oceanic crust: Quick Facts

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Photos and Videos

Cross-sectional diagram of Earth's outer layers, showing oceanic and continental crust at the surface, the rigid lithosphere, the partially melted asthenosphere, and transitions from upper to lower mantle, with labeled depths and rock properties.

Crew members aboard a drilling ship inspecting a rock core during a scientific expedition that succeeded for the first time in drilling through the upper oceanic crust.

Cross-sectional diagram illustrating plate tectonics, showing oceanic and continental crust moving over the asthenosphere. It highlights divergent boundaries at oceanic ridges where crust forms, convergent boundaries at trenches with subduction zones where crust is destroyed, and a transform boundary with a fault. Features such as island arcs, rising magma, and hotspots are labeled.

A world map uses color bands to show the age of Earth's oceanic crust in millions of years, with red marking the youngest crust along mid-ocean ridges and blue representing the oldest crust farther from spreading centers.

Diagram showing seafloor spreading at a midocean ridge, with arrows indicating tectonic plates moving apart. Magma rises to form new seafloor, and bands of normal and reversed magnetic polarity are labeled on either side of the ridge.

cross section of a tectonic plate

How does plate tectonics change Earth's surface?

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