A method of exploring a thin vein deposit by drilling instead of trenching

Abstract

A thin vein deposit is explored by drilling instead of pit exploration, based on the accumulated geological data in the existing known mine exploration and mining process, and the existing mine space data, a computer is used to build a full data three-dimensional geological model and a roadway space model; the computer analyzes the geological conditions of the metallogenic regularity based on the full data three-dimensional geological model; based on the full data three-dimensional geological model and the roadway space model, drilling construction in the pit is designed; the advantages of shallow drilling depth and low cost are used in the pit, which reduces the cost of resource exploration, prolongs the life of old mine and increases the recoverable resource reserves.

Description

Technical Field

[0001] This invention relates to the field of metal deposit exploration technology, specifically to a method for exploring thin-vein deposits using drilling instead of pitting. Background Technology

[0002] The Xiong'ershan mineral cluster in western Henan Province is formed by the collision of the North China and Yangtze tectonic plates during the Early-Middle Triassic, creating the Qinling orogenic belt. Intense crust-mantle interaction triggered large-scale regional metamorphism and magmatic activity, ultimately leading to widespread non-ferrous and precious metal mineralization. Similar deposits in this region are common throughout China, characterized by thin ore bodies, poor continuity, and significant variations in grade, making geological exploration and large-scale development challenging. Existing mines in this region, after years of mining, are now facing insufficient recoverable reserves, significantly impacting their production succession. Therefore, expanding recoverable reserves through exploration is a pressing issue that needs to be addressed by similar older mines in this region and across the country. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, this invention discloses a drilling-instead-of-pit exploration method for thin-vein deposits. Based on geological data accumulated during existing mine exploration and mining processes, and existing mine shaft space data, a full-data three-dimensional geological model and a tunnel space model are constructed using a computer. The computer analyzes the geological conditions of mineralization regularity based on the full-data three-dimensional geological model. Based on the full-data three-dimensional geological model and the tunnel space model, pit drilling is designed and carried out. Taking advantage of the shallow depth and low cost of pit drilling, the method reduces resource exploration costs while extending the mining life of old mines and increasing recoverable resource reserves.

[0004] To achieve the aforementioned objectives, this invention employs the following technical solution: a method for exploring thin-vein ore deposits using drilling instead of pit drilling. Based on geological data accumulated during existing mine exploration and mining processes, and existing mine shaft space data, a full-data three-dimensional geological model and a tunnel space model are constructed using a computer. The computer analyzes the geological conditions for mineralization based on the full-data three-dimensional geological model. Based on the full-data three-dimensional geological model and tunnel space model, for the inner part of the known ore body enclosed by the outermost tunnel envelope in the tunnel space model, the possible ore body locations are predicted based on the full-data three-dimensional geological model. With the goal of minimizing engineering work, in-pit drilling is conducted on the possible ore body locations within the tunnels to control and determine the ore body's scale, shape, thickness, and grade. Based on the tunnel space model, for the unexplored upper, lateral, and deep areas outside the known ore body enclosed by the outermost tunnel envelope in the tunnel space model, drilling is conducted within the outermost tunnel of the tunnel space model using a method involving drilling. Drilling is conducted in pits with a fixed grid density to extend geological exploration to the periphery of known ore bodies. Further explanation: Currently, drilling and pit exploration are still the most widely used direct exploration techniques in metal deposit exploration both domestically and internationally. Both can directly sample, verify, observe, and log the ore body, making them the most widely applied and irreplaceable methods in the ore exploration stage. Pit exploration, especially underground pit exploration, has disadvantages such as high cost, large workload, slow progress, and long construction period. In contrast, drilling has advantages such as flexible layout, low cost, and fast progress. Under the same conditions, it can deploy more work, improve project control, increase resource reliability, and provide a large amount of geological and geochemical logging information, facilitating the establishment of a full-data three-dimensional geological model. Therefore, increasing the proportion of drilling in all stages of mine exploration has significant advantages in accelerating exploration progress, shortening exploration time, and reducing exploration costs.

