1. PRINCIPLES OF OPEN DEVELOPMENT OF DEPOSITS OF MINERAL RESOURCES .. 4

1.1 Types of developed fields and deposits. 4

1.2. Types of open pit mining. 7

1.3 Types and sizes of quarry fields. nine

1.4 Open pit mining periods. 12

1.5 The concept of the mode and stages of mining. fourteen

2. THEORY OF OPENING WORKING HORIZONS.. 18

2.1. The procedure for the formation of cargo flows. eighteen

2.2. Prerequisites for the formation of cargo flows. 20

2.3. Initial stages of mining development. 22

2.4. Revealing mine workings. 23

2.5. Ways of opening the working horizons of a quarry. 25

2.6. The routes of opening workings. 27

2.7. Forms of routes of capital workings. 29

2.8. Schemes and systems of revealing routes. 31

2.9. Schemes for the development of quarry railway tracks. 33

2.10. Quarry road schemes and their main parameters 35

2.11. Sliding and semi-stationary ramps.. 37

2.12. Trenching for road and conveyor transport 40

2.13. Conducting trenches. 41

2.14. Volumes of capital trenches and half-tranches (according to prof. E.F. Sheshko) 46

2.15. Cutting trenches and pits.. 51

3. SYSTEMS FOR THE DEVELOPMENT OF MINERAL DEPOSITS 54

3.1. Classification of open pit mining systems. 54

3.2. Classifications of mining systems according to the direction of movement and the method of stripping operations. 59

3.3. Dividing a quarry field into excavation layers. 60

3.4. Height and stability of ledges. 62

3.5. Structures and stability of quarry walls. 66

3.6. Choice of development system. 68

3.7. Basic principles and patterns of formation of the working area of ​​a quarry. 68

3.6. Longitudinal and transverse development systems. 75

3.7. Fan and ring mining systems. 76

4. SYSTEMS FOR THE DEVELOPMENT OF HORIZONTAL AND SLOW FIELDS. TECHNOLOGICAL SCHEMES. 79

4.1 Opening of working horizons in continuous mining systems 79

4.2. Opening methods. 84

4.3. Conditions for the use of deep development systems. 86

4.4. Options for the development of mining operations. 89

4.5. Designs and parameters of berms. 92

5. OPENING OF WORKING HORIZONS IN DEEP DEVELOPMENT SYSTEMS.. 93

5.1. Opening by external capital trenches. 93

5.2. Simple, dead-end and loop tracks.. 96

5.3. Spiral tracks.. 102

5.4. Characteristics of schemes and systems of revealing traces. 106

6. MINING AND GEOMETRIC ANALYSIS OF CARRIER FIELDS.. 110

6.1. Mining and geometric analysis of quarry fields with horizontal and flat deposits. 112

6.2 Mining and geometric analysis of quarry fields for steeply dipping and inclined deposits with difficult occurrence conditions according to the method of A.I. Arsentiev * 114

6.3 Converting graphs of mining and geometric analysis into a calendar graph. 117

6.4. Building a rational calendar schedule mining 122

6.5. Determining the area of ​​possible regulation of the mountain regime schedule 125

6.5. Technological methods of regulating the mode of mining operations 129

6.6. Determination of a rational direction for the development of mining operations in a quarry in the development of homogeneous deposits according to the method of A.I. Arsentiev 138

7. THEORY OF INTEGRATED MECHANIZATION OF OPEN MINING 142

7.1. General information. 142

7.2. Principles integrated mechanization. 143

7.3. Technological classification equipment complexes. 145

7.4. Structural classification of mechanization links. 151

7.5. Fundamentals of assembly of mining and transport equipment 154

8. TECHNOLOGICAL COMPLEXES FOR EXTRACTION OF BUILDING ROCKS.. 156

8.1. Technological complexes for the extraction and processing of sand and gravel rocks. 156

8.2. Technological complexes for the production of crushed stone. 160

8.3. Technological complexes for the extraction of natural stone. 165

LITERATURE.. 167

1. PRINCIPLES OF OPEN MINING OF MINERAL DEPOSITS

Types of developed fields and deposits

The objects of open mining are mineral deposits. On the basis of industry, open mining of coal and ore deposits, deposits of building rocks, cement raw materials, mining and chemical raw materials, etc.

Developed mineral deposits occur in very diverse natural conditions.

The types of deposits differ primarily in their characteristic geometric features.

1. Mineral deposits in form can be: isometric - developed more or less equally in all directions (massive deposits, stocks, nests, etc., Fig. 1.1, in, a);

plate-like - elongated mainly in two directions with a relatively small thickness (layers and reservoir-like deposits, Fig. 1.1, a, b, d, f);

tubular and columnar - elongated mainly in one direction;

intermediate and transitional between the indicated forms (lenses, veins, saddle-shaped deposits, folds, bends, tectonically disturbed formations) (Fig. 1.1, a, f).

The shape of deposits predetermines the shape of quarry fields.

2. Relief of the deposit surface it can be flat (Fig. 1.1, a), in the form of a slope of a hill (Fig. 1.1, b), in the form of a hill (see Fig. 1.1, c), hilly (Fig. 1.1, G) and finally, the deposit may be under water. The order of development and possible means of mechanization depend on the surface topography.

3. Depending on the position relative to the dominant surface level and depth deposits are distinguished:

surface type - directly exposed to the surface or located under deposits of small thickness (up to 20-30 m, Fig. 1.1, a)

deep type - located significantly below the dominant surface level, the thickness of the barren rocks can be from 40 to 250 m (Fig. 1.1, e, e) such deposits may be developed open or underground way, which is economically justified;

high-altitude type - located above the dominant level of the surface (Fig. 1.1, b, c) deposits can be objects of open or underground mining; high-altitude-depth type - partially located above and below the dominant surface (Fig. 1.1, g).

The occurrence may or may not be consistent with the surface topography; the deposit can occupy all or part of the hill (mountain slope). The size of the quarry in depth and in plan, as well as the technical means used, especially transport, depend on the position of the deposit relative to the earth's surface.

4. According to the angle of incidence deposits are distinguished:

gently sloping, characterized by a slightly inclined (up to 8-10°) and undulating occurrence of the main part of the deposit (see Fig. 1.1, a, G); their special case is horizontal deposits;

inclined - with angles of incidence from 8-10 to 25-30 ° (see Fig. 1.1.6);

steeply inclined - with angles of incidence of more than 25-30 ° (see Fig. 1.1, g)

steep - with angles of incidence of 56-90 ° (see Fig. 1.1.5);

complex occurrence, characteristic of anticlinal and synclinal folds (see Fig. 1.1, e) and sharp geological disturbances; it is distinguished by the variable direction of the fall of the deposit.

