earth science exam 1

Which of the following best explains how a tephra deposit forms?

Airborne ash and rocks from a volcanic eruption remain suspended in the air for a long time before eventually settling to the ground in a new location far from the volcano.

In which layer does mantle convection occur?

Asthenosphere

How are sills and lapoliths similar?

Both form from magma that flows horizontally.

Which force from the asthenosphere is responsible for isostatic uplift?

Buoyancy

Which type of volcano is formed from alternating layers of lava and ash?

Composite volcano

Which type of stress is shown in the image?

Compression stress

Which force is responsible for pulling a plate downward into the asthenosphere?

Gravity

What is typically responsible for forming volcanic island chains in the oceans?

Hot spot volcanism

Mafic lava tends to have low silica content. Based on this, which of the following statements about mafic lava is most likely true?

It contains fewer volatile gases.

What phenomenon is responsible for hot spot volcanism?

Mantle plumes

The theory of plate tectonics suggests that about 200 million years ago, all of Earth's land was confined to a single continent called

Pangaea.

Which natural process is responsible for ridge push?

Seafloor spreading

Which type of stress is shown in the image?

Shear stress

Which type of volcano has gentle slopes and forms at a divergent plate boundary?

Shield volcano

Which of the following must be balanced for a portion of the lithosphere to reach isostatic equilibrium?

The buoyant force from the asthenosphere and gravity

When two plates form a subduction zone, which plate will subduct?

The denser plate

Earth's crust is part of which of Earth's layers?

The lithosphere

Which process is used to locate the epicenter of an earthquake?

Triangulation

What can cause the eruption from a shield volcano to become explosive?

Water accumulated in the vent

An enormous wave generated by an earthquake beneath the seafloor is known as a

tsunami.