Part I. Short Answer use a few sentences to answer each question. Be sure to use verbs and nouns in every sentence. (5 pts. each)

1. Why is a volcano fed by very viscous magma likely to be a greater threat than a volcano supplied with very fluid magma?

2. In what ways are granite and rhyolite different? In what ways are they similar?

3. Minerals, by definition, must be "crystalline." What does "crystalline" mean?

4. Why is shale the most abundant sedimentary rock we see at the Earth's surface? In what sorts of geological environments is shale deposited? (i.e., Where does it form?)

5. Why are there so few craters on the surface of the Earth (compared, for example, with the Moon)?


Part II. Multiple Choice. Circle the letter of the best answer to each question. (3 pts. each)

1. What products would you expect to result from the complete chemical weathering of a granite?
a. clay, dissolved ions, and residual quartz
b. calcite, dissolved ions, and sometimes magnetite
c. caliche, dissolved ions, and residual olivine
d. clay, olivine, and caliche
e. clay, micas, and feldspars

2. The oceanic ridge system is a place where
a. crustal plates diverge
b. crustal plates merge and subduct
c. crustal plates slide past each other along transform faults
d. "hot spots" feed magma to volcanoes
e. any of the above could be correct depending on the ocean ridge you are talking about

3. All silicate mineral have what in common?
a. they all form from magmas
b. they all contain silicon-oxygen tetrahedra
c. they all contain iron and magnesium
d. they all contain silicic acid
e. they all break down quickly at the Earth's surface

4. Which of the following is NOT a mineral?
a. quartz
b. copper
c. granite
d. calcite
e. plagioclase (feldspar)

5. What is the most abundant mineral in the Earth's crust?
a. quartz
b. copper
c. granite
d. calcite
e. plagioclase (feldspar)

6. Soils are composed of layers called _________________. A vertical cross section through all of these layers is called a(n) ________________.
a. sheets, allofact
b. zones, pressure gradients
c. strata, geothermal gradient
d. horizons, soil profile
e. beds, column

7. Exceptionally coarse grained igneous rocks have a ________________ texture.
a. mafic
b. silicic
c. pegmatitic
d. detrital
e. aphanitic

8. Why is productive farmland not produced by clearing tropical and subtropical forests?
a. the soils in those forests are pedocals
b. the soils in those forests are pedalfers
c. the soils in those forests are humus
d. the soils in those forests are bauxite
e. the soils in those forests are laterites

9. Which of the following are near the bottom (low temperature end) of Bowens Reaction Series?
a. olivine
b. amphibole
c. quartz
d. Ca-plagioclase
e. pyroxene

10. Which mineral would you expect to weather most rapidly?
a. olivine
b. amphibole
c. quartz
d. pyroxene
e. Na-plagioclase

11. Which element makes your drinking water "hard"?
a. iron
b. lead
c. calcium
d. sodium
e. potassium

12. Which of the following is located above a "hot spot"?
a. Hawaii
b. Iceland
c. Mt. St. Helens
d. Mt. Etna
e. all of the above

13. Which of the following is an example of a chemical sedimentary rock?
a. limestone
b. sandstone
c. conglomerate
d. shale
e. granite

14. What criteria are used to classify plutons?
a. grain size, mineralogy, and texture
b. chemistry, color, and weight
c. dimensions, odor, and iridescence
d. roundness, sphericity, and weathering
e. size, shape, orientation relative to existing structures

15. The two principle types of weathering are
a. friction and pressure
b. heat and pressure
c. mechanical and physical
d. chemical and mechanical
e. chemical and heat

16. Rocks in which all the grains are the same size are said to be:
a. uniform
b. rounded
c. well disciplined
d. well sorted
e. differentiated

17. Which of the following is false:
a. In near surface environments, rocks of granitic composition begin to melt at about 800 C.
b. The volcanoes that form the Hawaiian Islands are mainly shield volcanoes.
c. Numerous fissure eruptions occur along the ocean ridges.
d. Mt. St. Helens was a relatively small volcano compared to others of the same sort that have occurred around the world.
e. Granite batholiths don't occur along the western margin of North America.

18. The disintegration and decomposition of rock at or near the Earth's surface is called ______.
a. metamorphism
b. sedimentation
c. weathering
d. alteration
e. diagenesis

19. What is chert?
a. a dense fine-grained rock composed of microcrystalline quartz
b. a type of clay mineral typical of desert environments
c. a rock made of volcanic glass
d. the material that makes up most igneous dikes
e. a course carbonate-rich rock typically formed in reef environments

20. Which of the following typically forms in evaporite deposits?
a. gypsum
b. sandstone
c. granite
d. basalt
e. shale

21. What features would you expect in a sedimentary rock composed of material that had been transported a long distance by a river or stream?
a. coarse grain size
b. fine grain size
c. very angular fragments
d. lots of varied mineralogy
e. lots of fossils

22. Which of the following are good ways to prevent soil erosion?
a. maintain ground cover
b. plant wind breaks
c. use contour plowing
d. keep soil rich in humus
e. all of the above

23. In which of the following places is the crust of the Earth very thin, so the mantle is right near the surface?
a. in the centers of old continents
b. along transform faults
c. in subduction zones
d. at hot spots
e. at mid ocean ridges

24. Ruby and sapphire are gems. What mineral are they composed of?
a. quartz
b. beryl
c. corundum
d. diamond
e. amethyst

25. The theory of plate tectonics first became widely accepted in about ____________.
a. the 1960s
b. the 1930s
c. between 1900 and 1910
d. in the 1800s
e. in the 1700s