[0005] Furthermore, during drilling operations within the pit, altered mineralization samples were sent for basic analysis to determine the content of major ore-forming elements. Simultaneously, XRD phase analysis was performed using auxiliary samples, and the results were entered into a full-data three-dimensional geological model to form a full-data three-dimensional model for the extended geological exploration of the outer area. The full-data three-dimensional model for the extended geological exploration of the outer area was compared with the geological conditions of the ore-forming regularities derived by computer analysis based on the full-data three-dimensional geological model to preliminarily delineate the exploration area.

[0006] Furthermore, additional drilling operations are conducted in the delineated exploration area to carry out detailed exploration. Once the detailed exploration reaches the set control level, tunnel construction is carried out to the target ore block for verification. After verification, the mining area is delineated.

[0007] Furthermore, considering factors such as the average ore body thickness, size, and spatial distribution characteristics of different types of veins, the impact of in-pit drilling on the control density when the vein is basically controlled is analyzed. A systematic comparative analysis is conducted on the efficiency, cost, benefits, and exploration-to-production ratio of in-pit drilling. A comprehensive benefit analysis is performed on in-pit drilling for thin vein-type, lenticular, and nest-shaped small ore bodies. The optimal combination and ratio of in-pit drilling and exploration for different types of veins are summarized, and the engineering network density is determined. A corresponding combination model is established to establish a standard method for drilling instead of exploring in pits for thin vein-type deposits.

[0008] Due to the adoption of the above-described technical solution, the present invention has the following beneficial effects: The present invention discloses a drilling-instead-of-pit exploration method for thin-vein deposits. Based on geological data accumulated during existing mine exploration and mining processes, and existing mine shaft space data, a full-data three-dimensional geological model and a tunnel space model are constructed using a computer. The computer analyzes the geological conditions of mineralization regularity based on the full-data three-dimensional geological model. Based on the full-data three-dimensional geological model and the tunnel space model, for the known ore body inside the area controlled by the outermost tunnel envelope surface in the tunnel space model (the area already controlled by the tunnel space model), with the aim of finding "chicken coop ore," the possible ore body locations are predicted based on the full-data three-dimensional geological model. Pit drilling is then carried out within the tunnels to locate the possible ore body locations with minimal engineering work, controlling and determining the ore body's scale, shape, thickness, and grade. Based on the tunnel space model, for the known ore body outside the area controlled by the outermost tunnel envelope surface in the tunnel space model... In the unexplored areas above, laterally, and deep within the non-controlled area of ​​the tunnel space model, with the goal of finding new mineral resource reserves, in-tunnel drilling is conducted in the outermost tunnel of the tunnel space model to extend geological exploration to the periphery of known ore bodies. In-tunnel drilling, due to its shallow depth (compared to surface drilling), has lower exploration costs. This allows for the re-exploration of previously considered high-cost, uneconomical "chicken coop" mines within the existing tunnel control area. Simultaneously, leveraging the proximity of existing tunnels to these "chicken coop" mines and their low mining costs (tunneling costs were already shared in the early stages), these mines are exploited, thereby extending the lifespan of old mines. Furthermore, utilizing the low exploration cost of in-tunnel drilling within the tunnels, extended geological exploration is conducted outside the non-controlled area of ​​the tunnel space model, increasing recoverable resource reserves while reducing resource exploration costs. Detailed Implementation

[0009] The present invention will be explained in detail through the following embodiments. The purpose of disclosing the present invention is to protect all technical improvements within the scope of the present invention.

[0010] A drilling-instead-of-pit exploration method for thin-vein deposits is proposed. Based on geological data accumulated during existing mine exploration and mining, and existing mine shaft and tunnel space data, a full-data 3D geological model and tunnel space model are constructed using a computer. The computer analyzes the geological conditions for mineralization based on the full-data 3D geological model. Based on the full-data 3D geological model and tunnel space model, for the known ore body within the outermost tunnel envelope of the tunnel space model, the location of potential ore bodies is predicted according to the full-data 3D geological model. With the goal of minimizing engineering work, in-pit drilling is conducted within the tunnels to determine the ore body's size, shape, thickness, and grade. Based on the tunnel space model, for the unexplored upper, lateral, and deep areas outside the known ore body within the outermost tunnel envelope of the tunnel space model, in-pit drilling is conducted within the outermost tunnel of the tunnel space model with a set grid density, extending geological exploration to the periphery of the known ore body.

