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Here is a term paper on ‘Geology’. Find paragraphs, long and short paragraphs on ‘Geology’ especially written for school and college students.
Term Paper on Geology
1. Term Paper on the Introduction to Geology:
The sciences that deal with one or more aspects of the Earth as a planet are grouped together as earth sciences. All of them are definitely related to and in many cases derived from science of geology.
Geology (from Greek, Geo = Earth; logos = science) is the science that deals with the study of the Earth as a planet. Thus it includes essence of scientific studies dealing with the origin, age and structure of the Earth on the one hand and with the evolution, modification and extinction of various surface and subsurface physical features (like mountains, plateaus, plains, valleys, basins, caves and all coastal, marine and submarine forms) on the other hand.
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It also deals with the materials making up the earth, and with the nature and functioning of the surrounding gaseous envelope called atmosphere. Similarly, the study of all the water bodies existing on the surface or underground—the hydrosphere also forms an important part of geology. The interaction of the atmosphere, lithosphere and hydrosphere, including the processes involved and results produced due to such an interaction also fall in the domain of the science of geology.
Further, geology also includes the study of various physical, dynamic and physico-chemical processes operating on or within the earth and of the agents and forces involved and evolved in such processes. Geology is rightly considered as one of the fundamental basic sciences like Physics, Chemistry and Biology.
2. Term Paper on the Subdivisions of Geology:
From the above definition of geology, it is evident that the subject is very vast, hence the necessity of subdivisions.
Following are important and well-established branches of geology:
(a) Physical Geology:
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It deals with the origin, development and ultimate fate of various surface features of the Earth and also with its internal structure. The role played by internal agents (volcanism and earthquakes) and external agents (wind, water and ice) on the physical features of the earth makes major areas of study in physical geology. Similarly, the disposition of rock bodies, water bodies and huge moving deposits of ice on the surface and their structures also form important subjects of physical geology.
(b) Geomorphology:
This branch, although a part of physical geology, deals specifically with the study of surface features of the earth, primarily of the land surface. Detailed investigations regarding development and disposition of mountains, plains, plateaus, valleys and basins and various other landforms associated with them; fall in the domain of geomorphology. The structure and evolution of these landforms through space and time are advanced fields of study within geomorphology.
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(c) Mineralogy:
Minerals are the basic building units of which the solid crust of the earth is made up. Mineralogy is that branch of geology, which deals with formation, occurrence, aggregation, properties, and uses of minerals. Mineralogy is sometimes itself divided into specific sub-branches such as crystallography, optical mineralogy and descriptive mineralogy and so on. Crystallography is a well-established branch of mineralogy that deals exclusively with internal structure and external manifestations of minerals occurring in crystallized form in the natural process or made from synthetic processes.
(d) Petrology:
Minerals occurring in natural aggregated form are called rocks. These rocks form the building blocks that make up the crust of the earth. The rocks are themselves made up of minerals already defined as building units. Formation of various types of rocks, their mode of occurrence, composition, textures and structures, geological and geographical distribution on the earth are all studied under petrology.
It is one of the most important subdivisions of geology and is further subdivided into three distinct branches- Igneous petrology, Sedimentary petrology and metamorphic petrology. Petrography, another distinct branch of geology deals specifically with nature and distribution of rocks on the Earth and geological explanations governing such a distribution.
(e) Historical Geology:
It deals with the past history of the Earth as deciphered from the study of rocks and features associated with them. Rocks may be treated as pages of the Earth’s history. They contain within them enough evidence indicative of nature and time of their formation, composition, constitution, magnetism, structural disposition and in many cases, fossils (remains of ancient life), all of which when interpreted scientifically reveal a lot about the events that have passed since their formation.
Thus, fairly accurate estimates can be made from the above evidence about the climates, biological and environmental conditions prevailing just before, during and after the formation of these rocks in and around the areas of their occurrence. Paleo-geography, paleontology and stratigraphy are three distinct subdivisions of Historical Geology.
(f) Economic Geology:
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This branch deals with the study of those minerals and rocks and other materials (fuels etc.) occurring on and in the earth that can be exploited for the benefit of man. These include a wide variety of ores of all the metals and non-metals, building stones, salt deposits, fuels (coal, petroleum, natural gas and atomic minerals) and industrial minerals for refractories, abrasives and insulations and for manufacture of chemicals.
Mode of occurrence of these materials, principles involved in their formation and accumulation, their properties, structural and other controls that help in their extraction at economical costs are important fields of study under Economic Geology.