Such a division of deposits is adopted on the basis of open-pit mining technology. Thus, the placement of dumps in the worked-out space of a quarry is possible when developing horizontal and gently sloping deposits (Fig. 1.2, a) and in special cases - when developing elongated sloping and steeply sloping deposits. When developing inclined deposits, according to the conditions of stability of the end walls of the quarry and the placement of opening workings, it is usually not necessary to excavate the overburden of the lying side of the deposit (Fig. 1.2, b). With a steep drop, it is necessary to develop the host rocks, both hanging and recumbent sides of the deposit (Fig. 1.2, in).

By power deposits are divided into:

very low power, low power, medium power; powerful; very powerful.

Such a division is associated with the dependence of the number of simultaneously mined mining ledges on the thickness of the deposit. The conditions and procedure for the development of horizontal and inclined (steep) deposits are not the same, therefore, for these deposits, the indicators of the same thickness classes and the indicators of the same thickness classes are numerically different.

simple deposits (see Fig. 1.1, b, g) with a homogeneous structure, without significant layers and inclusions; in this case, all mineral deposits are taken out together (gross mining method);

complex deposits (see Fig. 1.1, a, d), containing, along with conditioned minerals, substandard varieties of it, as well as interlayers or inclusions of waste rocks with clearly defined contacts; in this case, separate (selective) development of conditioned and substandard minerals and waste rocks is necessary;

Dispersed deposits (Fig. 1.1, h), having a complex structure, in which conditioned and substandard minerals and waste rocks are distributed in the thickness of the earth's crust without a clear pattern and pronounced contacts; the choice of a separate or gross method of extracting a mineral is made after a detailed operational exploration.

5.Mineral quality in the deposit can be distributed:

Evenly, when the quality of the mineral that meets the requirements of the consumer is approximately the same within the deposit; in this case, the extraction (gross or separate) in different parts of the deposit can be carried out independently, without averaging;

uneven, when the distribution of quality is not the same in depth or in terms of the deposit; in this case, it is necessary to plan simultaneous extraction in different parts of the deposit, to have several working extraction sections and to average the quality.

6. By predominant breed types deposits can be represented:

Rocky overburden and minerals;

Heterogeneous overburden and rocky (semi-rocky) minerals and host rocks; in this case, the thick layer covering the deposits is represented by alternating soft, dense, semi-rocky and hard rocks;

Soft and dense overburden and rocky or semi-rocky minerals and wall rocks;

Semi-rocky overburden and semi-rocky or very dense minerals;

Soft overburden and heterogeneous minerals;

Soft overburden and soft or hard minerals.

These factors have a decisive influence on the choice technical means, order of conduct and the possibility of open-cast mining.

Deposits mean accumulations of useful substances in various layers of the earth's crust, suitable for development and further use in industry. The main criteria for determining the economic significance of a deposit are the quantity, quality and conditions of occurrence of its main component. website

There are many systems for classifying deposits according to various criteria, depending on the purpose of separation. Let's consider the main ones from the point of view of industrial and economic feasibility of development and value for the national economy. offbank.ru

By use

According to the type of the main elements of the deposit, it is customary to divide it into:

• Ore (metal). These are mineral deposits from which it is technologically possible and economically advantageous to extract valuable metals or their compounds (ferrous, non-ferrous, noble and radioactive metals). Most widely distributed in the earth's crust iron ores and bauxite (the main raw material for aluminum production).
• Non-metallic (non-metallic). Stocks of substances that can be used in pure or processed form for various industries economy (clay, gravel, sand, mineral fertilizers, salts).
• combustible. Substances used for the production of fuel and as raw materials for the chemical and metallurgical industries (oil, coal, gas, oil shale). The most common type of fuel resource is coal. Its share among all reserves of combustible minerals is about 75%. The remaining 25% is approximately equally divided between oil and combustible gas.
• Gemstones. They include stocks of precious, semi-precious and ornamental stones (diamonds, emeralds, sapphires, opal, jasper and many others).
• Hydromineral. Surface and ground water for domestic and technical use. This type of deposits differs from all previous ones in terms of renewability. https://www.site/

Although the end of the oil era and limited supplies are regularly reported, this type of fossil fuel remains the most sought after. Almost every oil deposit also contains an accompanying substance - combustible gas, therefore, in fact, they are oil and gas. There are deposits of pure gas. The most significant oil reserves are located in the territories of the Persian Gulf countries, Russia and the United States. www.site

For nuclear energy uranium is the main raw material. 45% of all explored and economically viable deposits are located in Australia, Kazakhstan and Canada.

Deposits of metal ores, including precious metals, are very significant for humanity. Geographically, they are not associated with sedimentary deposits, unlike oil deposits. Most of these deposits were formed as a result of movements of tectonic plates, forming basins of considerable length, and their presumed location is quite predictable. https://www.site/

Gold occurs in nature in small quantities in the form of placers or nuggets, the exploration and development of its reserves is associated with high costs, and the demand for this metal is quite large.

Useless types of minerals do not exist. All of them, to a greater or lesser extent, find application and make life easier for a person. offbank.ru

By location

The depth of occurrence of minerals is the main factor that determines the way the field is developed. On this basis, stocks are divided into:

• Open - go to the surface of the Earth or are in the uppermost layers. They are mined in a quarry way - such deposits are the simplest and most cost-effective to develop, but the most destructive to landscapes. Quarries, unlike mines, are characterized by lower energy costs, high productivity and a degree of mechanization. As a result, the cost end products, extracted from open deposits, is much lower. Coal, ore, non-metallic minerals are mined in a career way.
• Closed - are in deep bowels. For their extraction, more technological methods are used - mine for solid minerals, pumping or gushing method for pumping oil. These methods are more expensive and also the most dangerous for the health and life of workers. website

According to the degree of reliability

This is one of the most important criteria business case development. In the CIS countries, they adhere to a system that includes 4 groups:

1. Category A. Precisely and in detail explored reserves, about which all the main characteristics are known: the shape and size of deposits, grade and type of raw materials, production conditions.
2. Category B. Conditionally explored deposits without accurate data on size and spatial location.
3. Category C1. Poorly explored areas or reserves of complex geological structure.
4. Category C2. Promising deposits identified by the geological structure of the site. offbank.ru

Comparing these and many other factors, deposits are classified as:

• balance sheet, which makes sense to develop with modern level development of engineering and technology;
• or off-balance - they can be used in the future, but are not yet of value due to small volumes, poor quality of raw materials or geological features that make extraction difficult.

The variety of conditions under which they formed different types natural resources, explain the uneven distribution of them, although there is a certain pattern. Thus, sedimentary rocks accumulated on the flat areas of tectonic plates, and now deposits of combustible substances are more likely to be found there. In the folded formations of the earth's crust, minerals of igneous origin are most often formed. However, this distribution has many exceptions - often ore deposits are located on the plains, and oil is found in the mountains. https://www.site/

The export of natural resources is the backbone of Russia's long-suffering economy. Most of them are exported. The highest concentration and diversity of species is concentrated in Western Siberia, the most severe area in terms of natural conditions and remote from the main transport routes.

