Assume the Mid-Continental Rift were to reactivate and divergence were to occur. What sequence of events would unfold as rifting began and what would eventually happen to the landmass?
What will be an ideal response?
Answer: The continent would stretch and thin. Soon, faulting and fracturing would occur as a large rift valley bounded by normal faults was created. Decompression melting would generate magma, which would migrate upward through the fractures to create sheeted dikes and flood basalts. Water would also move along these fractures, creating a chain of lakes. Eventually, the entire floor of the rift valley would be covered by basalts, and the valley would open up and let in the sea, completing the separation of the landmass.
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When a court hearing a case orders the defendant to stop whatever action is causing concern, it is called a(n) ____.
A. injunction B. subpoena C. ruling D. appeal E. preliminary decision
Which of the following best defines a mineral and a rock?
A) A mineral consists of its constituent atoms arranged in a geometrically repetitive structure; in a rock, the atoms are randomly bonded without any geometric pattern. B) A rock consists of atoms bonded in a regular, geometrically predictable arrangement; a mineral is a consolidated aggregate of different rock particles. C) In a mineral the constituent atoms are bonded in a regular, repetitive, internal structure; a rock is a lithified or consolidated aggregate of different mineral grains. D) A rock has an orderly, repetitive, geometrical, internal arrangement of minerals; a mineral is a lithified or consolidated aggregate of rocks.
An ice storm can form when a ____
a. layer of cold air and a layer of warm air mix between the clouds and the ground b. layer of cold, dry air lies over a layer of warm air c. layer of cold, moist air lies over a layer of warm air d. layer of cold air lies under a layer of warm, dry air e. layer of cold air lies under a layer of warm, moist air
Auroras are seen
a. ?in the Northern Hemisphere only. b. in the Southern Hemisphere only. c. ?in both the Northern and Southern Hemispheres at high latitudes. d. ?in both the Northern and Southern Hemispheres near the equator. e. ?everywhere on Earth