Which of these statements correctly describe Asthenosphere?

• Soft, weak upper portion of the mantle where the lithospheric plates float and move around

• The topmost, solid part of the Earth that is composed of several plates

• The boundary that separates the crust and the mantle

• The process in which the crust plunges back into the Earth

It is the rigid outermost shell of the Earth which is composed of the crust and the top part of the upper mantle

• Convergent plate

• Oceanic plate

• Lithosphere

• Continental plate

Which of the following statements correctly describe continental crust?

• It is less dense than oceanic crust

• It is thicker than oceanic crust

• It is thin and denser than oceanic crust

• Both A and B

The lithospheric plates are of two types. Which is the thickest type?

• Oceanic plate

• Continental plate

• Convergent plate

• Divergent plate

How are oceanic crust being formed?

• By freezing of the mantle

• By partial melting of the mantle at mid-ocean ridges

• By movement of plates

• By destroying the crust

Which type of seismic waves are the slowest?

• S-waves

• P-waves

• Surface waves

• Body waves

What is the name of the waves given off by an earthquake?

• Seismic Waves

• Radiation waves

• Sound waves

• Compaction waves

An instrument that detects and measures earthquakes is a

• Seismogram

• Focus seismic map

• Focus

• Seismograph

Which is the first seismic wave to arrive at a seismograph station (where they are measured and detected)?

• L-wave

• R-wave

• P-wave

• S-wave

How many seismograph stations are needed to locate the epicenter of an earthquake?

• 1

• 2

• 3

• 4