Water Escape Structures in the Context of a Depositional Model of a Mass Flow Dominated Conglomeratic Fan-Delta (Abrioja Formation, Pliocene, Almeria Basin, SE Spain)

  1. Dorrik A. V. Stow
  1. George Postma

Published Online: 29 APR 2009

DOI: 10.1002/9781444304473.ch23

Deep-Water Turbidite Systems

Deep-Water Turbidite Systems

How to Cite

Postma, G. (1991) Water Escape Structures in the Context of a Depositional Model of a Mass Flow Dominated Conglomeratic Fan-Delta (Abrioja Formation, Pliocene, Almeria Basin, SE Spain), in Deep-Water Turbidite Systems (ed D. A. V. Stow), Blackwell Publishing Ltd., Oxford, UK. doi: 10.1002/9781444304473.ch23

Editor Information

  1. Department of Geology, University of Southampton, UK

Author Information

  1. Geological Institute of Amsterdam, Nieuwe Prinsengracht 130, 1018 VZ Amsterdam, The Netherlands

Publication History

  1. Published Online: 29 APR 2009
  2. Published Print: 11 NOV 1991

ISBN Information

Print ISBN: 9780632032624

Online ISBN: 9781444304473

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Keywords:

  • pebbly sediments of shallow marine Abrioja fan-delta;
  • fluid escape structures;
  • local liquefaction and fluidization;
  • rapid deposition;
  • rapid sediment accumulation

Summary

Pebbly sediments of the shallow marine Abrioja fan-delta show pockets (bowl-shaped structures, partly filled with pebbles) and pillars (elongate structures, filled with sand and pebbles). These structures are most abundant in pebbly sediments deposited on a steep slope (ca. 25°–10°) and are absent in conglomerates deposited on a slope of ca. 6° and less, although they are present in the pelitic top of these beds.

The pocket and pillar structures are interpreted as fluid escape structures originating from local liquefaction and fluidization, processes which are favoured by rapid deposition, rapid sediment accumulation, the presence of less permeable layers and an immature sediment texture.

These conditions are met in conglomeratic fan-deltas, which have steep slopes with immature sediments. It is concluded that the presence of fluid escape structures in conglomeratic sediments may indicate a steep depositional slope.