Fold basins in Late–Devensian glacimarine sediments at Shieldhall, Glasgow

摘要: Synopsis The paper describes fold basins (non-diastrophic centroclinal folds) at least 80 metres long, 50 wide and 10 deep developed in a Late–Devensian glacimarine sequence consisting of sea-bed clays silts with underlying submarine glacial outwash sands. bedding the sediments dips centroclinally angles generally ranging from 15° to 45°. Locally near basin margins, excess 70° are recorded. Two modes origin for discussed. Firstly, they may represent sites kettle holes formed when ice, buried sands long period during which were deposited, finally melted. Secondly, have broad scale deformation resulted extensive loading rapidly deposited into mobile Basin formation involving development is favoured. Water melting ice interstitial pore water, trapped initially by overlying thick seal cohesive deposits, escaped upwards downwarping basins. This caused diapiric movement local oversteepening margins.