This study analyses seismic data to investigate the kinematic indicators within the mass transport deposits (MTDs) of the Donegal Barra Fan complex in the Rockall Trough, along the NW European continental margin. Five episodes of mega-scale MTDs (DBF-01, -02, -03, -04 and -05) are identified. DBF-01 is the largest MTD in the NW British continental margin, comprising 1907 km3 of sediments. Fold-and-thrusts were identified within the MTDs where they attain maximum thickness of c. 300–380 ms TWT, but not at the toe region. This indicates that local erosion and deceleration caused bulking up of the MTD volume, but the MTD was not fully arrested due to the high mobility of the mass flow. MTD thickness distribution and thrust fault orientations indicate source areas and flow direction of MTD. The MTDs show a compensational stacking pattern with earlier deposits influencing the position and flow direction of succeeding slides, suggesting that glaciogenic debris flows are sensitive to topographic variability. We propose that increased sediment input associated with at least five expansions of the British–Irish Ice Sheet to the shelf edge led to the development of these MTDs and that the youngest of them, DBF-05, corresponds to the Last Glacial Maximum.
|Title of host publication||Subaqueous Mass Movements and their Consequences: Advances in Process Understanding, Monitoring and Hazard Assessments: Advances in Process Understanding, Monitoring and Hazard Assessments|
|Editors||Aggeliki Georgiopoulou, LA Amy, Sara Benetti, JD Chaytor, MA Clare, D Gamboa, PDW Haughton, J Moernaut, JJ Mountjoy|
|Publisher||The Geological Society|
|Number of pages||20|
|Publication status||E-pub ahead of print - 18 Mar 2020|
|Name||Geological Society Special Publication|
Bibliographical noteFunding Information:
This publication derives from research supported in part by a research grant from Science Foundation Ireland (SFI) under Grant Number 13/RC/ 2092 and co-funded under the European Regional Development Fund and by iCRAG industry partners. SR also thanks the Irish Research Council Government of Ireland for the Postdoctoral Fellow Award Project No. GOIPD/2018/17).
© 2020 The Author(s).
Copyright 2020 Elsevier B.V., All rights reserved.
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