Glaciers

• Truncated Spur


  occur when a glacier cuts through an interlocking spur
• Glacial trough


  Steep sided, wide, flat bottomed u shaped valley formed by abrasion
• Ribbon Lake

  Long, deep, narrow lake- result from severe erosion of a glacial trough
• Hanging valley

  a smaller tributary valley- occur when a main valley is deeply eroded by a large glacier leaving smaller side valleys "hanging" above the main valley floor
• Glacial Transportation

  As glaciers move they transport material from one place to another
• What causes glacial deposition

  When glacier retreats and leaves behind crushed rock + sediments that they are carrying
• Outwash plain


  Areas of sorted sand + gravel deposited at the mouth of meltwater rivers.
• Abrasion

  When pebbles grind along a rock platform like sandpaper, over time the rock becomes smooth
• Plucking


  Occurs when meltwater beneath a glacier freezes around rock, loose rock is plucked away as the glacier moves over it
• Formation of Drumlins


  Glacier travels over moraine, it doesnt entrain the moraine because it doesnt have enough energy (near to the snout) + cant erode resistant rock. Deposits material all around the rock. Depositional feature, they tend to appear in groups called a swarm and are usually 500m long and 30-50m high
• interlocking spur


  mountain erodes vertically, creating V shaped valley, it winds around areas of resistant rock to create interlocking spurs. They are projections of high land that alternate from either side of a V shaped Valley
• Bulldozing

  As a glacier moves it pushes loose material ahead of it
• Glacial environment


  An area of land where glaciers shaped the land through processes of weathering, erosion, transportation+ deposition creating distinct landforms
• Rotational Slip

  Rotational movement of ice within the corrie results in plucking on the backwall and abrasion of the base of the corrie
• Corrie


  An armchair shaped hollow on a mountainside formed by erosion, rotational slip, freeze thaw weathering
• Arete


  Sharp knife like ridge formed between 2 corries cutting back through erosion + freeze thaw weathering
• Pyramidal peak

  Where several corries cut back to meet a central point = steep pyramid
• Tarn

  lake that occupies the rock basin of a corrie after glacial retreat
• Ablation till

  Where ice deposits the debris its transporting because the ice melts
• Lodgement till

  Where the glacier is overloaded with debris + squeezes it out benath the ice
• Formation of truncated spur

  Snow collects in nivitation hollows+ forms ice which slides down the mountainside. The ice erodes the mountain by abrasion + plucking and bulldozes the interlocking spurs away.
• Waterfalls formed

  River travels over a band of resistant + less resistant rock. Overtime the less resistant rock is eroded - more resistant rock is undercut. Resistant rock forms a slight overhang, due to force of hydrualic action a small plunge pool is formed. Overhang erodes- collapses into pool. Rocks + boulders added to the pool = erosion, process repeats + waterfall retreats = gorge
• what is a drumlin

  A small egg shaped hill, found in clusters on the flour of a glacial trough, consists of moraine that has been shaped by moving ice
• Formation of a corrie

  Snow accumulates in a sheltered hollow on a hillside- nivitation enlarges the hollow enabling more snow to collect. ICe freezes to the back wall due to freeze thaw weathering- plucking occurs + steepens backwall.Material is moved along under the hollow abrading the rock, deepening the hollow. Reduced erosion at the front of the corrie due to the ice being thicker + less eroded forms a raised lip- tarn forms
• V shaped valley

  A narrow steep sided valley formed as a result of vertical erosion by a stream or river.
• Erosion

  The wearing away + removal of material by a moving force.
• Deposition

  Material being transported by a river is dropped due to a loss of energy
• Gorge


  A narrow steep sided valley found downstream of a retreating waterfall
• Meander


  Bends in a river found mainly in lowland areas
• lateral moraine

  Forms at edges of the glacier- mostly consists of scree from freeze thaw weathering, forms low ridges on valley
• medial moraine


  When a tributary glacier joins the main glacier+ 2 lateral moraines merge- forms a ridge down centre of valley
• Ground moraine


  material transported below a glacier+ left when it melts= uneven hilly ground
• Till


  Unsorted material deposited by glacial ice- shows no stratification
• Outwash


  Deposits of gravel and sand carried by running water from the melting ice of a glacier
• Basal Slip


  Glacier sliding over the bed due to meltwater under the ice acting as a lubricant
• freeze thaw weathering


  when watr gets into the cracks of rocks - freezes + expands making rock weak and fall of
• Glacial movement in the summer

  Meltwater lubricates the glacier so it can slide down hill - basal slip. In hollows high on the valley side + rotational slip
• Glacial movement in winter

  Weight of the ice + effect of gravity causes ice to change shape
• Internal deformation


  Gravity+ the pressure of ice in the accumulation zone causes ice crystals to slide over each other in a series of parallel planes- can result in deep crevasses at surface
• Advance


  Snow accumulates over time, turns into ice + begins to flow outwards + downwards undet the pressure of its own weight