A three-dimensional fine modeling method for alkaline granite-type uranium deposits

Abstract

The present invention belongs to the field of uranium geological exploration, and specifically discloses a three-dimensional fine modeling method for alkaline granite uranium deposits, including: step (1): relying on topographic survey, constructing a surface elevation module; step (2): clarifying the ore body control factors, and constructing an ore body fault module; step (3): based on AMT cross-section depth measurement, constructing a rock body contour module; step (4): based on surface survey and drilling engineering, constructing a lithology module; step (5): carrying out well logging and interpreting the results, constructing a uranium ore body module; step (6): embedding the modules constructed by steps (1)-(5), and comprehensively constructing a three-dimensional model of the ore deposit. The method of the present invention combines the advantages of geology, topography, geophysics, deep engineering, radioactive logging, etc., to achieve modular and refined construction of three-dimensional modeling of alkaline granite uranium deposits.

Description

Technical Field

[0001] The invention belongs to the field of uranium geological exploration, and in particular relates to a three-dimensional fine modeling method for an alkaline granite-type uranium deposit. Background Art

[0002] The construction of ore deposit models is an important part of geological exploration activities. Its visualization characteristics play an important guiding role in guiding the deployment of further exploration work. Different types of ore deposits have different geological characteristics, and the parameters and modeling steps required in the modeling process are also different. Alkaline granite-type uranium deposits are one of the important uranium resource types in the world. However, due to the constraints of dressing technology and other reasons, the research on this type of uranium deposits in my country is still relatively weak. There are few studies on the three-dimensional fine modeling methods for alkaline granite-type uranium deposits.

[0003] In addition, the existing ore deposit modeling methods are generally "cube block" type three-dimensional modeling, which can only highlight the core body, and the real boundary and other characteristics of the ore deposit are often based on reasonable speculation. Moreover, it is an overall modeling and has not achieved modularization. Realizing modular three-dimensional fine modeling of ore deposits is an important development direction in the field of ore deposit modeling.

[0004] Therefore, it is urgent to develop a three-dimensional fine modeling method for alkaline granite-type uranium deposits. Summary of the invention

[0005] The purpose of the present invention is to provide a three-dimensional fine modeling method for alkaline granite-type uranium deposits. The method combines the advantages of geology, topography, geophysics, deep engineering, radioactive logging, etc. to achieve modular and refined construction of three-dimensional modeling of alkaline granite-type uranium deposits, which has important guiding significance for guiding further exploration or resource estimation of alkaline granite-type uranium deposits.

[0006] The technical solution to achieve the purpose of the present invention is:

[0007] A three-dimensional fine modeling method for alkaline granite-type uranium deposits, the method comprising the following steps:

[0008] Step (1): Based on topographic survey, construct a surface elevation module;

[0009] Step (2): clarify the ore body control factors and construct the ore body fault module;

[0010] Step (3): construct a rock mass contour module based on AMT cross-section depth measurement;

[0011] Step (4): constructing a lithology module based on surface survey and drilling engineering;

[0012] Step (5): Conduct well logging and interpret the results to construct a uranium ore body module;

[0013] Step (6): Integrate the modules constructed in steps (1)-(5) to comprehensively construct a three-dimensional model of the ore deposit.

[0014] The specific steps of step (1) are as follows: taking the ore deposit as the center, conducting topographic survey within the ore deposit; using RTK-GPS for on-site data collection and using CASS software for data processing; selecting GPS fitting elevation for elevation control measurement, and all coordinate records should maintain the same coordinate system; importing the collected data into ArcGIS software and generating a topographic map; importing the ArcGIS data file into MicroMine software to generate a surface elevation module.

[0015] In the step (1), the coordinate system selects the WGS-1984 geographic coordinate system UTM projection system.

[0016] The specific steps of step (2) are as follows: on the basis of fully collecting geological data of the study area, conducting geological survey and mapping work on the ore deposit, accurately drawing the position of the rock-controlling / ore-controlling faults on the geological map, and measuring or calculating the surface occurrence and deep occurrence of the boundary points; based on the above-mentioned rock-controlling / ore-controlling fault data including the surface occurrence and deep occurrence of the boundary points, generating a rock-controlling / ore-controlling fault module.

