1. Energy in the Geosphere
Learning Goals:
Understand that there are 3 plate boundaries and that specific geological events occur at each boundary.
Understand that the movement of plates occurs as a result of energy in the core of the Earth. (Nuclear: Radioactive Decay)
Understand that changes in density result from temperature inputs.
Understand that changes in density create convection currents.

2. A little Review Basic Definitions The Formula Mass: Volume: Density:
the amount of matter in an object
Volume:
the amount of space an object occupies
Density:
the ratio between the mass of the object and the amount of space that the object occupies
The Formula
Density=mass/volume

3. Density Calculations Example #1 D=m/v
Calculate the density of a 23g rock with a volume of 3.2cm3.
D=m/v
D=23/3.2
D=7.19g/cm3

4. Density Calculations Example #2
The solid inner core of the Earth has a density of approximately 13g/cm3. Calculate the mass of 5cm3 of this substance.
D=m/v
13=m/5
13*5=m
65g=m

5. Transforming Boundary
Understand that there are 3 plate boundaries and that specific geological events occur at each boundary.
Transforming Boundary
Definition:
Two plates sliding next to each other in opposite directions.
Geologic Feature
Strike-Slip Fault Line
Diverging Boundary
Two plates moving away from each other.
Oceanic Ridge/Location where “new” surface rock appears
Converging Boundary
Two plates sliding toward each other.
Oceanic Trench/Mountain Building/Volcanic Activity

6. The Composition of the Earth
Understand that the movement of plates occurs as a result of energy in the core of the Earth. (Nuclear: Radioactive Decay)
The Composition of the Earth

7. Lower Mantle: Liquid; convection currents
Understand that the movement of plates occurs as a result of energy in the core of the Earth. (Nuclear: Radioactive Decay)
The Inner Core: Solid Iron; b/c as radioactive elements decay they keep releasing energy until they become stable.
The Outer Core: Liquid Iron; b/c as radioactive elements decay they release energy (Thermal)
Lower Mantle: Liquid; convection currents
Upper Mantle: (Asthenosphere) Solid-ish; as the distance from the core increases, materials begin to solidify.
Crust (Lithosphere) Solid; this is where the plates are located

8. Understand that changes in density result from energy inputs.
An increase in temperature is an energy input or energy transfer!
As temperature ↑, volume ↑;
As temperature ↑, mass↔;
As temperature ↑, density ↓.
As the density of an object ↓,
the object will go ↑.

9. Understand that changes in density create convection currents.
The material moves away from the heat source and cools.
The cooled material becomes more dense and falls.
The heated material becomes less dense and rises.
Material near the core is heated by radioactive decay.