Magma-mingling and melt modification between granitic pipes and host diorite, Guernsey, Channel Islands
Article Abstract:
The Guernsey Northern Igneous Complex contains 20-40 cm-diameter cylindrical pipes, formed by the intrusion of granite magma into the overlying diorite magma. Physical mixing was inhibited by high vicosity and the lack of mechanical stirring, resulting in mesoscopically-sharp interfaces. Interstitial melt in the partially crystallized host formed aureoles surrounding the pipes, with diameters of up to one meter. The aueroles show bulk chemical changes and partial re-equilibration. Characteristics of mafic emclaves within granites may be explained by such processes between partially crystallized magmas.
Publication Name: Journal of the Geological Society
Subject: Earth sciences
ISSN: 0016-7649
Year: 1992
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Petrology of a magma chamber: the plutonic complex of Guernsey (Channel Islands, UK)
Article Abstract:
The Guernsey Northern Plutonic Complex is a calc-alkaline intrusion within a metamorphic complex, composed of four roughly contemporaneous bodies: the St. Peter Port Gabbro, the Bordeau Diorite Group, the L'Ancresse Granodiorite and the Cobo Granite. The first two are remains of magma chambers, intrusion of which caused country-rock melt that mixed with crystallizing gabbro-diorite magma to form the latter two bodies. Northern Armorican Massif magmatic events during the late Cadomian may be explained by this acid-magma genesis.
Publication Name: Journal of the Geological Society
Subject: Earth sciences
ISSN: 0016-7649
Year: 1992
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Discussion on tectonothermal chronology of early Cadomian arc development in Guernsey and Sark, Channel Islands
Article Abstract:
An analysis describing research on tectonothermal chronology is presented. Earlier research present geochronological data depicting quartz-diorite stock formation in Guernsey and Sark, which are part of the UK's Channel Islands. It is shown that such rocks were emplaced and cooled as magmas during 600 Ma. This phenomena support conclusions that the Cadomian belt formed terranes in the orogeny's late stage.
Publication Name: Journal of the Geological Society
Subject: Earth sciences
ISSN: 0016-7649
Year: 1992
User Contributions:
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