Lake District Flashcards
What are the three different geology groups?
Skiddaw -> formed as black muds + sands, since raised + folded up by tectonic plates. Reach max height of 931m on Skiddaw. Mainly found in N mountains, smooth with many streams occupying deep gorges.
Borrowdale volcanic -> very hard lava + ash formed 450 mill yrs ago. Withstood erosion + make up highest mountains eg scafell, helvellyn + great gable
Windermere -> sedimentary mudstones, sand stones, milestones formed in the sea 420 mill yrs ago. Less resistant than BV + form a belt of foothills from Duddon estuary to Kendal.
What erosional features are there?
Helvellyn Range -> pyramidal peak. 11km long ridge over 600m high. Corrie glaciers formed + re-occupied corries from earlier glaciations
Nethermost cove -> corrie containing red tarn. Ice from red tarn flowed into a valley forming valley glacier large enough to create small glacial trough
Norfolk Island -> Roche moutonée, lake Olswater
What depositional features are there?
drumlins -> as ice moved radically in all directions. Some rock cores consist of till
Moraines -> valleys contain as deposited during glacial retreat 11,000 yrs ago
Lateral moraine -> right bank of Langstrath Valley = retained distinctive appearance due to mass movement processes on alley side
Recessional moraine -> end of Blea Water Tarn
Medial moraine -> runs down centre of wythburn valley, deposited during final retreat of valley glacial
Erratics -> from BVG transported 30km SE
