What happens when a plate carrying oceanic crust collides with a plate carrying continental crust?

When two oceanic plates collide, the younger of the two
plates, because it is less dense,* will ride over the edge of the older plate. *[Oceanic
plates grow more dense as they cool and move further away from the Mid-Ocean Ridge].
(Image: Keith-Wiess Geological Laboratories; Rice
University)

The older, heavier
plate bends and plunges steeply through the athenosphere, and descending into the earth,
it forms a trench that can be as much as 70 miles wide, more than a thousand miles long,
and several miles deep. The Marianas Trench, where the enormous Pacific Plate is
descending under the leading edge of the Eurasian Plate, is the deepest sea floor in the
world. It curves northward from near the island of Guam and its bottom lies close to
36,000 feet below the surface of the Pacific Ocean.

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