Mine geological work is an indispensable basic technical work in mining. It refers to the geological work directly for production in the production area or mining area of ​​the deposit in the mining process, according to the needs of the mine work. The geological work of the mine geological work Based on the project of mine mining activities, it is the technical basis and basis for mining production and management activities. The mining activities must be moved with the advancement of mining operations. There is no fixed working space and place, and the working environment conditions are greatly affected by engineering geology and hydrogeological conditions. Therefore, in order to ensure the smooth progress of mining activities, it is necessary to understand the impact of mine geological structure, hydrogeology and rock properties on mine safety.

1. Deposits, ore bodies and surrounding rocks

(I) Deposits The useful minerals or components enriched inside or on the surface of the earth's crust, which meet the requirements of industrial utilization in terms of quality and quantity, and which can be exploited under the existing technical economic conditions are called deposits. The space of the deposit includes the ore body and surrounding rock.

(II) Ore body The basic unit that constitutes the bed body is the ore-bearing part that meets the industrial requirements and is also the direct object of mining. The ore body has a certain size, shape and appearance. A deposit can consist of one or more ore bodies.

(3) Ore refers to a mineral aggregate containing useful minerals or components and forming an ore body. The ore usually consists of two parts: ore minerals and gangue minerals. It refers to a mineral ore ores can be useful Tigong element itself may be directly or minerals, such as copper ores, asbestos and other minerals. A gangue mineral is one that is of no use in the ore, such as quartz in copper ore. The grade of ore refers to the content, composition or mineral content (expressed in mass percentage, g/t, g/m ³ , g/t) contained in the unit ore.

(4) Surrounding rock Refers to rocks that have no economic value around the ore body. The boundaries between the ore body and the surrounding rock are clear, and there is no obvious limit to the gradual change. Generally, in the deposit, the part that can reach the lowest industrial average grade is regarded as the ore body, and the part that can not be reached is used as the surrounding rock. With the improvement of process technology, the minimum industrial grade can be reduced, so that the scope of the ore body can be enlarged.

2. Mineralization and genetic classification of deposits

Mineralization is the separation of the useful components (elements or compounds) in the earth's crust and the rest of the components, and the geological action of the deposits in the local concentration. This process of local enrichment is extremely complex and the mineralization is diverse. From the perspective of metallogenic geological processes and sources of ore-forming materials, mineralization can be divided into three categories:

(1) Internal mineralization The mineralization is caused by internal dynamic geological processes and is directly or indirectly related to magmatic activity. The deposit formed by the internal ore-forming action at high temperatures is called an endogenetic deposit. Endogenous deposits are mainly formed by local enrichment of ore-forming materials during magmatic activity.

(II) External ore-forming action This mineralization occurs on the surface of the earth and is caused by external dynamic geological processes. The deposit formed by the external ore-forming action at the surface temperature is called the exogenous deposit. The ore-forming materials of exogenous deposits are mainly derived from surface rocks or primary deposits, which are formed by local enrichment during weathering, handling and sedimentation.

(III) Metamorphism and mineralization Metamorphism and mineralization occur in the interior of the earth's crust, and most of them are caused by regional metamorphism in the internal dynamic geological action. The metamorphic ore deposits cause the endogenous and exogenous deposits to be deep in the earth's surface, subject to new physicochemical conditions such as temperature, pressure, gas and hydrothermal fluids, which cause changes in their composition and structure to form new deposits called metamorphic deposits.

Third, the shape and occurrence of the deposit

The shape and occurrence of the ore body are determined by various factors, the most important of which is the cause of the deposit, followed by the structural conditions and the nature of the surrounding rock.

   (1) The shape of the ore body

1. According to the inclination angle of the ore body, the ore body classification is shown in Table 1.

    (2) The occurrence of the ore body

The occurrence of the ore body includes the following aspects.

1. The ore-forming elements of the ore body are mainly used to determine the spatial position of the platy ore body. The method of representation is the same as that of the general rock formation, that is, it is expressed by the trend, inclination, inclination, and inclination. However, for columnar ore bodies, lenticular ore bodies, etc., their lodging angle and inclination angle are also measured.

2. Relationship between ore body and surrounding rock Refers to which kind of rock is produced by the ore body; the ore body is produced parallel to the bedding or lamella of the surrounding rock, or is intercepted by them.

3. The spatial positional relationship between the ore body and the intrusive rock mass refers to whether the ore body is produced in the interior of the rock mass, or in the contact zone between the surrounding rock and the invading rock, or in a distance from the contact with a certain distance. In the rock.

4. Ore body burial refers to the spatial position of the ore body is the blind ore body exposed on the surface or hidden in the ground, and the burial depth of the ore body.

5. Arrangement direction of ore body refers to a series of arrangement directions and laws with genetic connection.

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