Tuesday, April 20th, 1999

Announcements: Final examination is Tuesday, May 4th at 10:10 in 112 Kern Building.

Lecture notes:

Material for the final exam:

• Covers Chapters 20-26
• Topics to be covered in the final exam include:
      - Bryce Canyon
      - arches of Bryce Canyon
      - Great Basin
      - Grand Canyon
      - Isle Royale
      - Florissant
      - Dinosaur
• PLUS either chapter 28/ANWR or chapter 29/Cape Cod will be on the exam; Professor Furman is not sure which
  of the two topics will be covered on the exam; it will be announced in Tuesday, April 4th's lecture
• the review session will be held in class on April 29th

    B. Most rocks found in Bryce Canyon are cenosoic in age (approximately 40 million years old)

    C. The area here looks uninhabitable but that's not true because the area is mostly shale, sandstone, and limestone
    and therefore it is fertile soil

II. Arches
    A. It is a depositional and erosional environment

    B. Menosoic in age (approximately 80 million years old)

    C. The arches were mostly created by by wind erosion

    D. The arches are made of rounded rock sandstone

    E. Because salt is present it helps to form fractures in the rock therefore those fractures are susceptible to the wind
    erosion that forms them

III. Bristol Comb Pines
    A. Geologists can use the tree rings alone to find out age of area/rocks because the rock has to be nearly the same as
    the tree that sits on the rock

    B. Geologists can use the tree to take us back about 4,000 years then geologists can use the rings to take us back
    another 10,000 years; the lake sediments then take us back about 14,000 years; then geologists use the layers in ice
    cores which go back about 50,000; all of these are used to figure out the age of the land

IV. Grand Canyon
    A. Preserves about four (4) great events in history
            1. Most recent is a great uplift

            2. Couple 100 million years of rock were (majrity of 575 million years of rock layers) on or near ocean
            environments

            3. Basaltic/granitic

            4. Ancient pre-Cambrian rocks

    B. The Grand Canyon works in layers; it is most marine at the top and pre-Cambrian is at the bottom

    C. If you walk from the top of the Grand Canyon to the bottom you're walking through about one billion years of
    rock