[0017] The calculation formula for the inclination angle of the deep occurrence in step (2) is:

[0018] α=arctan(H / L)

[0019] Where α is the inclination angle of the fault;

[0020] H is the vertical distance between the surface exposure point A and the deep engineering exposure point B;

[0021] L is the horizontal distance L between the surface exposure point A and the deep engineering exposure point B.

[0022] The inclination of the deep occurrence in step (2) is the horizontal projection direction of the line connecting the two deep engineering exposure points.

[0023] The specific steps of step (3) are as follows: along the strike direction of the rock mass / ore body and its vertical direction, several AMT sounding profiles are arranged in parallel and crosswise manner, and the profile length is greater than the scale of the rock mass / ore body; the measurement points are distributed at unequal intervals; with the deep engineering exposure data as a reference benchmark, the AMT sounding data is inverted and interpreted, the rock mass / ore body boundary on each sounding profile is circled, and the rock mass / ore body boundary is imported into the MicroMine software for automatic smooth splicing to form a rock mass contour module.

[0024] In the step (3), the distance between the measuring points is unequally spaced, with the point distance being 50 m at the center of the rock mass / ore body and being reduced to 25 m at the boundary of the rock mass / ore body.

[0025] The lithology module in step (4) comprises two units: a surface lithology unit and a deep lithology unit.

[0026] The surface lithology unit is based on the surface geological survey data of the ore deposit or the geological map of the ore deposit, and the three-dimensional coordinates of the lithology control points or boundary control points / lines are intensively extracted, and three-dimensional spatial projection is performed in the MicroMine software to establish the surface lithology unit.

[0027] The deep lithological unit relies on the lithological data of deep drilling projects to connect adjacent drilling work according to geological basis, first construct a planar two-dimensional horizontal exploration line profile, and then connect the two-dimensional horizontal exploration lines into a three-dimensional geological body in three-dimensional space according to geological basis; for the deep exploration projects at the edge, the lithological unit is infinitely extrapolated to 1 / 2 of the project spacing for preliminary processing.

[0028] The specific steps of step (5) are as follows: for alkaline granite-type uranium deposits, spectral logging is used, and the data types are U and Th count rates, to interpret the single-point uranium content and the ore layer uranium content; the uranium content of each single project and the depth data of the corresponding measuring point are imported into MicroMine software; and then according to the general principles of ore body delineation and connection, a two-dimensional ore body is first constructed according to the exploration line profile, and then the same ore bodies of different exploration line profiles are connected to construct a three-dimensional ore body module.

[0029] The interpretation calculation formula of the single point uranium content is:

[0030]

[0031] in, is the U content of each unit layer (×0.01% eU); is the U coefficient after correction of molten iron (CPS); is the Th coefficient after molten iron correction (CPS); S Uu is the sensitivity coefficient of U in the U window (cps / 0.01%eU); S Thu is the sensitivity coefficient of U in the Th window (cps / 0.01%eU); S Uth is the sensitivity coefficient of Th in the U window (cps / 0.01%eU); S Thth is the sensitivity coefficient of Th within the Th window (cps / 0.01%eU).

[0032] The interpretation and calculation formula of the uranium content of the ore layer is:

[0033]

[0034] Among them, Q U is the U content in the uranium ore layer (×0.01% eU); is the U content of each unit layer (×0.01% eU); h is the sampling interval; H is the thickness of the ore-bearing layer.

