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Transtension and alkaline magmatism of the Romanche Fracture Zone
Geotectonics, 2008New magnetometric, petrological, and geochemical data on basalts from the central Romanche Fracture Zone (FZ) allow us to classify these rocks into two groups. The igneous rocks from the active part of the fracture zone that experienced transtension are referred to as alkaline rocks.
A. A. Bulychev +4 more
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Alkaline magmatism and uplift of continental crust
Proceedings of the Geologists' Association, 1980Doming associated with alkaline magmatism can be developed in East Africa and elsewhere on three quite different scales; lithospheric, crustal and sub-volcanic. Each is considered to be the result of separate mantle and crustal processes, and require distinction. Lithospheric domes, e.g. the East African Dome, are seen as extensive areas of continental
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Neoproterozoic alkaline magmatism at Sivamalai, southern India
Gondwana Research, 2006Abstract The Sivamalai alkaline complex lies at the southern margin of the Cauvery Shear System that separates the Archaean and Proterozoic domains of the Southern Granulite Terrain in India. U–Pb TIMS dating of zircon from a pegmatitic syenite sample in the complex yields a concordant age of 590.2 ± 1.3 (2σ) Ma which is interpreted to date the ...
Jean-Louis Paquette +4 more
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Mesozoic mafic alkaline magmatism of southern Scandinavia
Contributions to Mineralogy and Petrology, 2004More than 100 volcanic necks in central Scania (southern Sweden) are the product of Jurassic continental rift-related mafic alkaline magmatism at the southwest margin of the Baltic Shield. They are mainly basanites, with rarer melanephelinites. Both rock groups display overlapping primitive Mg-numbers, Cr and Ni contents, steep chondrite-normalized ...
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Contributions to Mineralogy and Petrology, 1990
The polyphasal magmatic evolution of the Caledonian Karmoy Ophiolite Complex includes: (1) formation of an axis sequence from island-arc tholeiitic (IAT) and more MORB-like magmas (493+7/-4 Ma); (2) intrusion of magmas of boninitic affinity (485±2 Ma); (3) intrusion of MORB- and IAT-like magmas; (4) intrusion and extrusion of calc-alkaline magmas (470 ...
Pedersen, R. B., Hertogen, J.
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The polyphasal magmatic evolution of the Caledonian Karmoy Ophiolite Complex includes: (1) formation of an axis sequence from island-arc tholeiitic (IAT) and more MORB-like magmas (493+7/-4 Ma); (2) intrusion of magmas of boninitic affinity (485±2 Ma); (3) intrusion of MORB- and IAT-like magmas; (4) intrusion and extrusion of calc-alkaline magmas (470 ...
Pedersen, R. B., Hertogen, J.
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Kimberlites and Associated Alkaline Magmatism
1982The substantial contribution of the alkaline igneous rocks to the South African economy is well known and far exceeds their abundance in the geologic record. Most notable are the diamondiferous kimberlites and the rocks of the Palabora Intrusive Suite containing copper, iron, phosphate, uranium, and vermiculite. Kimberlites are also significant because
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Microcomponents as indicators of the differentiation of alkaline magmatic series
Physics and Chemistry of the Earth, 1979Abstract The distinction of two types of differentiation of alkaline magmatic series (1 related to the evolution of alkaline basaltic magma and 2 strongly undersaturated with silica, ultrabasic alkaline) is confirmed by the distribution of trace elements.
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Tertiary alkaline magmatism in Trans-Pecos Texas
Geological Society, London, Special Publications, 1987Summary Alkaline magmatism in far W Texas extended from 48 to 16 Ma ago, peaking in volume during the interval 37-26 Ma when all the felsic rocks were emplaced. Primitive magmas are rare, if not entirely lacking, but ne- and {ol+hy}-normative hawaiite and mugearite liquids (Ni <120 ppm; 100Mg/(Mg+Fe)<
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Paleomagnetism of the Cretaceous Alkaline Magmatism of the Lusitanian Basin, Portugal
2021<p>The paleogeographic reconstructions of the Iberian plate during the opening of the Atlantic Ocean is still poorly constrained. Major limitations include the paucity of high quality paleomagnetic poles and geochronological constrains, the occurrence of widespread remagnetization events, and controversial seafloor magnetic anomalies ...
Rafael Dinis +6 more
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Petrology, 2017
This paper focuses on the occurrences of tholeiitic magmatism in the northeastern Fennoscandian shield. It was found that numerous dolerite dikes of the Pechenga, Barents Sea, and Eastern Kola swarms were formed 380–390 Ma ago, i.e., directly before the main stage of the Paleozoic alkaline magmatism of the Kola province.
D. S. Yudin +8 more
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This paper focuses on the occurrences of tholeiitic magmatism in the northeastern Fennoscandian shield. It was found that numerous dolerite dikes of the Pechenga, Barents Sea, and Eastern Kola swarms were formed 380–390 Ma ago, i.e., directly before the main stage of the Paleozoic alkaline magmatism of the Kola province.
D. S. Yudin +8 more
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