposed in structural unit A adjacent to a type of favorable metallogenic structural unit is less than 0.6 and the average Th / U value is less than 7, then the type of favorable metallogenic structural unit is identified as a general prospecting structural unit.

[0043] If the bedrock chemical weathering index (CIA) of the exposed bedrock of the adjacent tectonic unit A of the second type of favorable metallogenic tectonic unit is greater than 0.6 and the average Th / U value is greater than 7, then the second type of favorable metallogenic tectonic unit is identified as a key prospecting tectonic unit.

[0044] If the bedrock chemical weathering index (CIA) of the exposed bedrock of the adjacent tectonic unit A of type II favorable metallogenic tectonic unit is greater than 0.6 or the average Th / U value is greater than 7, then the type II favorable metallogenic tectonic unit is determined to be a general prospecting tectonic unit.

[0045] Furthermore, for deep fluid-supply type tectonic units, the type of first-order favorable mineralization tectonic unit is determined by measuring soil hydrocarbon gases at the boundaries of hydrocarbon accumulation tectonic units in the basin margin region and measuring helium gases at the boundaries of magmatic hydrothermal intrusion tectonic units, including:

[0046] Measuring soil hydrocarbon gases at the boundaries of hydrocarbon accumulation tectonic units in the basin margin region to determine the types of first-order favorable mineralization tectonic units:

[0047] If the hydrocarbon gas content at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region is measured to be greater than or equal to three times the background value of the region, then the hydrocarbon accumulation tectonic unit is identified as a favorable mineralization tectonic unit of type A1.

[0048] If the hydrocarbon gas content at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region is measured to be greater than 1 times the background value of the region and less than or equal to 2 times the background value of the region, then the hydrocarbon accumulation tectonic unit is identified as a B1 type favorable mineralization tectonic unit.

[0049] If the hydrocarbon gas content at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region is found to be comparable to the background value of the region, then the hydrocarbon accumulation tectonic unit is identified as a C1 type favorable mineralization tectonic unit.

[0050] Measure the helium gas at the boundary of the magmatic hydrothermal intrusion tectonic unit and calculate 3 He / 4 The He ratio determines the type of primary favorable metallogenic tectonic unit:

[0051] like 3 He / 4 If the He ratio is greater than or equal to 6Ra, the magmatic hydrothermal intrusion tectonic unit is classified as a favorable mineralization tectonic unit of type A2.

[0052] like 3 He / 4 If the He ratio is greater than or equal to 0.1Ra and less than or between 6Ra, the magmatic hydrothermal intrusion tectonic unit is classified as a B2 type favorable mineralization tectonic unit.

[0053] like 3 He / 4 If the He ratio is less than 0.1Ra, the magmatic hydrothermal intrusion tectonic unit is classified as a C2 type favorable mineralization tectonic unit.

[0054] Furthermore, for deep fluid-supply type structural units, the type of first-order favorable mineralization structural unit is determined by measuring the soil hydrocarbon gas at the boundary of the hydrocarbon accumulation structural unit in the basin margin region and measuring the helium gas at the boundary of the hydrocarbon accumulation structural unit. After determining the type of first-order favorable mineralization structural unit, the method further includes:

[0055] Based on the superposition of primary favorable metallogenic tectonic units, the types of secondary favorable metallogenic tectonic units are determined.

[0056] Furthermore, determining the type of secondary favorable metallogenic tectonic unit based on the superposition of primary favorable metallogenic tectonic units includes:

[0057] The superimposed structural unit of favorable mineral-forming structural units of type A1 and type A2 is identified as the key prospecting structural unit.

[0058] Superimposed structural units of favorable mineral-forming structural units of type A1 and type B2, or superimposed structural units of favorable mineral-forming structural units of type A2 and type B1, are identified as key prospecting structural units.

[0059] Superimposed structural units of type A1 and type C2 favorable mineral-forming structural units, or superimposed structural units of type A2 and type C1 favorable mineral-forming structural units, or superimposed structural units of type B1 and type B2 favorable mineral-forming structural units, are identified as general mineral exploration structural units.

[0060] This application conducts a macroscopic classification of sandstone-type uranium mineralization blocks based on the direction of regional tectonic stress fields and the intensity of tectonic activity. Based on the proven mineralization characteristics of sandstone-type uranium deposits and their spatiotemporal coupling relationship with tectonic units, favorable mineralization tectonic units are divided into two categories: basement-outcrop type and deep fluid-supply type. For basement-outcrop type tectonic units, the lithological characteristics of the bedrock are systematically analyzed through comprehensive interpretation of aeromagnetic data and field outcrop surveys. Chemical weathering index (CIA) and Th / U ratio tests are conducted on outcrop profiles to achieve subclassification and hierarchical evaluation of dominant tectonic units. For deep fluid-supply type tectonic units, the organic matter content of target strata and the identification of hydrocarbon accumulation tectonic units are first completed through geological data analysis. Based on this, soil hydrocarbon gas and soil helium measurements are conducted along the boundaries of hydrocarbon accumulation tectonic units to effectively capture hydrocarbon escape and deep thermal fluid activity signals, ultimately establishing a mineralization potential evaluation system for deep fluid-supply type tectonic units.

