Climbing Ripples Recording the Change of Tidal Current Condition in the Middle Pleistocene Shimosa Group, Japan

  1. B. W. Flemming and
  2. A. Bartholomä
  1. M. Yokokawa1,
  2. M. Kishi2,
  3. F. Masuda1 and
  4. M. Yamanaka3

Published Online: 14 APR 2009

DOI: 10.1002/9781444304138.ch20

Tidal Signatures in Modern and Ancient Sediments

Tidal Signatures in Modern and Ancient Sediments

How to Cite

Yokokawa, M., Kishi, M., Masuda, F. and Yamanaka, M. (1995) Climbing Ripples Recording the Change of Tidal Current Condition in the Middle Pleistocene Shimosa Group, Japan, in Tidal Signatures in Modern and Ancient Sediments (eds B. W. Flemming and A. Bartholomä), Blackwell Publishing Ltd., Oxford, UK. doi: 10.1002/9781444304138.ch20

Author Information

  1. 1

    Department of Earth and Space Science, Faculty of Science, Osaka University, Toyonaka, Osaka 560, Japan

  2. 2

    Department of Geology, Faculty of Science, Shinsyu University, Matsumoto 390, Japan

  3. 3

    Indonesian Oil Co. Ltd, Chiyoda, Tokyo 100, Japan

Publication History

  1. Published Online: 14 APR 2009
  2. Published Print: 11 AUG 1995

ISBN Information

Print ISBN: 9780865429789

Online ISBN: 9781444304138

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Keywords:

  • climbing ripples, recording change of tidal current condition pleistocene shimosa group;
  • climbing ripple cross-lamination, dominating lenticular sand body in middle Pleistocene Shimosa Group;
  • basal part of Jizodo Formation, resting on erosional surface and consisting tidal channel deposits;
  • neap-spring half cycle;
  • climbing ripple cross-laminae, occurring in four types;
  • climbing ripple cross-lamination, common in fluvial and deltaic environments

Summary

A lenticular sand body in the middle Pleistocene Shimosa Group in Japan, dominated by climbing ripple cross-lamination, is interpreted here as an estuarine or lagoonal deposit that accumulated under tidal influences. Based on the systematic change of sand-layer thickness in the alternation of sand and mud layers, two sets of four neap–spring tidal cycles are reconstructed from tidal flat deposits that occur just above the climbing-rippled sand;

The climbing ripple cross-laminae occur as four different types which signify variable current velocities and sediment supply. Isochrons can be drawn through the climbing-rippled sand along individual bedding surfaces on detailed tracings of the climbing ripple cross-laminae. The dominant types of climbing ripple cross-lamination vary along each isochron. Cyclic variations in current velocity during a single tidal cycle are demonstrated from the vertical evolution in the types of climbing ripple cross-lamination.