You have been hired as a tour guide for the American Museum of Natural History in New York City. The museum has recently acquired a piece of the Acasta Gneiss, dated over 4 billion years old, and found in the Northwest Territories, Canada. The people on your tour are always asking the same questions:

1. How can scientists figure out how old this rock is?

2. What is “gneiss?”

3. Why is this type of rock rare on Earth’s surface?

4. Why is this continental rock so old compared to oceanic rocks?

Answer rating: 100% (QA)

1 The age of this rock has been calculated the use of gear of geochemistry In this rock there may be ... View the full answer