[0061] Compared with existing technologies, this application utilizes the significant control of tectonic unit boundaries on the mineralization of sandstone-type uranium deposits, systematically evaluates the mineralization potential of sandstone-type uranium deposits in different tectonic units, and identifies tectonic units with mineralization advantages. This can provide scientific guidance for the determination of prospective areas for sandstone-type uranium deposits and open up new directions for promoting uranium exploration practices. Attached Figure Description

[0062] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0063] Figure 1 This is a flowchart illustrating a method for determining the potential of a tectonic unit to produce sandstone-type uranium deposits, as provided in an embodiment of this application.

[0064] Figure 2 This is a schematic diagram of a sedimentary basin boundary provided in an embodiment of this application. Detailed Implementation

[0065] To better understand the technical solution of the present invention, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0066] It should be understood that 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 inventive effort are within the scope of protection of the present invention.

[0067] Step S1: Obtain the tectonic activity characteristics of the area where the sedimentary basin is located, and divide the area where the sedimentary basin is located into tectonic compression zone, tectonic extension zone and tectonic strike-slip zone according to the tectonic activity characteristics.

[0068] Step S2: Analyze the direction of tectonic stress field and / or intensity of tectonic activity in the tectonic compression zone, tectonic extension zone and tectonic strike-slip zone, and determine the type of ore-forming block of sandstone-type uranium deposit based on the direction of tectonic stress field and / or intensity of tectonic activity;

[0069] Moderate tectonic activity is favorable for uranium mineralization, while excessively strong or weak tectonic activity is detrimental. Excessively strong tectonic activity, with its thrusting, hinders the flow of ore-forming fluids towards the ore-bearing strata; conversely, insufficient tectonic activity may fail to guide the flow of ore-forming fluids.

[0070] like Figure 2 As shown, the boundary line of the sedimentary basin is divided into boundary line A, boundary line C, boundary line B and boundary line D in sequence. Boundary line A and boundary line B are opposite each other, and boundary line C and boundary line D are opposite each other. The area less than or equal to 50 km from the boundary line of the sedimentary basin into the basin is called the marginal area, and the area greater than 50 km from the boundary line of the sedimentary basin into the basin is called the central area of ​​the basin.

[0071] The tectonic compression zone is highly active. If the tectonic stress field acts from boundary line A to boundary line B, the edge areas of the sedimentary basin near boundary line B, C, and D are classified as Class I metallogenic blocks; the central area of ​​the basin is classified as Class II metallogenic blocks; and the edge areas of the sedimentary basin near boundary line B are classified as Class III metallogenic blocks.

[0072] Taking Northwest China as an example, influenced by the collision of the Indian Plate and the Eurasian Plate, the tectonic stress field acts from south to north, resulting in intense tectonic activity. The northern, eastern, and western margins of the sedimentary basin are classified as Class I metallogenic blocks; the central region of the basin is classified as Class II metallogenic blocks; and the southern margin of the sedimentary basin is classified as Class III metallogenic blocks.

[0073] The tectonic activity intensity of the strike-slip zone is moderate, and the marginal area of ​​the sedimentary basin and the area in the central part of the sedimentary basin where volcanic activity has occurred since the Mesozoic and Cenozoic are divided into four types of metallogenic blocks.

[0074] Taking central and northern China as an example, the region is mainly affected by the closure of the Mongolia-Okhotsk Ocean, the collision of the western Indian Plate and the Eurasian Plate, and the subduction of the eastern Pacific Plate. The intensity of tectonic activity is moderate. The marginal areas of the sedimentary basins and the areas in the central part of the sedimentary basins where volcanic activity has occurred since the Mesozoic and Cenozoic eras are divided into four types of metallogenic blocks.

[0075] The tectonic activity in the tectonic extension zone is weak. If the tectonic stress field acts from the direction of boundary line A to the direction of boundary line B, the marginal area of ​​the sedimentary basin near boundary line A and the area in the middle of the sedimentary basin where volcanic activity has occurred since the Mesozoic and Cenozoic eras will be divided into five types of metallogenic blocks.

[0076] Taking Northeast China as an example, it is mainly affected by the subduction of the Pacific Plate, with weak tectonic activity. The tectonic stress field acts from east to west, dividing the eastern edge of the sedimentary basin and the central part of the sedimentary basin, where volcanic activity has occurred since the Mesozoic and Cenozoic, into five types of metallogenic blocks.

[0077] Step S3: Based on the characteristics of the proven sandstone-type uranium deposits and their spatiotemporal relationship with the metallogenic tectonic units, determine the type of metallogenic tectonic unit and the favorable metallogenic tectonic units.

[0078] Based on the characteristics of proven sandstone-type uranium deposits and their spatiotemporal relationship with tectonic units, the metallogenic tectonic units are divided into basement-exposed tectonic unit combinations and deep fluid-supplying tectonic units.

[0079] The basement-exposed structural unit combination includes structural unit A and structural unit B. Structural unit B is adjacent to structural unit A, which is a relatively uplifted and bedrock exposed. Structural unit B is a favorable mineralization structural unit. The basement-exposed structural unit combination is characterized by a relatively uplifted and bedrock exposed, which can provide gravitational potential energy and uranium source for surface uranium-bearing fluid runoff for uranium mineralization.

