1. Day 3: Rheology and Heat Flow
Earth Model
Day 3: Rheology and Heat Flow
Powerpoint for day 3 of Earth Model activity. 7 slides in total.
Image source:

2. What is Rheology, Viscosity?
Rheology: The study of the deformation and flow of matter.
Viscosity: The extent to which a fluid resists a tendency to flow.
How do these concepts apply to the layers of the Earth?
Describe Rheology and Viscosity. Ask students how the concepts could be used to describe layers in the Earth and other material such as water, ketchup….etc.

3. Follow-up to previous slide.

4. Mention the differences between Mechanical and Chemical layers in the Earth.
Introduce terms:
Deformation: Alteration of shape, as by pressure or stress.
Brittle: Likely to break, snap, or crack, as when subjected to pressure.
Ductile: Easily molded or shaped.
Talk about how Lithosphere is made up of stronger (brittle) rock layer, whereas the Athenosphere below is made up of a weaker (ductile) layer.

5. Heat Flow Distinct types of Heat Transfer in the Earth:
Convection: Transfer of heat within a liquid or gas.
Conduction: Transfer of heat through matter by direct contact.
Thermal Radiation: The energy radiated by solids, liquids, and gases in the form of electromagnetic waves as a result of their temperature.
Distinct types of Heat Transfer in the Earth:
Convection: Transfer of heat within a liquid or gas.
Conduction: Transfer of heat through matter by direct contact.
Thermal Radiation: The energy radiated by solids, liquids, and gases in the form of electromagnetic waves as a result of their temperature.

6. Describe conduction, convection, and radiation by discussing what happens when you boil a pot of water.
Put hands near heat source = thermal radiation
Hot handle = conduction
Moving water = convection
Image of earth shows convection within the mantle. Hot material rises as plumes and colder material sinks within the mantle. The main form of heat transfer through the brittle lithosphere is conduction.

7. Earth’s inner and outer core
Inner core is solid. Heat transfer through the core to the outer core can be described as conduction.
The outer core is liquid and its movements are complex. The outer core is rich in Fe (iron) and hosts a process through which a rotating, convecting, and electrically conducting fluid can maintain a magnetic field over astronomical time.
This layer is responsible for the Earth’s magnetic field, which protects us from the Sun’s deadly solar wind.