10.6084/m9.figshare.3454130.v1
S. Walker
S.
Walker
M. F. Thirlwall
M. F.
Thirlwall
R. A. Strachan
R. A.
Strachan
A. F. Bird
A. F.
Bird
Evidence from Rb–Sr mineral ages for multiple orogenic events in the Caledonides of Shetland, Scotland
Geological Society of London
2016
Grampian accretionary orogenic events
mainland Scotland
Scandian nappe pile
Uyea Shear Zone
East Mainland Succession
Silurian Moine Thrust
North Atlantic Caledonides
Wester Keolka Shear Zone
Yell Sound Group
Geology
2016-06-21 11:55:15
Dataset
https://geolsoc.figshare.com/articles/dataset/Evidence_from_Rb_Sr_mineral_ages_for_multiple_orogenic_events_in_the_Caledonides_of_Shetland_Scotland/3454130
<p>Shetland occupies a unique central location within the North Atlantic Caledonides. Thirty-three new high-precision Rb–Sr mineral
ages indicate a polyorogenic history. Ages of 723–702 Ma obtained from the vicinity of the Wester Keolka Shear Zone indicate
a Neoproterozoic (Knoydartian) age and preclude its correlation with the Silurian Moine Thrust. Ordovician ages of <em>c</em>. 480–443 Ma obtained from the Yell Sound Group and the East Mainland Succession constrain deformation fabrics and metamorphic
assemblages to have formed during Grampian accretionary orogenic events, broadly contemporaneously with orogenesis of the
Dalradian Supergroup in Ireland and mainland Scotland. The relative paucity of Silurian ages is attributed to a likely location
at a high structural level in the Scandian nappe pile relative to mainland Scotland. Ages of <em>c</em>. 416 and <em>c</em>. 411 Ma for the Uyea Shear Zone suggest a late orogenic evolution that has more in common with East Greenland and Norway
than with northern mainland Scotland.
</p> <p><strong>Supplementary material:</strong> Detailed appraisal of biotite petrography is available at <a href="http://www.geolsoc.org.uk/SUP18887">http://www.geolsoc.org.uk/SUP18887</a>.
</p>