Briefly explain the difference between the tectonic setting of shield areas during the Precambrian and since the onset of the Phanerozoic
During the Precambrian, the areas that are now part of the shield were tectonically active with volcanism, metamorphism, and folding and faulting. During that time, continents grew by accretion. Since the beginning of the Phanerozoic, these areas have been tectonically inactive and have been eroded to topographically flat, stable areas.
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The 2011 nuclear power accident in Japan
A. was a result of global warning B. increased the public confidence in nuclear power safety and regulation C. exposed several design flaws and a failure to develop worst-case scenarios D. will not lead to increased cancers due to the quick and efficient clean-up response E. is no longer leaking nuclear waste into the ocean
How does the strength of continental crust vary with depth?
A) Rocks become stronger with depth and then get weaker deep in the crust. B) Rocks weaken with depth and then get stronger deep in the crust. C) Rocks systematically get stronger from the surface to deep in the crust. D) Rocks systematically get weaker from the surface to deep in the crust.
Phytoplankton are
a. plants. d. carnivore-scavengers. b. animals. e. heterotrophs. c. carnivores.
Ignoring migration, the age structure diagram of a human population likely to maintain a relatively stable size will have what shape?
a. Both an inverted pyramid and a rectangle tapering toward the top result in a population that remains stable in size. b. a rectangle tapering toward the top c. pyramid d. inverted pyramid e. Both a pyramid and a rectangle tapering toward the top result in a population that remains stable in size.