[0035] The step (6) comprises:

[0036] Step (6.1): Determine the three-dimensional scope of modeling, including the rectangular coordinates of each vertex (turning point) of the plane projection of the proposed model, and the depth data of the necessary units;

[0037] Step (6.2): ​​Import the surface elevation module constructed in step (1). From the elevation point of view, the surface elevation module will constrain all other modules;

[0038] Step (6.3): embedding the surface lithology module constructed in step (4) with the surface elevation module constructed in step (1), and subjecting it to the constraints of the surface elevation module constructed in step (1);

[0039] Step (6.3): importing the fault module constructed in step (2) and the rock mass contour module constructed in step (3), wherein the rock mass contour module constructed in step (3) is restricted by the fault module constructed in step (2);

[0040] Step (6.4): Import the lithology module constructed in step (4), subject to the constraints of all models in the above step (6.3);

[0041] Step (6.5): Import the uranium ore body model constructed in step (5), subject to the constraints of all models in the above step (6.4);

[0042] Step (6.6): After the above steps, carry out the decoration and finishing to complete the fine construction of the three-dimensional model of the alkaline granite-type uranium deposit.

[0043] The beneficial technical effects of the present invention are:

[0044] 1. The present invention proposes a modular three-dimensional fine modeling method for alkaline granite-type uranium deposits, which realizes the convenient modular assembly construction of different element units (sub-models) of the three-dimensional model of the deposit.

[0045] 2. The modular three-dimensional fine modeling method of alkaline granite-type uranium deposits proposed in the present invention clarifies the modular three-dimensional modeling process of alkaline granite-type uranium deposits and improves the modeling efficiency of this type of uranium deposits.

[0046] 3. The modular three-dimensional fine modeling method of alkaline granite-type uranium deposits proposed in the present invention combines the advantages of topography, geophysical exploration and radioactive elements on the basis of general geological modeling, greatly improving the fineness of the three-dimensional model. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1The three-dimensional model diagram of a certain alkaline granite-type uranium deposit constructed by the method of the present invention. DETAILED DESCRIPTION

[0048] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0049] The present invention provides a modular three-dimensional fine modeling method for alkaline granite-type uranium deposits, which specifically comprises the following steps:

[0050] Step (1): Based on topographic survey, construct a surface elevation module.

[0051] With the ore deposit as the center, topographic surveys are carried out within the ore deposit to provide basic data for the construction of the surface elevation module. The measurement accuracy is 1:2000, the data collection line distance is 20m, and the point distance is 5m. RTK-GPS is used for on-site collection, and CASS software is used for data processing. GPS fitting elevation is selected for elevation control measurement, and all coordinate records should maintain the same coordinate system. The collected data is imported into ArcGIS software and a topographic map is generated, with a contour interval of 2m and a resolution of 0.1m. The ArcGIS data file is imported into MicroMine software to generate a surface elevation module.

[0052] Preferably, the coordinate system preferably selects the WGS-1984 geographic coordinate system UTM projection.

[0053] Step (2): Identify the ore body control factors and construct the ore-controlling fault module.

[0054] On the basis of fully collecting geological data in the research area, geological survey and mapping work is carried out on the ore deposits. The accuracy of geological survey and mapping is 1:2000, and the controlling factors of the ore body are clarified and the controlling elements are determined. For alkaline granite-type uranium deposits, the controlling factors are generally related to the rock body and faults. The location of the rock-controlling / ore-controlling faults is accurately drawn on the geological map, and the surface occurrence of different boundary points is collected and recorded as much as possible.

[0055] For deep occurrence, the dip is calculated using the following formula:

[0056] α=arctan(H / L)

[0057] Where α is the dip angle of the fault;

[0058] H is the vertical distance between the surface exposure point A and the deep engineering exposure point B;

[0059] L is the horizontal distance L between the surface exposure point A and the deep engineering exposure point B.

[0060] For deep occurrence, its inclination is the horizontal projection direction of the line connecting two deep engineering exposure points.

[0061] The surface fault data including the surface occurrence and deep occurrence of the boundary points are imported into MicroMine software to generate a surface model of the ore-controlling fault. Based on the deep occurrence data of the fault, a rock-controlling / ore-controlling fault module is expanded.

[0062] Step (3): Based on the AMT cross-section depth measurement, a rock mass contour module is constructed.

