ZIMSEC O Level Geography Notes: Landforms resulting from Weathering: Kopjes
- Tors/kopjes/castle kopjes are inselbergs.
- Tors the same as kopjes even though some books make an attempt to distinguish between the two.
- Different names are applied in different localities to what are essentially the same landforms.
- Kopje is an Afrikaans word meaning a small and isolated hill made of granite rock piles.
- Tor is a Scotish word meaning hill.
- They appear appear as a large, free-standing rock outcrop that rises abruptly from the surrounding smooth and gentle slopes of a rounded hill summit or ridge crest.
- They are resistant rock features that have been made by weathering.
- They are usually less than 5 meters in height.
- They are a result of marginal subsurface weathering of domed landforms.
- Granite intrusions are weathered beneath the surface due to acidic water penetrating joints in the rock.
- When the rock is exposed the rotten parts are washed away by erosion.
- Weathering continues in the form of both mechanical and chemical weathering.
- Because these rocks have rectangular joints, chemical and mechanical weathering takes place in these joints.
- The regolith (weathered/rotten parts of the rock) is stripped away by erosion to form a kopje/tor.
- If the joints are close together the whole mass collapses and is washed away,
- However if the joints a wider blocks of rocks fall away from the main rock creating tors/kopjes.
- They are sometimes remnants of dwalas and bornhardts such as Dwalas/ Bornhadts and inselbergs/Monadnocks.
- They are usually found in temperate latitudes.
- Because of their morphology (shape) kopjes are known is some localities as castle kopjes.
- These are a result of continued weathering on kopjes and tors.
- If the joints in the rocks that form kopjes and tors are further apart massive chunks of rock may withstand the denudation processes to remain balancing one on top of another.
- An example are the Balancing Rocks in Epworth.
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