Ch 10 sect 1 &2

The earth is ______________of years old

• Hundreds

• Millions

• Billions

• Trillions

What type of event usually marks the end of an Era

• A Mass Extinction

• The passing of 250 million years

• An earthquake

• A Volcanic Eruption

What era did trilobites, fishes, and other marine organisms dominate?

• Precambrian

• Paleozoic

• Mesozoic

• Cenozoic

The Law of Superposition states that in undisturbed rock layer

• the older layers of rock are at the bottom

• the older layer of rock are at the top

• the younger layer of rock is at the bottom

• the younger layer of rock is in the middle

How do most fossils form?

• A living thing dies and is buried under sediment

• A living thing is eaten by predators.

• A living thing decomposes due to exposure to air, water, bacteria, and insects.

What things can fossils reveal about Earth?

• How life has changed over time
• All of these answers
• How Earth's climate has changed over time
• How Earth's features have changed over time

This palm tree fossil was found in Alaska. What can you conclude?

• Alaska used to be under water
• Alaska once had a much warmer climate
• Alaska was once an island
• This fossil washed up on the Alaskan shore

These are species that existed on Earth for a short length of time (about 1-10 million years), were abundant, and inhabited many locations.

• index fossils

• key beds

• major geologic events

• unconformities

These are the longest units of geologic time.

• eons

• era

• period

• epoch

Which era lasted the longest?

• Cenozoic

• Mesozoic

• Paleozoic

• Precambrian