SLIDESQUESTIONS49. How were most people killed after the 1883 eruption of Krakatoa?57. Which of the following cities has the highest seismic risk?PHYSICAL GEOLOGY GEOSC 001 (BRALOWER) Final 12/17/04 B MULTIPLE CHOICE QUESTIONS Please answer the following questions on a computer grading sheet. You must correctlyfill out the identification sections on your computer grading sheet to receive any credit.SLIDES1. What is this rock?A. GraniteB. SandstoneC. GneissD. BrecciaE. Basalt2. What is shown here?A. Pyroclastic rocksB. Black smokersC. Pillow lavasD. LaharsE. Welded tuf3. What type of volcanic event caused this scene?A. A laharB. A nuée ardenteC. A plinian cloudD. A dust stormE. An ash fall eruption4. What is shown here?A. A normal faultB. A reverse faultC. An angular unconformityD. A thrust fault5. What caused this damage?A. VolcanoesB. SlidarsC. LaharsD. TsunamiE. Liquefaction6. What is this feature?A. A barrier islandB. A headlandC. A stackD. A tomboloE. A spit7. What is shown here?A. Glacial striationsB. An eskerC. MoraineD. A kettleE. A drumlin8. What is shown here?A. Glacial striationsB. An eskerC. MoraineD. A kettleE. A drumlinQUESTIONS9. Which of the following formed last?A. AtmosphereB. OceansC. Core10. The age of the Earth is closest to:A. 400 billion yearsB. 210 billion yearsC. 105 billion yearsD. 5 billion yearsE. 500 million years11. Which of the following statements is true regarding the Earth just after itsformation?A. The oceans were teaming with lifeB. Giant mantle plumes produced molten rock all over the Earth’s surfaceC. Active radioactivity produced a lot of heatD. The gravitational field was non-existentE. The rotation around the sun was much slower than today12. What was Pangea?A. An Archean terrane in North AmericaB. A supercontinent that existed about 250 million years agoC. The Appalachian mountain belt after the Acadian orogeny D. A giant early reptile predatorE. A metamorphic rock that no longer is produced at Earth’s P and T conditions13. Why is Apparent Polar Wander apparent?A. Because the magnetic poles are wanderingB. Because the geographic poles are movingC. Because the magnetic poles are reversingD. Because the continents are drifting14. What is the origin of the Earth’s magnetic field?A. The huge biomass of magnetotactic bacteriaB. Motions of large plates made of iron rich rocksC. Mantle plumes that rotateD. Motions of fluid iron in the outer core15. The aesthenosphere can best be described by which of the following statements?A. The rigid layer comprising the plates including the crust and upper mantleB. The rigid layer beneath the crust, including part of the upper mantleC. The rigid, lower part of the mantle, below 250 km depthD. The partially molten layer comprising the upper mantle between 100 and 350 km depth16. Which is closest to the thickness of the crust under the Himalayas?A. 5 kmB. 10 kmC. 20 kmD. 80 kmE. 150 km17. Convergent boundaries are:A. Places where two plates move towards one anotherB. Locations with massive volcanism such as HawaiiC. Linear oceanic mountain chains where new oceanic crust is formedD. Locations where continental crust descends into the mantleE. Where two plates move along side one another in a transform orientation18. Which of the following are normally associated with subduction zones?A. TrenchesB. GrabensC. Transform faultsD. Black smokersE. Sheeted dikes19. What are back arc basins?A. Basins that lie between trenches and accretionary prismsB. Basins that lie between trenches and island arcsC. Basins that lie between island arcs and the continentD. Basins that lie between accretionary prisms and island arcs20. What are triple junctions? A. The place where three ocean basins meetB. Upwarped crust with normal faults and dikesC. The place where a subduction zone and a transform boundary meetD. Three-armed rift systems formed in the early stages of riftingE. Locations of mature ocean basins producing crust by spreading21. Which of the following was formed by a hotspot?A. JapanB. Puerto RicoC. HawaiiD. EnglandE. Cuba22. How did the Himalayan Mountains form?A. Subduction of the Pacific Plate under the Eurasian PlateB. Collision of India and EurasiaC. Collision of India and AfricaD. Extension of India prior to continental break-up23. Which of the following IS part of the definition of a mineral?A. It is rareB. It is composed of more than one diferent atomC. It forms from a liquidD. It is a naturally occurring substance.E. It is indestructible24. What is the formula of calcite?A. SiO2B. CaCO3C. FeSD. CaSO4E. CaPO425. How is granite generated most commonly? A. Wet melting of andesite in a subduction zone setting.B. Dry melting of peridotite at divergent margins.C. Wet melting of basalt at mid-ocean ridges.D. Partial melting of continental crust 26. What minerals are typically found in a granite?A. Olivine, pyroxene and amphiboleB. Quartz, mica, K-feldspar and amphiboleC. Olivine, quartz, mica and Ca-rich plagioclaseD. Pyroxene, mica, Ca-rich plagioclase27. What is the continuous side of Bowen’s reaction series?A. Ca-rich to Na-rich plagioclase feldsparB. Quartz to micaC. Olivine to pyroxeneD. Pyroxene to amphiboleE. Amphibole to mica28. Porphyritic texture is:A. Large phenocrysts in a fine-grained groundmassB. Characteristic of very slow coolingC. Ultra-fine grained crystalsD. Uniformly coarse-grainedE. Characteristic of cooling in the presence of fluids29. Which of the following is an important part of partial melting?A. Magmas crystallize three minerals simultaneouslyB. Crystallized minerals are removed from the magma changing its compositionC. Magmas are fractionated by mixing togetherD. Diferent proportions of rocks are melted forming diferent compositionsE. Part of a magma is erupted after a fraction of it has crystallized30. What is a pyroclastic rock?A. Another name for a lavaB. A coarse-grained plutonic rockC. A rock made of material exploded out of a volcanoD. A solidified mudflowE. A rock made of ultra large crystals that crystallized in the presence of fluids31. What is a batholith?A. A thrust faultB. A large body made of plutonic igneous rockC. A volcano that is blocked by viscous lavaD. A lake in the middle of a crater32. What is the typical geothermal gradient in the crust and upper mantle?A. 0-5o/C B. 20-25o/CC. 100-200o/CD. 500-750o/C33. Which of the