Chapter 1

• Geology


  The study of the Earth, the materials of which it is made, the structure of those materials, and the processes acting upon them. It includes the study of organisms that have inhabited our planet.
• Geology

  • An important part is the study of how Earth's materials, structures, processes and organisms have changed over time
  • It is the most integrated of all of the sciences because it involves the understanding and application of all of the other sciences: physics, chemistry, biology, mathematics, astronomy, and others
  • It has an extra dimension, that of time—deep time—billions of years of it
• Geology


  A science that uses deductive reasoning and scientific methods to understand geological problems
• The Earth has a radius of about 6371 km, although it is about 22 km larger at equator than at poles
• Density, Temperature, and Pressure

  Increase with depth
• Layers of the Earth


  • Layers of different chemical composition
  • Layers of differing physical properties
• Layers of differing physical properties


  • Lithosphere (about 100 km thick)
  • Asthenosphere (about 250 km thick to depth of 350 km - solid rock, but soft and flows easily)
  • Mesosphere (about 2500 km thick, solid rock, but still capable of flowing)
  • Outer Core (2250 km thick, Fe and Ni, liquid)
  • Inner core (1230 km radius, Fe and Ni, solid)

  
• Bulk chemical composition of the Earth

  Mostly Iron (Fe, 34.6%), Oxygen (O2, 29.5%), Silicon (Si, 15.2%), and Magnesium (Mg, 12.7%), with other elements making up the other 8%
• The elements are distributed unevenly due to the layering, with Fe being concentrated in the core, Si, O2, and Mg being concentrated in the mantle, and Si, O2, and the other elements being concentrated in the thin veneer of the crust
• Why study Earth


  • To ensure Earth continues to be a great place to live
  • Earth is fascinating to study
  • To find and exploit resources sustainably
  • To understand the evolution of the environment and life
  • To minimize risks from natural hazards
  • To understand and address climate change
• Importance of geological studies for minimizing risks

  • Landslides blocking roads

  
• Mineral


  A naturally occurring combination of specific elements that are arranged in a particular repeating three-dimensional structure or lattice
• Approximately 98 Percent of the mass of the earth's crust is composed of eight chemical elements, with oxygen and silicon composing 75 Percent of it
• Primary minerals


  Original components of rocks that have not been altered chemically since their crystallization from molten lava
• Secondary minerals


  Result from the decomposition of a primary mineral or from the precipitation of the decomposition products of minerals
• Essential minerals


  • Feldspars, pyroxenes, micas
• Accessory minerals


  • Tourmaline, magnetite
• Minerals with their uses


  • Antimony, Asbestos, Barium, Bauxite, Beryllium, Chromite, Cobalt, Columbite-tantalite group, Copper, Feldspar, Fluorite, Gold, Gypsum, Halite, Iron Ore, Lead, Lithium, Manganese, Mica, Molybdenum, Nickel, Perlite, Platinum Group Metals, Phosphate, Potash, Pyrite, Quartz
• Perlite


  A lightweight substance with great water bearing characteristics, created from volcanic rock, the white stuff found in some potting soils
• Platinum Group Metals (PGM)


  Rare and therefore expensive, commonly used in jewelry but also benefit technology, largest source is from the byproduct of nickel mines
• Phosphate is necessary for all life on earth
• Potash


  The old fashioned term for Potassium, a major component in crop fertilizer, important in the human body for regulating pressure inside and outside cell walls, also used in soap manufacture
• Pyrite


  Commonly known as 'fool's gold', frequently seen in granite rocks where it adds sparkle, used by Native Americans as a mirror and occasionally in jewelry, its byproduct is used in ink and disinfectants
• Quartz (silica)


  The most abundant mineral on earth, the name for a large family of rocks including jaspers, agates, onyxes and flints, used in concrete, glass, scientific instruments, watches, and to make silicon semiconductors
• Rare Earth Elements


  • lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium ytterbium and lutetium, many used to create nuclear power
• Silica


  Used in desiccants to remove moisture from the air, also used in sandpaper and glass making
• Silver


  One of the precious metals, used as currency and in jewelry making, also used in medicine due to its anti-microbial properties
• Sodium Carbonate (soda ash or trona)


  Used to control the pH of products, used to make glass, paper, detergents and for softening
• Stibnite


  A major ore of antimony which is used in fireworks, rubber and glass making, mined principally in Romania
• Sulfur


  One of the only minerals to be found in its pure form in nature, a major ingredient in acid rain but also used in wine making and fruit preservation
• Tantalum


  Used when an alloy needs a high melting point and strength, used in missiles, aircraft parts and vacuums
• Titanium


  One of the most abundant and toughest metals on Earth, used extensively in human body repair
• Tungsten


  A metal that is stronger than steel and has a high melting temperature, used to make saw blades and in welding
• Uranium


  A highly radioactive element, used in cancer treatments, X-rays, military weapons and fuel for the space shuttle
• Vanadium


  Found in many foods and helps bones grow, useful in regulating blood sugar in diabetics and helps grow muscles for bodybuilders
• Zeolite


  Known as the 'stone that dances', used in wastewater cleanup and to reduce animal smells, can absorb ammonia
• Zinc


  Essential for a healthy life, deficiency can cause rashes, diarrhea, impaired taste and eye problems, used to treat macular degeneration, diabetes and the common cold
• Rocks are natural occurring solid cohesive aggregates of one or more mineral or mineral materials
• The three major rock types

  • Igneous rocks
  • Sedimentary rocks
  • Metamorphic rocks
• Sedimentary rocks make up 66% of the earth's crust, with 34% being igneous and metamorphic