Thursday, February 18th, 1999
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Lecture notes:
 
I. Great Smoky Mountain National Park (Smokies)

    A. Located in the Appalachian Mountains
            1.  The Appalachians range from Alabama up through Maine and the Atlantic Ocean; this is possible because the
                mountain range had been formed before the ocean was created

    B. Continental collision (the normal outcome of subduction)
            1. Continents passively move along with the ocean crust (ex. Australia, Japan)

            2. 50 millions years later (estimation)

                        a. This is like a pair of pants with a drawstring; the strings are the ocean crust while the bunches of cloth
                            from the pulling represent the continents; a modern example of this is India and Asia

                        b. Continental crust will deform on the surface because it is not as dense as the oceanic crust therefore
                            the continental crust cannot be subducted

    C. Biological diversity
            1. Plants are very diverse: azaleas, rhododendrons, mountain laurel, and wild flowers including wild orchids
 
            2. The abundance of rhododendrons represents how acidic the soil in the Smokies is (rhododendrons need acidic
                soil in order to grow)

            3. You find this biological diversity here because of the small storm systems throughout the Smokies

            4. There are many maple trees in the Smokies around the top of the mountains where basaltic soil is which maple
                trees thrive on

    D. Modern topography
            1. From State College south, the geography is totally unrelated to glaciation (no sculpting by glaciers) therefore
                shape is controlled by the rocks in the area

            2. Long, linear ridges from long continuous ridges
 
            3. Rock units in the valleys are made of shale (mud stone) or limestone (water soluble); rock units in the
                mountains are igneous, basalt, and very strong

            4. Because the valleys consist mostly of water soluble limestone, the valleys continue to get bigger due to erosion
                from rivers and streams flowing into the valleys

            5. The limestone valleys are prime for agriculture especially on the western margin of the Appalachians

            6. Limestone used to be coral originally (the Bahamas and Florida which consist of large amounts of coral will
                therefore become the limestone valleys of "tomorrow" or millions of years later)

            7. Some rocks have moved (advection) around 70 km (conservative #) according to the text, however, according
                to Professor Furman, it is around 200 km worth of movement which can be accomplished  because of the
                sliding along smooth rock

            8. Edge of the mountains is extremely steep
 
            9. Once you get higher into the bottom of the mountain, the soil becomes more basaltic and therefore not good for
                farming or agriculture

            10. Much of the repetition along the Smokies and Appalachians has to do with the folding along these areas

            11. Warm springs occur from Georgia up to the southern border of Pennsylvania (ex. White Sulfur Springs);
                    geologists use this as evidence to prove that this area is a point of subduction

II. Miscellaneous
    A. Obduction -- anything that gets caught in between the continents before they collide gets "stuck" above the
                            continent

    B. Blue Ridge
            1. Blue Ridge is about 4,500 feet

            2. It is a "chunk" of the Appalachian Mountains; the "chunks" consist primarily of granite that come from real
                deep below the surface (about 20 km deep)