Geologic History Assessment

Which layer is the oldest?

• D
• C
• B
• A

Which of the following is the oldest?

• Layer L
• Intrusion D
• Intrusion H
• Layer E

What is the time needed for half of a sample of a radioactive substance to undergo radioactive decay?

• Half life
• Isotope
• Radioactive decay
• None of these

The original element that undergoes radioactive decay is known as the...

• daughter element
• half-life
• parent element
• carbon-14

According to the graph, what fraction of the original parent isotope still exists after 3 half lives?

• 0,5000 g
• 0,2500 g
• 0,1250 g
• 0.0625 g

Modern mammals was during this era:

• Cenozoic
• Mesozoic
• Paleozoic

Modern mammals was during this era:

• Cenozoic
• Mesozoic
• Paleozoic

Which is the correct order for the 3 eras on geologic time scale.  This order is from oldest to current.

• Paleozoic, Mesozoic, Cenozoic
• Mesozoic, Paleozoic, Cenozoic
• Cenozoic, Mesozoic, Paleozoic

Which of the following would be used to determine the absolute age of a fossil found in a layer of rock that dates 20,000 years old?

• Uranium-235
• Potassium-40
• Carbon-14
• All of these

Earth is a fiery ball of molten rock.  There is no air or life on Earth

• Precambrian Era
• Paleozoic Era
• Mesozoic Era
• Cenozoic Era