Module 17: Transform and Convergent Plate Boundaries

Continental Arc

Line of volcanoes on a continental plate; the volcanoes are on a continent above a subducting oceanic plate.

Ocean to Continent Convergent Boundary

Oceanic plate subducts beneath the continental plate. A mountain range is produced parallel to the deep-sea trench. Earthquakes are produced along the subduction zone and volcanoes appear in the mountain belt behind the trench

The Himalayas

The world's highest mountain range, forming the northern border of the Indian subcontinent. They were formed when two continent to continent plates coverged.

Continent to Continent Convergent Boundaries

Two continental plates of equal density collide forming mountain ranges. When continental material collides it is forced upwards. When this happnes the crust is too thick for magma to get through so no volcanoes form. Metamorphic rocks are common because of the enormous pressure.

Continental Margin

a boundary between continental crust and oceanic crust

Ocean Trench

a long, narrow, deep depression in the ocean floor, typically one running parallel to a plate boundary and marking a subduction zone.

Convergent Plate Boundary

A tectonic plate boundary where two plates collide, come together, or crash into each other.

Transform Plate Boundaries

Areas where two plates grind past each other resulting in faults such as the San Andreas Fault. Massive earthquakes often occur at fault lines. Crust is neither created nor destroyed. They are sometimes called conservative plate boundaries because they do not create nor destroy lithosphere.

Appalachian Mountains

Formed from a continent-continent convergent plate boundary and resulted from acncient convergence when Pangaea came together.

Transform Faults

where tectonic plates slide horizontally past each other, they often cause offset spreading and can cut across continents. They have strike-slip movement and end at the junction of another fault type.

How Volcanic Arcs are Made:

1. Two oceanic plates converge. 2. The older denser plate dubducts into a trench. 3. The subducting plate causes melting in the mantle above it. 4. The magma finds a crack in the crust and fills a magma chamber beneath a volcano.

Active Margin

A continental margin that is colliding with another plate and as a result is geologically active; there are volcanoes and earthquakes present.

Volcanic Arc Islands

A line of volcanoes in the ocean that form islands and is the result of ocean-ocean plate convergence. Examples of Volcanic Arcs are The Philippines, The Aleutians, and Japan.

San Andreas Fault

A major geological fault in California formed by a sliding transform boundary. It is often considered the world's most famous transform fault.

Passive Margin

A margin that does not meet another plate and has no geological activity. Mountain ranges that formed in the geological past, but have not entirely eroded away are found at passive margins.

Subduction Zone

in convergent tectonic plates, the site at which an oceanic plate is sliding under a continental plate.