[0011] During drilling operations within the pit, altered mineralization samples were sent for basic analysis to determine the content of major ore-forming elements. Simultaneously, XRD phase analysis was performed using auxiliary samples, and the results were entered into a full-data three-dimensional geological model to form a full-data three-dimensional model for the extended geological exploration of the outer area. The full-data three-dimensional model of the extended geological exploration of the outer area was compared with the geological conditions of the ore-forming regularity derived by computer analysis based on the full-data three-dimensional geological model to preliminarily delineate the exploration area.

[0012] Supplementary drilling operations are carried out in the delineated exploration area, and detailed exploration is conducted in the delineated exploration area. After the detailed exploration reaches the set control level, tunnel construction is carried out to the target ore block for verification. After verification, the mining area is delineated.

[0013] This study considers factors such as the average ore body thickness, size, and spatial distribution characteristics of different types of veins to assess the impact of in-pit drilling on the control density of the vein when it achieves basic control. A systematic comparative analysis is conducted on the efficiency, cost, benefits, and exploration-to-production ratio of in-pit drilling. A comprehensive benefit analysis is performed on in-pit drilling for thin-vein, lenticular, and small-scale ore bodies. The study summarizes the optimal combination and ratio of in-pit drilling and exploration for different types of veins, as well as the optimal engineering network density. A corresponding combination model is established to develop a standard method for drilling instead of in-pit exploration in thin-vein deposits.

[0014] Taking the Yuelianggou lead-zinc-silver mine in the Xiong'ershan mining area of ​​western Henan as an example, the implementation method of this invention is specifically explained: After years of exploration and mining, the Yuelianggou lead-zinc-silver mine has accumulated a large amount of geological data and mining tunnel network. Based on the existing large amount of geological data, in conjunction with the Institute of Mineral Resources of the Chinese Academy of Geological Sciences, China University of Geosciences (Beijing), Central South University and other leading scientific research institutions, in-depth research was conducted on the topics of metallogenic geology, ore field structure, mineralogy, ore-forming material composition and metallogenic prediction in the mining area to explore the genesis of the deposit. Metallogenic model and prediction model were established by combining Micromine software. At the same time, tunnel space model was established by using the existing drilling engineering, shaft and tunnel engineering data implemented at various stages.

[0015] The Yuelianggou lead-zinc-silver mine is located in the Xiong'ershan mining area in western Henan Province. This mining area is formed by the collision of the North China and Yangtze plates during the Early-Middle Triassic, which created the Qinling orogenic belt. The intense crust-mantle interaction triggered large-scale regional metamorphism and magmatic activity, ultimately leading to widespread mineralization of non-ferrous and precious metals in the region. The Yuelianggou lead-zinc-silver mine is located in the eastern part of this orogenic belt. Since the mid-1980s, a series of large and medium-sized silver-lead-zinc (gold) deposits, such as Yuelianggou, Tieluping, Longmenmen, and Haopinggou, have been discovered in this area. These deposits are characterized by thin veins, numerous small ore bodies, and significant challenges in exploration and mining.

[0016] The Yuelianggou lead-zinc-silver mine is a typical example of this type of deposit in the region. The mining area features well-developed fault structures, occurring in clusters and belts, which can be broadly divided into three groups of faults, primarily trending NNE, followed by near-SN and near-EW. Production in this mining area is concentrated within the 260–800 meter elevation range, with most veins controlled within this section. However, with the mining focus shifting downwards year by year, recent years have seen increasing production costs, an imbalance in ore reserves across the three levels, and insufficient recoverable resource reserves. Furthermore, the exploration and mining operations have been hampered by long construction periods, high costs, large amounts of solid waste, and significant safety hazards, significantly impacting normal production succession. In addition, other deposits within the mining cluster are facing similar problems after years of mining.

