TSR Wiki > Study Help > Subjects and Revision > Revision Notes > Geography > Folding
- Folding is the process through which crustal rocks are bent.
- It produces anticlines (upfolds) and synclines (downfolds).
- Folding can produce very large mountains such as the Himalayas and the Rockies.
- Orogenesis is the process through which mountains are created. There are 3 periods of recent mountain building:
- Caledonian Period:310 million years ago. Most mountains created during this period have been destroyed through denudation. Remnants are the Scottish Highlands and the mountains of Scandinavia.
- Hercynian Period:240 million years ago. Examples include the Cape Ranges of South Africa, the Appalachians of the United States and Welsh mountains of the UK.
- Alpine Period:30 million years ago. Examples include the Alps and the Andes. Mountains created during this period are the highest because the have not yet been reduced by denudation.
- Folding takes place in three main stages:
- Initial bending of rocks as plates come together
- Simple Anticlines and Synclines are created.
- Formation of fold mountains-asymmetrical folds.
- Breaking of the folding results in faults/depressions.
- Peneplaination is the reduction of fold mountains to a level plain called a peneplain.
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