Sequence Stratigraphy, Chemostratigraphy and Facies Analysis of Cambrian Series 2 - Series 3 Boundary Strata in Northwestern Scotland

Authors

Luke E. Faggetter, University of Leeds
Paul B. Wignall, University of Leeds
Sara B. Pruss, Smith CollegeFollow
Yadong Sun, Friedrich-Alexander-Universität Erlangen-Nürnberg
Robert J. Raine, Geological Survey of Northern Ireland
Robert J. Newton, University of Leeds
Mike Widdowson, University of Hull
Michael M. Joachimski, Friedrich-Alexander-Universität Erlangen-Nürnberg
Paul M. Smith, University of Oxford

Document Type

Article

Publication Date

5-1-2018

Publication Title

Geological Magazine

Abstract

Globally, the Series 2 - Series 3 boundary of the Cambrian System coincides with a major carbon isotope excursion, sea-level changes and trilobite extinctions. Here we examine the sedimentology, sequence stratigraphy and carbon isotope record of this interval in the Cambrian strata (Durness Group) of NW Scotland. Carbonate carbon isotope data from the lower part of the Durness Group (Ghrudaidh Formation) show that the shallow-marine, Laurentian margin carbonates record two linked sea-level and carbon isotopic events. Whilst the carbon isotope excursions are not as pronounced as those expressed elsewhere, correlation with global records (Sauk I - Sauk II boundary and Olenellus biostratigraphic constraint) identifies them as representing the local expression of the ROECE and DICE. The upper part of the ROECE is recorded in the basal Ghrudaidh Formation whilst the DICE is seen around 30m above the base of this unit. Both carbon isotope excursions co-occur with surfaces interpreted to record regressive-transgressive events that produced amalgamated sequence boundaries and ravinement/flooding surfaces overlain by conglomerates of reworked intraclasts. The ROECE has been linked with redlichiid and olenellid trilobite extinctions, but in NW Scotland, Olenellus is found after the negative peak of the carbon isotope excursion but before sequence boundary formation.

Keywords

DICE, Durness Group, ROECE, Scotland, trilobite extinction

Volume

155

Issue

4

First Page

865

Last Page

877

DOI

10.1017/S0016756816000947

ISSN

00167568

Rights

© Cambridge University Press 2016

Comments

Archived as published. Open access article

Recommended Citation

Faggetter, Luke E.; Wignall, Paul B.; Pruss, Sara B.; Sun, Yadong; Raine, Robert J.; Newton, Robert J.; Widdowson, Mike; Joachimski, Michael M.; and Smith, Paul M., "Sequence Stratigraphy, Chemostratigraphy and Facies Analysis of Cambrian Series 2 - Series 3 Boundary Strata in Northwestern Scotland" (2018). Geosciences: Faculty Publications, Smith College, Northampton, MA.
https://scholarworks.smith.edu/geo_facpubs/120