Sea Floor Spreading and Plate Tectonics

___________ is the process by which

new oceanic lithosphere (sea floor) forms as magma rises to Earth’s surface and solidifies at a mid-ocean ridge.

• Continental drift

• Sea-floor spreading

• Plate tectonics

• Mid-ocean range

Oceanic crust near the mid-ocean ridge is younger than oceanic crust farther away from the ridge.

• true

• false

Tags

NGSS.MS-ESS1-4

In sea-floor spreading, molten material rises from the mantle and erupts

• along the edges of all the continents

• along mid-ocean ridges

• in deep-ocean trenches

• at the north and south poles

Tags

NGSS.MS-ESS2-2

NGSS.MS-ESS2-3

_______

are mountain chains on the ocean floor.

• Sea-floor ridges

• Mid-ocean ridges

• Tectonic plates

• Photosynthesis

Tags

NGSS.MS-ESS2-3

Below is a picture of sea-floor spreading. How are the ocean crusts moving?

• Converging

• Diverging

• Sliding

• No movement

Tags

NGSS.MS-ESS2-1

Mid-ocean ridges are the sites of intense _________ activity.

• emotional

• volcanic

• earthquake

• mathematical

At a mid-ocean ridge, melted rock rises through cracks in the _________.

• ceiling

• river

• inner core

• sea floor

Tags

NGSS.MS-ESS2-2

In the 1960s, scientists studying the ocean floor discovered _____________.

• that the ocean floor had magnetic patterns

• the Titanic

• that the ocean floor had magical properties

• that the ocean floor was as smooth as a desert

Tags

NGSS.MS-ESS2-2

NGSS.MS-ESS2-3

What technology did scientists use in the mid-1900s to map the mid-ocean ridge?

• satellites

• deep-sea diving

• submarines

• sonar

Old oceanic crust is more dense than new oceanic crust because it is _______________.

• hot

• moving toward a deep-ocean trench

• cool

• closer to the mid-ocean ridge