Name _____________________________________________
Period _____
Relative Dating and Rock Layers
1. How old is our Universe? _______________________
2. How old is Earth? _____________________________
3. Earth was once made of molten _________ and
__________, eventually cooling to form ____________
rock. Weathering, _________________, Compaction,
Cementation, Heat, and _______________ eventually
formed the rocks that cover our Earth’s surface.
4. What we know about Earth’s history comes from
studying its __________ , rock _______________,
rock ___________and even the rocks from
______________
Meteorites
5. All meteorites formed about the same time that ___________ formed, so studying
them helps us study Earth.
6. Meteorites have not been affected by ____________, weathering or other
forces the way Earth’s rocks have.
Studying Earth’s Rocks
7. When rocks form, the _____________ ones can be found beneath
_____________ rocks.
8. Most fossils are found in _______________ rock layers.
9. Why? Heat, pressure, and _____________ would probably destroy
fossils during the formation of ______________ and ____________rocks
10. Sedimentary rocks, and the ________________ they trap, often follow a similar
pattern, oldest rocks are found on the
__________________.
11. Digging through the _______________ of rocks, helps us
understand more about the history of Earth.
12. The __________________ Canyon (Arizona) was carved
by the _______________ river, exposing millions of years
worth of rock layers.
13. Sometimes, the rock layers aren’t always
___________________
14. And sometimes _____________ fossils are
found high in the ____________________
15. Turns out, our Earth’s surface is constantly
____________, changing, and
_______________________ and the layers
get _________________ around.
16. Only in the last ____________ years, have we begun to understand the structure
formation and _______________ of our Earth.
To figure out the ages of rocks and their fossils, ______________ rely on a few rules…
Law of Superposition
In any undisturbed rock, the _________________ layer is at the
bottom and the _____________________ layer is at the top.
The Cross Cutting Law
Any feature that ___________ _________________ a body of
rock is ______________ than the body of sediment or rock it
cuts across.
The Law of Inclusions
If one rock layer contains _________________ (inclusions) of
another rock layer, it must be _______________________ than
the fragments of rocks it contains.