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Lichens and ultramafic rocks: a review
The Lichenologist, 2004Floristic, vegetational and ecological features of lichens in ultramafic environments are reviewed using a wide range of literature dating from the beginning of the 20th century. Co-presence of acidophytic (silicicolous) and basiphytic (calcicolous) species and the occurrence of species characterized by particular (disjunct) distribution patterns are ...
FAVERO LONGO, Sergio Enrico +2 more
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Geochimica et Cosmochimica Acta, 1953
Abstract Quantitative spectrochemical determinations of potassium in 50 specimens of ultramafic rock confirm the preliminary observation ( Ahrens , Pinson and Kearns , 1952) that the abundance of potassium in this rock type is much lower than has usually been assumed.
W Holyk, L.H Ahrens
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Abstract Quantitative spectrochemical determinations of potassium in 50 specimens of ultramafic rock confirm the preliminary observation ( Ahrens , Pinson and Kearns , 1952) that the abundance of potassium in this rock type is much lower than has usually been assumed.
W Holyk, L.H Ahrens
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Lunar Ultramafic Glasses, Chondrules and Rocks
Nature Physical Science, 1972Analysis of all samples returned by lunar missions before Apollo 15 has shown green glasses of ultramafic composition in soil and microbreccia samples. Ultramafic glasses in Apollos 11 and 14 and Luna 16 samples are rare and similar to each other in composition but different from any of the rocks collected at these sites.
T. E. BUNCH +4 more
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1972
The ultramafic rocks are composed mainly of dark-colored mafic or ferro-magnesian minerals such as olivine, pyroxene, amphibole, serpentine, garnet, biotite, and opaque oxides. They are usually, but not always, ultra-basic (having less than 45 percent SiO2).
Gunter Faure, James L. Powell
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The ultramafic rocks are composed mainly of dark-colored mafic or ferro-magnesian minerals such as olivine, pyroxene, amphibole, serpentine, garnet, biotite, and opaque oxides. They are usually, but not always, ultra-basic (having less than 45 percent SiO2).
Gunter Faure, James L. Powell
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Metamorphism of Ultramafic Rocks
1994Ultramafic rocks are magnesium silicate rocks that normally contain no felsic minerals or very little (
Kurt Bucher, Martin Frey
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Alkali content of alpine ultramafic rocks
Geochimica et Cosmochimica Acta, 1965The lower limit of abundance of sodium and potassium in ultramafic rocks is less than the threshold amount detectable by conventional analytical methods. By a dilutionaddition modification of the flame-spectrophotometric method, sodium and potassium have been determined in 40 specimens of alpine ultramafic rocks.
Warren Hamilton, Wayne Mountjoy
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Fossilized Life in Subseafloor Ultramafic Rocks
Geomicrobiology Journal, 2018Ultramafic rocks are hypothesized to support a subseafloor hydrogen-driven biosphere because of extensive production of bioavailable energy sources like H2 or CH4 from fluid-rock interactions.
M. Ivarsson +4 more
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Aragonite from deep sea ultramafic rocks
Geochimica et Cosmochimica Acta, 1980Abstract Aragonite mineralization was observed in serpentinized peridotites from the Romanche and Vema Fracture Zones in the Atlantic and the Owen Fracture Zone in the Indian Ocean, either in veins or as radial aggregates in cavities within the serpentinites. Evidence of incipient dissolution of the aragonite crystals was observed in one case.
E. Bonatti +3 more
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Geotectonic significance of ultramafic rocks
Earth-Science Reviews, 1973Abstract Ultramafic rocks can be divided into 5 principal geotectonic groups, as follows: (1) Layered gabbro-norite-peridotite masses, commonly associated with all ages of terrane, possibly connected with accretionary plate margins. (2) Concentrically zoned Alaska-type bodies, possibly associated with consuming plate margins. (3) Ultramafic lavas and
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Rare-Earth abundances in some ultramafic rocks
Journal of Geophysical Research, 1971A survey has been made of the abundances of the rare earths (REE) in ultramafic rocks. Samples analyzed were taken from alpine regions, layered intrusions, basaltic nodules, and kimberlite pipes. A wide range of REE concentrations and relative abundances was found.
Frederick A. Frey +2 more
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