Allied Sciences:
In addition to the above major branches of geology, there are a few other comparatively new branches of science in which geology makes a very important and basic component. Their number is on the increase with advances in the science. A few of them are- geo-chemistry, geo-physics, geo-hydrology, mining geology, engineering geology, rock mechanics, geo-mechanics, meteorology and oceanography.
Their scope is briefly given below:
1. Geochemistry:
It is a branch of geological sciences dealing with chemical constitution of the Earth as a planet and also of its various parts. It studies specifically the distribution and relative abundance of different elements and their various compounds occurring on and within the earth. It also studies the trends of reorganization in the elements of earth during its geological history that has resulted through the operation of surface and subsurface processes.
2. Geophysics:
In this branch of science important principles, processes and methods of Physics are applied to solve many geological problems. Thus, the study of the internal constitution of the Earth is virtually impossible without application of knowledge of seismic waves.
In fact, there are a number of geological areas where application of principles of Physics is not only desirable but also absolutely essential, e.g.; geo-magnetism, geo-thermometry, geo-electricity, geo-cosmology and seismology. Identification of water and oil bearing strata below the surface of the Earth is carried out mostly by using geophysical principles and processes.
3. Geohydrology:
It is an engineering science that has evolved out of interaction between hydrology and geology. It deals specifically with the geological aspects of groundwater and surface water bodies with regards to their occurrence and movement through different types of rocks.
4. Mining Geology:
It is geology as applied to mining and quarrying practice, that is, for the exploration and exploitation of economic mineral deposits. The location and development of mines are decided primarily on the basis of mode of formation, mode of occurrence and structural disposition of economic mineral and rock deposits. Knowledge of mineralogy and petrology is a prerequisite for the study of mining geology.
5. Engineering Geology:
It is rather a new field of applied sciences that has developed due to interaction between the civil engineering practice and geological sciences. This branch deals with the geotechnical studies of the sites and locations for major engineering projects on the one hand and with the availability of materials of required quality for construction on the other hand.
It has very vital roles to play in the planning, design and construction of safe, stable and economic engineering projects.
6. Rock Mechanics:
It deals exclusively with study of behaviour of rocks under various types of loads imposed on them. In this respect, Rock Mechanics is more engineering rather than applied science subject. But rocks being geological materials and the behaviour of rocks being practically controlled by the nature and constitution of rocks, this branch presupposes full geological knowledge of rocks.
In rock mechanics, loads applied may be natural or artificial, static or dynamic. Similarly, measurements may be made in laboratory on representative samples or in situ conditions, i.e. at the location of proposed construction, or in all possible combination of situations. The branch also includes study of all those factors, geological or otherwise, responsible for observed and expected behaviour of rocks under different force fields.
7. Geomechanics:
It is a newly developing engineering science which concerns itself with the study of natural force fields as acting on the Earth on global and regional levels. The present structural constitution of the continents and oceans, mountain ranges and basins etc. offers a lot of scope for analysis of forces responsible for the development and disposition of these major features.
8. Meteorology:
The study of atmosphere (which is an integral part of the Earth as a planet) in all its aspects- physical, chemical and biological, falls in the exclusive domain of meteorology. Till early sixties of the twentieth century, meteorology was thought to be concerned only with weather. With dramatic advances made possible in the study of space through satellites, rockets and spaceships, meteorology has become a science of immense significance.
9. Oceanography:
This may be rightly described as the youngest of geological sciences dealing exclusively with the physical, structural, genetic and other aspects of the extensive water bodies, the oceans, which cover about 70% of the surface area of the planet. Great stress is being laid by all the big nations on the study of oceans in all respects because they offer an immense source of hitherto unknown reserves that can be explored and exploited for the benefit of mankind.
3. Term Paper on the Scope of Engineering Geology:
Engineering geology may be defined as that branch of applied sciences which deals with the application of geology for a safe, stable and economic design and construction of a civil engineering project. It is now recognized as a well-established interdisciplinary subject. In qualifying for a career as a civil engineer, grasp of fundamentals of engineering geology is almost universally considered as essential as that of soil mechanics, strength of materials or theory of structures.
Since the fifties of twentieth century, this branch has undergone very sound and rapid developments so that at present application of geological knowledge in planning, designing and construction of big civil engineering projects is considered not only desirable but also absolutely essential.
The basic objects of a course in Engineering Geology are twofold:
(a) It enables a civil engineer to understand engineering implications of certain conditions related to the area of construction, which are essentially geological in nature.
(b) It enables a geologist to understand the nature of geological information that is absolutely essential for a safe design and construction of a civil engineering project.
It is obvious, therefore, that a civil engineer is neither expected nor required to undertake himself geological investigations of the area before designing and implementing the construction plans of a major civil engineering project. He must be, however, capable to understand and critically discuss a geological report of the area prepared by an experienced geologist and derive maximum useful information pertaining to the project in question.