Mineral deposits are formed in the process of differentiation during the circulation of mineral masses in evolutionary development Earth. In accordance with this, all mineral deposits are divided into three series: magmatogenic, exogenous and metamorphogenic. Each series is in turn subdivided into groups, and the latter into classes.

Magmatogenic

(deep, hypogene, endogenous) mineral deposits are associated with the internal energy of the earth. The place of their localization is the deep geological structures that determine the conditions for the accumulation of mineral substances, the morphology, composition and structure of the bodies of minerals.

Magmatic the group includes deposits formed during the solidification of fractions of magmatic melts, in which valuable mineral compounds are concentrated.

Carbonatite the group was formed from melts associated with ultramafic alkaline intrusions of the central type .

Pegmatite the group includes deposits representing portions of solidified melts of acidic and alkaline magmas subjected to metasomatic action of hot mineralized gas-water solutions.

Albitite-greisen the group was created by postmagmatic alkaline solutions in the apical parts of acid and alkaline rock masses.

Skarn or contact-metasomatic the group covers deposits that arose as a result of metasomatism in the area of ​​heated contacts of cooling massifs of igneous rocks and adjacent carbonate-bearing sedimentary and effusive-sedimentary strata.

hydrothermal the group is formed in the depths of the earth's crust due to the deposition of mineral substances from hot mineralized gas-water solutions.

Pyrite the group includes deposits that have arisen in connection with the post-volcanic gas-hydrothermal activity of basaltic magma.

exogenous

(surface, supergene, sedimentogenic) deposits are associated with geochemical processes that took place in the past and are currently developing on the surface and in the near-surface layer of the Earth. The place of accumulation of minerals are:

1) the surface of the planet;

2) near-surface zone up to the groundwater level;

3) the bottom of swamps, rivers, lakes, seas and oceans.

The formation of exogenous deposits is associated with the mechanical, chemical and biochemical differentiation of the earth's crust under the influence of solar energy. Three groups of deposits are distinguished in this series: the weathering group, alluvial and sedimentary.

weathering deposits associated with the weathering crust, in which minerals accumulate due to the removal of useless compounds by surface waters and as a result of the redeposition of some valuable substances in the lower zone of the weathering crust and below it.

placer the group is formed during physical weathering and the associated mechanical destruction of mineral bodies, which include mechanically strong and chemically stable minerals that create placers.

sedimentary the group includes deposits that arise during the mechanical, chemical, biochemical and volcanic differentiation of mineral substances in the process of accumulation of sedimentary rock strata.

Metamorphogenic

deposits were formed during the intensive transformation of rocks at a considerable depth from the earth's surface in an environment of high temperatures and pressures. This series combines two groups of deposits. Metamorphosed deposits include previously formed deposits of any genesis transformed in a new thermodynamic setting. Metamorphic formed for the first time as a result of the metamorphic transformation of mineral matter.

Groups, classes and subclasses of the genetic grouping are subdivided into mineral formations as necessary. ore formation are called deposits of the same mineral composition, formed in similar physico-chemical and geological conditions. metallogenic formation called a complex of paragenetically related rocks of igneous, sedimentary or metamorphic origin and associated mineral deposits, due to the unity of origin in certain structural and formational conditions.

Geological conditions for the formation of deposits from the standpoint of the geosynclinal concept

The metallogeny of geosynclines has been studied to the fullest extent by Yu. Bilibin; it has been vividly embodied in the works of V. Smirnov. The main factors development of the earth's crust are geosynclinal systems - generators of the overwhelming mass of endogenous deposits. According to these studies, three main stages are distinguished in the history of the development of geosynclines: early, middle and late.

I. Early stage
(pre-orogenic, riftogenic)

covers the time interval from the inception of the geosyncline to the main phases of folding. At this time, deep splits appear, through which basaltic magma flows. Thick strata of volcanic-sedimentary rocks, penetrated by intrusions of ultrabasic and basic compositions, accumulate along the splits in the sagging bottom of geosynclines.

Four igneous formations form in the early stage:

1) basalt-liparitic submarine, pyrite copper-zinc-lead and oxide ferromanganese deposits are associated with it;

2) peridotite with magmatic deposits of chromites and platinoids;

3) gabbro with magmatic deposits of titanomagnetites and platinoids (platinum and palladium);

4) plagiogranite-syenite with skarn deposits of iron and copper.

In addition to igneous, five sedimentary formations are distinguished:

1) clastic(conglomerates, siltstones, clays) are used as building materials;

2) carbonate, which is associated with deposits of limonites, manganese carbonate-oxide ores, deposits of bauxites and phosphorites;

3) chamosite with silicate ores of iron and manganese;

4) siliceous or jasper with poor ferromanganese mineralization;

5) bituminous or slate, composed of slates with an increased amount organic matter and scattered ore mineralization (U, V, Fe, Cu, Zn, Mo, Au, etc.).

II. middle stage
(folded, preorogenic)

falls on the period of the main phases of folding. There is a change of modes of subsidence by uplift in the form of a central uplift.

Large batholiths of granitoids of two formations are formed

1) moderately acid granitoids, they are characterized by skarn deposits of scheelite and hydrothermal deposits of gold, copper, and molybdenum;

2) normal and extremely acidic granites, they are associated with pegmatite and albitite-greisen deposits of tin, tungsten, tantalum, niobium, lithium, and beryllium

Two sedimentary formations are formed

1) flysch used as building materials;

2) caustobiolitic containing oil shale, coal, bituminous and oil-bearing rock facies.

III. Late stage
(postfold)

fixes the transition of the mobile complex into a young platform, dissected by faults.

Two igneous formations are formed

1) hypabyssal intrusions in composition from diorite porphyry to granite porphyry, which are associated with plutonogenic hydrothermal deposits of ores of non-ferrous, rare, radioactive and noble metals, as well as skarn deposits of lead-zinc, tungsten-molybdenum, tin-tungsten;

2) terrestrial volcanic rocks of andesite-dacitic composition with which volcanogenic deposits of complex composition are associated.

Four sedimentary rock formations are associated with the late stage

1) molasse formation, with which deposits of building materials are associated;

2) variegated formation with its sedimentary-infiltration deposits of iron, copper, vanadium, uranium;

3) evaporite formation with salt deposits, sometimes accompanied by oil and gas formations;

4) hydrocarbon containing sand-clay formation(coal-bearing and oil-and-gas bearing subformations).