[0080] In deep fluid-supplying structural units, deep oil and gas and / or thermal fluids participate in uranium mineralization. Deep oil and gas provide a reducing medium for uranium mineralization, while thermal fluids can alter the environment of the target strata, promoting the redistribution of uranium within the formation. Deep fluid-supplying structural units include hydrocarbon accumulation structural units and magmatic-hydrothermal intrusion structural units, which are considered favorable mineralization structural units.

[0081] Step S4: Based on the ability of each metallogenic block to produce different types of metallogenic structural units, quickly delineate the metallogenic structural units.

[0082] Specifically, based on the ability of each metallogenic block to produce the combination of basement exposed structural units and the deep fluid supply structural units, metallogenic structural units are quickly delineated.

[0083] Among them, the ability of Class I, Class II, Class III, Class IV and Class V metallogenic blocks to produce basement outcrop tectonic unit combinations decreases in that order.

[0084] The ability of Class I, Class II, Class III, Class IV and Class V metallogenic blocks to produce deep fluid-supplying tectonic units increases sequentially.

[0085] Step S5: Analyze the delineated metallogenic structural units to determine the types of first-order favorable metallogenic structural units.

[0086] For basement-exposed structural unit assemblages, the lithological characteristics of the exposed bedrock in structural unit A are analyzed. Based on these characteristics, the types of first-order favorable mineralization structural units are determined, including:

[0087] If the bedrock exposed in structural unit A is intermediate volcanic rock, acidic volcanic rock, or granite, and intermediate volcanic rock, acidic volcanic rock, or granite can provide abundant uranium sources for uranium mineralization, then structural unit B is classified as a type of favorable mineralization structural unit.

[0088] If the bedrock exposed in tectonic unit A is metamorphic rock or basic volcanic rock, then tectonic unit B is classified into two types of favorable mineralization tectonic units.

[0089] The lithological characteristics of the bedrock exposed in the analytical structural unit A include:

[0090] Step S51: Obtain magnetic survey data of the bedrock outcrop area of ​​the target sedimentary basin, and perform geological interpretation of the magnetic survey data to determine the spatial distribution of rock lithology. This includes:

[0091] Magnetic data of the exposed bedrock areas in the target sedimentary basin were acquired, and the data were corrected and anomaly separated to distinguish between regional and local fields. The regional field refers to the large-scale bedrock mass, while the local field refers to the shallow bedrock mass. Based on a regional rock magnetic susceptibility database, the spatial distribution of rock lithology was inferred through anomaly amplitude, morphology, and gradient characteristics. Generally, basalt exhibits high magnetic characteristics, granite exhibits medium to low magnetic characteristics, and sedimentary rocks exhibit weak magnetic characteristics. High magnetic anomalies indicate basic rocks, while banded anomalies reflect faults or metamorphic rocks.

[0092] The main rocks exposed in the basement include volcanic rocks, granites, and metamorphic rocks. The volcanic rocks include basic volcanic rocks, intermediate volcanic rocks, and acidic volcanic rocks. Representative basic volcanic rocks include basalt, representative intermediate volcanic rocks include andesite, representative acidic volcanic rocks include rhyolite, and representative metamorphic rocks include gneiss.

[0093] The magnetic characteristics of the main rocks exposed in the basement are as follows:

[0094] Basic volcanic rocks exhibit high magnetic anomalies, with ΔT magnetic anomalies > 200 nT;

[0095] Intermediate volcanic rocks exhibit moderate anomalies, with magnetic anomalies ranging from 100 nT to ΔT and from 200 nT to 100 nT.

[0096] Acidic volcanic rocks exhibit low magnetic anomalies ΔT < 100 nT.

[0097] Basaltic lava flows often exhibit continuous, banded high anomalies, while volcanic clastic rocks show mottled anomalies due to variations in magnetite content, and the magnetic anomaly amplitude of altered volcanic rocks decreases significantly.

[0098] Granites exhibit low to moderate magnetic anomalies, but magnetite-bearing granites may show localized high anomalies.

[0099] The magnetic anomaly of metamorphic rocks depends on the composition of the protolith; when metamorphic rocks contain iron-magnesium minerals, the magnetic anomaly is higher.

[0100] Step S52: Conduct field outcrop surveys of the bedrock outcrop area to determine the lithology of the bedrock exposed in tectonic unit A.

[0101] Based on the spatial distribution of rock lithology determined by magnetic survey data, field verification was conducted, investigating outcrops in bedrock exposure areas. Detailed rock lithology identification and sedimentary structure observation were carried out on these outcrops to determine their lithology. The accuracy of magnetic survey data interpretation was verified, and the lithology identification results of the magnetic survey data were calibrated to further determine the spatial distribution of rock lithology.

[0102] In one embodiment, after determining the type of primary favorable mineralized tectonic unit, the uranium supply capacity of the exposed bedrock of tectonic unit A is analyzed, and the type of secondary favorable mineralized tectonic unit is determined based on the uranium supply capacity of the exposed bedrock of tectonic unit A.

[0103] Tectonic unit A, where the bedrock is exposed, is at a higher elevation and is more susceptible to weathering and erosion, thus serving as an erosion source area. This erosion source area provides uranium and material sources for uranium mineralization in tectonic unit B.

