For underground mining here are some of the most common UG mining terms used by professionals in the field:
Adit
An adit is a horizontal or nearly horizontal entrance to an underground mine. It is a vital component of a mine’s infrastructure, providing access to the underground workings. Adits are typically driven into the side of a hill or mountain to reach valuable mineral deposits.
Explanation:
Adits are constructed to allow miners and equipment to enter the mine safely. They provide a more accessible and convenient means of accessing ore bodies compared to vertical shafts, especially in areas where the terrain permits such construction.
Adits are particularly advantageous in situations where the ore body is located at a relatively shallow depth beneath the surface. They can be driven directly into the side of a mountain or hill, minimizing the need for extensive vertical excavation.
Example Study:
In the historical Comstock Lode silver mines of Nevada, USA, adits were extensively used to access the rich silver veins. Miners would enter through the adit, and from there, they could explore various levels and chambers within the mine. These adits were often reinforced with timbering to provide structural support.
Additionally, the Sunshine Mine in Idaho, USA, employed a strategically positioned adit to gain access to deep-seated silver deposits. The adit facilitated the transportation of miners, equipment, and ore in and out of the mine, playing a pivotal role in the productivity of the operation.
Adits remain a crucial element in modern mining operations, providing an efficient and practical means of entry into underground workings.
Back
In the context of underground mining, the “back” refers to the roof or overhead surface of an excavation. It is the layer of rock or material that forms the upper boundary of the underground space. The stability and support of the back are of paramount importance to ensure the safety of miners and the integrity of the mine workings.
Explanation:
The back is subject to various types of stresses and pressures in an underground environment. These can include the natural weight of overlying rock, as well as dynamic forces from mining activities such as drilling, blasting, and the movement of equipment. Ensuring the stability of the back is a critical aspect of mine design and operation.
Support systems such as roof bolting, rock bolting, and other reinforcement techniques are often used to secure the back and prevent potential collapses or rockfalls. Additionally, ground control measures like shotcrete and meshing may be applied to provide further stability.
Example Study:
In the deep-level gold mines of South Africa’s Witwatersrand Basin, the stability of the back is a constant concern due to the extreme depths and pressures involved. Here, sophisticated ground control measures, including extensive bolting systems and the application of shotcrete, are employed to secure the backs of the excavations.
In the modern mining operations of the Sudbury Basin in Ontario, Canada, where nickel and copper are extracted, careful monitoring and reinforcement of the back are crucial. This includes the use of rock bolting and meshing to support the overhead rock strata in the complex network of tunnels and chambers.
The term “back” underscores the significance of ensuring a safe and stable overhead environment within underground mines, emphasizing the importance of proper ground control measures to protect the well-being of miners and maintain the integrity of the workings.
Chute
In underground mining, a chute is a specialized loading arrangement designed to facilitate the movement of materials, typically ore or waste rock, within the mine workings. It operates on the principle of gravity, allowing materials to flow from a higher to a lower elevation.
Explanation:
Chutes are crucial components in a mine’s material handling system. They are used to transport ore from various parts of the mine to a central collection point, such as an ore pass or a conveyor belt system. Chutes are designed to control the flow of material, ensuring a steady and controlled movement.
They come in various configurations depending on the specific needs of the mine. Some chutes may be inclined, allowing materials to slide down, while others may be vertical, aiding in the transfer of materials between different levels within the mine.
To prevent excessive wear and damage, chutes are often lined with abrasion-resistant materials. They may also incorporate baffles or other features to control the flow and reduce the impact of falling material.
Example Study:
In the Grasberg Mine in Papua, Indonesia, one of the world’s largest copper and gold mines, chutes play a critical role in transporting ore from the high-altitude mining areas to the processing plant located at a lower elevation. The chutes are strategically positioned to ensure a steady flow of ore down to the processing facilities.
Additionally, in the Sudbury Basin mines in Ontario, Canada, where nickel and copper are extracted, chutes are used extensively to transport ore from stopes and other mining areas to ore passes, which then facilitate the movement of material to the surface.
Chutes are integral to the efficient and safe movement of materials within underground mines. Their proper design and maintenance are crucial for optimizing the flow of ore and waste rock and ensuring the overall productivity of the mining operation.
Cone
In underground mining, a cone refers to a funnel-shaped excavation located at the top of an underground chamber or passageway. It serves to facilitate the controlled movement of materials, often ore or waste rock, from higher elevations to lower levels within the mine.
