Geology in National Parks
• Topics to ponder…….
• Is building a cell tower that overlooks Old Faithful a good idea?
What is Geology (Geosciences)?
• The study of - all aspects of the physical environment
– the Earth
The Earth System
• What is a system?
• Solid Earth
• Hydrosphere
• Atmosphere
• Biosphere
The Earth System
• Do the parts of the system interact?
Question
• Discuss the following question with the people next to you…
• Is the configuration of the oceans and continents merely a coincidence?
Why or Why not?
The Solid Earth
• Internal Processes = the result of Earth Structure - Core-mantle system
• The Layered Earth - Parts -
1. Crust
2. Mantle
3. Core
• Outer Core = Internal Heat Engine
• Heat Source??
– natural radioactive materials
The Solid Earth
• Core-mantle system
• Mantle Convection
• Heating mantle from below causes convection……
• Convection in mantle causes crust to move and break into plates
• Plate Tectonics System
Plate Tectonics System
• Parts = Outer mantle and crust
• Plates = Lithosphere
– Rigid and brittle
• Plates float on Asthenosphere
– Partially liquid
• Movement because of convection
Plate Tectonics System
• Lithosphere = two types of crust - ocean and continental
• Ocean crust = thin and dense
• Continental crust = thick but less dense
• Plates of lithosphere move in different directions
• Interact at Plate Boundaries
Plate Tectonics System
• Plate Boundaries = the most dynamic spots on earth
• 2 major types
• Divergent - new ocean crust created - volcanic eruptions
• Convergent - ocean crust destroyed - large volcanoes and mountains
• 8 major plates
• Continents change position over time as ocean basins open up and close
down…
Plate Tectonics System
• Earth materials and plate boundaries
• Divergent - new rocks are created
• Convergent
– Old rocks destroyed -> creating new rocks
– Old rocks are compressed, buried, and heated
Processes at the Surface of Earth
• The Hydrologic Cycle
– Solar powered cycle that redistributes water on earth
• Reservoirs
– Oceans
– Atmosphere
– Land (streams, lakes, groundwater)
– Glacial ice
• Processes
– Evaporation
– Condensation
– Precipitation
– Infiltration & run off
– Freezing and melting
Processes at the Surface of Earth
• Earth materials and surface processes
• Old rocks break down - weathering
• Weathering produces particles and solutions
• Processes
• Weathering - erosion - transport - deposition - burial
The Rock Cycle
• Interaction of Earth Process (Internal and Surface processes)
• Rocks continually
– Created and destroyed
– Transformed
– Recycled
• Igneous Rocks
• Sedimentary Rocks
• Metamorphic Rocks