[0017] Under this practical need, deepening the exploration of "chicken coop" deposits and conducting regional geological exploration to increase resource reserves has become an inevitable requirement for the future mineral resource exploration of the Yue Liang Gou lead-zinc-silver mine. Combining the full-data 3D geological model and tunnel space model constructed by computer at the Yue Liang Gou lead-zinc-silver mine, the method for deepening the exploration of "chicken coop" deposits in areas already controlled by the tunnel space model is as follows: Based on the full-data 3D geological model, the potential spatial location of ore bodies is predicted. Combined with the tunnel space model, the minimum engineering workload (shortest total drilling depth) is designed, and in-tunnel drilling is conducted at the potential ore body locations to preliminarily determine the ore body's scale, shape, thickness, and grade. In this embodiment, the reason for first using in-tunnel drilling for preliminary exploration of "chicken coop" deposits is that the existing tunnel network has effectively divided the underground space of the already mined area. The original small, scattered, and thin "chicken coop" deposits are already under the control of the existing tunnel network, and the cost of drilling exploration in these areas is relatively low compared to the original... The cost of exploration through surface drilling is significantly reduced, thus demonstrating economic benefits. The initial spacing of drilling operations within the tunnels is typically 100m along the strike of the ore body and 100m along the dip direction. In practice, the principle of gradual increase in density and depth is followed. Given the significant variations in ore body size, thickness, and grade at the Yue Liang Gou lead-zinc-silver mine, the minimum drilling density in the later stages is usually around 50m. During in-pit drilling, altered mineralization samples are sent for basic analysis to determine the content of major ore-forming elements, and XRD phase analysis is performed simultaneously using auxiliary samples. As the in-pit drilling progresses, various geological and geochemical data are collected and databases are established. Micromine software is used for mapping and analysis to determine whether the drilling operation has achieved the required control level of the "Jiwo" ore vein at a certain elevation. After the drilling operation achieves the required control level, the tunnel construction proceeds to the target ore block for verification. Once the control level is again achieved, the mining area is delineated, thereby extending the mining life of the old mine.

[0018] In terms of expanding geological exploration to the periphery of the known ore body, the Yuelianggou lead-zinc-silver mine utilizes a computer-generated full-data 3D geological model and tunnel space model. For the unexplored upper, lateral, and deep areas outside the known ore body enclosed by the outermost tunnel envelope in the tunnel space model, the first stage involves drilling within the outermost tunnel of the tunnel space model using a grid of 120*120m to expand geological exploration to the periphery of the known ore body. During the drilling operation... For drilling core sampling, half of the core is cleaved along its long axis to obtain a sample. The sampling length is generally around 0.50–1.00 m, with a maximum sampling length not exceeding 1.5 m. Sampling should be strictly performed according to different mineral types, ore varieties, structures, and pore sizes. Basic analytical elements include Ag, Pb, Zn, Au, and Cu. For veins with significant gold mineralization, As (As₂O₃) should be additionally analyzed. XRD phase analysis is performed using the auxiliary sample powder from the basic analysis, focusing on chromium mica, sericite, ferroalloy, and diatomite. The relationship between the changes in the content of alteration minerals such as calcite, quartz, chlorite, epidote, and potassium feldspar and mineralization was investigated. Geological data was collected and digitized, visualized, and statistically analyzed using Micromine software. Multiple independent data files in the geological database were linked by project number and imported into Micromine to form a relational database. The tunnel engineering and drilling trajectories were delineated, and a wireframe model of the ore body was constructed. The geological data from the outward exploration were analyzed using metallogenic models and prediction models. Reasonable extrapolation was performed based on existing mineral deposits to predict the metallogenic structures in non-control areas of the tunnel spatial model and to delineate preferred prospecting target areas. A second-stage detailed investigation was conducted on the delineated preferred prospecting target areas, studying previous production exploration, analyzing the roles and shortcomings of tunnel exploration, core drilling, and in-pit drilling in production, and classifying them in detail according to the specific characteristics of different veins in different mining areas. The required engineering density for the control target areas was initially determined. In this embodiment, the engineering grid size for the extended geological exploration was set at 60*60m.

