Glacial valley with rock basin forming a ribbon lake
Glacial deposition• Post-glacial landscapes contain many features “left behind” after glaciation• Formed of till and moraines – Unsorted and unstratified “soils” composed of different particle sizes – boulders, pebbles, clay
Deposition: erratics• Erratics are large “foreign” boulders transported by glaciers
Erratics – transported boulders Orhem – near Flaten
Deposition: moraines• Deposits of material left by retreating glaciers• Consist of unsorted till and erratics• Terminal/end moraine – Deposited by retreating glacier at its point of farthest reach – May create a dam holding a proglacial lake• Lateral moraines – Deposited along the sides of retreating glaciers
Eskers – gravel ridges• Meltwater forms a tunnel under a • After retreat of the ice, material glacial ice sheet collected in the tunnel is left to• Tunnel fills with rocks, sand and form a ridge gravel
Near SiljanAfter glacial retreat this sharp-ridged eskerWould have been above sea level
Eskers – economic benefits• Traditionally used as roads• Used for natural water filtration• Mined for materials – sand, gravel and stones for construction
Living in glaciated regions Description of landscape:• Most sedimentary rocks have been removed• Granites and gneiss rocks are less porous so the landscape tends to hold a lot of water• Makes the ground swampy, many lakes and soils are in general thinner• Glacial soils (clay) collects in valleys
Living in glaciated regions• Soils generally less fertile (soil is a resource)• There is less agricultural land – too much rock• Ground needs draining• High latitudes means shorter growing season• Wheat and grasses, forestry, livesto ck are more common
Making new land• The agricultural land shortage in Sweden during the 1800s was so acute that during the period 1880 – 1950 over 20,000 lakes were sunk to create new farmland
Alpine regions• Glaciation produces steep mountains with deep valleys• Difficult communications (roads etc)• Limited land for building• Snow for much of the year• High altitiudes lowers biodiversity and growing season• Greatest risks are from landslides (rock, mud, soil) and avalanches (snow)
Alpine regions• Advantage is the availability of hydropower• Modern communities turning to winter sports for as an economic resource
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