[0104] Rock samples of different lithologies were collected from the bedrock outcrop area, and the samples were analyzed to calculate the chemical weathering index and the average Th / U value.

[0105] Specifically, the calculation of the chemical weathering index includes:

[0106] Rock samples of different lithologies were collected from the bedrock outcrop area. Fifteen samples of each lithology were selected and divided into two groups. One group was used to test the content of major elements, and the other group was used to test the content of uranium (U) and thorium (Th). The rock samples were ground into 200-mesh powder, and the content of major elements was tested. The chemical weathering index was then calculated using the formula: CIA = {n(Al2O3) / [n(Al2O3)+n(CaO*)+n(Na2O)+n(K2O)}*100.

[0107] Wherein, CIA represents the chemical weathering index, n(Al2O3) represents the mole fraction of Al2O3 in the rock, n(CaO*) represents the mole fraction of CaO in the silicate (excluding the CaO portion from chemical deposition), n(Na2O) represents the mole fraction of Na2O in the rock, and n(K2O) represents the mole fraction of K2O in the rock.

[0108] If the chemical weathering index (CIA) value is greater than 0.8 and less than or equal to 1, it indicates that the exposed bedrock has undergone strong chemical weathering, which is conducive to uranium leaching and can provide abundant uranium sources for uranium mineralization.

[0109] If the chemical weathering index (CIA) is greater than 0.6 and less than or equal to 0.8, it indicates that the exposed bedrock has undergone moderate chemical weathering, and some uranium may be leached out, which can provide a considerable uranium source for uranium mineralization.

[0110] If the Chemical Weathering Index (CIA) value is greater than 0.5 and less than or equal to 0.6, it indicates that the exposed bedrock has undergone weak chemical weathering, and the leaching of uranium is relatively small, but it can still provide the uranium source required for uranium mineralization.

[0111] Methods for analyzing the uranium (U) and thorium (Th) content in rocks include:

[0112] Sample pretreatment: The sample is crushed and ground into powder, usually to a fineness of 200 mesh or less, to ensure the homogeneity of the sample.

[0113] Acid digestion: Uranium and thorium are commonly found in sparingly soluble minerals, requiring acid digestion to dissolve these minerals and release the uranium and thorium. Rock samples are digested using a mixture of concentrated nitric acid (HNO3), hydrochloric acid (HCl), and hydrofluoric acid (HF). After acid digestion, the solution is diluted with deionized water and further prepared for analysis.

[0114] The content of uranium and thorium was determined by inductively coupled plasma mass spectrometry (ICP-MS): the mass-to-charge ratio of the ions was measured in a mass spectrometer after the sample solution was ionized.

[0115] Data processing: Based on the analytical instrument results, combined with sample quality and standard samples, calculate the uranium (U) and thorium (Th) content. Calculate the Th / U ratio and obtain the average Th / U ratio.

[0116] If the average Th / U value is greater than 10, it indicates that the leaching of uranium in the exposed bedrock is significant and can provide abundant uranium sources for uranium mineralization.

[0117] If the average Th / U value is greater than 7 and less than or equal to 10, it indicates that there is significant uranium leaching in the exposed bedrock, which can provide a considerable uranium source for uranium mineralization.

[0118] If the average Th / U value is greater than 4 and less than or equal to 7, it indicates that the degree of uranium leaching in the exposed bedrock is not high, but it can still provide the uranium source required for uranium mineralization.

[0119] In one embodiment, the type of a secondary favorable mineralization tectonic unit is determined based on the chemical weathering index and the average Th / U value, combined with the uranium supply capacity of the bedrock exposed in tectonic unit A.

[0120] If the bedrock chemical weathering index (CIA) of the exposed tectonic unit A adjacent to a type of favorable metallogenic tectonic unit is greater than 0.6 and the average Th / U value is greater than 7, then the type of favorable metallogenic tectonic unit is identified as a key prospecting tectonic unit.

[0121] If the bedrock chemical weathering index (CIA) of the exposed bedrock of a type of favorable metallogenic structural unit A is greater than 0.6 or the average Th / U value is greater than 7, then the type of favorable metallogenic structural unit is identified as a key prospecting structural unit.

[0122] If the chemical weathering index (CIA) of the bedrock exposed in structural unit A adjacent to a type of favorable metallogenic structural unit is less than 0.6 and the average Th / U value is less than 7, then the type of favorable metallogenic structural unit is identified as a general prospecting structural unit.

[0123] If the bedrock chemical weathering index (CIA) of the exposed bedrock of the adjacent tectonic unit A of the second type of favorable metallogenic tectonic unit is greater than 0.6 and the average Th / U value is greater than 7, then the second type of favorable metallogenic tectonic unit is identified as a key prospecting tectonic unit.

[0124] If the bedrock chemical weathering index (CIA) of the exposed bedrock of the adjacent tectonic unit A of type II favorable metallogenic tectonic unit is greater than 0.6 or the average Th / U value is greater than 7, then the type II favorable metallogenic tectonic unit is determined to be a general prospecting tectonic unit.

[0125] For deep fluid-supplying structural units, the target mineral layers themselves generally lack organic matter and require the supply of deep oil and gas and / or thermal fluids. Therefore, uranium deposits often occur near the boundaries of structural units where oil and gas escape and / or thermal fluid activity occur.

