Note for Engineering Geology - EG by rupendra duggirala

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Lecture Notes on ENGINEERING GEOLOGY III B.Tech (Civil Engineering) I Semester By Mr. RUPENDRA DUGGIRALA Assistant Professor Department of Civil Engineering Marri Laxman Reddy Institute of Technology and Management

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www.mlritm.ac.in Notes on Engineering Geology for B.tech (civil ) – III year students UNIT: 1 PHYSICAL GEOLOGY INTRODUCTION GEOLOGY (in Greek, Geo means Earth, Logos means Science) is a branch of science dealing with the study of the Earth. It is also known as earth science. The study of the earth as a whole, its origin, structure, composition and the nature of the processes which have given rise to its present position is called as geology. Geology comprises the following branches: 1. Crystallography 2. Mineralogy 3. Petrology 4. Geophysics 5. Geochemistry 6. Structural Geology 7. Stratigraphy 8. Physical Geology 9. Geomorphology 10. Paleontology 11. Hydrogeology 12. Engineering Geology 13. Photo Geology 14. Economic Geology 15. Mining Geology Crystallography: The study of the characters of crystals is known as crystallography. Crystals are bodies bounded by flat faces ( surfaces), arranged on a definite plane due to internal arrangements of atoms. Mineralogy: The study of the characters of minerals ( eg: quartz, pyroxene, amphibole, mica, chlorite, garnet) is known as Mineralogy. A mineral is a naturally occurring homogeneous substance, inorganically formed with a definite chemical composition, with a certain physical properties and crystalline structures. Note: Coal, oil etc are considered as minerals THOUGH they arises by organic matter under exceptional conditions . Petrology: The study of rocks in all their aspects including their mineralogies, textures, structures (systematic description of rocks in hand specimen and thin sections); origin and their relationships to other rocks. Geophysics: The section of the earth which include the structure, physical conditions and evolutionary history of the earth as a whole. Rupendra Duggirala, Assistant professor, MLRITM

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www.mlritm.ac.in Geochemistry: The study of chemical composition of minerals and rocks of the earth. Structural Geology is the study of rock structures such as folds that have resulted from movements and deformation of the earth’s crust. Stratigraphy: The study of the stratified rocks especially their sequence in time, character of the rocks and correlation of beds at different localities. the Physical Geology: It deals with the geological processes which bring about changes in the crust and upon the surface of the earth. It also deals with the surface features of the earth ( land forms ) or its topography Geomorphology: The description and interpretation of land forms. Palaeontology is the study of ancient life, determination of environment, evolution of organisms etc.. Hydrogeology-- the study of the geological factors relating to earth’s water. Mining Geology deals with the method of mining of rocks and mineral deposits on earth’s surface and subsurface. ENGINEERING GEOLOGY: the principles and methods of geology is adopted for the purpose of civil engineering operations. Broadly speaking, engg geology has two divisions: (1) The study of raw materials (2) The study of the geological characteristics of the area where engineering operations are to be carried out such as Groundwater characteristics; the load bearing capacity of rocks; the stability of slopes; excavation; rock mechanics etc for civil engineer. SCOPE OF GEOLOGY: In Civil Engineering  Geology provides necessary information about the construction materials at the site used in the construction of buildings, dams, tunnels, tanks, reservoirs, highways and bridges.  Geological information is most important in planning stage, design phase and construction phase of an engineering project.  Geology is useful to know the method of mining of rock and mineral deposits on earth’s surface and subsurface.  Geology is useful for supply, storage and filling up of reservoirs with water. IMPORTANCE OF GEOLOGY FROM CIVIL ENGINEERING POINT OF VIEW  Before constructing roads, bridges, tunnels, tanks, reservoirs and buildings, selection of site is important from the point of stability of foundation.  Geology provides a systematic knowledge of construction materials and their properties. Rupendra Duggirala, Assistant professor, MLRITM

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www.mlritm.ac.in  The knowledge about the nature of the rocks in tunneling and construction of roads.  The foundation problems of dams, bridges and buildings are directly related with geology of the area where they are to be built.  The knowledge of ground water is necessary in connection with excavation works, water supply, irrigation and many other purposes.  The knowledge of Erosion, Transportation and Deposition (ETD) by surface water helps in soil conservation, river control.  Geological maps and sections help considerably in planning many engineering projects.  If the geological features like faults, joints, beds, folds are found, they have to be suitably treated. Hence, the stability of the rock structures is important.  Pre-geological survey of the area concerned reduces the cost of planning work. Minerals, Rocks and soils constitute earth materials. evaluation and operations in civil engineering practice. They play a vital role in the site Whether it is tunneling, hydro-electric projects, ground water development, foundation for structures, study of slope stability etc.. a basic understanding of the earth materials is essential. Thus, study of minerals, rocks and soils forms the first step in civil engg point of view. Hence, a civil engineer should know the introduction of Geology and its branches and importance of a few branches such as Physical Geology, Petrology; Structural Geology and so on …… IMPORTANCE OF GEOLOGY PHYSICAL GEOLOGY, PETROLOGY & STRUCTURAL IMPORTANCE OF PHYSICAL GEOLOGY: It deals with the geological processes which bring about changes in the crust and upon the surface of the earth. It also deals with the surface features of the earth ( land forms ) or its topography. The earth is Rupendra Duggirala, Assistant professor, MLRITM