Problem 3
How do you explain that the oldest large-scale oceanic crust found on Earth dates back to about 180 million years, whereas the oldest continental crust dates back to about 4.4 billion years?
Problem 8
Density is a key component in the behavior of Earth materials and is especially important in understanding key aspects of plate tectonics. Describe three different ways that density and/or density differences play a role in plate tectonics.