[0126] The properties of the target mineral exploration layer have regional characteristics across the entire basin. The lithology and color characteristics of the target mineral exploration layer can be analyzed by collecting basin stratigraphic and borehole data.

[0127] If the target mineral layer is rich in evaporite minerals such as halite, potash, and gypsum, or is aeolian sandstone or red bed, then the target mineral layer is judged to be extremely lacking in organic matter.

[0128] If the target mineral layer has rocks that are red and gray in color, and the sandstone is mostly red and yellow, then the target mineral layer is considered to be relatively lacking in organic matter.

[0129] Collect structural data of the target basin and obtain a spatial distribution map of structural units in the target basin.

[0130] Collect oil and gas geological data of the target basin and obtain a spatial distribution map of oil and gas in the target basin;

[0131] By comparing the two above, the hydrocarbon accumulation structural unit is determined to be a favorable mineralization structural unit.

[0132] The surface fluids originate from the basin margins and flow into the interior of the target basin, reaching the boundaries of hydrocarbon accumulation tectonic units in the basin margin region. At these boundaries, hydrocarbons may escape, providing a reducing medium for uranium accumulation and mineralization. Therefore, by measuring the hydrocarbon gases in the soil at these boundaries, the types of first-order favorable mineralization tectonic units can be determined.

[0133] Soil hydrocarbon gas measurements include:

[0134] (1) Sampling Design

[0135] Grid layout: Increase the number of sampling points near the boundaries of hydrocarbon accumulation tectonic units in the basin margin area, and design survey lines in combination with the regional tectonic trend. The survey lines are designed perpendicular to the boundary lines of the tectonic units.

[0136] Sampling depth: Usually 1.5-3m is selected to avoid disturbance from surface biological activity; in special cases, the groundwater layer should be avoided to prevent gas dissolution and loss.

[0137] Pollution avoidance measures: Keep away from highways, farmland and industrial areas, and use inert material containers when sampling to avoid gas oxidation or adsorption.

[0138] (2) Gas Collection and Processing

[0139] Soil gas is extracted using a vacuum pump, and after moisture is removed by a drying tube, it is stored in a gas bag or glass bottle (the drying tube is made of silica gel).

[0140] (3) Hydrocarbon gas content analysis

[0141] Trace hydrocarbons can be rapidly detected on-site using a laser spectrometer, specifically a TDLAS.

[0142] By measuring hydrocarbon gases in the soil, the types of primary favorable metallogenic tectonic units are determined, specifically including:

[0143] If the hydrocarbon gas content at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region is measured to be greater than or equal to three times the background value of the region, it indicates that there is significant hydrocarbon escape at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region, which can provide a considerable reducing medium for uranium mineralization. In this case, the hydrocarbon accumulation tectonic unit is identified as a favorable mineralization tectonic unit of type A1.

[0144] If the hydrocarbon gas content at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region is measured to be greater than 1 times the background value of the region but less than or equal to 2 times the background value of the region, it indicates that there is a certain amount of hydrocarbon escape at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region, which can provide a certain amount of reducing medium for uranium mineralization. In this case, the hydrocarbon accumulation tectonic unit is identified as a B1 type favorable mineralization tectonic unit.

[0145] If the hydrocarbon gas content at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region is found to be comparable to the background value of the region, it indicates that there is no obvious hydrocarbon escape at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region, and it cannot provide a certain amount of reducing medium for uranium mineralization. In this case, the hydrocarbon accumulation tectonic unit is identified as a C1 type favorable mineralization tectonic unit.

[0146] In addition, deep fluid supply type tectonic units also include magmatic hydrothermal intrusion tectonic units, which are favorable mineralization tectonic units. For magmatic hydrothermal intrusion tectonic units, if there is intrusion of deep thermal fluids at the boundary of the magmatic hydrothermal intrusion tectonic unit, it indicates that there may be superimposed thermal fluids that transform the area into mineralization. Therefore, by measuring the helium at the boundary of the magmatic hydrothermal intrusion tectonic unit and analyzing the 3He / He ratio, we can explore whether there is deep thermal fluid intrusion into the shallow strata and determine the type of first-order favorable mineralization tectonic unit.

[0147] Soil helium measurements include:

[0148] (1) Sample collection

[0149] Grid layout: Sampling points are densified near the boundary of magmatic hydrothermal intrusion tectonic units where deep thermal fluid intrusion exists. Survey lines are designed in conjunction with the regional tectonic trend, and the survey lines are designed perpendicular to the boundary line of the tectonic unit.

[0150] Soil helium measurement: 1-3m depth, avoiding the groundwater layer to prevent dissolution loss.

[0151] Sampling equipment:

[0152] Stainless steel sampling probe + vacuum bottle, the vacuum bottle being pre-evacuated to 10... -3 mbar.

[0153] (2) Laboratory Analysis

[0154] The 3He / He ratio was determined with high precision using a Noblesse rare gas mass spectrometer.

[0155] (3) Data processing

[0156] calculate 3 The He / He ratio, expressed in Ra units, where Ra is the atmospheric ratio, is approximately 1.4 × 10⁻⁶.-6 .

