GEOL 101 Chapter 16

When landmasses were forced together to create the first continents, why didn't the continents subduct?

Continental crust is thicker and has a lower density.

What feature, marked with an A in Figure 1, is responsible for creating the oceanic plateau?

Mantle plume

Which region of North America has the oldest parts of the continent?

Northern Canada

How was material generated to create continental masses?

Partial melting of subducting plates.

Which of the geologic provinces in Figure 1 might have been added in the time leading up to the formation of Pangaea?

Appalachian Province

Antarctica has been continuously glaciated for the last _________ years.

30 million

How would sediments caught between two accreting landmasses appear? (What feature or features would you expect to see?

Folds and foliated rocks

Which geologic event was responsible for adding the Grenville Province to North America approximately 1.2 billion years ago?

Formation of Rodinia

Using Figure 2, determine when the majority of the African craton had been formed.

Proterozoic Eon

How does the West Wind Drift contribute to the glaciation of Antarctica?

The West Wind Drift is a cold water current that circles Antarctica.

What geologic features created the earliest fragments of continental crust?

Volcanic island arcs

What would happen if the West Wind Drift stopped circling Antarctica?

Warmer water would flow down toward Antarctica, resulting in a warmer climate.

What is the name of the current that is blanked out in Figure 1?

West Wind Drift