KREEP

KREEP
KREEP [krēp]
n.
〚K (symbol for potassium) + r(are-)e(arth) e(lements) + p(hosphorus)〛
a type of basaltic lunar rock rich in potassium, phosphorus, etc.

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▪ rock
      a suite of lunar lavas, relatively enriched in certain elements, that were identified in the analysis of rock samples that Apollo (Apollo program) astronauts brought back from the Moon. The elements include potassium (chemical symbol K), rare-earth elements, and phosphorus (P), from which the acronym KREEP is derived. Lunar scientists have interpreted the enrichment to be a signature of the cooling history of lunar rocks from an ancient magma ocean more than four billion years ago. The elements are called incompatible because they do not fit well into the crystal lattices of the most common lunar minerals such as pyroxene, olivine, and plagioclase, which crystallized relatively early from the magma ocean. Being preferentially excluded, the incompatable elements thus became part of the last liquids to solidify.

      Because the incompatible elements also include radioactive ones such as thorium, which spontaneously emits gamma rays, it is possible to map the distribution of KREEP by using gamma-ray spectrometry from spacecraft in lunar orbit. Lunar Prospector, which orbited the Moon in 1998–99, provided the first such map of the entire lunar surface. The data revealed chemical variations that, when correlated with other remote-sensing data, enabled scientists to develop models of regional differences in the evolution of lunar landforms and in the Moon's thermal and mineral history.

James D. Burke
 

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Universalium. 2010.

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Look at other dictionaries:

  • KREEP — ist ein magmatisches Gestein, das auf dem Mond vorkommt. Insbesondere wurde es in Form von Impaktbrekzien in Kratern oder neben Basalten (vgl. auch Lunabas und Lunarit) gefunden. Hervorzuheben ist seine chemische Zusammensetzung aus sogenannten… …   Deutsch Wikipedia

  • KREEP — KREEP, an acronym built from the letters K (the atomic symbol for the element potassium), REE (Rare Earth Elements) and P (for phosphorus), is a geochemical component of some lunar impact melt breccia and basalt rocks. Its most significant… …   Wikipedia

  • KREEP — es una sigla utilizada para nombrar un tipo de suelo lunar. Cada letra hace referencia a la composición química, así la K es el potasio, y la P corresponde al fósforo. RRE viene del inglés Rare Earth Elements, que quiere decir Elementos Raros de… …   Enciclopedia Universal

  • kreep — [kʀip] n. m. ÉTYM. 1972; mot angl., 1971; de K, symbole du potassium, angl. Rare Earth Element « terre rare », et P, symbole du phosphore. ❖ ♦ Anglic. Substance trouvée sur la Lune, qui contient de grandes quantités de potassium, de phosphore et… …   Encyclopédie Universelle

  • KREEP — [krēp] n. [K (symbol for potassium) + r(are )e(arth) e(lements) + p(hosphorus)] a type of basaltic lunar rock rich in potassium, phosphorus, etc …   English World dictionary

  • KREEP — Se llama KREEP a un tipo de suelo lunar; esta designación proviene de los componentes del mismo: potasio (K), tierras raras (REE, del inglés: Rare earth elements) y fósforo (P). Actualmente se cree que el KREEP representa los últimos restos de la …   Wikipedia Español

  • KREEP — Kalium Rare Erd Elements & Phosphor Bez. f. Teile des Mondgestein, entdeckt durch Apollo 12 …   Acronyms

  • KREEP — Kalium Rare Erd Elements & Phosphor Bez. f. Teile des Mondgestein, entdeckt durch Apollo 12 …   Acronyms von A bis Z

  • KREEP — Potassium, Rare Earth Elements and Phosphorus (Moon Rocks & Soil) Contributor: CASI …   NASA Acronyms

  • KREEP — ˈkrēp noun Etymology: K (potassium) + Rare Englisharth Englishlement + P (phosphorus) : a type of rock found especially on the moon that contains potassium, rare earth elements, and …   Useful english dictionary

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