The scope of engineering geology is best studied with reference to major activities of the profession of a civil engineer which are – Construction, Water Resource Development, Town and Regional Planning.
Geology in Construction Jobs:
In all types of heavy construction jobs such as buildings, towers, tanks, dams and reservoirs, highways and bridges, traffic and hydropower tunnels, embankments and retaining structures, lining of irrigational and navigational canals and water bodies, laying of pipelines for oil, gas and water transport, platforms and aerodromes and so on, full geological information about the site of construction (or excavation) and about the natural materials of construction is of paramount importance.
This information has full relevance in all the three aspects of each construction:
(a) Planning
(b) Designing
(c) Execution
(a) Planning:
Following geological information is greatly useful in proper planning of an engineering project:
(i) Topographic Maps:
Such maps give details of relief features and are essential to understand relative merits and demerits of all the possible sites for the proposed structure. The presence and nature of slopes, size, contours and depths of valleys and gorges and rate of change of elevation in various directions can be easily computed from such maps. A broad choice to demarcate the area for construction can be made at this stage.
(ii) Hydrological Maps:
These maps give broad details about the distribution and geometry of the surface water channels and also the occurrence and depth contours of groundwater below the surface of the earth. Such data is of great importance in proper planning of many engineering projects. This is because surface water and groundwater are most important factors that influence the stability and cost of engineering structures in many ways.
(iii) Geological Maps:
Petrological characters and structural disposition of rock types as developed in the proposed area are depicted in geological maps. It is from these maps and sections drawn across them in different directions an engineer can obtain much useful information regarding fracturing and displacement that the site rocks might have undergone in the past.
These maps also give an idea about the availability or otherwise of the materials of construction in the area. Further, these maps guide him in locating and limiting the exploratory operations (test holes etc.) for subsurface investigations in the area of interest.
(b) Design:
In the matter of designing of an engineering project, the role of geological information can hardly be overemphasized. In many cases these are the geological characters and conditions that finally dictate the broad contours of the engineering design of an engineering project, be it a high rise building, road, bridge, dam or a tunnel and so on.
For instance, in the matter of choice between an earthen dam, a gravity dam and an arch dam, the ultimate type of dam chosen and the design of that particular type of dam would be dictated mostly by the geological conditions of the site.
The profile of the gorge or the valley, the strength of the rocks at the base and on the embankments need very thorough testing and analysis before deciding the final size, shape and other parameters of the design of the dam. Dams as high as Bhakra Dam and as long as Hirakud Dam of India cannot be built across every river valley of the world.
Some of the geological characters that have a direct or indirect bearing upon the design of a proposed project are:
i. The existence of hard bed rocks and their depth from and inclination with the surface.
ii. The mechanical properties along and across the site of the proposed project; among these properties, special mention must be made of their compressive strength, shear and transverse strength, modulus of elasticity, porosity and permeability, resistance to decay and disintegration.
iii. Presence, nature and distribution pattern of planes of structural weakness (joints, faults, folds, cleavage, schistosity and lineation etc.) and also that of seams or zones of weak materials (as shear zones, fault zones, clay bands, schistosity zones etc.).
iv. The position of groundwater table in its totality including points of recharge and discharge and variations during different periods of the year.
v. Seismic character of the area as deciphered from the seismic history and prediction about future seismicity.
(c) Execution:
During the actual execution of a civil engineering project, geological knowledge is of great value to an engineer in the selection and proper use of right type of materials of construction derived from the natural bedrocks, soils and banks and beaches.
The engineer responsible for the quality control of construction materials will derive enormous benefit from his geological background of the natural materials such as sands, gravels, crushed rocks and soils. Properties of all of these materials are best understood when studied in proper geological perspective.
Similarly, for construction in geologically sensitive areas as those of coastal belts, seismic zones, and permafrost regions, knowledge of geological history of the area is of great importance. In the coastal areas, behaviour of rocks towards waves, currents and marine environment must be fully understood both at the planning stage and more so during execution of the work.
Special type of construction may become essential in these areas. It is true about construction in seismic regions where weight of the construction material becomes a critical factor because the construction has to be well balanced and essentially light weight as far as possible.
Architectural fancies are to be avoided or else very carefully designed and constructed. Construction in permafrost regions (where soil remains permanently frozen up to a certain depth all the time), presents its own problems that can be solved only by proper understanding of the ground below.
Construction of underground projects like tunnels cannot at all be undertaken without a thorough knowledge of the geological characters and setting of the rocks and their relevance to the loads imposed on or relieved from them. The same type of rock may behave totally differently under different natural settings.
