SIR GEO

• Earth is approximately 4.54 Billion Years Old
• Systematic exploration and investigation of a new site

  1. Preliminary investigation

  2. Detailed geological survey of the site

  3. Applied geophysical surveys

  4. Boring, drilling and excavation

  5. Testing of soils and rocks
• Branches of Geology

  • Petrology - branch of geology that studies the origin, composition, distribution and structure of rocks.
• Branches of Geology

  • Mineralogy – is the study of minerals.
• Branches of Geology

  • Crystallography- study of crystals.
• Branches of Geology

  • Economic Geology – it deals with the study of minerals, rocks and materials of economic importance like coal and petroleum.
• Branches of Geology

  • Physical Geology – deals with the various processes of physical agent such as wind, water, glaciers and sea waves.
• Branches of Geology

  • Stratigraphy- is the study of stratified rocks and their correlation.
• Branches of Geology

  • Paleontology – is the study of fossils (the ancient remains of plants and animals).
• Branches of Geology

  • Structural Geology- the study of structures founds in rocks, it is also known as tectonic geology or simply tectonics.
• Branches of Geology

  • Historical Geology – the study of both stratigraphy and paleontology.
• Branches of Geology

  • Mining Geology – it deals with the study of application of geology to mining engineering in such a way that the selection of suitable sites for quarrying and mines can be determined.
• • Branches of Geology
  • Civil Engineering Geology – deals with all the geological problems that arise in the field civil engineering along with suitable treatments.
• Branches of Geology

  • Hydrology – deals with the studies of both quality and quantity of water that are present in the rocks in different states.
• Branches of Geology

  • Resources Engineering – the study of water, land, solar energy, minerals, forests, etc.
• Branches of Geology

  • Photogeology – deals with the study of aerial photographs.
• The crust makes up 1% of the Earth’s volume.
• The crust of the Earth is broken into many pieces called plates.
• The Crust

  • thinnest of all layers.
  • the Earth’s crust is made up of different types of rock; igneous, sedimentary, and metamorphic
  • The most abundant element in crust is oxygen by weight and by volume.
  • The rock crust is approximately called lithosphere
  • Discontinous body of water called hydrosphere
  • on land of masses of the lithosphere and hydrosphere, all living creatures exist, this described the biosphere
  • Enveloped by a layer of air which is called atmosphere
• The crust is only about 8 kilometers thick under the oceans(oceanic crust) and about 32 kilometers thick under the continents (continental crust).
• The Mantle

  • The mantle is the layer below the crust.
  • The mantle is the largest layer of the Earth (84% of the Earth’s volume)
  • The mantle is divided into two regions: the upper and lower sections.
  • The Mantle is the second layer of the Earth.
  • The temperature at the top of the upper mantle ranges from 500 to 900 degrees Celsius and it increases with depth
• The Core

  • The core is believed to have two parts: a solid inner core, with a radius of 1,220 km, and then a liquid outer core that extends to a radius of 3,400 km.
  • The temperature of the outer core ranges from 4400 °Cin the outer core to 6100 °C near the inner core
• Outer Core

  • The core of the Earth is like a ball of very hot metals.
  • The core is liquid.
  • The core is made up of iron and nickel are very dense.
• Inner core - of the Earth has temperatures and pressures so great that the metals are squeezed together and are not able to move.
• Tectonic Plates

  • Earth’s crust is broken into about 19 pieces
  • These plates move on top of the asthenosphere
• Asthenosphere

  • This is the layer below the lithosphere. This layer is “plastic–like”.
  • It is somewhat solid/liquid.
  • You can say that it is malleable.
• Site Investigation - exploration or discovery of the ground conditions to enable engineers to make informed design decisions.
• Suitability - To assess the general suitability of a site and its environs for the proposed work.
• Design - To enable an adequate and economic design, including for temporary works.
• Construction - identify sources of suitable materials such as concrete aggregate and fill and to locate sites for disposal of waste.
• Effect of Changes - assess the impact of the works on adjacent properties and on the environment.
• PARAMETERS TO BE DETERMINED IN A SITE INVESTIGATION

  • Geological Structure
  • Lithology
  • Ground water conditions
  • Seismicity
• STAGES IN A SITE INVESTIGATION

  1. Desk Study
  2. Site Reconnaissance
  3. Preliminary Site Exploration
  4. Detailed Exploration
  5. Preparation of Soil Investigation Report
• Aerial Surveys - The entire area involving an engineering study is photographed using sophisticated cameras and controls from low-flying airplanes.
• Photogeology - Its scope is enlarged by mapping of vast areas of the globe through satellites.
• Hydrogeological Surveys - conducted partly on the surface with a view of recording drainage pattern of the area and discharge and other leakage points.
• SUB-SURFACE EXPLORATION

  • Direct Methods - Involve examination of rocks or materials of the underground b digging of drill holes, trial pits, adits, shafts, galleries and exploratory tunnels.
• SUB -SURFACE EXPLORATION

  • Indirect Methods - Used extensively and involve application of geophysical techniques for obtaining fairly accurate idea of subsurface geology. e.g. Ground Penetrating Radar (GPR), Electomagnetic (EM), and Seismic
• Alfred Wegener - 1912. Meteorologist and astronomer.
• Pangaea - one land mass