Introduction to Earth Science

• Earth Science

  Investigation of interactions among the four components of the Earth systems—the atmosphere, hydrosphere, biosphere, and geosphere
• Main Branches of Earth Science

  • Geology
  • Meteorology
  • Oceanography
  • Astronomy
• Geology

  Field of study concerned with the solid Earth—the materials of which it is made, the structure of those materials, and the processes which acts upon them
• Branches of Geology

  • Physical Geology - examines Earth's composition and the processes occurring on and beneath its surface.

  
  

  • Historical Geology - examines the origin of the Earth and changes in life through time.
• Oceanography


  Study of the composition and movements of seawater, as well as costal processes, seafloor topography, and marine life
• Meteorology


  Encompasses the study of the atmosphere and the processes that result to weather and climate
• Astronomy

  Scientific study of celestial objects and phenomena that originate outside the Earth's atmosphere
• Catastrophism


  The Earth has been affected in the past by sudden, short-lived, violent events, possibly worldwide in scope
• Uniformitarianism


  "The present is the key to the past" - Earth's landscapes like mountains and oceans formed over long period of time through gradual processes
• Law of Conservation of Energy: Energy can not be created nor destroyed
• Kinetic Energy

  The energy possessed by objects in motion
• Gravitational Potential Energy

  Stored energy as a result of the gravitational attraction of the Earth
• Heat

  Form of energy caused by the motion of the atoms; the sum of kinetic energy of each atom in a sample
• Temperature

  The measure of average speed of atoms in a sample
• Types of Heat Energy

  • Internal Heat Energy
  • External Heat Energy
• Internal Heat Energy

  Stems from Earth's core and the remaining heat when Earth first formed; includes Geothermal Energy and Long Wave Radiation
• External Heat Energy

  Heat that comes from the sun; drives weather and climate; includes Short Wave Radiation
• Shortwave Radiation has more energy than Longwave Radiation
• Heat Transfer Mechanisms

  • Conduction
  • Convection
  • Radiation
• Big Bang


  The whole universe expanded from a hot dense state, singularity, into the vast cosmos it is today; proposed by Georges Lemaitre in the 1920's
• Supporting Evidence for Big Bang Theory

  • Expansion of the universe (Redshift)
  • Abundance of light materials (H & He)
  • Cosmic microwave background radiation (Cosmic Glow)
• Redshift

  Wavelength of the light is stretched, so the light is seen as 'shifted' towards the red part of the spectrum
• Cosmic microwave background radiation (Cosmic Glow)

  Visible & Ultraviolet rays converted to Microwave
• Theories on the Formation of the Solar System

  • Nebular Hypothesis
  • Planetesimal Theory
  • Protoplanet Hypothesis
• Protoplanet Hypothesis

  At terrestrial planets, there were higher temperatures; Jovian planets were formed at distances due to low temperatures
• Models of Solar System Formation

  • Catastrophic
  • Gradual Accretion
  • Protoplanet Formation
  • Near-collision of stars
• Earth's Shape

  Oblate spheroid
• Earth's Age

  4.54 billion years
• Earth's Composition

  Fe, O, Si, Mg, S, Ni, Ca, Al, trace elements
• Earth's Equatorial Radius

  6378 km
• Earth's Density

  5.52 g/cm3
• It would take 38 minutes and 11 seconds to fall through the Earth
• Layers of the Earth

  • Crust
  • Mantle
  • Core
• Crust

  Based on chemical composition; Oceanic - older, colder, denser, thinner; Continental - younger, hotter, less dense, thicker
• Mantle

  Based on chemical composition; biggest layer of the Earth by volume; made of hot ultramafic rocks called peridotite
• Core

  Based on chemical composition; predominantly iron and nickel, and makes up about 31% of the Earth; Outer - liquid; Inner - solid
• Layers of the Earth

  • Lithosphere
  • Asthenosphere
• Lithosphere

  Made of the crust and the rigid top portion of the upper mantle
• Asthenosphere

  The ductile portion of the Earth which can freely flow due to high temperatures
• Isostasy

  The ideal theoretical balance of all large portions of Earth's lithosphere as they float on the denser underlying layer, controlling regional elevations