Plate Tectonics and Mountain Building GPH 111

Plate Tectonics and Mountain Building Game plan: Intro to Plate Tectonics, Wegner, and Pangea Major Plate Boundaries Terrain Accretion and Continental Shields Plate Tectonics and Mountains Stress and Strain – Folding and Faulting

Continental Movements: Pangea to Now… Super-Continent Cycles

Continental Movements Australia - the fastest moving continent, 6.5 cm / year

Major Plate Boundaries… Convergent Divergent Transform Hot Spots – not technically a boundary, but cool and interesting none the less

Convergent Plate Boundary Continent – Continent, Continent – Ocean, and Ocean - Ocean

Convergent Plate Boundary Continent – Continent, Continent – Ocean, and Ocean - Ocean

Convergent Plate Boundary Continent – Continent, Continent – Ocean, and Ocean - Ocean Mariana Trench - 35,802 feet deep at the deepest, this is where plates dive into the mantle. That is 8 tons per square inch…

Divergent Plate Boundary Mid-Ocean Ridges

Divergent Plate Boundary Mid-Ocean Ridges Generates new ocean sea floor over time - driven by convective currents.

Divergent Plate Boundary Mid-Atlantic Ridge

Oldest ocean floor ~180 million years Divergent Plate Boundary Oldest ocean floor ~180 million years

Transform Boundaries San Andreas Fault

Hot Spots Think: Balloon on a string… Hawaii

Hot Spots Columbia Plateau and Yellowstone

Plate Tectonics and Mountain Building: Terrain Accretion and Continental Shields Plate Tectonics and Mountains - Convergent Boundaries - Fault Block Mountains - Isostatic Mountains

Continental Shields Older nucleuses that younger crust (objects like Japan) adheres to are called continental shields and the process is called terrain accretion

Plate Convergence Mountains

Isostatic Mountains - Superstitions Continents behave like wooden blocks in water… Mountains Uplift as they are eroded… Basins depress as they fill…

Isostatic Mountains Old volcanic center erupted 18 million years ago, and collapsed on itself, and then rebounded into the current mountain range Superstition Mountains http://atlas.geo.cornell.edu/education/instructor/topography/isostasy.html

Fault Block Mountains Nevada, US

Plate Tectonics and Mountain Building: Stress and Strain Faulting - Normal Fault - Reverse Fault - Strike Slip Fault

Stress and Strain My Snickers Tension Compression Shear Stress - force on the rock; Strain - the resulting response

Types of Faults Your Snickers

a. Slide #1 c. b.

a. Slide #2 c. b.

a. Slide #3 c. b.

a. Slide #4 c. b.

Things to Know: Alfred Wegner and his early proposal of Continental Drift, but known today as plate tectonics The energy source that drives plate tectonics The name for the most recent super continent, Pangea The major plate boundaries: convergent, divergent, and transform, and also hot spots Continental shields and terrain accretion Three ways to generate mountains: convergent plate boundaries, Isostatic, and Fault Block The difference between stress and strain Under what circumstances will a rock behave in a ductile or brittle fashion The major fault types: normal, reverse, and strike slip (be able to diagram them) Help: Chapter TL