Plate Tectonics

The movement of the tectonic plates is caused by

• the rotation of the Earth.

• convection currents in the Asthenosphere

• the gravity of the iron-nickel core.

• the Moho discontinuity.

In some areas of the world, like California and Japan, earthquakes are a common occurrence. How can this best be explained?

• The strong ocean currents are undermining both areas causing earthquakes.

• Both areas are located near the edge of the Pacific Ocean, the unstable sand causes earthquakes.

• Both areas are subjected to strong ocean wind and waves that causes earthquakes.

• Both areas are on the boundary of active plates, the motion of the plates causes earthquakes.

Subduction zones occur on Earth where dense oceanic crust dives under more buoyant continental crust. These boundaries are characterized by a deep ocean trench next to a high continental mountain range, large numbers of earthquakes and volcanoes. All of this is further evidence for the

• big bang theory.
• theory of plate tectonics.
• origin of the species.
• theory of natural selection.
  

There are three types of plate boundaries. Which choice is NOT a type of plate boundary?

• convergent
• thrust
• divergent
• transform

Observe this diagram of a plate boundary. One statement BEST describes what is happening. It is that

• the oceanic crust is melting.

• the denser ceanic crust is subducting under the less dense oceanic crust

• volcanic islands are forming.

• the tectonic plates are moving away from each other.

The map in the picture shows tectonic plate boundaries. This map would be useful in predicting the location of future

• droughts

• hurricanes

• earthquakes

• tornadoes

What geological forces might be responsible for this range of mountains?

• diverging tectonic plates
• erosion of the land by the ocean
• converging tectonic plates
• deposition of sediments by the ocean
  

Earthquake epicenters (center of where the earthquakes started) were mapped for a 35 year period in the diagram above. The black dots indicate these epicenters. The black dots appear along what feature on Earth?

• hot spots

• plate boundaries

• rift zones

• sea floor spreading

The Earth’s surface is not a solid surface but is divided into

• several oceanic plates.
• continental and crustal plates.
  
• seven continental plates.
• continental and oceanic plates.
  

Geologists have long recognized that earthquakes are not randomly distributed on Earth but occur in concentrated areas that coincide with __________ and provide evidence for the theory of ___________ .

• mountain ranges; fault zones.
• continental borders; supercontinents.
• plate boundaries; plate tectonics
• areas of liquid magma; sea floor spreading.