[0063] The deep contour model of the ore deposit is a difficult point in the three-dimensional modeling of the ore deposit. The usual practice is to use deep exposure engineering to extrapolate a certain distance to determine it. According to the characteristics of the rock mass controlling the ore in alkaline granite-type uranium deposits, the method of geophysical depth detection can be used to accurately delineate the rock mass boundary. Audio magnetotelluric (AMT) is a commonly used method. Along the strike of the rock mass / ore body and its vertical direction, several AMT depth sounding profiles are arranged in parallel and crosswise, and the profile length is required to be greater than the scale of the rock mass / ore body. The spacing between measurement points can be distributed with unequal spacing. In the center of the rock mass / ore body, the point spacing can be 50m, and at the boundary of the rock mass / ore body, the point spacing is reduced to 25m.

[0064] Using the deep engineering exposure data as a reference, the AMT bathymetric data is inverted and interpreted, the rock mass / ore body boundary on each bathymetric profile is circled, and imported into the MicroMine software for automatic smooth stitching to form a rock mass contour module.

[0065] Step (4): Construct a lithology module based on surface survey and drilling engineering.

[0066] The lithology module contains two units: surface lithology unit and deep lithology unit. The surface lithology unit is based on the surface geological survey data of the deposit or the geological map of the deposit. The three-dimensional coordinates of the lithology control points or boundary control points / lines are densely extracted, and three-dimensional space projection is performed in the MicroMine software to establish the surface lithology unit. The deep rock model mainly relies on the lithology data of deep drilling engineering, connects the adjacent drilling work according to the geological basis, first constructs the plane two-dimensional horizontal exploration line profile, and then connects the two-dimensional horizontal exploration line into a three-dimensional geological body in three-dimensional space according to the geological basis.

[0067] It should be made clear that for deep exploration projects at the edge, the lithologic units are infinitely extrapolated to 1 / 2 of the project spacing for preliminary processing, but this does not represent the final boundary of the rock mass, which will be further constrained in step (6).

[0068] Step (5): Conduct well logging and interpret the results to construct a uranium ore body module.

[0069] For alkaline granite-type uranium deposits, which often have a high thorium content, energy spectrum logging is required. The logging data collection interval is 5cm, and the data type is U and Th count rate. The raw data is corrected and the single-point uranium content is interpreted according to the following formula:

[0070]

[0071] in, is the U content of each unit layer (×0.01% eU); is the U coefficient after correction of molten iron (CPS); is the Th coefficient after molten iron correction (CPS); S Uu is the sensitivity coefficient of U in the U window (cps / 0.01%eU); S Thu is the sensitivity coefficient of U in the Th window (cps / 0.01%eU); S Uth is the sensitivity coefficient of Th in the U window (cps / 0.01%eU); S Thth is the sensitivity coefficient of Th within the Th window (cps / 0.01%eU).

[0072] The U content of the ore-bearing layer is calculated according to the following formula:

[0073]

[0074] Among them, Q U is the U content in the uranium ore layer (×0.01% eU); is the U content of each unit layer (×0.01% eU); h is the sampling interval; H is the thickness of the ore-bearing layer.

[0075] The uranium content and corresponding measured depth data of each single project are imported into MicroMine software. Then, according to the general principles of ore body delineation and connection, a two-dimensional ore body is first constructed according to the exploration line profile, and then the same ore bodies in different exploration line profiles are connected to construct a three-dimensional ore body module.

[0076] Step (6): Integrate the modules constructed in steps (1)-(5) to comprehensively construct a three-dimensional model of the ore deposit.

[0077] The five modules from step (1) to step (5) are independent of each other, especially the boundary parts are mutually constrained, and need to be embedded in priority order. The specific embedding steps and principles are as follows:

[0078] Step (6.1): Determine the three-dimensional scope of modeling, including the rectangular coordinates of each vertex (turning point) of the plane projection of the proposed model, and the depth data of the necessary units;

[0079] Step (6.2): ​​Import the surface elevation module constructed in step (1). From the elevation point of view, the surface elevation module will constrain all other modules;

[0080] Step (6.3): embedding the surface lithology module constructed in step (4) with the surface elevation module constructed in step (1), and subjecting it to the constraints of the surface elevation module constructed in step (1);