Tectonic-metallogenic zones of geosynclines

Median massifs are blocks of ancient rocks. Intrusions of leucocratic granites with pegmatite, albitite-greisen and hydrothermal deposits are localized within them.

Inner zones fix the most deflected areas where thick strata of terrigenous-volcanogenic rocks accumulate. In the middle stage, an axial uplift occurs here and granitoid complexes are introduced with their characteristic pegmatite, albitite-greisen and hydrothermal deposits of rare metals.

Geosynclinal ditches are narrow longitudinal rift structures within which volcanogenic basalt-liparitic formations (ophiolite belts) with pyrite deposits of copper, zinc and lead develop. In addition, plagiogranite-syenite formations with skarn iron ore, copper and cobalt ores are formed here.

Peripheral zones cover the marginal parts of geosynclines. These zones are intruded by batholithic masses of granitoids with plutonogenic hydrothermal deposits of gold, copper, molybdenum, lead, and zinc, as well as moderately acidic hypabyssal intrusions with skarn scheelite deposits.

forward deflections appear at the final late stage, they are made up of terrigenous, variegated, and evaporite strata; deposits of rock and potassium salts, sedimentary-infiltration ores of uranium, vanadium, and copper, as well as large deposits of oil and gas are associated with them. Sometimes, on the site of such troughs, terrestrial marginal volcanic belts of andesite-dacitic composition with hydrothermal deposits of non-ferrous, rare, and noble metals appear.

platform frame determines the width of the geosyncline and ranges from 35 to 65 km.

Border deep faults delimit the tectonic-metallogenic zones of the geosyncline and control the belts of igneous rocks and endogenous deposits. At an early stage, rocks of peridotite and gabbro formations with deposits of chromites, titanomagnetites, and platinoids are localized here. At a later stage, they are associated with small intrusions and volcanic andesite-dacitic rocks with a wide range of hydrothermal deposits.

Platform fields

In the structure of ancient platforms, three rock complexes with their corresponding groups of deposits are distinguished:

1 - base or lower tier, pre-Paleozoic foundation;

2 – cover or upper layer of platform sedimentary rocks;

3 – areas of tectonic-magmatic activation.

Lower Metamorphic Stage
It is composed of metamorphic rocks of the Archean, Proterozoic and Riphean.

It is characterized by:

1) basaltoid formations with magmatic deposits of chromites, titanomagnetites, sulfide copper-nickel ores, hydrothermal ores of gold and pyrite deposits;

2) granite formations with deposits of mica and rare metal pegmatites;

3) metamorphosed deposits sedimentary series - ferruginous quartzites, ore-bearing conglomerates and black shales, ancient stratiform formations of copper, lead and zinc.

Upper tier of platform covers characterized by a series of continental formations

It is characterized by:

1) sand-clay formation with deposits of coal, bauxite, iron and manganese ores, refractory clays;

2) bituminous formation black shale, turning into oil shale and source rocks;

3) quartz-sand formation quartz and quartz-glauconite sands, containing deposits of phosphorites and sands;

4) carbonate formations with deposits of limestone, dolomite, marl and gypsum.

In the process of formation of the platform cover, three igneous formations were formed in addition to sedimentary ones:

1) trap with deposits of copper-nickel ores, native copper, Icelandic spar, graphite and chrysotile asbestos;

2) alkaline ultrabasic and trachybasaltic , which are associated with deposits of carbonatite rare earths, phosphorus, uranium, fluorite;

3) nepheline syenites with deposits of apatite and rare earths; diamondiferous kimberlites and lamproites.

Areas of tectonic-magmatic activation

These areas are associated with manifestations of superimposed tectonic movements, which were accompanied by volcanism, intrusions of ultrabasic, alkaline, and acidic composition. These processes are associated with the formation of magmatic deposits of copper-nickel, chromite, platinoid and titanium ores in association with mafic-hyperbasic rocks, metamorphogenic rare-metal and mica pegmatites, a wide range of hydrothermal deposits of Sn, W, Mo, Au, U, fluorite, stratiform lead-zinc deposits, diamondiferous kimberlites.

Ocean deposits

Coastal-marine placers. At present, ilmenite-rutile-zircon-monazite placers of the Indian and Atlantic oceans, gold-bearing and platinum-bearing placers of Alaska and the Philippines, and South African diamonds are of industrial interest. The flooded beaches of the sea coasts (quartz glass sands, cement sands, black sands with iron and titanium ores) are of great importance.

Deposits formed at the bottom of the seas and oceans. These include deposits of phosphorites, iron-manganese nodules and sulfide ores.

Geological conditions for the formation of deposits from the standpoint of the mobilist concept

The basis of the mobilist concept is the Wilson orogenic cycle, which usually covers a time interval of 200-250 million years. The cycle is divided into five stages:

1. intracontinental rifting;

2. expansion of the ocean floor;

3. absorption of oceanic crust, collision of lithospheric plates;

4. final (stabilization).

I. Stage of intracontinental rifting

The following types of deposits are associated with the geological structures that emerged at this stage.

1. In intercontinental rifts brines and metal-bearing sediments with copper, zinc, silver, etc. (depressions of the Red Sea).

2. In rift zones of the continents basic-ultrabasic layered intrusions are formed with copper-nickel, platinoid, chromite and titanomagnetite deposits (Bushveld, South Africa; Great Dike, Zimbabwe).

3. In zones of tectonomagmatic activation the pre-rift stage produces diamond-bearing kimberlites and lamproite pipes (South Africa, Yakutia, Australia); ultramafic-alkaline intrusions with carbonatites (Kovdorskoye in Russia, South African deposits); intrusions of nepheline syenites with apatite-nepheline and rare earth mineralization (Khibiny, Russia); intrusions of alkaline granites with tin-tungsten greisens and tantalum-niobium vein deposits (Jos, Nigeria).

4. During inland rifts stratiform polymetallic ores are formed in terrigenous sequences (Sullivan, Canada; Mount Isa, Australia); roll-type uranium deposits; in evaporite complexes deposits of salts, magnesite, phosphorite.

II. Expansion (spreading) of the ocean floor

In this stage, mid-ocean ridges appear, which are deep splits in the lithosphere, mineral deposits are formed in the following geological situations.

1. In mid-ocean ridge regions on their slopes and in axial rifts volcanogenic-sedimentary pyrite-polymetallic deposits are formed.

2. In deep zones of ocean ridges chromites are formed in dunite complexes, nickel, titanomagnetite, gold ore and platinoid ores are formed in peridotite massifs.

3. In transform fault zones stratiform barite and volcanogenic-sedimentary pyrite-polymetallic deposits are formed.

4. On passive margins of continents, dissected by rifts, a sedimentary series accumulates, including stratiform copper ores, phosphorite packs; in the carbonate deposits of the shelf there are bedded lead-zinc and barite-fluorite deposits.

