The features of active and passive continental margins and the characteristics of ocean basins are evidence for existence, or absence of a plate boundary. Read the sentences below, and fill in the blanks to make them complete and correct.
Match the words in the left column to the appropriate blanks in the sentences on the right. Make certain each sentence is complete before submitting your answer. Note that some terms will remain unused.
1. Oceanic crust spreads at , creating new crust and slowly enlarging the ocean basin.
MID OCEAN RIDGE
2. Submarine canyons are deep valleys at passive continental boundaries. They are likely carved out by turbidity currents, which occur when sediment-laden water rapidly moves down slope.
SUBMARINE CANYONS
3. Melt from the subducting plate rises to the surface, erupts through the crust on the overriding plate and forms continental volcanic arcs on continents, or volcanic island arcs in the ocean.
CONTINENTAL VOLCANIC ARCS
VOLCANIC ARCS
4. Subduction zones surrounding the Pacific Ocean give rise to volcanoes. This area surrounding the Pacific Ocean is called the Ring of Fire.
RING OF FIRE