The continental crust of the Pacific Northwest and Alaska are much different from the rest of the United States. What process would account for these varied differences?
Plateaus, isolated segments of seafloor, ocean ridges, ancient island arcs, and parts of continental crust are rafted along with a plate and scraped off when the plate is subducted. Theses sheared off faces of subducted plates are uplifted and called terranes. The thickness and low density of terranes prevent their subduction. The Pacific Northwest of North American and most of Alaska are composed of this quilt-like assemblage of material, some of which has evidently arrived from thousands of kilometers away.
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We know from the second law of thermodynamics that some of the high-quality energy in each step of processing is
A. wasted and degraded to lower-quality energy. B. upgraded to higher-efficiency energy. C. maintained at the same level of quality. D. destroyed completely. E. converted into renewable energy.
The characteristics by which urban minority groups are typically defined and congregate typically include
A) race. B) language and religion. C) nationality. D) sexual orientation or lifestyle. E) race, language, religion, nationality, and sexual orientation or lifestyle.
By international agreement, what is the general term for all hurricane-type storms that originate over tropical waters?
A) typhoons B) hurricanes C) tropical storms D) tropical cyclones
The hardest mineral has a hardness of ________ on Mohs' relative hardness scale.
A. 1 B. 10 C. 100 D. 1000 E. 10000