What was the tectonic evolution of western North America beginning with the Permian and through
the Mesozoic? What will be an ideal response?
During the Permian, an island arc and ocean basin formed off western North America, and then an
oceanic plate subducted beneath the island arc. Oceanic and island arc rocks were thrust eastward
against the craton during the Permian-Triassic boundary. In the Early Mesozoic, western North
America became an oceanic-continental convergent plate boundary, with a steeply dipping subduction
zone as North America moved over the Pacific plate.
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Increasing temperatures of earth’s surface and lower atmosphere provide strong evidence that global
warming is happening right now. This evidence includes all of the following except:a. Average earth temperature from land areas and global shipping lanes indicate that average Earth temperature increased 0.74 degrees Celsius during the 20th century. b. Half of the increase in Earth’s average temperature from the 20th century increased during its last 30 years. c. Nine of the ten years during the first decade of the 21st Century were in the top 10 warmest years of a 160-year-long record. d. Earth’s present average temperature is the warmest it has been since 1400, which is as far back as we can go with certainty by direct and indirect evidence. e. During the recent increase in Earth’s temperature the greatest amount of warming occurred during the day near the equator.
When comparing the characteristics of common magmas or lavas, ____
a. ?rhyolite has the lowest water content b. ?andesite has the lowest viscosity c. ?basalt has the highest silicate content d. ?rhyolite has the highest viscosity e. ?basalt has the lowest temperature
The current total world population is ________
A) 5 billion B) 6 billion C) 7 billion D) 8 billion E) 9 billion
In order to reduce your waste disposal footprint, you might ________
A) consider purchasing disposable items B) give attention to reuse, recycle, and reduce C) recycle nothing D) throw away everything E) use organic fertilizers instead of manure or recycled sludge