Is plagioclase removal responsible for the negative Eu anomaly in the source regions of mare basalts

Journal Article · Thu Nov 30 23:00:00 EST 1989 · Geochimica et Cosmochimica Acta; (USA)

DOI:https://doi.org/10.1016/0016-7037(89)90113-0· OSTI ID:7060969

Shearer, C K; Papike, J J ^[1]

---

1. South Dakota School of Mines and Technology, Rapid City (USA)

The nearly ubiquitous presence of a negative Eu anomaly in the mare basalts has been suggested to indicate prior separation and flotation of plagioclase from the basalt source region during its crystallization from a lunar magma ocean (LMO). Are there any mare basalts derived from a mantle source which did not experience prior plagioclase separation Crystal chemical rationale for REE substitution in pyroxene suggests that the combination of REE size and charge, M2 site characteristics of pyroxene, fO{sub 2}, magma chemistry, and temperature may account for the negative Eu anomaly in the source region of some types of primitive, low TiO{sub 2} mare basalts. This origin for the negative Eu anomaly does not preclude the possibility of the LMO as many mare basalts still require prior plagioclase crystallization and separation and/or hybridization involving a KREEP component.

• OSTI ID: 7060969
• Journal Information: Geochimica et Cosmochimica Acta; (USA), Journal Name: Geochimica et Cosmochimica Acta; (USA) Vol. 53:12; ISSN GCACA; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
640106 -- Astrophysics & Cosmology-- Cosmology
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BASALT
CRYSTALLIZATION
ELEMENTS
FELDSPARS
GEOLOGIC HISTORY
GEOLOGY
IGNEOUS ROCKS
LUNAR MATERIALS
MAGMA
MAGMATISM
MATERIALS
METALS
MINERALS
MOON
OXYGEN COMPOUNDS
PETROCHEMISTRY
PETROGENESIS
PHASE TRANSFORMATIONS
PYROXENES
RARE EARTHS
ROCKS
SATELLITES
SEPARATION PROCESSES
SILICATES
SILICON COMPOUNDS
VOLCANIC ROCKS