The Devensian Cold Stage Flashcards
When was the devensian cold stage?
115000 to 10000BP
What sort of temperatures defined the cold stage?
Generally cold but considerable fluctuation
What is an interstadial?
embedded periods of temporarily warm conditions
What are Stadials?
Embedded periods of cold conditions
When was the Chelford interstadial?
60 000BP
What trees were present during the Chelford interstadial?
Birch, pine and spruce
What are temperate species?
occurring in temperate latitudes
What are boreal species?
characterised by coniferous forests
What is the February mean temp the Chelford interstadial?
-10
What is the July mean temp of the Chelford interstadial?
16
What modern day environment is similar to the Chelford interstadial?
Scandinavian forests
What fauna was present in the Chelford interstadial?
Brown bear, fox, red deer, spotted hyena, reindeer, wooly rhino, horse, elk.
When was the Upton Warren interstadial?
42 000 - 38 000 BP
What are the July mean temps of the Upton Warren interstadial?
16
What are thermophilous species?
characteristic of warmer environments
What are arctic alpines?
natural distribution includes the arctic and more southerly mountain ranges
What trees were present in the Upton Warren interstadial??
No trees, possibly due to cold winter temperatures or herbivores
What was the vertebrate fauna in the Upton Warren interstadial?
mammoth, wooly rhino, Bison, reindeer, horse
When was the Dimlington Interstadial?
21000BP
What characterised the Dimlington Interstadial?
Long period of cold - maximum expansion of the devensian ice sheet
What was the devensian ice sheet?
Extensive ice coverage, polar desert or periglacial fringe
What happened to large herbivores during the Dimlington Interstadial?
Forced south
When was the last mammoth dated?
13000BP
When was the windermere interstadial?
13 000BP
What weather conditions characterised the windermere interstadial?
Was a rapid climactic warming, with July mean temp of 17-18 oC
What was the vegetation in the windermere?
Park tundra, copses of birch, more continuous vegetation , Pine woods in the south and east
What happened to ice caps in the windermere?
Strong reduction
What temp conditions characterised the Loch Lomond stadial?
Return to colder conditions for about 1000 years may have been due to disruption of the golf stream, July mean temp of 10-12, ended with rapid temp rise
What happened at the end of the loch lomond stadial?
Leads to post glacial flandrian period.
When did the postglacial period begin?
10 000 years ago
Who proposed a sub division of the postglacial period?
Axel Blytt and Rolf Sernander
What was the blytt and serenader subdivision based on?
stratigraphy of peatlands
