The age of the Mesoproterozoic Stoer Group sedimentary and impact deposits, NW Scotland

John Parnell, Darren Mark, Anthony E. Fallick, Adrian Boyce, Scott Thackrey

Research output: Contribution to journalArticle

36 Citations (Scopus)

Abstract

The Mesoproterozoic Stoer Group of the 'Torridonian' has been dated at 1177 +/- 5 Ma (2 sigma), based on Ar-40/Ar-39 dating of authigenic K-feldspars precipitated in degassing structures within the Stac Fada Member, interpreted previously as an impact ejecta deposit. Fluid inclusion analysis of the K-feldspar shows that it precipitated from hot fluids, and so must immediately post-date emplacement of the ejecta blanket. The oxygen isotopic composition of K-feldspar is remarkably constant at 9.7 +/- 0.2 parts per thousand (V-SMOW) and is consistent with derivation from evaporated lake water. The new age supports previous determinations of 1199 +/- 70 Ma from Pb-Pb dating of limestone and 1180 Ma from palaeomagnetic data, but provides much higher precision.

Original languageEnglish
Pages (from-to)349-358
Number of pages10
JournalJournal of the Geological Society
Volume168
Issue number2
DOIs
Publication statusPublished - Mar 2011

Keywords

  • moine thrust zone
  • Northwest Scotland
  • fluid-flow
  • geochronology
  • pseudotachylite
  • geochemistry
  • provenance
  • seawater
  • events
  • origin

Cite this

The age of the Mesoproterozoic Stoer Group sedimentary and impact deposits, NW Scotland. / Parnell, John; Mark, Darren; Fallick, Anthony E.; Boyce, Adrian; Thackrey, Scott.

In: Journal of the Geological Society , Vol. 168, No. 2, 03.2011, p. 349-358.

Research output: Contribution to journalArticle

Parnell, John ; Mark, Darren ; Fallick, Anthony E. ; Boyce, Adrian ; Thackrey, Scott. / The age of the Mesoproterozoic Stoer Group sedimentary and impact deposits, NW Scotland. In: Journal of the Geological Society . 2011 ; Vol. 168, No. 2. pp. 349-358.
@article{e3f8b406d4c54dcc94312949f3148d84,
title = "The age of the Mesoproterozoic Stoer Group sedimentary and impact deposits, NW Scotland",
abstract = "The Mesoproterozoic Stoer Group of the 'Torridonian' has been dated at 1177 +/- 5 Ma (2 sigma), based on Ar-40/Ar-39 dating of authigenic K-feldspars precipitated in degassing structures within the Stac Fada Member, interpreted previously as an impact ejecta deposit. Fluid inclusion analysis of the K-feldspar shows that it precipitated from hot fluids, and so must immediately post-date emplacement of the ejecta blanket. The oxygen isotopic composition of K-feldspar is remarkably constant at 9.7 +/- 0.2 parts per thousand (V-SMOW) and is consistent with derivation from evaporated lake water. The new age supports previous determinations of 1199 +/- 70 Ma from Pb-Pb dating of limestone and 1180 Ma from palaeomagnetic data, but provides much higher precision.",
keywords = "moine thrust zone, Northwest Scotland, fluid-flow, geochronology, pseudotachylite, geochemistry, provenance, seawater, events, origin",
author = "John Parnell and Darren Mark and Fallick, {Anthony E.} and Adrian Boyce and Scott Thackrey",
year = "2011",
month = "3",
doi = "10.1144/0016-76492010-099",
language = "English",
volume = "168",
pages = "349--358",
journal = "Journal of the Geological Society",
issn = "0016-7649",
publisher = "Geological Society of London",
number = "2",

}

TY - JOUR

T1 - The age of the Mesoproterozoic Stoer Group sedimentary and impact deposits, NW Scotland

AU - Parnell, John

AU - Mark, Darren

AU - Fallick, Anthony E.

AU - Boyce, Adrian

AU - Thackrey, Scott

PY - 2011/3

Y1 - 2011/3

N2 - The Mesoproterozoic Stoer Group of the 'Torridonian' has been dated at 1177 +/- 5 Ma (2 sigma), based on Ar-40/Ar-39 dating of authigenic K-feldspars precipitated in degassing structures within the Stac Fada Member, interpreted previously as an impact ejecta deposit. Fluid inclusion analysis of the K-feldspar shows that it precipitated from hot fluids, and so must immediately post-date emplacement of the ejecta blanket. The oxygen isotopic composition of K-feldspar is remarkably constant at 9.7 +/- 0.2 parts per thousand (V-SMOW) and is consistent with derivation from evaporated lake water. The new age supports previous determinations of 1199 +/- 70 Ma from Pb-Pb dating of limestone and 1180 Ma from palaeomagnetic data, but provides much higher precision.

AB - The Mesoproterozoic Stoer Group of the 'Torridonian' has been dated at 1177 +/- 5 Ma (2 sigma), based on Ar-40/Ar-39 dating of authigenic K-feldspars precipitated in degassing structures within the Stac Fada Member, interpreted previously as an impact ejecta deposit. Fluid inclusion analysis of the K-feldspar shows that it precipitated from hot fluids, and so must immediately post-date emplacement of the ejecta blanket. The oxygen isotopic composition of K-feldspar is remarkably constant at 9.7 +/- 0.2 parts per thousand (V-SMOW) and is consistent with derivation from evaporated lake water. The new age supports previous determinations of 1199 +/- 70 Ma from Pb-Pb dating of limestone and 1180 Ma from palaeomagnetic data, but provides much higher precision.

KW - moine thrust zone

KW - Northwest Scotland

KW - fluid-flow

KW - geochronology

KW - pseudotachylite

KW - geochemistry

KW - provenance

KW - seawater

KW - events

KW - origin

U2 - 10.1144/0016-76492010-099

DO - 10.1144/0016-76492010-099

M3 - Article

VL - 168

SP - 349

EP - 358

JO - Journal of the Geological Society

JF - Journal of the Geological Society

SN - 0016-7649

IS - 2

ER -