III. Absorption (subduction) of an oceanic plate

1. During outer arc and deep sea trenches deposits of the ophiolite association that arose earlier are brought to the surface - pyrite deposits, chromite, talc, asbestos and magnesite in ultrabasic rocks, low-temperature gold-quartz veins are formed.

2. In the volcano-plutonic arc granodiorite and granitic plutons are located, they are associated with copper-molybdenum porphyry and tin-tungsten deposits, stratified manifestations of antimony and mercury.

3. In geodynamic setting of the back-arc magmatic fields are formed by intrusions of anatectic granites with tin deposits.

4. Marginal compression basin completes the system of meridional geological structures. It is filled with terrigenous sediments and contains infiltration uranium mineralization in sandstones, salt deposits in evaporite strata, and coal seams.

IV. Collision in the "continent - continent" and "continent - arc" systems

The convergence of the continents leads to the closure of the ocean, the emergence of the foreland thrust belt, in which granites with tin-tungsten deposits, leucocratic granites, containing uranium mineralization. In the foreland basins, copper and uranium infiltration deposits are formed in terrigenous strata.

The collision of the continent - volcanic arc is accompanied by the thrusting of ophiolites on the continental foreland, while pyrite-polymetallic deposits are raised to the surface. The hinterland and foreland basins accumulate sediments with stratiform deposits of copper, vanadium-uranium ores, evaporite strata and coal formations. In the foreland thrust belt, anatectic granites occur with deposits of tin, tungsten, uranium, and sometimes silver, nickel, and cobalt.

V. Final stage.

This stage completes the cycle. It is characterized by the return of a single continent to its original state, the attenuation of tectonic and magmatic processes, the formation of amagmatic rift systems filled with terrigenous-carbonate sediments with sedimentogenic deposits and epithermal polymetallic deposits, as well as infiltration uranium ores. At this stage, volcanic belts appear with gold-silver and polymetallic deposits.

The stages of the Wilson cycle and the stages of the geosynclinal cycle of V.I. Smirnov are closely interconnected. The early geosynclinal stage corresponds to the three stages of Wilson - intracontinental rifting, expansion of the ocean floor, absorption of the oceanic crust. The middle stage is identical to the stage of collision of lithospheric plates, and the late stage is similar to the final stage of the mobilistic cycle.

The geosynclinal concept represents a fundamental empirical generalization. It gives a real picture of the earth's crust, simplifying some geological phenomena. Its main drawback is the lack of a satisfactory explanation of the metallogeny of two types of sharply contrasting structures of the earth's crust - oceanic and continental plates. It does not provide a satisfactory explanation of the magmatism and metallogeny of such structures as mid-ocean ridges, active and passive continental margins, or the causes of horizontal tectonic movements.

The mobilist concept more objectively and fully describes the origin and metallogeny of the main structures of the earth's crust. However, this concept is still far from perfect. More thoroughly positive aspects of these concepts and their shortcomings are considered in the course "Geotectonics".

Duration of deposits formation

The time of formation of deposits is quite commensurate with the duration of geological processes and, above all, the time of formation of rocks. Direct determinations of the absolute age indicate that ore formation can proceed, depending on the genetic nature and stability of ore-metallogenic processes, from thousands to tens of millions of years. In short periods of time up to tens of thousands of years, vein and stockwork deposits appear, associated with granitoid magmatism. Longer epochs (5–10 Ma) are necessary for the formation of sedimentary iron ore beds or ore complexes of layered ultramafic massifs.

Deposit Depth Levels

near-surface Place of Birth are represented by all types of exogenous accumulations, volcanogenic and exhalation-sedimentary ores. Their formation proceeded in an environment of abundance of oxygen, low pressures and temperatures. Ores are characterized by collomorphic and fine-grained aggregates.

Hypabyssal level richest in the variety of ore formations. Almost all industrial-genetic types of endogenous deposits are localized here. This is an area of ​​predominant development of hydrothermal, skarn and magmatic accumulations of minerals in layered intrusions.

abyssal zone poor in ore formations. Here, mainly albitite-greisen, carbonatite, pegmatite and some igneous deposits associated with large granitoid, basic and ultrabasic plutons are formed.

AT ultraabyssal zone a small group of metamorphic deposits is formed (disthene, sillimanite and andalusite schists, rutile, corundum, etc.). In addition, there are significant transformations of ore formed at higher levels, primarily metamorphosed deposits of iron and manganese.

Thus, in the upper shell of the earth's crust with a thickness of about 15 km (ore sphere), the concentration of minerals is most significant at the near-surface and hypabyssal levels. Below, the intensity of ore formation decreases and practically stops in the ultraabyssal zone.

Edition: Nedra, Moscow, 1986, 358 pages, UDC: 553.3

Language(s) Russian

Industrial types of deposits of ferrous, nonferrous, precious, radioactive and rare metals in various regions of the world are considered. It is based on the industrial taxonomy of deposits, based on the morphology of ore bodies, the geological conditions of their occurrence, the mineral and material composition of ores, and the features of their technological processing. The most interesting deposits are characterized Soviet Union and foreign countries. For each metal, properties and applications, geochemical features, industrial minerals and types of ores are given. For students of mining and geological universities studying the course "Industrial types of ore deposits".

Resolutions of the Central Committee of the CPSU and the Council of Ministers of the USSR drew attention to the need to intensify work on saving and rational use mineral raw materials, fuel and energy and other material resources. In light of these decisions importance acquires the study of economic issues. The Ministry of Higher and Secondary Specialized Education of the USSR was asked to intensify work on the education of students, improve the teaching of economic disciplines, and increase the role of the educational process in the economic education of students.

The economic preparation of students in the specialty 0101 (geological survey, prospecting and exploration of mineral deposits) is largely determined by the content and teaching methods of the course of industrial types of ore deposits. Essentially, it is a course in economic geology. It can be taught in a variety of ways.

The first is that the study of industrial deposits of each metal is carried out according to the genetic principle. Magmatic, pegmatite, carbonatite, postmagmatic, exogenous, metamorphogenic deposits are considered. Industrial types of deposits are considered as ore formations within genetic types. This approach to the study of the subject provides a higher level of training for specialists in the search for ore deposits.

The second way is that students study the main industrial types of deposits in order of their industrial importance, regardless of genesis. In this case, the student's interest in the economics of mineral resources develops, as it becomes a determining factor, the student masters the basics of the economic evaluation of deposits. In this case, a close connection between the courses of ore deposits and exploration is ensured, and, consequently, a higher level of training of geologists specializing in exploration of deposits is provided.

