What is Geology?

 

Geology is the study of the earth:

  • the materials that make up the earth
  • the structure of those materials
  • the processes that act upon those materials
  • the study of organisms that have inhabited our planet
  • and how everything have changed over time

 

Geology and Physical Geography

  • Geology: is the science that deals with the dynamics and physical history of the earth, the rocks of which it is composed, and the physical, chemical, and biological changes that the earth has undergone or is undergoing.

 

  • Physical Geography: the branch of geography concerned with spatial distribution of natural features and phenomena of the earth's surface such as
    • landforms,
    • drainage features,
    • climates,
    • soils, and
    • vegetation.

 

  • Human Geography: deals with the study of people and their communities, cultures, economies and interactions with the environment by studying their relations with and across space and place

 

 

Themes in Geology

  • Studying geology helps you understand the physical and natural sciences in general:
    • physics
    • chemistry
    • biology
    • physical geography

     

  • The earth has an internal structure. It consists of concentric layers:
    • core
    • mantle
    • crust

     

  • The outer layer of the Earth consists of moving plates:
    • lithosphere
    • plates
    • plate tectonics

     

  • Earth Systems Science: interaction of materials and processes:
    • land
    • oceans
    • air
    • life

     

  • The Earth is very old

 

  • Internal and external processes drive geologic phenomena
    • Internal processes:
      • heat from within the earth
      • plate movements
        • mountain building
        • earthquakes
        • volcanoes

         

    • External processes: driven by energy from within the Earth and from the sun:
      • movement of air and water
        • grinds and sculpts the Earth's surface
        • transports the debris to new locations, where it accumulates

         

  • Geologic phenomena affect society:
    • volcanoes
    • earthquakes
    • landslides
    • floods
    • groundwater
    • energy sources
    • mineral reserves

     

  • Physical aspects of the Earth Systems link to life processes. All life on the planet depends on such physical features as:
    • composition of soil
    • temperature
    • humidity
    • composition of the atmosphere
    • flow of surface and subsurface water

     

  • The Earth has changed dramatically over geologic time and continues to change

 

  • Most of the resources we use come from geologic materials:
    • fossil fuels: oil, natural gas, coal
    • metals
    • concrete
    • clay
    • fertilizer

 

The Scientific Method