Edinburgh Research Archive logo

Edinburgh Research Archive

University of Edinburgh homecrest
View Item 
  •   ERA Home
  • Geosciences, School of
  • GeoSciences PhD thesis and dissertation collection
  • View Item
  •   ERA Home
  • Geosciences, School of
  • GeoSciences PhD thesis and dissertation collection
  • View Item
  • Login
JavaScript is disabled for your browser. Some features of this site may not work without it.

Aspects of the glacial and postglacial history of North-West Argyll

View/Open
Wian-Hobson1981.pdf (13.04Mb)
Wain-Hobson1981_FULL.pdf (13.05Mb)
Date
1981
Author
Wain-Hobson, Timothy
Metadata
Show full item record
Abstract
The Loch Lomond Advance limits and raised marine shorelines in N. W. Argyll have been mapped and surveyed. Radiocarbon dated Lateglacial and Postglacial pollen sites at Salen and Loch Shiel provide the vegetational history and chronology for the area. 14 Loch Lomond Advance glacier termini and associated limits were mapped using the distribution of hummocky and fluted moraine, together with a survey of erratic boulders. 83% of the reconstructed former glaciers had a southerly aspect relating to southerly snow-bearing winds. The average firnline gradient was 7.5m/km increasing in altitude towards the north-east; the average firnline height for the area was 369m. The Main Lateglacial Shoreline, formed during the Loch Lomond Stadial, slopes towards 270 with a gradient of 0.15m/km from 9m in the east to Om in the west of the area. It was formed by freeze-thaw action operating under exceptional conditions, and its formation was influenced by rock type. Two Postglacial shorelines are recognized : the Main Postglacial shoreline that slopes towards 270, from 14m to 8m with a gradient of 0.06m/km, and a lower shoreline at approximately 5m which has no definite gradient. An absolute Lateglacial pollen site at Salen, Ardnamurchan, shows an early pioneer community of Rumex, Salix, Gramineae and Cyperaceae species being replaced by an Empetrum heath during the Lateglacial Interstadial. Subsequent stadial conditions are reflected by open herb communities and the onset of coarse minerogenic sedimentation. This minerogenic influx ceased around 10,000 to 9,700 B.P. with a rapid recolonization of the surrounding area by pioneer herbs, then dwarf shrub and finally deciduous woodland. Middle and Late Postglacial vegetational development is recorded by lacustrine sediments from Loch Shiel where the fossil pollen record shows that a mixed deciduous woodland of Quercus, Alnus, Betula and Corylus was progressively cleared by man. Palaeomagnetic and chemical records were obtained from the site. The Main Postglacial Transgression flooded Loch Shiel resulting in the deposition of shells of the marine bivlave Thyasira flexonosa.
URI
http://hdl.handle.net/1842/10616
Collections
  • GeoSciences PhD thesis and dissertation collection

Library & University Collections HomeUniversity of Edinburgh Information Services Home
Privacy & Cookies | Takedown Policy | Accessibility | Contact
Privacy & Cookies
Takedown Policy
Accessibility
Contact
feed RSS Feeds

RSS Feed not available for this page

 

 

All of ERACommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsPublication TypeSponsorSupervisorsThis CollectionBy Issue DateAuthorsTitlesSubjectsPublication TypeSponsorSupervisors
LoginRegister

Library & University Collections HomeUniversity of Edinburgh Information Services Home
Privacy & Cookies | Takedown Policy | Accessibility | Contact
Privacy & Cookies
Takedown Policy
Accessibility
Contact
feed RSS Feeds

RSS Feed not available for this page