Page 116 - Science Course 3 (Book 2)
P. 116
Mo11-L2b: How to Determine the Relative Ages of Rocks?
Index fossils represent species that existed on Earth
for a short length of time, were abundant, and Key Concept
inhabited many locations. How to Determine the Relative Ages of Rocks?
How are index fossils useful in relative-age dating?
When an index fossil is found in rock layers at
different locations, geologists can infer that the
layers are of similar age.
SUMMARY
How to Determine the Relative Ages of Rocks?
The rock record is incomplete because some of it has eroded away.
Geologists f ll in gaps in the rock record by correlating rock layers.
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