Exam 3: The Sea Floor

Atolls are circles of reefs that rim lagoons.

Many guyots and seamounts are aligned in chains (for example the Hawaiian Islands and Emperor seamounts)that form major _____.

Guyots and seamounts are scattered randomly on the sea floor.

A(n)_____ is a great mass of sediment-laden water that is pulled downward by gravity along the continental slope.

Turbidity currents flow down the continental slope until they come to rest on ___.

A basic tool for indirectly studying the sea floor is the ____,which measures water depth.

The _____ crust of the sea floor is covered in many places with layers of sediment.

All rocks and sediments of the sea floor are more than 3 billion years old.

Oceans cover more than 71% of the Earth's surface.

Seismic surveys of the sea have shown the oceanic crust to be divided into _______ major layers.

_____ parallel the shore,but are separated from it by wide,deep lagoons.

In a passive continental margin,there is a lack of _______.

The Grand Banks cable breaks of 1929 are interpreted to be the result of earthquake-caused ____.

Terrigineous sediment is sediment derived from the land.

A rift valley runs down the crest of most mid-oceanic ridges.

The deepest places on Earth,more than 11 km below sea level,are the abyssal plains.

__________ is the name applied to hot springs on the seafloor where 350 degree Celsius metal-rich solutions are discharged into the cold waters of the ocean.

Thick deposits of sediment called _____ are found at the base of many submarine canyons.

Earthquakes,volcanoes,Benioff seismic zones,and island arcs are all associated with this sea floor feature.

_____ are rounded masses of rock that form when molten lava erupts into cold water.