In this book, the presentation of materials is carried out along the second path based on many years of experience in teaching the course of ore deposits by prof. E. E. Zakharov and Assoc. P. D. Yakovlev at the Department of Minerals, Moscow State Institute of Natural Resources. S. Ordzhonikidze. It describes the main industrial types of deposits of 43 metals or groups of metals: ferrous, alloying, non-ferrous, noble, radioactive and rare. The names of many industrial types are preserved by traditional, long-established ones (copper-porphyry, pyrite, stratiform lead-zinc in carbonate rocks etc.). The name of a number of industrial types of deposits of tin, gold, uranium, beryllium and other metals has been specified. In this case, the type name includes the metal, the main industrial minerals (or association of minerals), and the morphology of the ore bodies. For complex deposits, minor metals are listed first, and the metal of primary importance is named last. In the process of learning, students' attention is focused on the main industrial types, on large and unique deposits, which are the main sources of metals. Deposits of secondary industrial importance and potential sources of metals are studied less thoroughly.

Throughout the history of mankind, people have mastered various minerals, especially metals. Seven of them, known since ancient times - gold, silver, copper, tin, iron, lead and mercury - are commonly called prehistoric. The first to become known to man the metal was gold. It was used to make jewelry and coins. Then people began to use copper, the role of which in the development of human culture is special. The first metal tools of labor were made from native copper, as a result, the Stone Age was replaced by the Copper Age. The use of tin and the production of bronze led to the Bronze Age. Then came the age of iron, which continues to this day. As science and technology develop, new elements are discovered, and steels and alloys are created, an increasing number of metals are used. At present, the extraction of ores of iron, manganese, aluminum, copper, lead, zinc, nickel, etc. is carried out on a huge scale. In the modern era of the scientific and technological revolution, in the era of electronics, nuclear energy, nuclear and space technology, radioactive and rare metals. But the prospects for their consumption in the future are even more grandiose. Under the conditions of developed socialism and the construction of the material and technical base of communism in our country, the role of metallic minerals has immeasurably increased. The implementation of the main strategic line in the policy of the CPSU - the maximum increase in the standard of living of the Soviet people - is possible only if there is a reliable mineral and raw material base of metals, an increase in their extraction and production. A huge amount of work has been done by Soviet geologists. Academicians V. A. Obruchev, A. E. Fersman, S. S. Smirnov, A. N. Zavaritsky, A. G. Betekhtin made a great contribution to the development of the science of ore deposits and the creation of a reliable raw material base of metals in our country , D. S. Korzhinsky, V. I. Smirnov.V. M. Kreiter (1960), and after him V.I. Krasnikov (1965) under the industrial types of deposits understood such natural geological and mineralogical types of deposits, during the operation of which, in total, several percent of this type is extracted all over the world minerals. Over the past 10 years, the industrial taxonomy of deposits has been considered by many researchers. But the most successful industrial types of ore deposits were identified and systematized by the employees of VIEMS for iron, chromites, nickel and cobalt, tungsten, molybdenum, copper, lead and zinc, tin, antimony and mercury, beryllium and other metals. The systematics of industrial types for many metals is not developed enough and should be improved in the future. When developing systematics, it is necessary to proceed from the fact that industrial deposits are those with balance reserves that are economically feasible to develop with the current state of technology. The industrial type of deposits is determined primarily by the geological conditions of occurrence and morphology of ore bodies, the mineral and material composition of ores, which determine the methods of mining deposits and the technology for obtaining metals. Depending on the amount of metal reserves, deposits are divided into large and unique, medium and small. World practice shows that large deposits play a major role in explored reserves and mining of metals. So, for example, only 6% of the total number of explored copper deposits contain 70% of the reserves of this metal, 8.3% of tin deposits - 69% of reserves, 6% of lead and zinc deposits - respectively 51 and 42% of reserves, etc. With the scale of mineral extraction projected for the near future, small and medium-sized deposits cannot significantly affect the state of supply for the growing needs of the national economy. The efficiency of their exploration and development depends on the scale of deposits. Therefore, it is desirable that the deposits discovered and explored in new ore regions be large. The quality of the ores must meet the established requirements for the content of the main metal (condition) and the permissible content of harmful elements. It is also necessary to take into account the presence of valuable impurity elements in the ore. Ores can be monometallic and complex (two-, three-metal and more). According to the content of the main components, they are distinguished among the rich, middle and poor. The most valuable are rich ores, from which metal can be obtained without preliminary enrichment. However, in connection with the growth in the extraction of metals and the improvement of methods of technological processing, poor ores are mined on an increasing scale. The technology for processing ores is determined by their mineral and material composition. It is necessary to establish the quantitative mineral composition of ores and identify the main and associated components, determine the main ore minerals, study the varieties and generations of ore minerals that differ in composition and concentration. It is also necessary to study the spatial distribution of ore minerals and draw up mineralogical and technological maps, compare the balance of the distribution of ore elements by minerals and find out the forms of their inclusion in the composition of ores, study hypergene changes in ores and solve a number of other issues. Only after this should a scheme for the technological processing of ores be developed, which should provide for the extraction of not only the main, but also associated components. Currently, 10-15 elements are extracted from sulfide copper-nickel and pyrite-polymetallic ores. Ores of rare metals are the most difficult to process. It is important not only to extract all the elements from the ore, but to extract them economically. Mining and geological operating conditions must also ensure cost-effective and highly efficient mining of deposits. The most efficient development of deposits open way, specific gravity which is increasing more and more, especially in the extraction of ores of iron, nickel, molybdenum, tungsten, tin, uranium, and some rare metals. In a number of cases, in the extraction of uranium, copper, underground leaching methods turn out to be effective. In a complex geological or hydrogeological environment, even large deposits with a high content of metals are inaccessible for mining. However, with the improvement of technology, these issues are successfully resolved. The geographical and economic position of the deposits also, in some cases, has a significant impact on their economic evaluation. An industrial deposit must meet the following requirements: have large reserves, have ores High Quality, well amenable to processing, be characterized by mining and geological conditions available for efficient mining, and, finally, be located in a favorable geographical and economic region. However, with the development of science and technology, especially in the age of the scientific and technological revolution, all these requirements do not remain constant, the concept of industrial deposits. All new deposits, which until recently were considered non-industrial, are involved in mining.

This chapter deals with the morphological features of the deposits, i.e., their shapes and sizes, the spatial orientation of bodies among the host rocks, and post-ore disturbances.

A correct understanding of the morphology of mineral deposits and the conditions of occurrence of ore bodies is important, first of all, in the preparation of projects for the rational exploitation of deposits. Therefore, the study of the form and conditions of occurrence of ore bodies is one of the important tasks in carrying out detailed and operational exploration of deposits. The correct solution of this issue is also important in determining the genesis of the explored deposit, which, in turn, predetermines the exploration plan.

