Geology

Primary Energy The source of energy which does not require any transformation before the use is called primary energy. They are directly used as they available in nature. E.g. sun, river water, mountain lakes, wind, coal, crude oil, natural gas, wood, uranium, geothermal heat etc.  Secondary Energy The source which requires transformation before the use is called secondary energy. E.g. Petrol, diesel, kerosene, charcoal, electricity etc. The petrol, diesel and kerosene are derived from the petroleum (crude oil), charcoal derived from the wood, electricity derived from the water, wind, coal and also from the sun.

Dip The angle of inclination of a bed with respect to horizontal plane is called amount of dip measured at right angle to strike. The direction along which inclination of a bed occurs is the direction of dip. It has amount (magnitude) as well as direction so it is a vector quantity.  The amount of dip varies from 0° to 90° . Types of dip i)  True dip When the dip is measured along the right angle to the strike it is called true dip. It has always maximum amount of dip between 0° to 90°. ii) Apparent dip Along any direction other than true dip is the apparent dip. It is always less than true dip. Strike It is the direction of the line of intersection between the bedding plane and the horizontal plane. It has only direction so it is scalar quantity.  It is horizontal line on the bedding plane. It has always right angle relationship with the direction of true dip.

An ore deposit is an volume of rock enriched in one or more minerals of economic importance. Classification of ore deposits on the basis of genesis and mode of occurrences are mainly - 1. Magmatic ore deposits 2. Hydrothermal ore deposits 3. Sedimentary ore deposits 4. Supergene sulphide enrichment 5. Metamorphic ore deposits 1. Magmatic ore deposits These are generated through the process of magmatic intrusions. The economic minerals accumulate to form magmatic ore deposits. It is further subdivided into - i) Magmatic segregation  Fractional crystallization of cooling magic magma leading to development of oxides and silicates. Segregation is a general term refering to any process by which one or more minerals become locally concentrated during cooling and crystallization of magma. Eg. Pt, Fe, Ni, Cr, Ti, V deposits. ii) Pegmatitic deposits These deposits generally occur in association with granites. Pegmatites are very large single crystals. Eg. Mica formed when magma ...

There are mainly two types of energy 1. Renewable Energy 2. Non Renewable Energy 1. Renewable Energy It includes solar, wind, hydropower, geothermal, biomass etc. These are also called clean energy. The renewable energy resources are displacing fossil fuels in the power sector also offering the benefits of low carbon emissions and other types of pollution. The renewable energy comes from natural sources that can be replenished. For example sun and wind keep shining and blowing, even if their availability depends on time and weather.  Renewable energy is even thought of the new technology, harnessing nature's power has long been used for heating, transportation, lighting and more. Wind energy is made when wind moves the blade on a wind tarbine. This movement creates wind energy which which is converted into electricity. The sun is providing light and warmth which can be converted into solar energy.  Types of Renewable energy A) Solar energy Sun is a powerful source ...

Introduction In all silicates the silicon atoms are in four fold coordination with oxygen. This arrangement appears to be universal in these compounds and the bonds between silicon and oxygen are so strong that the four oxygen are always af the corners of a tetrahedron of nearly constant dimension and regular shape. The different silicate types arise from the various ways in which these silicon-oxygen tetrahedral are related to one another whatever the rest of the structure may be like. The silicate classification is based on the following types of linkage - 1. Independent Tetrahedra Group (Nesosilicates) In this group the silicon oxygen tetrahedra are present as separate entities. The resulting composition is SiO4. The typical mineral is forsterite (olivine). This division of silicate is known as Nesosilicate. Si:O = 1:4. 2. Double Tetrahedra Structure (Sorosilicate) In this group the two silicon oxygen tetrahedra are linked by sharing of one oxygen...

Topographical Map (Toposheet) Topographical map with surface contours prepared and published by Survey of India.It is the excellent base map for geological mapping. A topographical map shows the surface features (mountains, hills, valleys, rivers, canals, lakes, swamps, wells, roads, railways, vegetation, villages, towns etc.) on a sufficiently large scale to enable the individual features to be identified on the ground by their shape and position. The scale of Indian Toposheet is 1:50000. Symbols/Legend/Key Symbols are used to represent topographic features on the map. Every map contains a symbol. Symbols are lines, polygon, points, arrow, alphabets, colours, shadings to represent different features. Point symbol It represents the location and entity or other characteristic feature of a small territorial extent to the map scale. It depends on the scale of a map. When a map is prepared on 1:1000000 scale a village may be represented as a point but on 1:10000 it can be repre...

Weathering Weathering is the process of breaking down of the rock materials through physical and chemical processes because of exposure at or near the Earth’s surface. Weathering occurs insitu or with no movement. Types of weathering 1. Physical Weathering 2. Chemical Weathering 3. Biological Weathering 1. Physical weathering Physical weathering is he process that causes disintegration of rocks without chemical changing. Physical weathering can occur due to temperature, pressure, frost action etc. Types of Physical weathering i)  Exfoliation ii) Frost Action iii) Crystal Growth i) Exfoliation It occurs due to two reasons a) Temperature variation In this case sheets of rocks split off due to differential expansion and contraction during heating and cooling regularly. b) Unloading Some times due to unloading of the overlying rocks the pressure of the igneous rocks decreases and due to which the rocks expand and a large scale fracture formed parallel to surface...

Scale Scale is the relationship between the distance on the map and distance on the Earth’s surface. A general definition of scale is that is is a ratio between the distance on a map and the corresponding distance on the Earth’s surface. Scale = Map Distance/Ground Distance  It is an important element of a map because it gives relative picture of ground reality.  Scales can be expressed in three ways- 1. Statement Scale 2. Representative Fraction 3. Linear or Graphical Scale 1. Statement  The scale may be indicated in the form of a written statement. The scale is written as 1cm to 1km. This means that 1cm on the map corresponds to 1km on the ground. This method of expressing is not very useful. 2. Representative Fraction It is also called numerical scale. It is expressed as the ratio of map distance and ground distance. For example 1:50000 means 1 unit on the map corresponds to 50000 units on the ground. The advantage of of RF is that it can be used universall...

Map Map is a tool to represent or determine deposition of any feature or any point on the earth. It is two dimensional diagrammatic representation of the whole or part of the earth and its surface features both natural or cultural at a given scale on a plane paper. How to draw a map There are various ways by which the earth can be mapped. i)  By freehand sketches and diagrams, ii) By actual survey with the help of instruments like chain and tape, theodolite, prismatic compass, plane table etc. iii) By photographs like aerial photographs or ground photographs. iv) By Satellites, Remote sensing, GPS. Digital mapping has now emerged as an important tool for mapping. On the basis of Scale  Types of maps 1. Large Scale maps 2. Medium Scale maps 3. Small Scale maps 1. Large Scale maps These maps represent small area of the earth on a large size of paper. For example Cadastral map, Topographical map. Scale is 1:10000 or less. 2. Medium Scale maps These represent relatively medium are...