pluton

n.
A body of igneous rock formed beneath the surface of the earth by consolidation of magma.

[German, back-formation from plutonisch, plutonic, from Latin Plūtō, Plūtōn-, Pluto. See Pluto.]

What's a pluton? It depends whom you ask. Astronomers have a brand-new definition for pluton, but geologists say they're stealing the word:

"Plutons, under the first IAU draft definition, would be round astronomical objects that take more than two centuries to orbit the Sun. That, broadly speaking, includes most objects in the Kuiper belt, a ring of large debris beyond the orbit of Neptune.
"But a pluton in geology is a large bubble of molten rock that solidifies underground.... Yosemite National Park's Half Dome, in California, is a pluton that became exposed after it formed beneath the Earth."

Link: Plutons, planets and dwarves: Geologists and astronomers wrangle over words

Posted August 23, 2006.

See our Word Overheard blog to see interesting uses of strange words.

A solid rock body that formed by cooling and crystallization of molten rock (magma) within the Earth. Most plutons, or plutonic bodies, are regarded as the product of crystallization of magma intruded into surrounding “country rocks” within the Earth (principally within the crust). Igneous rock bodies are referred to generally as either extrusive or volcanic on one hand, or as intrusive or plutonic on the other, although the term volcanic is sometimes also used to refer to small, shallow intrusive bodies associated with volcanoes. See also Igneous rocks; Magma.

Plutons occur in a nearly infinite variety of shapes and sizes, so that definition of types is arbitrary in many cases. In general, two modes of emplacement can be recognized with regard to the country rock. Concordant plutons are intruded between layers of stratified rock, whereas the more common discordant plutons are characterized by boundaries that cut across preexisting structures or layers in the country rock. The principal types of concordant plutons are sills, laccoliths, and lopoliths; the principal types of discordant plutons are dikes, volcanic necks or plugs, stocks, and batholiths.

Several mechanisms of magma intrusion are known or proposed. The most simple ones, pertaining to smaller plutonic bodies, are forceful injection or passive migration into fractures. Larger plutons may form by several processes. For example, less dense magma may migrate upward along a myriad of channelways to accumulate as a large molten body within the upper crust. Further migration could occur by forceful injection, by stoping (a process where the magma rises as blocks of the roof of the magma chamber break off and sink), and by diapiric rise, where country rocks flow around the upward-moving magma body. See also Petrology.

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Dansk (Danish)
n. - pluton

Nederlands (Dutch)
gestolde rots diep onder de aardkorst

Français (French)
n. - pluton

Deutsch (German)
n. - Pluton, plutonischer Gesteinskörper

Ελληνική (Greek)
n. - πλουτωνίτης

Italiano (Italian)
plutone

Português (Portuguese)
n. - rocha (f) ígnea intrusiva (Miner.)

Русский (Russian)
интрузия изверженных горных пород

Español (Spanish)
n. - formación de roca plutónica

Svenska (Swedish)
n. - vulkanisk bergmassa

中文（简体）(Chinese (Simplified))
深层岩体

中文（繁體）(Chinese (Traditional))
n. - 深層岩體

한국어 (Korean)
n. - 마그마에 의한 심성암체

日本語 (Japanese)
n. - プルトン

العربيه (Arabic)
‏(الاسم) طبقه صخريه تصلبت تحت سطح الأرض‏

עברית (Hebrew)
n. - ‮גוש סלע וולקני שנוצר מתחת לפני הקרקע (גאולוגיה)‬

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