Which layer of Earth is the thinnest?

• Inner Core

• Crust

• Outer Core

• Mantle

Which layer of the earth has physical properties resulting from its dense, iron-rich composition?

• crust

• mantle

• core

• none of the choices

(a)   is/are piece(s) of the Earth's crust and uppermost mantle, together referred to as the lithosphere.

• Asthenosphere

• Boundary

• Plate

• Tectonic Plates

The plates of the lithosphere float on the (a)   .

• Asthenosphere
• Boundary

• Plate

• Tectonic Plates

A (a)   is where two or more of these tectonic plates come in contact.

• Asthenosphere

• Boundary

• Plate

• Tectonic Plates

tectonics is the theory that explains the formation and movement of the Earth's crust.

• Asthenosphere

• Boundary

• Plate

Los Angeles, CA was built where the edge of the Pacific plate is slipping:

• under the North American plate.

• over the North American plate.

• south along the North American plate.

• north along the North American plate.

Continental crust is found on top of oceanic crust because:

• oceanic crust is much thicker, so it must be on the bottom.

• oceanic crust is older, so it must be on the bottom.

• oceanic crust is denser, so it must be on the bottom.

• oceanic crust is made of mostly igneous rock, so it must be on the bottom.

A layer at the bottom of the chart is typically older in age than layers at the top.

• True

• False

In an area where a river has cut deep into Earth, there are several layers of very different rock exposed. The oldest rock layer is most likely to be the layer that is:

• below the other layers.

• the thickest layer.

• the most rich in fossils.

• igneous intrusive rock.