[0157] like 3 He enrichment, 3 The He / He ratio is greater than or equal to 6Ra, that is... 3 A high He / He ratio indicates the presence of mantle-derived fluids, thus classifying the magmatic hydrothermal intrusion tectonic unit as a favorable A2-type mineralization tectonic unit. Among these, a typical... 3 The He / He ratio range is 6Ra≤ 3 He / He≤9Ra.

[0158] like 3 If the He / He ratio is greater than or equal to 0.1Ra and less than 6Ra, it indicates the presence of a supply of mixed fluids from the mantle and crust, and the magmatic hydrothermal intrusion tectonic unit is then classified as a favorable mineralization tectonic unit of type B2.

[0159] If He is the main character 3 If the He / He ratio is less than 0.1Ra, it indicates the supply of crustal fluids, and the magmatic hydrothermal intrusion tectonic unit is classified as a C2 type favorable mineralization tectonic unit.

[0160] The presence of oil and gas escape and superposition of thermal fluids is conducive to uranium mineralization. Therefore, the types of secondary favorable metallogenic structural units can be determined based on the superposition of primary favorable metallogenic structural units.

[0161] The superimposed structural unit of favorable mineral-forming structural units of type A1 and type A2 is identified as the key prospecting structural unit.

[0162] Superimposed structural units of favorable mineral-forming structural units of type A1 and type B2, or superimposed structural units of favorable mineral-forming structural units of type A2 and type B1, are identified as key prospecting structural units.

[0163] Superimposed structural units of type A1 and type C2 favorable mineral-forming structural units, or superimposed structural units of type A2 and type C1 favorable mineral-forming structural units, or superimposed structural units of type B1 and type B2 favorable mineral-forming structural units, are identified as general mineral exploration structural units.

[0164] This application conducts a macroscopic classification of sandstone-type uranium mineralization blocks based on the direction of regional tectonic stress fields and the intensity of tectonic activity. Based on the proven mineralization characteristics of sandstone-type uranium deposits and their spatiotemporal coupling relationship with tectonic units, favorable mineralization tectonic units are divided into two categories: basement-outcrop type and deep fluid-supply type. For basement-outcrop type tectonic units, the lithological characteristics of the bedrock are systematically analyzed through comprehensive interpretation of aeromagnetic data and field outcrop surveys. Chemical weathering index (CIA) and Th / U ratio tests are conducted on outcrop profiles to achieve subclassification and hierarchical evaluation of dominant tectonic units. For deep fluid-supply type tectonic units, the organic matter content of target strata and the identification of hydrocarbon accumulation tectonic units are first completed through geological data analysis. Based on this, soil hydrocarbon gas and soil helium measurements are conducted along the boundaries of hydrocarbon accumulation tectonic units to effectively capture hydrocarbon escape and deep thermal fluid activity signals, ultimately establishing a mineralization potential evaluation system for deep fluid-supply type tectonic units. This application utilizes the significant control effect of tectonic unit boundaries on the mineralization of sandstone-type uranium deposits, systematically evaluates the mineralization potential of sandstone-type uranium deposits in different tectonic units, and identifies tectonic units with mineralization advantages. This can provide scientific guidance for the determination of prospective areas for sandstone-type uranium deposits and open up new directions for promoting uranium exploration practices.

[0165] The above description is merely a specific embodiment of this application. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the protection scope of this application. The protection scope of this application should be determined by the protection scope of the claims.

Claims

1. A method for determining the potential for sandstone-type uranium deposits within a tectonic unit, characterized in that, The method includes: The tectonic activity characteristics of the sedimentary basin area are obtained, and the area is divided into tectonic compression zone, tectonic extension zone, and tectonic strike-slip zone based on the tectonic activity characteristics. Analyze the direction of tectonic stress fields and / or the intensity of tectonic activity in the tectonic compression zone, tectonic extension zone, and tectonic strike-slip zone, and determine the type of ore-forming block for sandstone-type uranium deposits based on the direction of tectonic stress fields and / or the intensity of tectonic activity. Based on the characteristics of proven sandstone-type uranium deposits and their spatiotemporal relationship with metallogenic tectonic units, the types of metallogenic tectonic units and favorable metallogenic tectonic units are determined. Based on the ability of each metallogenic block to produce different types of metallogenic tectonic units, quickly delineate the metallogenic tectonic units; The delineated metallogenic tectonic units were analyzed to determine the types of first-order favorable metallogenic tectonic units.

2. The method according to claim 1, characterized in that, Analyze the direction of tectonic stress fields and / or the intensity of tectonic activity in the tectonic compression zone, tectonic extension zone, and tectonic strike-slip zone. Based on the direction of tectonic stress fields and / or the intensity of tectonic activity, determine the type of metallogenic block for sandstone-type uranium deposits, including: The boundary lines of the sedimentary basin are divided into boundary lines A, C, B, and D in sequence. Boundary lines A and B are opposite each other, and boundary lines C and D are opposite each other. The area less than or equal to 50 km from the boundary line into the basin is called the marginal area, and the area greater than 50 km from the boundary line into the basin is called the central area of ​​the basin. The tectonic compression zone is highly tectonic. If the tectonic stress field acts from boundary line A to boundary line B, the edge areas of the sedimentary basin near boundary line B, the edge areas near boundary line C, and the edge areas near boundary line D are classified as Class I metallogenic blocks; the central area of ​​the basin is classified as Class II metallogenic blocks; and the edge areas of the sedimentary basin near boundary line B are classified as Class III metallogenic blocks. The tectonic activity intensity of the strike-slip zone is moderate. The marginal area of ​​the sedimentary basin and the area in the middle of the sedimentary basin where volcanic activity has occurred since the Mesozoic and Cenozoic are divided into four types of metallogenic blocks. The tectonic activity in the tectonic extension zone is weak. If the tectonic stress field acts from the direction of boundary line A to the direction of boundary line B, the marginal area of ​​the sedimentary basin near boundary line A and the area in the middle of the sedimentary basin where volcanic activity has occurred since the Mesozoic and Cenozoic eras will be divided into five types of metallogenic blocks.

