earth sci

• Habitability Factors

  For the planet to be habitable, it should be at the right distance from its star (Goldilocks Zone), have liquid water, and have the right atmospheric composition
• Earth is 149.6 million km or 1 Astronomical Unit from its star
• Liquid Water


  Life needs water and it is essential in maintaining the biogeochemical processes. It covers 71% of Earth's surface
• Atmospheric Composition


  Earth's atmosphere is 78% Nitrogen, 21% Oxygen, 1% Argon and other gases
• Magnetic Field


  The magnetic field shields surface life from dangerous charged particles and is generated in the planet's molten outer core
• Geologic Processes

  Plate tectonics, volcanic activity, mountain building, and erosion maintain a suitable atmosphere and create diverse landscapes
• Earth's Geosystem


  A complex concept representing an area of Earth where various subsystems interact and influence each other
• System

  A set of interconnected components that are interacting to form a unified whole
• Open System


  Freely exchanges both matter and energy with its surroundings
• Closed System


  Allows the exchange of energy with its surroundings but not matter
• Earth as a planet is a closed system, but within Earth is an open system
• Hydrosphere


  Refers to surface water on Earth, along with groundwater
• Distribution of Water

  • Freshwater - 2.56%
  • Saline water - 97.44%
  • Ground water - 0.77%
  • Glaciers - 1.76%
  • Oceans - 96.5%
  • Saline groundwater and lakes - 0.94%
• Atmosphere


  The layers of gases that envelop a planet, held in place by the planet's gravity
• Layers of the Atmosphere

  • Troposphere
  • Stratosphere
  • Mesosphere
  • Thermosphere
  • Exosphere
• Geosphere


  The layer of Earth that includes the rocks, minerals and landforms of the surface and interior
• Layers of the Geosphere

  • Crust
  • Mantle
  • Core
• Biosphere


  The region of the planet that encompasses all living things - animals, plants, and single-celled organisms
• Biogeochemical Processes


  Processes that interconnect the Earth's subsystems, such as the water cycle, rock cycle, and carbon-oxygen cycle
• Photosynthesis


  The process where plants absorb sunlight and produce glucose and oxygen
• Cellular Respiration


  The process of using glucose and oxygen to make energy (ATP)
• Nitrogen Cycle


  Transforms the inert nitrogen in the atmosphere into a more usable form for living organisms
• Mineral


  Any naturally occurring inorganic solid that possesses an orderly crystalline structure and can be represented by a chemical formula
• Mineral Properties


  • Luster
  • Color
  • Streak
  • Cleavage
  • Fracture
  • Density
  • Specific Gravity
  • Effervescence
• Luster


  The appearance or quality of light reflected from the surface of a mineral
• Types of Luster

  • Metallic
  • Nonmetallic (dull, vitreous, silky, greasy, adamantine, earthy, resinous)
• Color


  The quality of a mineral with respect to the absorption or refraction of light of particular wavelengths
• Streak


  The color of the powder produced when a mineral specimen is drawn across a surface such as unglazed porcelain
• Types of Cleavage

  • Basal
  • Prismatic
  • Cubic
  • Rhombohedral
  • Octahedral
• Types of Fracture

  • Conchoidal
  • Hackly
  • Uneven
• Density


  The mass per unit volume of a mineral, expressed in grams per cubic centimeter
• Specific Gravity


  The ratio of a mineral's weight to the weight of an equal volume of water
• Effervescence


  The fizzing or bubbling that takes place when a dilute solution of hydrochloric acid (HCl) is applied to a mineral
• Mineral Groups


  • Native Elements
  • Oxides
  • Halides
  • Arsenates, Phosphates, Vanadates
  • Silicates
  • Organic Minerals
  • Borates and Nitrates
  • Sulfates, Chromates, Tungstates, and Molybdates
• Igneous Rock


  Rock formed by the crystallization of magma or lava, classified based on location of formation, composition, and texture
• Igneous Rock Types

  • Intrusive (Plutonic)
  • Extrusive (Volcanic)
• Igneous Rock Texture

  The overall appearance of an igneous rock based on the size, shape, and arrangement of its mineral grains
• Igneous Rock Texture Types

  • Glassy
  • Porphyritic
  • Phaneritic
  • Aphanitic
  • Pyroclastic
  • Vesicular
  • Pegmatitic
• Felsic


  Light-colored igneous rocks with >65% silica and <15% dark minerals
• Mafic


  Dark-colored igneous rocks with 45-53% silica and 46-85% dark minerals