[0019] In the current implementation of the drilling-instead-of-pit exploration method for thin-vein deposits at the Yuelianggou lead-zinc-silver mine, the engineering control density of drilling operations is not optimal for different types of veins. Therefore, in the specific implementation of the drilling-instead-of-pit exploration method for thin-vein deposits in different types of veins, it is necessary to consider factors such as the average ore body thickness, size, and spatial distribution characteristics of different types of veins, and to analyze the impact of the control density of the in-pit drilling project on the basic control of the ore vein. A systematic comparative analysis should be conducted on the efficiency, cost, benefits, and exploration-to-production ratio of the in-pit drilling project. A comprehensive benefit analysis of the in-pit drilling project for thin-vein, lenticular, and nest-shaped small ore bodies should be carried out. The optimal combination and ratio of in-pit drilling and pit exploration applicable to different types of veins should be summarized, and a corresponding combination model should be established to establish a standard drilling-instead-of-pit exploration method for thin-vein deposits.

[0020] The parts of this invention not described in detail are prior art.

Claims

1. A drilling-instead-of-pit exploration method for thin-vein type deposits, based on geological data accumulated during existing mine exploration and mining processes, and existing mine shaft and tunnel space data, constructs a full-data three-dimensional geological model and tunnel space model using a computer; the computer analyzes the full-data three-dimensional geological model to derive the geological conditions for mineralization; its characteristics are: Based on the full-data 3D geological model and tunnel space model, for the known ore body inside the outermost tunnel envelope surface of the tunnel space model, the possible ore body locations are predicted according to the full-data 3D geological model. With the goal of minimizing engineering work, in-pit drilling is carried out in the tunnel for the possible ore body locations to control and determine the ore body's scale, shape, thickness, and grade. Based on the tunnel space model, for the unexplored areas above, laterally, and deep outside the known ore body outside the outermost tunnel envelope surface of the tunnel space model, in-pit drilling is carried out in the outermost tunnel of the tunnel space model with a set grid, to conduct extended geological exploration to the periphery of the known ore body. Based on the average ore body thickness, size, and spatial distribution characteristics of different types of veins, this study systematically compares and analyzes the efficiency, cost, benefits, and exploration-to-production ratio of in-pit drilling when the in-pit drilling project has achieved basic control over the vein. A comprehensive benefit analysis of in-pit drilling is conducted for thin-vein, lenticular, and nest-shaped small ore bodies. The study summarizes the optimal combination and proportion of in-pit drilling and exploration for different types of veins, as well as the engineering network density, and establishes corresponding combination models to establish a standard method for drilling instead of in-pit exploration in thin-vein deposits.

2. The drilling-instead-of-pit exploration method for thin-vein type deposits according to claim 1, characterized in that: in During drilling operations in the pit, altered mineralized samples were sent for basic analysis to determine the content of major ore-forming elements. Simultaneously, XRD phase analysis was performed using auxiliary samples, and the results were entered into a full-data three-dimensional geological model to form a full-data three-dimensional model for the expansion of the outer area's geological exploration. The full-data three-dimensional model of the expansion of the outer area's geological exploration was compared with the geological conditions of the ore-forming regularities derived by computer analysis based on the full-data three-dimensional geological model to preliminarily delineate the exploration area.

3. The drilling-instead-of-pit exploration method for thin-vein type deposits according to claim 2, characterized in that: Further drilling operations were carried out in the delineated exploration area, and detailed exploration was conducted in the delineated exploration area. After the detailed exploration reached the set control level, the tunnel construction was carried out to the target ore block for verification. After verification, the mining area was delineated.