Earth Semester Final

Which of the following would be an example of evidence that could be used to construct the geologic time scale?

• a geologic event observed in different rock sequences around the world

• index fossils

• radiometric dating of rocks in an impact crater

• all of the above

Which of the following has the strongest effect on the uneven distribution of thermal energy in the atmosphere?

• the Coriolis effect

• the differences in ground cover

• the curvature of Earth’s surface

• the distribution of land and water

The most abundant gas in Earth's atmosphere is

• carbon dioxide

• hydrogen

• nitrogen

• oxygen

Earth's atmosphere is approximately

• 78% nitrogen and 21% oxygen

• 76% nitrogen and 24% oxygen

• 78% oxygen and 21% nitrogen

• 76% oxygen and 24% nitrogen

Using radiometric dating, the age of Earth has been established as about ________.

• 4000 years old

• 4 million years old

• 4. 4.6 Billion years old

• 13-15 billion years old

Why do scientists base their estimates of Earth's age on the radiometric dating of Earth rocks, lunar rocks, and meteorites?

• They think that all objects in the universe formed at the same time

• They think that Earth, the moon, and meteorites all came from the asteroid belt at about the same time

• They think that Earth's oldest rocks were ejected into space when Earth collided with large asteroids, and that some of these rocks landed on the Moon

• They think that the best age for Earth is determined by viewing Earth, the moon, and meteorites as part of the same evolving system

A half-life is:

• the amount of time it takes for half of a stable isotope to decay and form a radioactive isotope.

• the amount of time it takes for half of the neutrons of a radioactive isotope to decay and form protons.

• the amount of time it takes for 50 percent of the atoms of parent isotope sample to decay and form atoms of a daughter isotope.

• the amount of time it takes one atom of a parent isotope to halfway decay to form a daughter isotope.

A large earthquake happens at a fault beneath the ocean floor, causing a rupture in Earth's crust. Which answer describes the most likely result of the rupture?

• The crust will displace the ocean water above the rupture, resulting in a powerful, rapidly moving wave.

• Molten rock from Earth's interior will flow through the rupture and solidify when it enters the ocean, producing an underwater mountain.

• Molten rock from Earth's interior will flow through the rupture, reducing the temperature of the surrounding water and temporarily changing the directions of ocean currents.

• The ocean water over the rupture will pour through the opening in Earth's crust, cooling the mantle rock beneath the ocean and reducing the risk of future earthquakes.

If you are inside a building during an earthquake, which of the following locations is safest to move to?

• stairwell

• the center of an upstairs floor

• a load-bearing door frame

• a corner of the ground floor away from windows

How does an earthquake displace water in the ocean?

• When the ocean floor ruptures, it produces vibrations that impart motion to the overlying water.

• When the ocean floor ruptures, a portion of land moves upward, causing the water above the land to rise with it.

• both A and B

• neither A nor B