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Lamprophyres of Italy: early Cretaceous alkaline lamprophyres of Southern Tuscany, Italy
Lithos, 2014Abstract Alkaline lamprophyres from southern Tuscany are early Cretaceous, ultrabasic, primary mantle melts that have not undergone significant magmatic differentiation. New mineralogical, geochemical and Sr, Pb and Nd isotopic evidence shows contrasting geochemistries with “crustal-like” and mantle geochemical features.
STOPPA, Francesco +4 more
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Eos, Transactions American Geophysical Union, 1936
Abstract—A preliminary suggestion that lamprophyres may be of hydrothermal origin.
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Abstract—A preliminary suggestion that lamprophyres may be of hydrothermal origin.
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Geological Magazine, 1946
Judd was one of the early workers to recognize that changes in the mineral constitution of an intrusive igneous rock, changes affecting the earlier minerals, may take place prior to the completion of crystallization. He points out that minerals, since their first crystallization, may have undergone several series of changes, totally dissimilar in kind,
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Judd was one of the early workers to recognize that changes in the mineral constitution of an intrusive igneous rock, changes affecting the earlier minerals, may take place prior to the completion of crystallization. He points out that minerals, since their first crystallization, may have undergone several series of changes, totally dissimilar in kind,
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Lamprophyres and carbonatitic lamprophyres related to rifting in the Labrador Sea
Lithos, 1980Abstract Lamprophyre dykes intruded into the Archaean of South West Greenland are believed to coincide with the early stages of rifting in the Labrador Sea area. They yield K/Ar and fission-track ages of 150–115 m.y. which are similar to the apatite fission-track ages from the host rocks but which predate the formation of ocean floor.
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Mineralogy and Petrology, 1994
Lamprophyres are a polygenetic group of rocks that have formed by the crystallization of common magma types, including lamproites and kimberlites, under volatile-rich conditions. The term lamprophyre is considered to have no genetic significance and the recognition of a lamprophyre facies is proposed as a means of conveying the concept that some ...
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Lamprophyres are a polygenetic group of rocks that have formed by the crystallization of common magma types, including lamproites and kimberlites, under volatile-rich conditions. The term lamprophyre is considered to have no genetic significance and the recognition of a lamprophyre facies is proposed as a means of conveying the concept that some ...
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Emplacement features of lamprophyre and carbonatitic lamprophyre dykes at Aillik Bay, Labrador
Geological Magazine, 1989AbstractAlkaline and ultramafic lamprophyre dykes at Aillik Bay on the coast of central Labrador exhibit features indicative of volatile-rich conditions at the time of emplacement. Aillikites (ultramafic lamprophyres) are flanked by closely spaced fracture systems whose formation was promoted by a carbonate-rich fluid moving ahead of the intruding ...
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Plutonic and Volcanic Equivalents of Lamprophyres
1991As already shown (Section 3.1), lamprophyres are overwhelmingly hypabyssal, mediumgrained intrusions. Although LL commonly exist as volcanic rocks, and AL and CAL do so rarely, KlL and UML almost never do (Section 3.1.7). Again, although relatively coarsegrained (e.g. pegmatoidal) segregations do exist in some dykes (e.g.
A. E. Wright, D. R. Bowes
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The Mica-Lamprophyres of Wigtownshire
Geological Magazine, 1926The Geological Survey has recently formed a very extensive collection of the dyke-rocks of Galloway. This collection was made mainly by Mr. Robert Eckford, and, to a less extent, by Mr. Wm. Manson. One or more specimens were taken of practically every dyke shown on the original 6-inch field-maps. Since there are over 500 collected dykes in Wigtownshire
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Nomenclature and Relations of the Lamprophyres
Geological Magazine, 1923The alnoites form one of the rarest groups of dike rocks. Owing to their restricted distribution, they have remained comparatively little known, outside of the original alnoite of Alnö I., and a few North American occurrences, until the last few years. Recently, owing to discoveries in Canada (near Montreal), and near the Bohemian Mittelgebirge (in the
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Gold, Lamprophyres, and Porphyries
1989Abstract Extremely intimate space-time associations between caic-alkaline (shoshonitic) lamprophyres and mesothermal gold deposits are now confirmed worldwide and from Archean to Tertiary times. They include the late Archean gold deposits of the Superior province (Canada) and the Norseman-Wiluna belt (Western Australia), which hosts ...
Rock, Nicholas M. S. +3 more
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