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(a) Identify two erosional features in glaciated lowlands
(b) Describe how the following features are formed:
(i) Outwash plain
(ii) Moraine-dammed lake

Answer Text:
a) - Ice -eroded plains
- Depression.
- Roche mountonee
- Crag and tail
. b i) - Large ice sheets halt their movements on gently sloping low lands. They melt at the
terminus (snow line) - The melt water from the surface and sub glacial parts of ice sheet flow beyond the terminus carrying along fine materials.
- The melt water deposits fine materials as it flows over gentle land.
- Pre-existing valleys and depressions are eventually buried by these fluvio - glacial
deposits.
- When ice sheet retreats it leaves behind an undulating plain of unconsolidated clay, silt, sand and gravel which is called an outwash plain
ii) - Glacial erosion widens a valley.
- When glacier reaches its terminus it begin to melt.
- Ice remains stagnant at the point of melting for several years.
- Moraine is deposited across widened valley to form a ridge of terminal moraine.
- Glacier begins to retreat towards snow field as it melts.
- The melt water accumulates behind the ridge of terminal moraine to form a moraine dammed lake.