Partial thermal resetting of 40Ar/39Ar mineral ages in western Spitsbergen, Svalbard : Possible evidence for tertiary metamorphism
By: Dallmeyer, R.D
.
Material type: 
ArticleDescription: 587-593p ; Illustration.Subject(s): Mineral ages - Western Spitsbergen | Evidence - Tertiary metamorphism - Western Spitsbergen | Caledonian metamorphic rock - Northwest Spitsbergen | High grade metamorphism - Northwest Spitsbergen
In:
Geological magazine : Vol. 126 Iss. 1-6 Year. 1989Summary: Abstract
Hornblende and muscovite within high-grade Caledonian metamorphic rocks exposed in Albert I Land (northwest Spitsbergen) display internally concordant 40Ar/39Ar age spectra providing no record of any post-Silurian thermal history. Both minerals record 420−425 Ma plateau ages indicating that relatively rapid cooling followed Silurian metamorphism. Muscovite within some metamorphic sequences exposed within the Tertiary tectonic zone of Oscar II Land (west-central Spitsbergen) displays a low-temperature 40Ar/39Ar age spectra discordance suggestive of a slight, post-Caledonian thermal disturbance. This is consistent with a post-Palaeozoic thermal overprint documented elsewhere in Oscar II Land and indicates that, at least locally, metamorphism may have accompanied the Tertiary orogeny.
| Item type | Current location | Collection | Call number | Status | Date due | Barcode |
|---|---|---|---|---|---|---|
Article
|
Library and Information Centre Periodical Section | Bound Journal Collection | Not for loan | 002528_123 | ||
Serials/Scientific Journal
|
Library and Information Centre Periodical Section | Bound Journal Collection | 550 GEO (Browse shelf) | Available | 002528 |
Abstract
Hornblende and muscovite within high-grade Caledonian metamorphic rocks exposed in Albert I Land (northwest Spitsbergen) display internally concordant 40Ar/39Ar age spectra providing no record of any post-Silurian thermal history. Both minerals record 420−425 Ma plateau ages indicating that relatively rapid cooling followed Silurian metamorphism. Muscovite within some metamorphic sequences exposed within the Tertiary tectonic zone of Oscar II Land (west-central Spitsbergen) displays a low-temperature 40Ar/39Ar age spectra discordance suggestive of a slight, post-Caledonian thermal disturbance. This is consistent with a post-Palaeozoic thermal overprint documented elsewhere in Oscar II Land and indicates that, at least locally, metamorphism may have accompanied the Tertiary orogeny.
There are no comments for this item.