Rocks do not behave according to empirical thumb rules that may be possible for other materials because these are anisotropic in character. Hence stability of a structure constructed on them or through them or with them depends considerably on the understanding of the nature of rocks in all seriousness.
Geology in Water Resources Development:
Exploration and development of water resources have become very important areas of activity for scientists, technologists and engineers in all parts of the world. In fact water is fast becoming most sought after necessity for survival of mankind on the globe. Geological information is of fundamental importance in exploration and exploitation of water resources of a region from surface and subsurface reserves of water.
The water resource engineer has to understand the water cycle in all essential details. Water cycle is the name given to the sum-total of processes of evaporation of water from the hydrosphere, its precipitation in the form of rain and snow, and its falling and/or flowing back into the rivers, lakes, seas and oceans and into underground water bodies and soil.
Study of water cycle is an essential prerequisite for effective planning and execution of major water resource development programmes on national and regional levels. The water bearing properties of rock bodies, the aquifers as they are called, as well as host of other factors that influence storage, movement and yield of water from aquifers are essentially geological problems. They require thorough geological knowledge about the make-up and disposition of strata for designing a dependable water supply project.
In the present times a new approach for solving the scarcity of water for the human race is being considered seriously. It would involve finding out ways and means for utilizing frozen waters spread over millions of square kilometer area in mountains and in Polar Regions as glacial ice.
Glacial Geology is that branch of geology, which deals with the origin, evolution, and extinction of glaciers throughout the history of the earth. It has acquired new importance and is expected to become an area of utmost utility for the water resource engineers of near future.
The modern basin management engineer prefers a unified approach to the various problems faced by him. The various aspects of water resources and supply, conservation of water from different sources, water pollution in all its aspects and waste water disposal as also its purification and recycling for different uses are now treated in an integrated manner rather than on individual basis.
This requires a thorough knowledge of quantitative as well as qualitative parameters of geological formations and water bodies of the entire area under consideration.
Such a study would make it possible to view the surface and subsurface water reservoirs in terms of three-dimensional geological network. This network can then be operated as an integrated unit for a variety of water development programmes such as storage, supply, replenishment of reservoirs and disposal and treatment of the polluted water for recycling.
4. Term Paper on Geology in Town and Regional Planning:
A town planner is concerned essentially with land utilization in as best and as aesthetic a manner as possible for developing cities and towns for meeting social needs in different areas. In this effort, his primary aim is to derive maximum benefits from the natural environment with minimum disturbance.
To achieve these twin objectives, he must possess a broad perspective of the nature and properties of all the elements making the environment of the area under study. The materials making the land (rocks, soils, vegetation, water bodies etc.) and the roles played by each of them in the evolution of the natural landscape has to be understood.
He must be capable of fully understanding the state of equilibrium the surface features have already achieved with the prevailing environment on the whole and also their intricate relations with each other. This will help him to decipher the trends of change with time.
In the developing countries and also in the developed countries to some extent, population pressure consistently necessitates gradual advances over the virgin lands within and outside the perimeters of the existing towns and cities.
These lands are to be used for providing additional housing colonies, community buildings, commercial centers, water supply projects, link roads, metros, industrial centers and so on. Whether a particular site is suitable for an identified project from engineering point of view is the job of a civil engineer to decide which he would do in consultation with an engineering geologist.
But firstly and primarily it is the town planner equipped with the geological knowledge who must take the decision regarding allocation of lands for different requirements keeping in mind that every meter of land that is taken out from the natural system for any construction activity is going to affect the system as a whole. The construction area so developed must not introduce a major element of disequilibrium in the natural set up. As far as possible, it should add to the harmony of the landscape.
The Regional Town Planner is responsible for adopting an integrated approach in all such cases of allocation of land for developmental projects. Geological knowledge will come to his help in this effort in a number of ways. Thus, a change inducted in the natural set up of an area due to a proposed new project is going to lead to a series of changes in the adjoining and even at distant places.
Some of these changes may prove harmful for the society he is supposed to serve. In nature, nothing works in isolation. As such all sound planning must be in tune with the natural features and processes of a region. A Railway Station for instance, if proposed and constructed in a belt lying between a forested area and a big town, may change the entire nature of the winds blowing over the town from the forest zone.
An industrial township, if located along the banks of a perennial river may provide easy and natural drainage for effluents from the industry but it may also cause incalculable harm to the flora and fauna and even human population located downstream. Forests and rivers are essentially geological entities; their processes are intimately related to the ground over which they exist.
Hence any disturbance with their systems may bring slow but sure changes that may be ultimately more harmful for the society when compared with benefits made available by them, such as from the railway station and the industrial estates.