What is the evidence that plates move apart at divergent plate boundaries?
What will be an ideal response?
Answer: Plates move apart at divergent plate boundaries by the process of seafloor spreading, which creates a new, mafic oceanic crust and mantle. Abundant earthquakes, basaltic volcanic activity, high heat flow, high seafloor elevation, and a seismically slow upper mantle confirm plate tectonics predictions for mid-ocean ridges. As predicted by the seafloor spreading hypothesis, magnetic polarity of seafloor crust, along with radioactive isotope ages, demonstrates that oceanic crust is progressively older at greater distances from mid-ocean spreading ridges. Divergent plate boundaries can originate within continents to form rift valleys. Persistent extension along a rift valley causes the lithosphere to break into two continental fragments. Not all rift valleys extend sufficiently to form new continents and plate boundaries.
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Global precipitation has increased as temperatures increased over the last century.
Answer the following statement true (T) or false (F)
Briefly describe chemical weathering, providing examples of several chemical weathering processes
What will be an ideal response?
Of the following, which is most useful for observing regions where there are no clouds?
A) radar B) infrared satellite radiometry C) visible satellite radiometry D) water vapor satellite radiometry E) carbon dioxide satellite radiometry
Earth systems resist change but there are times when the system can change abruptly or become unstable. This is known as a _______.
a. human mistake b. negative feedback loop c. equilibrium condition d. tipping point e. quantam moment