front 1 Which of the following correctly describes the Atlantic and Pacific continental margins? | back 1 The Atlantic is a passive margin, and the Pacific is an active margin |
front 2 Choose the true statement regarding the continental shelf. | back 2 The shelf represents the flooded portions of continents. |
front 3 Turbidity currents travel from the shelf through __________, creating deep sea fans. | back 3 canyons |
front 4 Relationship of volcanism and seismicity to plate tectonics: | back 4 Volcanism is primarily found at divergent and convergent plate boundaries. Most seismicity occurs along plate boundaries of all three types. |
front 5 If the subduction angle is steep, the overriding plate may undergo __________. | back 5 subduction erosion |
front 6 Which of the following is true regarding shallow subduction angles? | back 6 Sediment and seamounts are scraped from the downgoing plate to produce an accretionary wedge. |
front 7 What happens as plates diverge at an oceanic ridge? | back 7 New oceanic crust and lithospheric mantle are generated by the cooling of molten rock upwelling from the mantle |
front 8 What two layers of the ophiolite sequence are compositionally similar, but formed in different areas with respect to the crust? | back 8 Layer 2: Basalt pillow lavas and Layer 4: gabbro |
front 9 Which of the following contains the entire ophiolite suite, in order from the mantle to the seafloor? | back 9 mantle peridotite |
front 10 What are the features associated with a divergent boundary that is spreading quickly? | back 10 a relatively smooth swell with gentle slopes |
front 11 Which of the following accurately compares the Mid-Atlantic Ridge and East Pacific Rise? | back 11 The Mid-Atlantic Ridge is spreading at a much slower rate than the East Pacific Rise. |
front 12 Name the correct order of rifting events. | back 12 crustal upwarp |
front 13 The Gulf of Aden represents which part of the rifting sequence? | back 13 linear sea |
front 14 The timing of __________ and continental breakup strongly correlate. | back 14 flood basalt formation |
front 15 What feature connects the South American Paraná and African Entedeka flood basalts? | back 15 seamount chains |
front 16 What sequence of rocks would you expect rift valley evolution to produce, from oldest to youngest? | back 16 volcanic rocks |
front 17 Which of the following is a true statement regarding the Farallon Plate | back 17 It was an oceanic plate that used to exist between the Pacific and North American Plates. |
front 18 The plate boundary in the U.S. Pacific Northwest is _____, while most of the California coast is characterized by a _____ plate boundary. | back 18 convergent; transform |
front 19 Which statement regarding Baja Mexico and the city of Los Angeles is correct? | back 19 Both are located on the Pacific Plate |
front 20 Strike-slip faulting of the Queen Charlotte and San Andreas fault systems shows __________. | back 20 a right lateral sense of motion |
front 21 What happened to the Farallon Plate approximately 20 million years ago? | back 21 The San Andreas and Queen Charlotte Faults were established where it was subducted beneath the North American plate |
front 22 Which of the following scenarios could result in the development of a compressional mountain belt? | back 22 two landmasses collide |
front 23 Which geologic features would be present in compressional mountain belts? (Note: There may be more than one answer.) | back 23 folds |
front 24 Which of the following rocks are characteristic of compressional mountain building? | back 24 schist |
front 25 Using the map provided in Figure 1, in which province would the Rocky Mountains of the United States be located? | back 25 young mountain belts |
front 26 Which of the following orogenies helped to create the Appalachian Mountains? | back 26 Taconic, Acadian, and Alleghanian |
front 27 Which event marked the creation of the supercontinent Pangaea? | back 27 The Iapetus Ocean closed during the Alleghanian Orogeny. |
front 28 Which of the Appalachian Mountain Belt Provinces are visible in the circled area of Figure 1? | back 28 Valley and Ridge |
front 29 Which of the following geographic provinces is the newest addition to the North American continent? | back 29 Coastal Plain |
front 30 Which mountain range marks the boundary between the Indian and Eurasian Plates? | back 30 Himalayas |
front 31 What kind of tectonic boundary is currently responsible for creating the Himalayas? | back 31 Continent-Continent Convergent Boundary |
front 32 What geologic features were created in the Eurasian Plate when India underthrust beneath it? | back 32 thrust faults |
front 33 As India moves northward, China and Southeast Asia are being relocated to the east and southeast because of "escape tectonics." What feature is allowing them to "escape"? | back 33 strike-slip faults |
front 34 When the Indian Plate collided with Eurasian Plate, why didn't it subduct? | back 34 The Indian Plate is too buoyant. |
front 35 A terrane is __________. | back 35 a mass of rock that formed elsewhere and was added to a continent |
front 36 Which tectonic boundary is associated with the addition of terranes to a continent? | back 36 convergent boundary |
front 37 What is the name of the process by which terranes are added to continents? | back 37 accretion |
front 38 Using the map in Figure 1, determine which of the named terranes accreted earliest to North America. | back 38 Yukon-Tanana |
front 39 The map in Figure 2 is a cross-section of the North American continent 600 million years ago and after the break-up of Pangaea approximately 200 million years ago. Which material(s) had been accreted to North America as terranes? | back 39 Iapetus Ocean Island Arc and sediments |