EASC100: EXAM1 (07) Lithosphere and Hydrosphere Name: 1. Why do Mercury and the Moon lack an atmosphere? A) They formed after all the gas had been used up. B) They are so cold that all their gases have frozen into deposits below their surface. C) They formed before the solar nebula had captured any gas. D) They are so small that their gravity is too weak to retain an atmosphere. 2. Felsic rocks A) are rich in feldspar and silica. B) have high concentrations of silica and aluminum. C) usually contain abundant concentrations of quartz, feldspar, biotite and/or muscovite. D) all of the above. 3. The S-wave shadow zone is evidence that: A) it is very hot near the core. B) the inner core is solid. C) the outer core is composed of iron and nickel oxides. D) the outer core is liquid. 4. The physical evidence that the core is composed mostly of iron is: A) scientists have sampled the core and determined its composition. B) volcanoes regularly erupt material from the core to the surface. C) the known mass of Earth requires material of high density at the core. D) none of these 5. The velocity of seismic waves varies through Earth because: A) the composition of rocks varies within the Earth. B) the elastic behavior of rocks varies within the Earth. C) density of rocks varies within the Earth.
6. Convection is likely occurring (in): A) throughout the Earth. B) both the mantle and the outer core. C) the outer core. D) the mantle. 7. The interior composition and structure of Earth have been deduced in part from: A) analyses of the behavior of seismic waves. B) studies of meteorites. C) deep drilling projects. 8. Wegner assembled the continents into a single supercontinent was called: A) Pangea. B) Gondwanaland. C) Glossopteris. D) Laurasia 9. Which of the following features would you expect to find at an ocean-continent convergent boundary? A) earthquakes B) deep ocean trench C) volcanic mountain chain 10. Which of the following would you expect to find at a continent-continent convergent boundary? A) deep ocean trench B) volcanic mountain chain C) suture zone
11. Which of the following was not used by Wegener as evidence of continental drift? A) magnetic anomalies on the seafloor B) the geometric fit of the continents C) evidence of glaciation on widely separated continents D) fossils that were common to many continents 12. The East African Rift is an example of: A) a divergent plate boundary. B) an ocean-ocean convergent boundary. C) an ocean-continent convergent boundary. D) a continent-continent convergent boundary. 13. Which is not a fine-grained rock type? A) granite B) andesite C) basalt D) rhyolite 14. Fragments of country rock surrounded by igneous rock are known as: A) meteorites B) xenoliths C) exoliths D) lithographs 15. The difference in minerals among plutonic rocks is caused by: A) different chemical compositions of the magma. B) different crystallization temperatures and temperature histories. C) magmatic differentiation through removal of early-formed crystals. 16. The two important criteria used for igneous rock classification are: A) texture and mineral composition. B) temperature and viscosity. C) mineral composition and temperature. D) texture and temperature.
17.A rock type with mineral crystals too small to be seen and low temperature minerals is: A) granite. B) andesite. C) rhyolite. D) gabbro. 18. The silicon-oxygen tetrahedron is: A) the building block of the silicate minerals. B) composed of 4 oxygen atoms surrounding 1 silicon atom. C) composed of the two most abundant elements on Earth. 19. Which of the following is considered a physical property of minerals? A) luster B) hardness C) streak are physical properties of minerals. 20. Volcanic eruptions can affect climate because: A) they are tall mountain peaks. B) they inject water vapor to make clouds and rain. C) they heat the atmosphere. D) inject particles into the stratosphere, thus reducing sunlight. 21. Magma with a low silica content tends to be: A) very glassy. B) very viscous. C) high in volatiles, i.e. gases D). All of the above 22. Which of the following does not affect the viscosity of magma? A) amount of gases B) silica content C) temperature D) All of these affect the viscosity of a magma.
23. Which of these is not a common gas in magma? A) methane B) sulfur dioxide C) carbon dioxide D) water vapor 24. Mafic igneous rocks contain: A) about 80% silica. B) about 70% silica. C) about 60% silica. D) about 50% silica.