Draa Reconstruction, the Permian Yellow Sands, Northeast England

  1. K. Pye3 and
  2. N. Lancaster4
  1. T. Chrintz and
  2. L. B. Clemmensen

Published Online: 8 APR 2009

DOI: 10.1002/9781444303971.ch10

Aeolian Sediments: Ancient and Modern

Aeolian Sediments: Ancient and Modern

How to Cite

Chrintz, T. and Clemmensen, L. B. (1993) Draa Reconstruction, the Permian Yellow Sands, Northeast England, in Aeolian Sediments: Ancient and Modern (eds K. Pye and N. Lancaster), Blackwell Publishing Ltd., Oxford, UK. doi: 10.1002/9781444303971.ch10

Editor Information

  1. 3

    Reading, UK

  2. 4

    Reno, Nevada, USA

Author Information

  1. Institute of General Geology, University of Copenhagen, Øster Voldgade 10, DK-1350 Copenhagen K, Denmark

  1. NSR Consult, Sortemosevej 2, DK-3450, Allerød, Denmark

Publication History

  1. Published Online: 8 APR 2009
  2. Published Print: 27 MAY 1993

ISBN Information

Print ISBN: 9780632035441

Online ISBN: 9781444303971

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Keywords:

  • Draa reconstruction in Permian Yellow Sands, northeast England;
  • computer-graphics modelling - linear draas superimposed by sinuous linear dunes;
  • reconstruction of aeolian bedform type and behaviour from outcrop data and sedimentologists;
  • Yellow Sands - aeolian formation of Permian age;
  • aeolian architecture and aeolian architectural elements;
  • three-dimensional exposure of Yellow Sands (YS) in McCall's Quarry;
  • Early Permian Yellow Sands form - parallel-trending sand ridges representing linear draas;
  • sedimentary build-up of draa elements and superimposed aeolian bedforms

Summary

The lower Permian Yellow Sands of northeast England have been preserved as a number of 1.5–3.5 km wide and c.30m high, northeast—southwest trending linear draa ridges. The three-dimensional sedimentary build-up or aeolian architecture of these draa ridges is beautifully exposed in a number of large quarries. Studies of these outcrops allow a reconstruction of draa morphodynamics. The sediments in the draa ridges are composed of two superimposed inter-draa—draa element sets. The draa elements, which are the focus of this paper, are composed of abundant dune elements and minor inter-dune elements. The cross-stratified dune elements are between 0.5 and 11 m thick, with most elements having a thickness of between 2 and 4 m. In sections transverse to the draa ridge the dune elements are 2–40 m wide and have a trough-shaped lower bounding surface. The elements occur in both left-hand and right-hand versions and commonly form inter-digitating zones. In longitudinal sections the element has a planar lower bounding surface and appears to be of tabular geometry. The cross-beds of the dune elements display a squeezed bimodal pattern with one mode towards the northwest (313°) and the other mode towards the south-southeast (171°).

Computer-graphics modelling suggests that the linear draas were superimposed by sinuous linear dunes. These superimposed dunes were reversing and non-migrating (perfectly longitudinal) and had sinuosities that migrated along-crest. The draas and superimposed dunes were in equilibrium and apparently formed in a bimodal wind regime with alternating northwest or north winter winds and southeast or east summer winds. The resultant sand transport direction was parallel to the draa ridges, suggesting that these also were longitudinal bedforms during the final phase of draa sedimentation.