Discuss how oceanic crust forms. What process generates the necessary magma? Also, be sure to discuss ophiolite sequences and discuss how the formation of each layer contributes to the formation of the crust
What will be an ideal response?
Answer: Magma is generated through decompression melting. This magma rises to the surface to fill in the gaps between the diverging tectonic plates. Fractures created by tension provide pathways for magma to rise and spill out on to the ocean floor, creating the pillow basalts. The fractures the basalt moved through become sheeted dikes as the magma cools. Meanwhile, the magma that remained in the magma chamber forms the gabbro bodies.
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Paleomagnetism measures the ____________________ and ____________________ of remnant magnetism in rocks. What will be an ideal response?
Briefly describe the hydrologic cycle
What will be an ideal response?
What partly explains the seabed topography we observe?
a. The jostling due to plate tectonics. b. The greater density of continental lithosphere. c. The presence of continental margins. d. The little interaction with the asthenosphere.
Based on the typical pattern of lake-effect snowfall near the Great Lakes, one can conclude that wintertime winds in this region are typically [INSERT FIGURE 7-13. NO CAPTION]
A) northerly B) easterly C) southerly D) westerly