Explanation:
Cones are designed to direct the flow of materials, allowing them to smoothly transition from a wider opening at the top to a narrower point below. This shape harnesses the force of gravity to aid in the movement of materials, ensuring a controlled descent.
They are especially useful in scenarios where the terrain within the mine presents variations in elevation, requiring a controlled channel for material flow. By using a cone, the mine operators can efficiently direct materials to the desired destination, such as an ore pass or a loading point.
Example Study:
In the Kiruna Mine in Sweden, one of the world’s largest underground iron ore mines, cones are extensively used to guide the movement of broken ore from the production areas to the ore passes. These cones ensure a steady and controlled flow of ore down to the ore passes, which then facilitate the transportation of the material to the surface for processing.
Additionally, in the Kibali Gold Mine in the Democratic Republic of Congo, cones are employed in certain areas of the underground workings to direct the flow of ore towards the ore handling infrastructure, streamlining the movement of material for processing.
The utilization of cones in underground mining exemplifies the ingenuity in design to optimize material flow and transportation within the mine, ultimately contributing to the efficiency and productivity of the operation.
Crosscut
In underground mining, a crosscut is a horizontal or nearly horizontal underground opening driven to intersect or reach an ore body. This critical excavation allows miners to access and extract valuable minerals from within the rock formation.
Explanation:
Crosscuts are essential components of the mine layout and provide vital access points to the ore bodies. They are typically driven perpendicular or at an angle to the strike (main direction) of the mineral deposit. By intersecting the ore body, miners can effectively extract the valuable material.
Crosscuts serve various purposes, including providing access for miners and equipment, creating ventilation pathways, and establishing routes for the transportation of ore and waste rock.
Example Study:
In the Red Lake Gold Mine located in Ontario, Canada, crosscuts played a pivotal role in accessing the gold-bearing quartz veins. These crosscuts were driven from the main shaft towards the identified ore bodies. Once intersected, additional drifts and raises were established for extraction, illustrating the critical role of crosscuts in the mining process.
Similarly, at the Olympic Dam mine in South Australia, where copper, uranium, and other minerals are extracted, crosscuts are driven to reach the various mineralized zones within the complex ore body. These crosscuts are carefully planned to maximize the efficiency of ore extraction.
Crosscuts exemplify the strategic planning and execution required in underground mining operations. They provide the necessary access points to reach valuable mineral deposits efficiently and form a fundamental part of the mine’s infrastructure.
Dip
In mining, “dip” refers to the angle at which an ore deposit or geological stratum inclines from the horizontal plane. It provides critical information about the orientation of the deposit, which is vital for planning and executing mining operations.
Explanation:
Understanding the dip of an ore deposit is crucial for miners and geologists. It determines how the deposit is oriented within the earth’s crust, influencing the design of mine layouts, the direction of drilling and blasting, and the most efficient methods for extracting the valuable minerals.
The dip angle is measured in degrees and is determined by the angle formed between a horizontal plane and the geological stratum or ore body. A dip angle of 0 degrees would indicate a horizontal deposit, while an angle greater than 0 degrees indicates an inclined or dipping deposit.
Example Study:
In the copper mines of Chuquicamata in Chile, the ore body exhibits a significant dip angle. This geological characteristic influences the mining methods employed. The mine utilizes open-pit mining techniques that follow the dip of the deposit, allowing for efficient extraction of the copper ore.
Similarly, in the Zinkgruvan mine in Sweden, which produces zinc, lead, and silver, the ore body has a distinct dip angle. Miners employ specialized drilling and blasting techniques to extract the ore efficiently while considering the angle of the dip.
The knowledge of the dip of an ore deposit is fundamental in determining how it is approached and extracted. It guides the planning and execution of mining activities, ultimately influencing the efficiency and safety of underground operations.
Draw Point
A draw point in underground mining is a location beneath the stoping area where gravity is used to facilitate the transfer of ore to a loading point. It plays a pivotal role in the process of ore removal within the mine.
Explanation:
Draw points are strategically positioned beneath active stoping areas where ore is being extracted. After blasting and fragmentation, the ore naturally flows or is assisted by gravity to these points. From there, it can be easily collected and transported to the surface or to other parts of the mine for further processing.
The design and placement of draw points are critical for optimizing the flow of ore within the mine. They are typically located in positions that allow for efficient collection without impeding the mining process. The size and configuration of draw points may vary based on the specific needs of the mine and the characteristics of the ore deposit.
