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Zones-Of-Crustal-Activity-Questions 1. Which two features are commonly found at divergent plate boundaries? A) mid-ocean ridges and rift valleys B) wide valleys and deltas C) ocean trenches and subduction zones D) hot spots and island arcs 2. Which coastal area is most likely to experience a severe earthquake? A) east coast of North America B) east coast of Australia C) west coast of Africa D) west coast of South America 3. The diagrams below show four major types of fault motion occurring in Earth’s crust. Which type of fault motion best matches the general pattern of crustal movement at California’s San Andreas fault? A) B) C) D) 4. The edges of most lithospheric plates are characterized by A) reversed magnetic orientation B) unusually rapid radioactive decay C) frequent volcanic activity D) low P-wave and high S-wave velocity Base your answers to questions 5 through 8 on the map below which shows mid-ocean ridges and trenches in the Pacific Ocean. Specific areas A, B. C, and D are indicated by shaded rectangles. 5. Which map best shows the direction of movement of the oceanic crustal plates in the vicinity of the East Pacific Rise (ridge)? A) B) C) D) 6. The crust at the mid-ocean ridges is composed mainly of A) granite B) shale C) basalt D) limestone 7. Movement of the crustal plates shown in the diagram is most likely caused by A) the revolution of the Earth B) the erosion of the Earth's crust C) shifting of the Earth's magnetic poles D) convection currents in the Earth's mantle 8. Mid-ocean ridges such as the East Pacific Rise and the Oceanic Ridge are best described as A) mountains containing folded sedimentary rocks B) mountains containing fossils of present-day marine life C) sections of the ocean floor that contain the youngest oceanic crust D) sections of the ocean floor that are the remains of a submerged continent 9. The movement of tectonic plates is inferred by many 11. Base your answer to the following question on the scientists to be driven by diagram below which shows a coastal area with a mountain range and a portion of the ocean floor. A A) tidal motions in the hydrosphere turbidity current through a submarine canyon has B) density differences in the troposphere formed a fan-shaped sediment deposit on the ocean C) convection currents in the asthenosphere floor. D) solidification in the lithosphere 10. Letters A through D shown on the map below are locations on Earth's surface. In which region of the ocean is the submarine canyon located? A) tidal zone B) continental margin C) deep ocean basin D) mid-ocean ridge 12. Active volcanoes are most abundant along the Which location is closest to a major zone of frequent A) edges of tectonic plates earthquakes and volcanic activities? B) eastern coastline of continents C) 23.5° N and 23.5° S parallels of latitude A) A B) B C) C D) D D) equatorial ocean floor 13. The formation of the Canary Islands was primarily caused by their location near a A) subduction zone B) mantle hot spot C) divergent boundary D) transform fault 14. Which surface feature was produced by crustal movements at a transform plate boundary? A) East African Rift B) Aleutian Trench C) Tasman Hot Spot D) San Andreas Fault 15. Which of the following is located at a converging plate boundary? A) Southwest Indian Ridge B) Iceland Hotspot C) Marianas Trench D) Sandwich Plate Base your answers to questions 16 through 18 on the diagram below which is a cross section of the major surface features of the Earth along the Tropic of Capricorn (23½º S) between 75º W and 15º E longitude. Letters A through G represent locations on the Earth's crust. 16. A mid-ocean ridge is located near position A) A B) E C) C D) D 17. Which diagram shows the most probable direction of movement of the crustal plates and the inferred mantle convection currents under position A? A) B) C) D) 18. What is the approximate width of the Atlantic Ocean at this location? A) 1,200 km B) 2,600 km C) 3,500 km D) 4,400 km 19. Hot springs on the ocean floor near the midocean ridges provide evidence that A) convection currents exist in the asthenosphere B) meteor craters are found beneath the oceans C) climate change has melted huge glaciers D) marine fossils have been uplifted to high elevations 20. The map below shows California and a section of the San Andreas Fault. What is the primary geologic process occurring along the San Andreas Fault? A) transform movement B) spreading movement C) subduction D) convergence 21. Base your answer to the following question on the map below. Letters A through F are locations on Earth’s surface. Which location is closest to a divergent plate boundary at an oceanic ridge? A) A B) B C) C D) E Base your answers to questions 22 and 23 on the block diagram below, which shows a tectonic plate boundary. 