Rock type and structure affecting weathering

Cards (24)

  • How does rock type influence weathering?
    It affects rate and type of weathering
  • What are the factors due to which rock type influences weathering?
    Chemical composition, cements, joints
  • What is limestone primarily composed of?
    Calcium carbonate
  • Why is limestone susceptible to carbonation solution?
    Because it consists of calcium carbonate
  • What are iron oxide-based rocks prone to?
    Oxidation
  • How resistant are quartz cements to weathering?
    Very resistant
  • What is the relationship between rock structure and weathering?
    • Joint patterns control water movement
    • Create lines of weakness
    • Coarse-grained rocks weather quickly
    • Fine-grained rocks have greater surface area
  • What is the porosity percentage of granite?
    1%
  • What is the permeability of sandstone?
    500
  • What is the porosity percentage of clay?
    45%
  • How do coarse-grained rocks weather compared to fine-grained rocks?
    Coarse-grained rocks weather quickly
  • Who stressed the importance of individual minerals in weathering?
    Goldich in 1939
  • What type of materials resist weathering according to Goldich?
    Resistant materials like quartz
  • How do limestone and granite illustrate the interrelationship of geology and climate on landforms?
    • Limestone reacts with acidified water
    • Granite has a granular texture
    • Limestone is rich in fossil content
    • Granite is rich in quartz
  • What happens to non-porous limestones when heated to 1000 degrees?
    They dissociate calcium carbonate, CO2, and limestone
  • What type of rock is granite?
    Igneous
  • How do limestones differ from granites in terms of fossil content?
    Limestones are rich in fossil content
  • What is the permeability of limestone?
    30
  • What is the permeability of clay?
    10
  • What is the significance of joint patterns in rocks?
    They create lines of weakness for weathering
  • How does the chemical weathering of limestone differ from granite?
    Limestone reacts with acidified water, granite does not
  • What is the effect of high permeability in coarse-grained rocks?
    They weather quickly due to large voids
  • What is the chemical composition of limestone?
    Calcium carbonate
  • What is the role of surface area in fine-grained rocks regarding weathering?
    They offer greater surface area for weathering