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An ultramafic rock in the precambrian of eastern Sinai
Geological Magazine, 1978SummaryTwo small outcrops of harzburgite and asbestos-bearing serpentinite, occurring S of Di Zahav in eastern Sinai are the first record of ultramafic rocks from the Sinai Precambrian massif.
M. Beyth, H. Grunhagen, A. Zilberfarb
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On the Origin of Ultramafic Rocks
Geological Society of America Bulletin, 1971It is argued that most alpine ultramafic bodies originated as cumulates in basic magma chambers high in the crust. From some of these chambers, magmas were intruded upward or extruded, leaving sill-like ultramafites behind. These were subsequently folded or dismembered by faulting, and, because of their high density, subsided during tectonism, to form ...
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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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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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