1. Syngenetic and epigenetic deposits

According to the relative age of mineral deposits and their host rocks, two groups of deposits are distinguished: syngenetic and epigenetic. The former are formed simultaneously with the host rocks as a result of the same geological process. Typical representatives of such deposits are seam deposits of coal, fossil salts, bauxites, occurring among layers of sedimentary rocks and formed simultaneously with them in the same process of sedimentation or sedimentation (sedimentary deposits). Epigenetic deposits appear later than those rocks among which they occur; the formation of deposits and host rocks occurs in this case as a result of various geological processes. Characteristic examples of epigenetic deposits are vein ore bodies of postmagmatic genesis occurring in fissures developed in various rocks.

2. Shapes of bodies of minerals

Each geological body has three dimensions in space (length, width, depth); depending on the ratio of the values ​​of these three dimensions, there are trn types of forms of minerals:

1) body isometric, having approximately equal three dimensions;

2) columnar bodies, in which one size is large compared to the other two - the elongation in depth is large, and the length and width are much smaller;

3) body stock-shaped, in which two dimensions are large (extension in depth and length), and the third (power) is small.

Between these three types there are transitional forms. In addition, in nature there are such forms of deposits that cannot be put into any of the above types, for example, a collection of small accumulations of mineral matter. These irregular forms of deposits stand out in a special fourth type - complex bodies.

The classification of the shapes of the bodies of mineral deposits is presented in Table. one.

Isometric shapes bodies of mineral deposits are not widely distributed. stem and socket differ from each other in size. The size of the rod in diameter is determined by at least tens of meters. The diameter of the nest is measured in several meters. Nests of chromites and platinum-bearing chromites in ultramafic rocks (Nizhne-Tagilskoe deposit in the Urals) can serve as examples of syngenetic deposits of isometric shape. Epigenetic deposits are characterized by both stock-like and nest-like forms of ore bodies, but still nests predominate. For example, nest-like bodies of lead-zinc ores are often found in limestones, which arose in a metasomatic way (Nerchinsk deposits in Transbaikalia). stock a large more or less isometric deposit of continuous or almost continuous mineral raw materials is called (Fig. 1).

Rice. 1. A stock of copper ore from the Tsitelsoneli deposit. 1 - Quaternary loose deposits; 2- Quaternary lava; 3 - Upper Cretaceous tuffs; 4 - gypsum tuffs; 5 - secondary quartzites; 6- dikes of quartz albitophyres; 7 - ore body; 8 - boreholes.

An example is rock salt stocks, hydrothermal metasomatic ore deposits, etc.

When the stem or socket is flattened in one direction and there is a transition from these bodies to plate-like, lenses and lentils appear. Unlike isometric bodies, the lens has unequal power: its power is maximum in the center, and it disappears towards the edges. A lentil differs from a lens in its relatively greater power but smaller overall dimensions.

nest a relatively small local accumulation of a mineral is called. These include the bodies of some deposits of gold, lead-zinc, chromite, mercury and other ores.

Columnar bodies always epigenetic. They are relatively rare. Their characteristic representatives are pipes and pillar-like veins. Pipes have an elliptical or rounded section, measured hundreds of meters across, and sometimes they extend to a depth of several kilometers. Classical examples of tubular bodies lying almost vertically are igneous diamond deposits in Yakutia and South Africa, confined to intrusions of ultrabasic rocks, kimberlites, corresponding in shape. Columnar bodies are also found among ore postmagmatic deposits: Klimeks (Mo) in the state of Colorado and Deposits in Russia - Angaro-Ilimskoe and Mikoyanovskoe. Columnar veins have a small length in horizontal section and not significant thickness, but vertically they can be traced for hundreds of meters, and sometimes more than a kilometer.

The main element that determines the size and shape of isometric bodies is their cross section.

Flat bodies of minerals characterized by two long and one short size. Their most characteristic representatives will be: for epigenetic deposits - a vein, for syngenetic deposits - a layer.

Plast is a plate-like body of sedimentary origin, having a homogeneous composition and limited by two more or less parallel (except for pinches) bedding surfaces. The formations usually occupy a large area: they are elongated along strike and dip for hundreds and thousands of meters, having a relatively small thickness, measured in meters, less often tens of meters. In undisturbed geological sections, the underlying mineral layer is older, and the overburden is younger than the layer located between them. Layers, like veins, have constrictions and bulges, can thin out and wedge out.

Layered deposits of many minerals are known: manganese ores (Nikopolskoye), phosphorites (Karatausskoye), salts (Solikamskoye), coals (Donbass, Irkutsk basin), etc.

Layers are most typical for sedimentary deposits of ore, coal and non-metallic minerals. Metasomatic bodies developing along separate layers of sedimentary rock strata acquire the character layered deposits. The mineral layer is sometimes divided into packs separated by rock interlayers; packs, in turn, can break up into layers. Accordingly, the layers are distinguished simple(without rock layers) and complex(with rock interlayers).

Rice. 3. The structure of the mineral layer (in the section). 1 - bundles and layers of minerals; 2 - rock layers

The main elements that determine the geological position and dimensions of the formations are strike direction and strike length, dip direction, dip angle and dip length, and, finally, formation thickness. Usually reservoir deposits have a large length, reaching, for example, in the Donets Basin, several tens of kilometers. By dip, some formations, such as the gold-bearing Witwatersrand conglometers in South Africa, are mined to depths of more than 3 km. The formations are divided into steeply dipping, with dip angles of more than 45 °, and gently dipping, with angles of incidence less than 45°. The thickness of the mineral deposits varies from barely noticeable interlayers to several hundred meters. So, for example, the thickness of working coal seams in the Donbass is usually 0.45-2.5 m (average 0.7 m), the thickness of brown coal seams of the tertiary basins of the Southern Urals reaches 150 m, and the thickness of the salt deposit in Solikamsk in the Urals is 500 m.

Thin seams of minerals are not mined. Therefore, in addition to the geological definition of thickness, there are industrial concepts of the thickness of mineral deposits. Working the minimum thickness at which the formation is expedient to exploit is considered. For coal, it ranges from 0.1 to 1 m. is the total thickness of the mineral and rock layers for the working part of the reservoir. Useful power is defined as the sum of the power packs of minerals, extracted during production from the reservoir.

Deposits of reservoir form are single-layer and multi-layer. In the latter case, it stands out productive stratum rocks, enclosing a series of layers of minerals. The number of such layers in the productive stratum can be different. So, in the Moscow Region basin there are only two working layers, in the Donbass - about 100, in the Upper Silesian basin - 140. The richness of the productive strata is determined by productivity factor- the ratio of the total thickness of mineral layers to the total thickness of the stratum.

Residential It is customary to call a body formed as a result of filling a crack in any rocks with a mineral substance.

