Mining Knowledge Q&A

Author: Chief Editor: Xu Zhongyi et al
Publisher:
Publish Date: 1997-01-01
Features:
Content Summary This book comprehensively and systematically introduces mining-related knowledge from six aspects: mining fundamentals, mine geology, blasting and drilling, open-pit mining, underground mining, special mining, and mine technical economy and management, in the form of questions and answers. During the writing process, the authors extensively solicited opinions and suggestions from experts, scholars, and many field workers. The content is presented from simple to complex, with easy-to-understand language and as detailed and practical as possible. It is suitable for reference use by field workers, students, mine leaders, grassroots cadres, and individuals interested in mining knowledge.
Excerpt:
What is a mineral? A mineral is an inorganic substance with the same chemical composition and physical properties, formed under natural conditions in the natural world. The main elements constituting various minerals are oxygen, silicon, aluminum, iron, calcium, potassium, magnesium, etc. The Earth's crust is composed of rocks, rocks are composed of minerals, and minerals are composed of one or more chemical elements.
What is an ore? Various minerals in the Earth's crust that can be extracted using modern technologies such as mining, washing, and smelting to meet the needs of various sectors of the national economy and national defense construction are called ores. Ores from which metals are extracted are called metal ores, such as iron ore and copper ore; ores from which non-metallic elements, minerals, or those that can be directly utilized are called non-metallic ores, such as phosphorus, asbestos, mica, and limestone. Ores are divided into high-grade ores and low-grade ores based on their grade; they are classified as simple ores or composite ores based on the number of usable components they contain.
What is gangue? What is country rock? What is waste rock? The part of an ore that has no value or cannot be utilized is called gangue. For example, tungsten ore often forms in quartz veins, and such quartz veins are called gangue. The rocks surrounding a ore body are called country rock. The country rock above the ore body is called the upper plate or cover rock; the country rock below the ore body is called the lower plate or underfoot rock. Rocks embedded within the ore body are called interlayers. The country rock and interlayers are collectively referred to as waste rock. The concept of waste rock is relative; any rocks extracted during mining without industrial value are called waste rock.
What is the structure of rocks? The structure of rocks refers to the macroscopic state formed by the dynamic geological processes during and after the formation of rocks. It mainly includes bedding, schistosity, and joints. Bedding is the change in the composition of rocks in the vertical direction. Schistosity is the ability of rocks to split into thin sheets along parallel planes. When drilling in rocks with well-developed bedding, the drilling direction should be as perpendicular as possible to the bedding planes to prevent drill bits from getting stuck and reduce blasting efficiency. Generally, well-developed bedding is beneficial for blasting, but if it is too pronounced, it may hinder blasting effectiveness and even prevent the formation of properly shaped blast holes.
What are rocks? How are rocks classified? Rocks are near-homogeneous mineral bodies composed of one or more minerals. Examples include basalt, granite, and limestone. Rocks are divided into two major categories: (1) primary rocks; (2) loose overburden. Primary rocks are further classified into three types: (1) igneous rocks; (2) sedimentary rocks; (3) metamorphic rocks. Igneous rocks are formed when molten magma rises from the Earth's interior and intrudes into cracks in the crust, then cools and solidifies. Sedimentary rocks are formed by the deposition of fine mineral particles and organic matter in water accumulation areas. Metamorphic rocks are formed when ancient igneous rocks or sedimentary rocks undergo changes due to high temperatures, pressures, and chemical effects. Loose overburden, also known as colluvial deposits, is formed by the fragmentation of primary rocks due to the actions of surface water, wind, and temperature changes. The thickness of the overburden significantly influences the selection of mining methods, especially the development approach.
What is a mineral deposit? What is an industrial mineral deposit? A mineral deposit is a natural aggregation of ores formed under certain geological conditions. A mineral deposit that can be mined and utilized under current economic and technological conditions is called an industrial mineral deposit; otherwise, it is called a non-industrial mineral deposit.