Disturbance (geology)

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.British Geological Survey 1:50,000 map sheets 214, 215, 231 'Merthyr Tydfil', 232 'Abergavenny', 247 'Swansea' & accompanying memoirs The SilverdaleBrenchley PJ & Rawson PF (eds) 2006 The Geology of England and Wales (2nd edn), The Geological Society, London (p135) and Burtreeford disturbancessheets 25 & 31 of 1:50K scale map geological map series of British Geological Survey are found in northern England.

List of disturbances The following named features comprise both faulting and folding;

+Sortable table of named disturbancesDisturbance name CountyCountryBGS map sheetbook reference/sBurtreeford DisturbanceEnglandE&W 19, 31Caerbryn DisturbanceCarmarthenshireWalesE&W 230Carreg Cennen DisturbanceWalesE&W 230Clun Forest DisturbanceShropshireEnglandE&W 165BGS memoir sheet 165Cribarth DisturbanceWalesE&W 230, 231Llandyfaelog DisturbanceCarmarthenshireWalesE&W 231Llannon (or Llanon) DisturbanceCarmarthenshireWalesE&W 230Neath DisturbanceWalesE&W 231Pontyclerc DisturbanceCarmarthenshireWalesE&W 230Saron DisturbanceCarmarthenshireWalesE&W 230Silverdale DisturbanceEnglandE&W 25Stockdale DisturbanceEnglandGCR29, p205Cossey et al, 2004, British Lower Carboniferous Stratigraphy, Geological Conservation Review Series, no 29, Joint Nature Conservation Committee, PeterboroughTrimsaran DisturbanceWales

See also List of geological folds in Great Britain

References