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This photo shows the Chamonix valley in the French Alps -below the Mer de Glace glacier - a glacial trough. You can just make out the tiny post glacial river. This kind of river is called a misfit - there is no way that a river of this scale could have eroded a valley as large as this. Misfit steams are common throughout all glaciated areas such as north Wales. | |
| This model shows: some human impact modifications on a post glacial depositional area. The area is Oak ridges moraine which is just north of Toronto, Canada. There a lot of examples where kettle hole have been integrated into golf courses along with moraines. The glacial till is good for agriculture and gravel deposits are quarried. | |
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Sea Level changes after a glaciation. Worldwide (eustatically) thee be be arise in sea level leading to drowning of some glaciated valleys creating fiords for example. The diagram shows more local isostatic changes of sea level. This can cause uplift of glaciated areas (like north west Britain and Canada. the uplift from the last Ice Age is still occurring. Features like Hudson Bay may eventually become land. Landforms such as raised beaches are produced. Misfit rivers flowing down glaciated valley floors will have increased erosional power and may start to cut terraces into the land. The incised meanders in the Wye valley may have resulted from post glacial uplift. | |
| Raised
beach and glacial head at Porth Nanven, Cornwall.
Between ice advances of the Great Ice Age of the past couple of million
years there were warm periods. Notable among these is the time known as
the Ipswichian when sea level was about 12 metres higher than at present.
The rounded boulders in the cliff are the result of wave action during
that period, about 100,000 years ago. Above this is angular glacial head,
the results of tundra conditions pertaining during the succeeding glacial
period. The dividing line is quite distinct. The cliff is about 12 metres
high.
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