Plate Tectonics Plate Boundaries

The movement of the tectonic plates is caused by

• the Moho discontinuity.
• the gravity of the iron-nickel core
• convection currents in Earth's mantle
• the rotation of the Earth.

In the diagram of the ocean basin, where is the oldest oceanic crust found?

• A
• B
• C
• D

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

• transform
• thrust
• divergent
• convergent

Different events on Earth are associated with different tectonic plate boundaries.Which events are associated with transform plate boundaries?

• volcanoes and sea floor spreading
• folded mountains
• trenches and island arcs
• faults and earthquakes

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

• this is typical of a subduction zone
•  the tectonic plates are moving away from each other.
• volcanic islands are forming
• the oceanic crust is melting.

The map shown would be useful in predicting the location of future

• tornadoes
• hurricanes
• earthquakes
• droughts

Fossils of a now extinct dinosaur have been found near the east coast of South America and the west coast of Africa. The dinosaur could not swim or fly. What does this suggest about the continents of South America and Africa?

• The continents were once connected.
• The same type of animals evolved on both continents.
• Prehistoric man transported the dinosaur between the continents.
• A land bridge once connected the continents.

Earthquake epicenters were mapped for a 35 year period in the diagram above. The black dots marking the epicenters also represent what feature on Earth?

•  hot spots
• rift zones
• plate boundaries
• sea floor spreading

1 - convection in the upper mantle magma 2 - injection at the spreading boundaries
3 - gravity pulling the plates downward at subduction zones
These are three theorized causes of

• changing of the climate.
• movement of the tectonic plates.
• glacial melting.
•  high and low ocean tides.

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

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