FAULTS “Little” Cracks in the Earth’s Crust

FAULTS VS. PLATE BOUNDARIES Faults are cracks in the Earth’s Crust where the rock on either side is moving in different directions. Faults can be large or small but they DO NOT have to be at the edges of the plates. Plate Boundaries occur at the edges of the very large tectonic plates. Most of the earthquakes occur at Plate Boundaries.

RECENTLY DISCOVERED FAULTS Scientists are still discovering new faults. Many of these new discoveries are made my UW Geology professors and students.

THE SEATTLE FAULT ZONE DISCOVERED IN This is a good but scary article on the Seattle Fault.

LET’S THINK IT THROUGH: If you live near a fault are earthquakes your friend?

THE BIG IDEAS FOR THE FAULT LAB (INQUIRY 15.3) As the crust moves rock along the fault line catches due to “friction” (stick). As the crust continues to move pressure builds up in the areas of stick. When the fault finally ruptures (slip) energy is released in the form of an earthquake. The greater the stick force, the greater the slip will be and the more energy released via the earthquake. More smaller earthquakes mean that the pressure never really builds up much (small stick = small slip). When the rock around the faults stops moving scientists worry lots of pressure is building up and may result in a very large quake.

MATERIALS LIST Goggles 2 wooden blocks with Velcro 1 string 1 spring scale 1 roll of masking tape 1 bolt 2 washers 1 wing nut