Example Study:
In the Stillwater Mine in Montana, USA, draw points are strategically positioned beneath the ore bodies rich in platinum and palladium. After blasting, the fragmented ore flows through chutes to the draw points. It is then loaded onto haulage equipment for transportation to the surface.
Similarly, in the Grasberg Mine in Indonesia, draw points are utilized to collect copper and gold ore from the high-altitude mining areas. Once the ore reaches the draw points, it is directed into chutes or onto conveyors for further processing.
Draw points are crucial components of the ore removal process in underground mining operations. Their strategic placement and efficient design contribute significantly to the overall productivity and profitability of the mine.
Drift
In underground mining, a drift is a horizontal or nearly horizontal underground opening that provides access to various parts of the mine. Drifts serve as essential passageways for miners, equipment, and materials within the mine workings.
Explanation:
Drifts are primary access routes within a mine, allowing personnel and equipment to move horizontally through the underground workings. They are typically excavated perpendicular to the strike (main direction) of the deposit or at a slight incline. Drifts may be used for various purposes, including transportation, ventilation, and as pathways to reach specific ore bodies.
Drifts are an integral part of the mine layout and are strategically planned to optimize the movement of personnel and materials while ensuring safety and efficiency.
Example Study:
In the Carlin Trend gold mines in Nevada, USA, extensive drift networks are excavated to provide access to the numerous ore bodies scattered throughout the deposit. These drifts connect various parts of the mine, allowing miners and equipment to efficiently reach the working faces.
Additionally, in the Sudbury Basin mines in Ontario, Canada, where nickel and copper are extracted, drifts are driven to provide access to the ore bodies. Ventilation systems are often integrated within the drifts to ensure adequate airflow throughout the mine.
Drifts represent the lifeline of underground mining operations, providing crucial access to the valuable ore bodies. They are meticulously planned and executed to optimize the movement of personnel and materials, ultimately contributing to the efficiency and productivity of the mining operation.
Finger Raise
A finger raise, also known as a multiple or branched raise, is a system of several raises that converge or branch together to a common delivery point within an underground mine. This configuration is used to efficiently transfer ore or other materials from lower to higher levels or vice versa.
Explanation:
A finger-raise system is designed to streamline the movement of materials within a mine. It involves the excavation of multiple vertical or inclined openings (raises) that converge at a central point. These raises act as conduits for the material to flow between different levels of the mine.
The term “finger” is used to describe how the raises branch out, resembling the shape of fingers on a hand. This design allows for the simultaneous transfer of materials from multiple locations to a single collection point, increasing operational efficiency.
Example Study:
In the Broken Hill Mines in New South Wales, Australia, finger raises were used extensively for the efficient movement of lead and zinc ore to the surface for processing. The ore bodies in this region were often found at varying depths and orientations, making the finger-raise system an ideal solution for material transfer.
Similarly, in the El Teniente Mine in Chile, one of the world’s largest underground copper mines, a network of finger raises is employed to transport ore from different levels to a central loading area. This system helps to optimize the flow of ore within the complex underground workings.
Finger raises exemplify the innovative design and engineering solutions employed in underground mining operations. By efficiently channelling the flow of materials, they contribute to the overall productivity and profitability of the mine.
Footwall
The footwall is a fundamental term in geology and mining, referring to the lower boundary or surface of an ore deposit or geological stratum. It is the rock or material that lies beneath the ore body and provides a critical reference point for mining operations.
Explanation:
In an inclined or vertical ore deposit, the footwall is the lowermost layer or boundary that supports the weight of the overlying rock and the ore body itself. Understanding the characteristics of the footwall is crucial for miners and geologists as it impacts the stability of the excavation and influences mining methods and equipment selection.
Analyzing the composition, structure, and stability of the footwall is essential for ensuring the safety of miners and the integrity of the mine workings. It also provides valuable information about the geological context of the ore body.
Example Study:
In the Sudbury Basin mines in Ontario, Canada, where nickel and copper are extracted from massive sulphide deposits, the footwall is composed of various rock types, including gabbro and other igneous formations. The properties of the footwall are carefully assessed to determine the most suitable mining methods and ground support systems.
Similarly, in the Carlin Trend gold mines of Nevada, USA, where sedimentary rock formations host gold deposits, understanding the characteristics of the footwall is crucial for designing effective ground control measures and ensuring the stability of the underground excavations.
The footwall provides essential geological and structural information that guides mining operations. It serves as a critical reference point for miners and geologists, influencing decisions related to mine design, ground support, and safety protocols.