Disturbance (geology)

Not to be confused with Disturbance (archaeology).

In geology, a disturbance is a linear zone of disturbed rock strata stretching for many miles across country which comprises a combination of folding and faulting. The British Geological Survey record a number of such features in South Wales including the Neath Disturbance, Pontyclerc Disturbance, Carreg Cennen Disturbance and the Cribarth Disturbance, the latter sometimes also known (at least in part) as the Tawe Valley or Swansea Valley Disturbance. The southwestward continuation of the Carreg Cennen Disturbance is known as the Llandyfaelog Disturbance.

Other examples in Wales and the border counties of England include the Clun Forest, Saron, Trimsaran and Llannon (or 'Llanon') disturbances.^[1] The Silverdale^[2] and Burtreeford disturbances^[3] are found in northern England.

List of disturbances

The following named features comprise both faulting and folding;

Sortable table of named disturbances

Disturbance name	County	Country	BGS map sheet	book reference/s
Burtreeford Disturbance		England	E&W 19, 31
Caerbryn Disturbance	Carmarthenshire	Wales	E&W 230
Carreg Cennen Disturbance		Wales	E&W 230
Clun Forest Disturbance	Shropshire	England	E&W 165	BGS memoir sheet 165[4]
Cribarth Disturbance		Wales	E&W 230, 231
Llandyfaelog Disturbance	Carmarthenshire	Wales	E&W 231
Llannon (or Llanon) Disturbance	Carmarthenshire	Wales	E&W 230
Neath Disturbance		Wales	E&W 231
Pontyclerc Disturbance	Carmarthenshire	Wales	E&W 230
Saron Disturbance	Carmarthenshire	Wales	E&W 230
Silverdale Disturbance		England	E&W 25
Stockdale Disturbance		England		GCR29, p205[5]
Trimsaran Disturbance		Wales

See also

• List of geological folds in Great Britain

References

1. British Geological Survey 1:50,000 map sheets 214, 215, 231 'Merthyr Tydfil', 232 'Abergavenny', 247 'Swansea' & accompanying memoirs
2. Brenchley PJ & Rawson PF (eds) 2006 The Geology of England and Wales (2nd edn), The Geological Society, London (p135)
3. sheets 25 & 31 of 1:50K scale map geological map series of British Geological Survey
4. Cave, R; Hains, B A (2001). Geology of the Country around Montgomery and the Ordovician rocks of the Shelve area (1st ed.). London: BGS; NERC;The Stationery Office. p. 127. ISBN 0118845527.
5. Cossey et al, 2004, British Lower Carboniferous Stratigraphy, Geological Conservation Review Series, no 29, Joint Nature Conservation Committee, Peterborough