[0081] Step (6.3): importing the fault module constructed in step (2) and the rock mass contour module constructed in step (3), wherein the rock mass contour module constructed in step (3) is restricted by the fault module constructed in step (2);

[0082] Step (6.4): Import the lithology module constructed in step (4), subject to the constraints of all models in the above step (6.3);

[0083] Step (6.5): Import the uranium ore body model constructed in step (5), subject to the constraints of all models in the above step (6.4);

[0084] Step (6.5): After the above steps, the decoration is carried out to complete the fine construction of the modular three-dimensional model of the alkaline granite-type uranium deposit;

[0085] The three-dimensional model of an alkaline granite-type uranium deposit constructed by this method is as follows: Figure 1 As shown, the three-dimensional model of the alkaline granite-type uranium deposit achieves a high degree of integration of topography, lithology, structure, and ore body. It not only fully displays various key geological elements, but also effectively restores the morphological characteristics and contact relationships of each element, which is as close to the objective geological facts of the deposit as possible and greatly improves the refinement of the three-dimensional model.

[0086] The present invention is described in detail above with reference to the accompanying drawings and embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present invention. The contents not described in detail in the present invention can adopt the existing technology.

Claims

1. A three-dimensional fine modeling method for alkaline granite-type uranium deposits, characterized in that: The method comprises the following steps: Step (1): Based on topographic survey, construct a surface elevation module; Step (2): clarify the ore body control factors and construct the ore body fault module; Step (3): construct a rock mass contour module based on AMT cross-section depth measurement; Step (4): constructing a lithology module based on surface survey and drilling engineering; Step (5): Conduct well logging and interpret the results to construct a uranium ore body module; Step (6): Integrate the modules constructed in steps (1) to (5) to comprehensively construct a three-dimensional model of the ore deposit; The specific step (5) is as follows: for alkaline granite-type uranium deposits, spectral logging is used, and the data types are U and Th count rates, to interpret the single-point uranium content and the ore layer uranium content; the uranium content of each single project and the corresponding measuring point depth data are imported into MicroMine software; and then according to the general principles of ore body delineation and connection, a two-dimensional ore body is first constructed according to the exploration line profile, and then the same ore bodies of different exploration line profiles are connected to construct a three-dimensional ore body module; The interpretation calculation formula of the single point uranium content is: in, is the U content of each unit layer; is the U coefficient after correction of molten iron; is the Th coefficient after correction by molten iron; S Uu is the sensitivity coefficient of U in the U window; S Thu is the sensitivity coefficient of U in the Th window; S Uth is the sensitivity coefficient of Th in the U window; S Thth is the sensitivity coefficient of Th in the Th window.

2. The three-dimensional fine modeling method of alkaline granite-type uranium deposit according to claim 1 is characterized in that: The specific steps of step (1) are as follows: taking the ore deposit as the center, conducting topographic survey within the ore deposit; using RTK-GPS for on-site data collection and using CASS software for data processing; selecting GPS fitting elevation for elevation control measurement, and all coordinate records should maintain the same coordinate system; importing the collected data into ArcGIS software and generating a topographic map; importing the ArcGIS data file into MicroMine software to generate a surface elevation module.

3. The three-dimensional fine modeling method of alkaline granite-type uranium deposit according to claim 2 is characterized in that: In the step (1), the coordinate system selects the WGS-1984 geographic coordinate system UTM projection system.

4. The three-dimensional fine modeling method of alkaline granite-type uranium deposit according to claim 1 is characterized in that: The specific steps of step (2) are as follows: on the basis of fully collecting geological data of the study area, conducting geological survey and mapping work on the ore deposit, accurately drawing the position of the rock-controlling / ore-controlling faults on the geological map, and measuring or calculating the surface and deep occurrences of the boundary points; based on the rock-controlling / ore-controlling fault data including the surface and deep occurrences of the boundary points, generating a rock-controlling / ore-controlling fault module.

