blueschist

American  

[bloo-shist] / ˈbluˌʃɪst /

noun

1. blue schist.

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blueschist Scientific  

/ blo̅o̅′shĭst′ /

1. A bluish schist that gets its color from the presence of a sodic amphibolite, glaucophane, or a variety of glaucophane called crossite. Blueschist forms under conditions of high pressure but low temperature, as at the boundaries of converging tectonic plates.

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Example Sentences

As evidence of the youthfulness of the plate regimen, Dr. Stern points to two classes of rocks: ophiolites and blueschist.

From New York Times • Dec. 18, 2018

The California Coast Range near San Francisco has blueschist-facies rocks created by subduction-zone metamorphism, which include rocks made of blueschist, greenstone, and red chert.

From Textbooks • Jan. 1, 2017

In only a few places in the world, where the subduction process has been interrupted by some tectonic process, has partially subducted blueschist rock returned to the surface.

From Textbooks • Jan. 1, 2015

Most blueschist forms in subduction zones, continues to be subducted, turns into eclogite at about 35 km depth, and then eventually sinks deep into the mantle — never to be seen again.

From Textbooks • Jan. 1, 2015

“Revised ages of blueschist metamorphism and the youngest pre-thrusting rocks in the San Juan Islands, Washington.”

From Scientific American • Mar. 7, 2012