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The origin of ultramafic and ultrabasic rocks
Tectonophysics, 1969Ultramafic rocks are classified in terms of their field associations and tectonic environment. Eleven associations are distinguished, some with subdivisions. The major features of each association are described in turn, and it is emphasized that the variety of field and petrographic associations indicates that a variety of processes is involved in the ...
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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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Mineral Carbonation in Ultramafic and Basaltic Rocks
2016Carbon capture and storage in the form of mineral carbonation in ultramafic and basaltic rocks offers a geologically stable repository of anthropogenic CO2. This chapter provides fundamental, theoretical and applied concepts relevant to mineral carbonation in peridotite, serpentinite and basaltic rocks.
Pablo García del Real, V. Vishal
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Chlorine and fluorine abundances in ultramafic rocks
Geochimica et Cosmochimica Acta, 1968Abstract A total of 55 ultramafic rocks of various modes of occurrence has been analysed for chlorine and fluorine by a rapid spectrophotometric method. The different modes of occurrence seem to have different abundance levels of Cl and F, but this may be due to secondary effects.
A.M. Stueber, W.H. Huang, W.D. Johns
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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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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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Metasomatic Alteration of Ultramafic Rocks
1989Metasomatized ultramafic rocks from the 3800 Ma Isua supracrustal belt have been preferentially enriched in calcium, aluminium and silica, but show no or only little addition of potassium and rubidium. This unusual geochemical response to fluid infiltration can be explained in the light of a low buffered activity of aqueous silica during progressive ...
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Peridotites and other ultramafic rocks
Geology TodayPeridotites are a group within the category of ultramafic rocks. These are usually dark‐coloured rocks rich in magnesium, poor in silica and lacking feldspars. Earth's mantle, which makes up 83 percent by volume and 67 percent by weight of the planet, consists largely of peridotite, which, although relatively sparse at the surface, therefore, is Earth ...
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Tectonophysics, 1969
Abstract A subdivision of the orogenic peridotites into ophiolitic (or truly Alpine-type) and “root-zone” peridotites is proposed, and their differences in tectonic setting and metamorphic facies are discussed. Some current hypotheses for the origin and mode of emplacement of the orogenic peridotites are briefly reviewed.
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Abstract A subdivision of the orogenic peridotites into ophiolitic (or truly Alpine-type) and “root-zone” peridotites is proposed, and their differences in tectonic setting and metamorphic facies are discussed. Some current hypotheses for the origin and mode of emplacement of the orogenic peridotites are briefly reviewed.
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