picrite

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picrite

(ˈpɪkraɪt)
n
(Geological Science) a coarse-grained ultrabasic igneous rock consisting of olivine and augite with small amounts of plagioclase feldspar
References in periodicals archive ?
'To our knowledge, the Luenha picrites are the first lava samples that could originate from the plume source that has been previously inferred from various geological and geophysical data on the Karoo province.
The petrogenesis of Gorgona komatiites, picrites and basalts: new field, petrographic and geochemical constraints.
The geochemistry and petrogenesis of the Late-Cretaceous picrites and basalts of Curacao, Netherlands Antilles: A remnant of an oceanic plateau.
These rocks were first interpreted as komatiites (Alvarado et al., 1997) and then as picrites resulting of accumulation processes (Hauff et al., 2000) because the textures are porphyritic rather than spinifex.
These rocks contain more than 18 wt% MgO (Le Bas 2000) and are distinguished from other magnesium-rich rocks, such as picrites and meimechites, by having spinifex texture (characterized by spectacular arrays of subparallel or randomly-oriented skeletal, platy and bladed olivine crystals set in a glassy groundmass; Fig.
However, the present exposures of picrites in the Deccan province are limited and their PGE contributions seem quite insufficient to approach the magnitude of the K-T Ir anolmaly (Sutherland, 1994).
Edwards Basalt Formation--which is in turn disconformably overlain by the Widgiemooltha Komatiite Formation (olivine peridotites to picrites).
Tournon (1984) reported for the same area an isolated block of picrite instead, and Calero (1987) reported in the Tortugal area a similar ultramafic rock but classified it as lamprophyre (monchiquite).