Mr. Varner					Name: _____________________________
Mapping activity


Geologic Time: Precambrian Rocks

Objective: To identify and map the oldest rocks in the North American continent.

Fact: Precambrian rocks are those older than 542 million years.

Materials: Geologic History of North America blank map, map of rocks from various eons and eras of time before the Cambrian period.

Procedure:
¥ Go to the Oceanlinks website: http://www.americanroads.us/oceanlinks.html
¥ Click on the link: Map of Precambrian rocks in North America.
¥ Examine the different ages of these ancient rocks from oldest (purple) to youngest (gold).
¥ Label the Geologic Age as "Precambrian" on your outline map.
¥ Color in the region of all Precambrian rocks on your map of North America. You can use any single color for all the colors on the map.

Questions to answer:
1. Where is the largest concentrated area of Precambrian rocks?


2. Name other areas of North America that also have Precambrian rocks.



3. Find the location where you live and mark it on your map. Is your area made of rocks older or younger than 542 million years ago?



4. How do you think the younger rocks were created and became attached to the older Precambrian rocks? Explain using ideas learned when studying plate tectonics and continental drift.