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Rice. 4. Feathered vein and scheme of tectonic movement along the vein shaft

In the event that the vein has not a vertical, but an oblique fall, the rocks that lie above the vein are called the hanging side, and the rocks that lie under the vein are called the recumbent side of the vein. The surface along which the vein mineral substance comes into contact with the side rock is called the selvage. Lives varied in size. Their length is measured in tens of meters, the first hundreds of meters, less often kilometers, and sometimes tens of kilometers. The longest gold-bearing Mother Vein in California has been traced intermittently for 112 km.

Rice. 5. Veins.

a - simple; 6- complex. Dots cover the area of ​​unaltered wall rocks

The thickness of the veins varies from tenths of a meter to tens of meters. Along the dip, the veins sometimes wedge out rather quickly, but they can extend to a considerable depth, exceeding a kilometer. For example, the gold-quartz veins of the Kolar deposit in India were exposed to a depth of about 3 km.

The power of the veins rarely remains constant; usually, however, it varies both along the strike and along the dip of the vein, sometimes increasing in places of swelling, then decreasing in places of constrictions. Lived; characterized by bloat, following one after another, is called cicatricial th or chamber. If these bulges are close to each other, the vein is considered beaded.

Rice. 6. Beaded vein x Fig. 7. Chamber vein

Wedging of veins can be simple, blunt and complex. With a simple wedging out, the power of the core gradually decreases down to zero. With a blunt wedging out, the power of the core is abruptly cut off. With complex wedging, the veins are divided into a number of separate protrusions, or so-called fingers. Such complex wedging is very typical, for example, for pegmatite veins of the Mamsky mica-bearing region.

veins can be located in various ways among the host rocks. In accordance with this, bedded veins are distinguished, which occur in accordance with the stratification of rocks, and secant veins, which are located inconsistently with the stratification or schistosity of the host rocks. As noted earlier, the veins that lie in the cavities of the exfoliation of anticlines are called saddle veins. Their classical representative is the system saddle lived in the Bendigo gold deposit in Australia (see Fig. 8).

Rice. 8. Saddle vein

complex shapes ore bodies are widespread. They occur mainly among epigenetic deposits. Sometimes complexly built reservoir bodies are observed in syngenetic deposits.

In this case, there is an alternation of mineral interlayers with interlayers of waste rock. For example, the layer of the Chiatura manganese deposit is divided into 10-15 ore and non-ore layers. Among the epigenetic deposits of complex shape, which appeared in most cases in combined structures, stockworks and complex veins are the most common.

Stockwork consists of a network of intersecting small ore veins and veinlets, accompanied by impregnation of ore minerals; general form distribution of such vein-disseminated mineralization is irregular, sometimes isometric or elongated and resembles a fractured mineralized zone (see Fig. 9). Stockworks are characteristic of many hydrothermal deposits of tin, gold, copper, molybdenum, tungsten, beryllium, etc.

Rice. 9 Schematic section of the stockwork Altenberg deposit;

1 - granite-porphyry: 2 - stockwork in greisenized granite; 3 - host rocks along ruptures (and cleavage) in granite-porphyry dikes

Complex veins are quite diverse in their structure. Contiguous parallel veins predominate among them, and, in addition, branching veins, leafing veins and reticulate veins stand out.

branching vein It is characterized by the presence of numerous branches, the so-called apophyses, extending from the main ore vein towards the recumbent and hanging sides. Similar body shapes are characteristic of many deposits of mica-bearing and rare-metal pegmatites.

leaf vein is a system of veins, veinlets, lenses and lentils formed as a result of the execution of a complex network of thin more or less parallel cracks by mineralized solutions, confined to the shear zone (Fig. 10). An example of a deposit with such complex bodies is the hydrothermal Klyuchevskoye copper-cobalt deposit in the Urals. In the event that small veins in an elongated shearing zone are oriented in different directions, a complex vein is called mesh. All the mentioned ore bodies can either come to the surface or be located at a depth without reaching the surface. In the latter case, they are called "blind" or "hidden" bodies.

The contact surface of the vein with the host rocks is called selvedge. The rocks adjacent to the vein are often altered and mineralized; such zones of metamorphosed wall rocks create halo periveinal change, sometimes containing industrial concentrations of valuable components. The veinlets extending from the veins into the side rocks are called apophyses. The main geological elements that determine the size and conditions of occurrence of the veins are the strike direction and strike length, direction, dip angle and dip length, declination, and thickness. The length of the veins of minerals varies over a very wide range, from short veins measuring 1 m or less to a colossal length of 200 km (for example, the Mother vein of gold ores in California).

Veins, as well as layers, are divided into steep (more than 45°) and gently dipping (less than 45°). By dip, some veins wedge out shallowly from the earth's surface, while others, such as the Sadonskaya vein of lead-zinc ores in the Caucasus, can be traced at a distance of more than 1.5 km; the Kolar gold-bearing quartz veins in India are mined at a depth of over 3.2 km. declination called dipping lines; wedging out of the vein along its strike; declination angles - the angles formed by the lines of declination with the line of strike. In veins, as well as in strata, a distinction is made between geological and working capacity, i.e., its smallest value at which the exploitation of a vein deposit becomes possible.

Vein deposits sometimes consist of one vein, and more often of groups - bundles or families of veins. Ore fields formed by vein deposits are called vein fields.

Lenses and lenticular deposits morphologically, they belong to formations that are transitional between isometric and flat bodies.

The bodies of minerals elongated along one axis are called pipes, tubes, or tubular deposits. The morphology and conditions of their occurrence are determined by the angle of immersion, or diving, the length in the direction of immersion and the cross section. Diving angle tube mineral is measured between its axis and the horizontal plane. It can vary widely: from 90° for vertical pipes to 0° for horizontal tubular deposits. The cross section and axial length of the pipes are also quite variable. For example, the cross section of diamond-bearing kimberlite pipes in Siberia ranges from 100 to 1000 m.

Among deposits of liquid and gaseous minerals(oil, water, combustible gas), in accordance with the classification of I. Brod and N. Eremenko, according to morphological features, reservoir, massive and lenticular deposits can be distinguished.

Reservoir deposits liquid and gaseous minerals are confined to a reservoir of permeable rocks, enclosed among impermeable or low permeable layers, to some extent tectonically dislocated. Such deposits are usually the largest, reaching more than 80 km in length along strike and up to 70 km in width.

massive deposits are accumulations of liquid or gas in ledges of permeable rocks (structural, erosive, reef), overlain by poorly permeable sediments. They can be both small and large in size, reaching 50 km 3 (Achaluki-Karabulak) and even several hundred cubic kilometers (Majid Suleiman in Iran, Kirkuk in Iraq, Abqaiq in Saudi Arabia, etc.).

Lenticular deposits associated with local zones of porous and fractured rocks, bounded on all sides by impermeable rocks.