5. A three-dimensional fine modeling method for alkaline granite-type uranium deposit according to claim 4, characterized in that: The calculation formula for the inclination angle of the deep occurrence in step (2) is: α=arctan(H / L) Where α is the inclination angle of the fault; H is the vertical distance between the surface exposure point A and the deep engineering exposure point B; L is the horizontal distance between the surface exposure point A and the deep engineering exposure point B.

6. A three-dimensional fine modeling method for alkaline granite-type uranium deposit according to claim 5, characterized in that: The inclination of the deep occurrence in step (2) is the horizontal projection direction of the line connecting the two deep engineering exposure points.

7. The three-dimensional fine modeling method of alkaline granite-type uranium deposit according to claim 1 is characterized in that: The specific steps of step (3) are as follows: along the strike direction of the rock mass / ore body and its vertical direction, several AMT sounding profiles are arranged in parallel and crosswise manner, and the profile length is greater than the scale of the rock mass / ore body; the measurement points are distributed at unequal intervals; with the deep engineering exposure data as a reference benchmark, the AMT sounding data is inverted and interpreted, the rock mass / ore body boundary on each sounding profile is circled, and the rock mass / ore body boundary is imported into the MicroMine software for automatic smooth splicing to form a rock mass contour module.

8. A three-dimensional fine modeling method for alkaline granite-type uranium deposit according to claim 7, characterized in that: In the step (3), the distance between the measuring points is unequally spaced, with the point distance being 50 m at the center of the rock mass / ore body and being reduced to 25 m at the boundary of the rock mass / ore body.

9. The three-dimensional fine modeling method of alkaline granite-type uranium deposit according to claim 7, characterized in that: The lithology module in step (4) comprises two units: a surface lithology unit and a deep lithology unit.

10. A three-dimensional fine modeling method for alkaline granite-type uranium deposit according to claim 9, characterized in that: The surface lithology unit is based on the surface geological survey data of the ore deposit or the geological map of the ore deposit, and the three-dimensional coordinates of the lithology control points or boundary control points / lines are intensively extracted, and three-dimensional spatial projection is performed in the MicroMine software to establish the surface lithology unit.

11. A three-dimensional fine modeling method for alkaline granite-type uranium deposit according to claim 9, characterized in that: The deep lithological unit relies on the lithological data of deep drilling projects to connect adjacent drilling work according to geological basis, first construct a planar two-dimensional horizontal exploration line profile, and then connect the two-dimensional horizontal exploration lines into a three-dimensional geological body in three-dimensional space according to geological basis; for the deep exploration projects at the edge, the lithological unit is infinitely extrapolated to 1 / 2 of the project spacing for preliminary processing.

12. The three-dimensional fine modeling method of alkaline granite-type uranium deposit according to claim 1, characterized in that: The interpretation calculation formula of the uranium content of the ore layer is: Among them, Q U is the U content in the uranium ore layer; is the U content of each unit layer; h is the sampling interval; H is the thickness of the mineral-bearing layer.

13. The three-dimensional fine modeling method of alkaline granite-type uranium deposit according to claim 1, characterized in that: The step (6) comprises: Step (6.1): Determine the three-dimensional scope of modeling, including the rectangular coordinates of the vertices and turning points of the plane projection of the proposed model; Step (6.2): ​​Import the surface elevation module constructed in step (1). From the elevation point of view, the surface elevation module will constrain all other modules; Step (6.3): embedding the surface lithology module constructed in step (4) with the surface elevation module constructed in step (1), and subjecting it to the constraints of the surface elevation module constructed in step (1); Step (6.3): importing the fault module constructed in step (2) and the rock mass contour module constructed in step (3), wherein the rock mass contour module constructed in step (3) is restricted by the fault module constructed in step (2); Step (6.4): Import the lithology module constructed in step (4), subject to the constraints of all models in the above step (6.3); Step (6.5): Import the uranium ore body model constructed in step (5), subject to the constraints of all models in the above step (6.4); Step (6.6): After the above steps, carry out the decoration and finishing to complete the fine construction of the three-dimensional model of the alkaline granite-type uranium deposit.

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