The Rock Cycle

• What is the lithosphere made up of?


  crust and upper mantle

  includes rocks, minerals and solids that provide environmental resources and services important to human societies
• Mineral resources extracted from lithosphere


  - iron = buildings

  - aluminium = packaging foil

  - tin = solder, rust prevention

  - uranium= nuclear fuel for power stations
• Industrial minerals and construction materials


  Limestone: cement and building blocks

  Gypsum (china clay): plaster and food additive

  Sulfur: pest control

  Salt: food additive and road de-icing
• Geological processes that created exploitable mineral deposits


  Igneous Processes

  -> hydrothermal deposition

  Metamorphic Processes

  Sedimentary Processes

  ->Proterozoic marine sediments

  ->alluvial deposits

  ->evaporites

  ->secondary enrichment

  ->biological sediments
• Unsustainable exploitation of resources can result in...


  ->exhaustion of reserves

  ->production of harmful wastes

  ->land degradation

  ->lower quality of life for now and future
• fractional crystallization


  The process by which the crystals formed in a cooling magma are segregated from the remaining liquid at progressively lower temperatures.
• Hydrothermal deposition


  Igneous intrusions heat surrounding minerals creating a mineral rich solutions. This travels away and cools, crystallising separating from the solution in order of solubility
• example of hydrothermal deposition metals


  Tin, copper, lead, silver, gold and arsenic
• Metamorphic Processes


  alter existing rocks with high temperatures and pressure

  E.g limestone to marble
• sedimentary processes


  cause minerals to settle and build to produce layers of deposited sediment. deposition and subsequent cementation at earths surface create sedimentary rocks and minerals
• Proterozoic marine sediments


  These include the iron oxide deposits produced by the reaction of dissolved iron minerals with the oxygen produced by photosynthesis. This occurred in the early Proterozoic era and delayed the build-up of oxygen in the atmosphere.
• alluvial deposits


  Minerals that were carried and separated by flowing water e.g gold, diamond, tin ore and gravel
• Evaporites


  sedimentary rocks formed from minerals left after water evaporates
• Secondary enrichment


  many economically important metals can form minerals that are soluble or insoluble depending on the conditions, especially the availability of oxygen
• Biological sediments


  Living organisms form mineral deposits- often concentrate minerals that can be deposited in sedimentary rocks
• Example of biological sediments


  Shells of marine organisms- limestone and chalk

  Terrestrial vegetation- coal

  Marine organisms- crude oil and natural gas