GEOLOGY Lecture 1

• Geology


  The study of the Earth, its origin and history, the processes that shape it, and the resources that could be obtained from it
• Branches of Geology


  • Historical Geology
  • Physical Geology
  • Environmental Geology
  • Engineering Geology
  • Mining Geology, Petroleum Geology
  • Minerology, Petrology
  • Geomorphology
  • Geophysics, Geochemistry
• Historical Geology


  • The study of the Earth's history and evolution, involving understanding geological processes in the context of time, from the formation of the Earth to the development of its landscapes and life forms
• Branches of Historical Geology


  • Paleontology
  • Stratigraphy
  • Geochronology
• Paleontology


  The study of ancient life through the examination of fossils
• Stratigraphy


  The study of rock layers (strata) and layering (stratification)
• Geochronology


  The science of determining the age of rocks, fossils, and sediments
• Physical Geology


  • Focuses on the processes currently shaping the Earth's surface and interior, and the materials composing it
• Branches of Physical Geology


  • Volcanology
  • Seismology
• Volcanology


  The study of volcanoes and volcanic eruptions; their processes, dynamics, and characteristics
• Seismology


  The study of earthquakes and the movement of seismic waves through the earth, including sources and effects of earthquakes
• Environmental Geology


  • Applies geological science to address issues affecting the environment and human society, including studying natural hazards, managing natural resources, and understanding human impacts on the Earth
• Engineering Geology


  • Applies geological data, techniques, and principles to the study of rock and soil surfaces for the purpose of engineering design and construction
• Mining Geology


  • Involves the study of the Earth's resources (such as minerals, metals, and fossil fuels) from discovery through to exploitation, encompassing exploration techniques, resource estimation, and the sustainable extraction of minerals
• Petroleum Geology


  • A branch of geological sciences focusing on the exploration and extraction of oil and natural gas, integrating sedimentology, structural geology, and stratigraphy to understand the subsurface conditions favorable for oil and gas deposits
• Mineralogy


  The study of minerals, their composition, structure, properties, and the processes that lead to their formation
• Petrology


  The branch of geology that studies rocks and the conditions under which they form, covering igneous, metamorphic, and sedimentary rocks
• Geomorphology


  The study of landforms and the processes that shape the Earth's surface, investigating the formation and evolution of mountains, valleys, coastlines, and other landscape features
• Geophysics


  Applies the principles of physics to study the Earth's interior and its physical properties, using techniques like seismic wave analysis, magnetic and gravitational field studies
• Geochemistry


  Involves the study of the chemical composition of the Earth and its rocks and minerals, as well as the chemical processes and reactions that govern the composition of rocks and soils
• Engineering Geology


  • Deals with the application of geology for a safe, stable, and economic design and construction of civil engineering projects, applying geological knowledge in planning, designing and construction
• Geology in Construction Jobs


  • Planning
  • Design
  • Construction
• Topographic Maps


  Give details that are essential to understand relative merits and demerits of all the possible sites for the proposed structure, including the presence and nature of slopes, size, contours and depths of valleys and gorges, and rate of change of elevation
• Hydrological Maps


  Give details about the distribution and geometry of the surface water channels and the occurrence and depth contours of ground water below the surface
• Geological Maps


  Depict the petrological characters and structural disposition of rock types as developed in the proposed area, providing useful information regarding the fracturing and displacement that the site rocks might have undergone in the past
• Geological characters that have a direct or indirect bearing upon the design of a proposed project include: the existence of hard bed rocks and their depth from and inclination with the surface, the mechanical properties along and across the site, the presence and nature of structural weakness planes, the position of ground water table, and the seismic character of the area
• Construction - Geological knowledge is applied in the selection and proper use of the right type of materials of construction derived from the natural bedrocks, soils, banks and beaches
• Geology in Water Resources Development


  • Involves the exploration and development of water resources within areas, requiring an understanding of the water cycle in all essential details for effective planning and execution of major water resources development programs
• Geology in Town and Regional Planning


  • Aims to derive maximum benefits from the natural environment with minimum disturbance, applying geological knowledge for land utilization in the best and most aesthetic manner possible for developing cities and towns to meet social needs
• The Earth is commonly described as a spheroid, with an equatorial diameter of 12757.776 km, a polar diameter of 12713.824 km, a mean density of 5.517 g/cm^3, a volume of 1.083x10^27 cm^3, and a mass of 5.975x10^27 g
• Divisions of the Earth


  • Atmosphere
  • Lithosphere
  • Hydrosphere
  • Biosphere
• Layers of the Atmosphere


  • Troposphere
  • Stratosphere
  • Mesosphere
  • Thermosphere
• Troposphere


  The lowermost zone of the atmosphere rising from the surface of the earth and extending, on an average to a height of 11km, with its upper boundary called the tropopause
• Stratosphere


  The second layer of the atmosphere starting from the tropopause and extending up to an average height of 50km, where the temperature becomes constant for a height of 20km and then starts increasing
• Ozone Layer


  Starts at a height of 9km above the surface and continues up to 35km, with the maximum concentration of ozone at a height of 20-25km
• Mesosphere


  The third thermal zone of the atmosphere which begins at the stratopause at about 50km above the surface and continues up to a height of about 80km
• Thermosphere


  The fourth and last zone of the atmosphere, starting at about 80km and extending up to 500km and beyond
• Ionosphere


  A specialized zone that starts from 80km and extends upwards to variable heights, with the most strongly ionized layer located at the base and designated as the D-Layer
• Exosphere


  The region of the atmosphere beyond 700km, a low-density and high temperature region with a minimum of atomic collisions
• Lithosphere


  The stony part of the Earth, including the crust and a part of the mantle up to which the material exists in a definite solid state