3. The method according to claim 1, characterized in that, The determination of tectonic unit types and favorable metallogenic tectonic units based on the proven characteristics of sandstone-type uranium deposits and their spatiotemporal relationship with tectonic units includes: The mineralization tectonic units are divided into basement-exposed tectonic unit assemblages and deep fluid-supplying tectonic units. The basement-exposed tectonic unit assemblages include tectonic unit A and tectonic unit B, where tectonic unit B is adjacent to a relatively uplifted tectonic unit A with exposed bedrock, and tectonic unit B is a favorable mineralization tectonic unit. The deep fluid-supplying tectonic units include hydrocarbon accumulation tectonic units and magmatic-hydrothermal intrusion tectonic units, where hydrocarbon accumulation tectonic units and magmatic-hydrothermal intrusion tectonic units are favorable mineralization tectonic units.

4. The method according to claim 3, characterized in that, The capacity of each metallogenic block to produce different types of metallogenic tectonic units is as follows: The ability of Class I, Class II, Class III, Class IV and Class V metallogenic blocks to produce basement outcrop tectonic unit combinations decreases sequentially. The ability of Class I, Class II, Class III, Class IV and Class V metallogenic blocks to produce deep fluid-supplying tectonic units increases sequentially.

5. The method according to claim 4, characterized in that, The analysis of the delineated metallogenic tectonic units to determine the types of first-order favorable metallogenic tectonic units includes: For the basement-exposed structural unit combination, analyze the lithological characteristics of the exposed bedrock of structural unit A, and determine the first-order favorable metallogenic structural unit type based on the lithological characteristics of the exposed bedrock of structural unit A. For deep fluid-supply type tectonic units, the type of first-order favorable mineralization tectonic unit is determined by measuring the soil hydrocarbon gas at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region and measuring the helium gas at the boundary of the hydrocarbon accumulation tectonic unit.

6. The method according to claim 5, characterized in that, For the basement-exposed structural unit assemblage, the lithological characteristics of the exposed bedrock in structural unit A are analyzed. Based on these characteristics, first-order favorable mineralization structural unit types are classified, including: If the bedrock exposed in tectonic unit A is intermediate volcanic rock, acidic volcanic rock, or granite, then tectonic unit B is classified as a type of favorable mineralization tectonic unit. If the bedrock exposed in tectonic unit A is metamorphic rock or basic volcanic rock, then tectonic unit B is classified into two types of favorable mineralization tectonic units.

7. The method according to claim 5 or 6, characterized in that, After analyzing the lithological characteristics of the bedrock exposed in structural unit A, and determining the type of first-order favorable mineralized structural unit based on these characteristics, the process further includes: The uranium supply capacity of the exposed bedrock in structural unit A is analyzed, and the type of secondary favorable mineralization structural unit is determined based on the uranium supply capacity of the exposed bedrock in structural unit A.

8. The method according to claim 7, characterized in that, The uranium supply capacity of the exposed bedrock in the analytical structural unit A is used to determine the types of secondary favorable mineralization structural units, including: Tectonic unit A, where the bedrock is exposed, is designated as the erosion source area; Rock samples of different lithologies were collected from the bedrock outcrop area, and the samples were analyzed to calculate the chemical weathering index and the average Th / U value. Based on the chemical weathering index and average Th / U value, the uranium supply capacity of the exposed bedrock in tectonic unit A is analyzed. Based on the chemical weathering index and average Th / U value, combined with the analysis results of the uranium supply capacity of the exposed bedrock of tectonic unit A, the type of secondary favorable mineralization tectonic unit is determined.

9. The method according to claim 8, characterized in that, The analysis of the uranium supply capacity of the exposed bedrock in tectonic unit A based on the chemical weathering index and average Th / U value includes: If the chemical weathering index (CIA) value is greater than 0.8 and less than or equal to 1, it indicates that the exposed bedrock has undergone strong chemical weathering, which is conducive to uranium leaching and can provide abundant uranium sources for uranium mineralization. If the chemical weathering index (CIA) is greater than 0.6 and less than or equal to 0.8, it indicates that the exposed bedrock has undergone moderate chemical weathering, and some uranium may be leached out, which can provide a considerable uranium source for uranium mineralization. If the chemical weathering index (CIA) is greater than 0.5 and less than or equal to 0.6, it indicates that the exposed bedrock has undergone weak chemical weathering, and the leaching of uranium is relatively small, but it can still provide the uranium source required for uranium mineralization. If the average Th / U value is greater than 10, it indicates that the leaching of uranium in the exposed bedrock is significant and can provide abundant uranium sources for uranium mineralization. If the average Th / U value is greater than 7 and less than or equal to 10, it indicates that there is significant uranium leaching in the exposed bedrock, which can provide a considerable uranium source for uranium mineralization. If the average Th / U value is greater than 4 and less than or equal to 7, it indicates that the degree of uranium leaching in the exposed bedrock is not high, but it can still provide the uranium source required for uranium mineralization.

