Introduction to Geology

• As Earths forms layers the siderophile elements loose GPE transferred into thermal energy enough to melt it -> molten outer core
• Change of state from outer to inner core releases heat to the surroundings
• Inner core grows ~0.5mm per year meaning it still produces heat
• Lithosphere doesn’t conduct heat so it’s trapped in the mantle
• Geological timescale - 4600 million years ago (MYA)
• Geotherm


  A line that shows the temperature variation with depth
• Geothermal Gradient = change in temp/ change in depth
• Thermal Flux


  The rate of heat transfer through a surface per unit Time
• Frictional Heating


  Heat transfers from a higher temp surface to another cooler material