1. Light refreshments beforehand!

2. Plate Tectonics - Part II (What ELSE can happen??)

3. I. The Appalachian Mountains are a product of ancient subduction followed by collisions.

4. The giant folds in the rocks that are so visible in the satellite images are also readily available from the window of a plane.

5. Other bits and pieces of land - islands and the like - can also get caught up in the convergent plate process. This is what creates what are now recognized as accreted terranes, (originally called " suspect terranes ").

6. IMAGINE... what the geologic situation would ultimately look like if Australia were to be moving to the NW, pushing everything from New Guinea to Sumatra into the SE margin of the Asian mainland...

7. What might the future hold???

10. MAYBE!!!!! The BASIN AND RANGE Province of the western U.S., including all of Nevada and parts of surrounding states, MAY be an area where North America is trying to split apart!

11. The mantle upwelling beneath the East Pacific Rise doesn't just cease to exist in between the Gulf of California and the Gorda Ridge!

12. This region has been broadly UPLIFTED by tectonic forces pushing up from beneath. The plains of Wyoming are very flat, but 7000-8000 feet (2100 to 2400 m) above sea level. The Grand Canyon catches the eye for its tremendous depth, but the North Rim is also over 8000 feet (2400 m) above sea level! Note how FLAT the upland surface is!

13. In most other areas, the rocks have fractured in normal faults, which are produced only by stretching a brittle material - pulling it apart. On a larger scale, this then shows up in repeated patterns of block faulting

14. The Humboldt Range of Nevada, for example, is part of this system. This produces a series of downdropped blocks called GRABENS in between the uplifted HORSTS. (The grabens are the valleys, the mountain ranges the horsts.)

16. What COULD happen as an alternative scenario, as a result of this process in the western U.S.?

21. It's thinking about scenarios like this that has led some geologists to call geophysics "The realm of conjecture, speculation and dreams."

22. ComingTuesday: Producing Islands by Rifting