10. The method according to claim 9, characterized in that, Based on the chemical weathering index and average Th / U value, combined with the analysis results of the uranium supply capacity of the exposed bedrock of tectonic unit A, the types of secondary favorable mineralization tectonic units are determined, including: If the bedrock chemical weathering index (CIA) of the exposed tectonic unit A adjacent to a type of favorable metallogenic tectonic unit is greater than 0.6 and the average Th / U value is greater than 7, then the type of favorable metallogenic tectonic unit is identified as a key prospecting tectonic unit. If the bedrock chemical weathering index (CIA) of the exposed bedrock of a type of favorable metallogenic structural unit A is greater than 0.6 or the average Th / U value is greater than 7, then the type of favorable metallogenic structural unit is identified as a key prospecting structural unit. If the chemical weathering index (CIA) of the bedrock exposed in structural unit A adjacent to a type of favorable metallogenic structural unit is less than 0.6 and the average Th / U value is less than 7, then the type of favorable metallogenic structural unit is identified as a general prospecting structural unit. If the bedrock chemical weathering index (CIA) of the exposed bedrock of the adjacent tectonic unit A of the second type of favorable metallogenic tectonic unit is greater than 0.6 and the average Th / U value is greater than 7, then the second type of favorable metallogenic tectonic unit is identified as a key prospecting tectonic unit. If the bedrock chemical weathering index (CIA) of the exposed bedrock of the adjacent tectonic unit A of type II favorable metallogenic tectonic unit is greater than 0.6 or the average Th / U value is greater than 7, then the type II favorable metallogenic tectonic unit is determined to be a general prospecting tectonic unit.

11. The method according to claim 5, characterized in that, For deep fluid-supply type structural units, the types of first-order favorable mineralization structural units are determined by measuring soil hydrocarbon gases at the boundaries of hydrocarbon accumulation structural units in the basin margin region and measuring helium gases at the boundaries of hydrocarbon accumulation structural units, including: Measuring soil hydrocarbon gases at the boundaries of hydrocarbon accumulation tectonic units in the basin margin region to determine the types of first-order favorable mineralization tectonic units: If the hydrocarbon gas content at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region is measured to be greater than or equal to three times the background value of the region, then the hydrocarbon accumulation tectonic unit is identified as a favorable mineralization tectonic unit of type A1. If the hydrocarbon gas content at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region is measured to be greater than 1 times the background value of the region and less than or equal to 2 times the background value of the region, then the hydrocarbon accumulation tectonic unit is identified as a B1 type favorable mineralization tectonic unit. If the hydrocarbon gas content at the boundary of the hydrocarbon accumulation tectonic unit in the basin margin region is found to be comparable to the background value of the region, then the hydrocarbon accumulation tectonic unit is identified as a C1 type favorable mineralization tectonic unit. Measure the helium gas at the boundary of the magmatic hydrothermal intrusion tectonic unit and calculate 3 He / 4 The He ratio determines the type of primary favorable metallogenic tectonic unit: like 3 He / 4 If the He ratio is greater than or equal to 6Ra, the magmatic hydrothermal intrusion tectonic unit is classified as a favorable mineralization tectonic unit of type A2. like 3 He / 4 If the He ratio is greater than or equal to 0.1Ra and less than or between 6Ra, the magmatic hydrothermal intrusion tectonic unit is classified as a B2 type favorable mineralization tectonic unit. like 3 He / 4 If the He ratio is less than 0.1Ra, the magmatic hydrothermal intrusion tectonic unit is classified as a C2 type favorable mineralization tectonic unit.

12. The method according to claim 10, characterized in that, For deep fluid-supply type structural units, the type of first-order favorable mineralization structural unit is determined by measuring soil hydrocarbon gases at the boundary of hydrocarbon accumulation structural units near the basin edge and measuring helium gases at the boundary of hydrocarbon accumulation structural units. After determining the type of first-order favorable mineralization structural unit, the method further includes: Based on the superposition of primary favorable metallogenic tectonic units, the types of secondary favorable metallogenic tectonic units are determined.

13. The method according to claim 12, characterized in that, The determination of the type of secondary favorable metallogenic tectonic unit based on the superposition of primary favorable metallogenic tectonic units includes: The superimposed structural unit of favorable metallogenic structural units of type A1 and type A2 is identified as the key prospecting structural unit; The superimposed structural units of favorable metallogenic structural units of type A1 and type B2, or the superimposed structural units of favorable metallogenic structural units of type A2 and type B1, are identified as key prospecting structural units. Superimposed structural units of type A1 and type C2 favorable mineral-forming structural units, or superimposed structural units of type A2 and type C1 favorable mineral-forming structural units, or superimposed structural units of type B1 and type B2 favorable mineral-forming structural units, are identified as general mineral exploration structural units.

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