Explain the origin of oceanic crust
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Answer: It is perhaps a bit surprising that the formation of the basaltic oceanic crust, despite its relative inaccessibility beneath the oceans, is better understood than that of continental crust. The recipe for making basalt?partial melting of mantle peridotite produces basaltic magma. The non-melted peridotite minerals remain behind to make up the mantle part of the lithosphere. Oceanic crust, therefore, simply is extracted from the mantle by partial melting and crystallization. This melting and extraction process is witnessed today at divergent plate boundaries and where mantle plumes generate accumulations of basalt at places such as Hawaii.
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What role does temperature play in metamorphism?
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What solid materials would have existed in the vicinity of Earth as the solar nebula cooled?
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Which of these Köppen climate classes is defined as an area that does not have a month with an average temperature exceeding 10 °C (50 °F)?
a. mesothermal b. polar c. tropical d. microthermal e. highland
Africa's best example of an exotic river is the ________
A) Nile B) Amazon C) Orange D) Rhine E) Congo