SOLVED

21) A transform plate boundary is characterized by ________. A) stratovolcanoes on the edge of a plate and shield volcanoes on the adjacent plate B) two converging oceanic plates meeting head-on and piling up into a mid-ocean ridge C) a divergent boundary where the continental plate changes to an oceanic plate D) a deep, vertical fault along which two plates slide past one another in opposite directions 22) Which one of the following is an important fundamental assumption underlying the plate tectonic theory? A) Earth’s magnetic field originates in the outer core. B) Earth’s diameter has been essentially constant over time. C) Radioactive decay slows down at the extreme pressures of the inner core. D) Earth’s ocean basins are very old and stable features. 23) The modern-day Red Sea is explained by plate tectonics theory because it is ________. A) a tiny remnant of a once immense ocean that was closed as Africa moved Asia B) the site of a transform fault along which Arabia is moving away from Africa C) a rift zone that may eventually open into a major ocean if Arabia and Africa continue to separate D) a rare example of a two-continent subduction zone where the African continental plate is sinking under the Arabian continental plate 24) The volcanoes and deep valleys of east Africa are related to a ________. A) continental rift along which parts of the African continent are beginning to slowly separate B) fault allowing Arabia to slip westward past east Africa and penetrate into Turkey C) transform fault aligned with the Red Sea carrying the Arabian and African blocks in opposite directions D) continental collision zone between Africa and the Zagros Mountains along the southern margin of Eurasia 25) The Aleutian Islands occur at a ________. A) convergent boundary on a volcanic arc above a northward-subducting Pacific plate B) transform boundary where North America has moved towards Alaska C) divergent boundary where shield volcanoes are forming D) convergent, continental margin with uplifted fault blocks, much like those of the Basin and Range Province 26) Deep-oceanic trenches are most abundant around the rim of the ________ ocean basin. A) Atlantic B) Indian C) Arctic D) Pacific 27) ________ first related the symmetrical magnetic patterns in seafloor basalts to seafloor spreading at a mid-ocean ridge. A) Evans and Novak B) Vine and Matthews C) Matthews and Marks D) Wegener and Wilson 28) Early results of the Deep Sea Drilling Project clearly justified the conclusion that ________. A) the oceans have not always contained most of Earth’s water B) the ocean basins are relatively young; most ocean basin rocks and sediments are Cretaceous or younger in age C) Proterozoic rocks are found only as seamounts in the deepest parts of the ocean basins D) the youngest sediments were deposited directly on the oldest seafloor basalts