A tectonic model for Scandanian terrane accretion in the northern Scandinavian Caledonides
Article Abstract:
Argon-40 and Argon-39 ages of muscovite and hornblende from the Caledonian nappe stack of Troms, northern Norway range from 425-370 Ma, indicating Early Silurian-Late Devonian post-metamorphic cooling. Rapid nappe exhumation from peak metamorphism during the Laurentia-Baltoscandia collision was evinced in a structural unit exhibiting ages of 425-421 Ma. Other muscovite ages indicate the relaxation of the 350 degree-Centigrade isotherm through the thickened Caledonian crust. Enhanced fluid flow and retrogression characterized the majorinternal thrusts at this time.
Publication Name: Journal of the Geological Society
Subject: Earth sciences
ISSN: 0016-7649
Year: 1992
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A major Late Devonian-Early Carboniferous (Hercynian) thermotectonic event at the NW margin of the Arabian-Nubian shield: evidence from zircon fission track dating
Article Abstract:
Evidence for a major Hercynian thermotectonic event is provided by zircon fission track (ZFT) data from southern Israel and Sinai. Late Devonian-Early Carboniferous (328-373 Ma) ages are obtained, indicating total ZFT clock resetting and temperature constraints of about 225 degrees Centigrade prior to rapid cooling. The data suggest that the Cambrian strata underwent sub-Carboniferous erosion, with thermal gradients reaching up to greater than 50 degrees Centigrade. This event was limited to a narrow area between the Gulf of Suez and northeast Syria.
Publication Name: Tectonics
Subject: Earth sciences
ISSN: 0278-7407
Year: 1992
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Diachronous cleavage development in the Robertson Bay terrane, Northern Victoria Land, Antarctica: tectonic implications
Article Abstract:
The Robertson Bay terrane in Northern Victoria Land is composed of a thick Cambrian-Ordovician distal turbidity sequence that is folded vertically and characterized by regionally penetrative cleavage development. Argon dating of terrane slate/phyllite indicates that such development is diachronous. Ross orogeny models, that propose the southwesterly subduction of the Robertson Bay terrane beneath the Bowers terrane, bear out this regional age variation.
Publication Name: Tectonics
Subject: Earth sciences
ISSN: 0278-7407
Year: 1992
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- Abstracts: An 40Ar/39Ar thermochronology of the Ofoten-Troms region: implications for the terrane amalgamation and extensional collapse of the northern Scandinavian Caledonides
- Abstracts: Upper mantle reflector structure and origin beneath the Scottish Caledonides. Does the Great Glen fault really disrupt Moho and upper mantle structure?
- Abstracts: Kinematic evolution of the lower plate during intracontinental subduction: an example from the Scandinavian Caledonides
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