Determining Ages of Rocks 1

: It means identifying which rocks formed first, second, third, and so on and It tells us the sequence in which events occurred, not how long ago they occurred describe the way we compare the positions of people in our family

• Relative age

• Absolute age

The number of years since a rock was formed (specific number)

• Relative age

• Absolute age

How do scientists determine the relative ages of rocks?

• Faults

• Index fossil

• . Igneous rocks

• Radioactive decay (radiometric dating or half life)

• Law of superposition

How do scientists determine the absolute ages of rocks?

• Faults

• Index fossil

• . Igneous rocks

• Radioactive decay (radiometric dating or half life)

• Law of superposition

The rock layers on top are the youngest layers, and the lower rock layers are the oldest layers.

• Faults

• Index fossil

• . Igneous rocks

• Radioactive decay (radiometric dating or half life)

• Law of superposition

cools to become intrusion

• Faults

• Lava

• Magma

• Fossils:

cools to become extrusion

• Faults

• Lava

• Magma

• Fossils:

is a break in the ground caused by Earthquakes

• Faults

• Lava

• Magma

• Fossils:

is younger than the rock it cuts through

• Faults

• Lava

• Magma

• Fossils:

preserved remains or traces of living things, Found in layers of Sedimentary rock Index fossils tell the relative age of rocks

• Faults

• Lava

• Magma

• Fossils: