Geology
Explain radiometric dating in YOUR OWN WORDS
Radiometric dating analyzes the chemical composition of a rock and is able to figure out the exact age of the rock.
OR
Radiometric dating looks at what the rock is made of and can figure out the age of the rock.
Fossils found in layers of rock are_____ for the events in Earth's history.
Evidence
Top
How old is the earth? How do you know?
4.6 billion years old. Scientists found the oldest rock using radiometric dating.
What is a Paleontologist?
A person who studies fossils.
list 2 things scientists CAN find out just by looking at the layers.
List 2 things they can NOT tell just by looking at these layers.
1. Which fossil is older or younger
2. Which layer is older or younger
1. We can NOT tell the exact age of fossil
2. We can not tell the exact age of the layers
A geologist is a scientist that…
Studies the Earth and its rocks
A paleontologist found a fish skeleton fossil in desert strata. What was the land like when that layer formed? Explain how you know this.
If they found a fish that means there was once water - lake, ocean or river when that layer formed.
How do scientists determine the absolute age of rock.
Radiometric dating
What is the difference between relative age and absolute age?
Relative age just tells us what is older and younger
Absolute age tells us EXACT age.
What is the difference between a body fossil and a trace fossil?
Body fossil - the actual body parts of the organism - teeth, bones
Trace fossil - evidence the animal was there - footprints, nest, tracks…
What can scientists learn about the Earth by looking at strata?
Scientists can learn which layer is older and which is younger. They can also learn what the environment was like for each layer of rock.
How has Earth changed since it was formed?
The Earth has changed a lot since it was formed. There have been many different plants and animals on Earth. The environment and climate has changed as well.
How do fossils help scientists learn about the Earth?
Fossils tell us what animals and plants lived in the past and are no longer alive.
The law of superposition states that...
The older rock layers are on the bottom and the younger rock layers are on the top.