Grade 7 Unit 6 History of the Earth

Examine rocks collected in my backyard

Analyze maps of all known fossil sites in the United States

Test the rate of decay of specific elements in rock samples

Explore leaves embedded in ash from recent volcanic eruptions

Predatory birds carried prey to their inland nests and discarded the bones on the ground.

Some ancient marine organisms had the ability to walk on land and likely migrated inland

Ocean levels were once much higher than they are today so inland areas were under water.

Strong winds carried marine organisms inland where they were buried and fossilized under layers of sediment.

The Law of Superposition is an explanation relating to the sequence of disturbed rock layers

The Law of Superposition is an observable fact relating to the sequence of undisturbed rock layers.

The Law of Superposition is a study of past events preserved in disturbed rock layers and their exceptions. 

The Law of Superposition is a theory that may be replaced by an improved theory if new discoveries are made relating to the sequence of undisturbed rock layers..

A sedimentary rock layer is between 10,000 and 10,500 years old.

A sedimentary rock layer is younger than the existing layer below it.

A sedimentary rock layer is 20,000 years old because it is a scientific law.

A sedimentary rock layer contains fish fossils, but the layers above and below it do not contain any fossils.