22. Which tectonic plate boundary is best represented by this diagram? A) Nazca Plate and Pacific Plate boundary B) Scotia Plate and South American Plate boundary C) Juan de Fuca Plate and North American Plate boundary D) Antarctic Plate and Indian-Australian Plate boundary 23. Compared to the oceanic crust, the continental crust is A) more dense and more mafic B) more dense and more felsic C) less dense and more mafic D) less dense and more felsic Base your answers to questions 24 and 25 on the map below. Dots on the map show the distribution of major earthquake epicenters. The shaded circle labeled A represents a location on Earth's surface. 24. Location A is best described as an area that is A) within a rift valley at a mid-ocean ridge B) at the boundary between two diverging plates C) within a deep-sea trench between two converging plates D) above a mantle hot spot near the center of a crustal plate 25. Which conclusion can best be inferred from the data shown on this map? A) Earthquakes generally are evenly distributed over the surface of Earth. B) Most earthquakes occur west of the Prime Meridian and north of the Equator. C) Most earthquakes are concentrated in zones along plate boundaries. D) Most earthquakes occur on continents. 26. Earth's internal heat is the primary source of energy 28. Crustal disturbances such as earthquakes and that volcanic eruptions are best described as A) warms the lower troposphere A) events that are cyclic and predictable B) melts glacial ice at lower altitudes B) events that are usually related and cannot be C) moves the lithospheric plates predicted with accuracy D) pollutes deep groundwater with radioactivity C) unrelated events that follow no pattern 27. On which plate is the Hawaii Hot Spot located? D) phenomena seldom found in the same regions A) South American B) Antarctic C) Nazca D) Pacific 29. Which cross section best represents the convection currents in the mantle beneath the Peru-Chile Trench? A) B) C) D) 30. Where does most present-day faulting of rock occur? A) in regions of glacial activity B) in the interior areas of continents C) at locations with many lakes D) at interfaces between moving parts of the crust 31. What type of plate boundary exists between the African Plate and the Antartic Plate? A) convergent B) transform C) divergent D) complex 32. Base your answer to the following question on the map below, which shows the tectonic plate boundaries near the East African Rift. Arrows show relative tectonic plate movement. A region of Africa is crosshatched. What appears to be happening to the crosshatched region of eastern Africa? A) A folded mountain range is forming as this region collides with the rest of Africa. B) Several volcanic mountains are forming as the rest of Africa subducts under this region. C) This region is moving eastward relative to the rest of Africa. D) This region is moving northward relative to the rest of Africa. Base your answers to questions 33 through 35 on the information, map, and cross section below. The map represents a portion of Earth's surface in the Pacific Ocean. The positions of islands, earthquake epicenters, active volcanoes, and the Tonga Trench are shown. Lines of latitude and longitude have been included. The cross section shows earthquakes that occurred beneath line XY on the map. Depth beneath Earths surface is indicated by the scale along the left side of the cross section, as are the range of depths for shallow, intermediate, and deep earthquakes. Distance from the trench is indicated by the scale along the bottom of the cross section. 33. Which cross section has arrows that best represent the relative motion of the crustal plates along the Wadati-Benioff zone beneath the Tonga Trench? A) B) C) D) 34. The greatest number of earthquakes shown in the cross section occurred A) at sea level B) between sea level and a depth of 100 km C) at a depth between 100 and 300 km D) at a depth between 300 and 600 km 35. The Tonga Trench is located at the tectonic boundary between the Pacific Plate and the A) Antarctic Plate B) Philippine Plate C) Indian-Australian Plate D) Nazca Plate 36. According to the plate tectonics theory, the 38. The diagram below represents a cross section of the Peru-Chile Trench and the Andes Mountains formed Earth's crust at a location where an oceanic plate is along the west coast of South America because the converging (colliding) with a continental plate.
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