Cyclic Sedimentation in Three Neogene Basins in California

  1. David I. M. Macdonald
  1. J. Robert Dodd1 and
  2. Robert J. Stanton Jr2

Published Online: 14 APR 2009

DOI: 10.1002/9781444303896.ch12

Sedimentation, Tectonics and Eustasy: Sea-Level Changes at Active Margins

Sedimentation, Tectonics and Eustasy: Sea-Level Changes at Active Margins

How to Cite

Dodd, J. R. and Stanton, R. J. (1991) Cyclic Sedimentation in Three Neogene Basins in California, in Sedimentation, Tectonics and Eustasy: Sea-Level Changes at Active Margins (ed D. I. M. Macdonald), Blackwell Publishing Ltd., Oxford, UK. doi: 10.1002/9781444303896.ch12

Editor Information

  1. British Antarctic Survey, Cambridge, UK

Author Information

  1. 1

    Department of Geology, Indiana University, Bloomington, Indiana 47405, USA

  2. 2

    Department of Geology, Texas A & M University, College Station, Texas 77843, USA

Publication History

  1. Published Online: 14 APR 2009
  2. Published Print: 13 JUN 1991

ISBN Information

Print ISBN: 9780632030170

Online ISBN: 9781444303896

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Keywords:

  • cyclic sedimentation in three neogene basins in California;
  • Neogene strata - for cyclic sedimentation study;
  • San Joaquin Basin - during Eocene time as fore-arc basin;
  • Etchegoin and San Joaquin Formations - conglomerate, sandstone, siltstone, mudstone;
  • Merced Formation distribution and other units in San Francisco area;
  • correlation between stratigraphic sections in San Joaquin, Eel River, and Merced Basins;
  • sedimentary cycles in Neogene San Joaquin, Eel River, and Merced Basins of California

Summary

Neogene marine deposition in California largely took place in basins that formed in middle to late Miocene time, reached maximum depth by early Pliocene time, and then progressively filled and shoaled to non-marine conditions during Pleistocene time. Cyclic patterns are poorly developed in the transgressive phase of basin history but are well developed in some basins in the later part of the regressive phases, when shelf conditions were attained. The late Miocene to Pleistocene cycles in the San Joaquin (about 12 cycles), Merced (about 30 cycles), and Eel River (about 4 cycles) Basins reflect differences in the history and palaeogeographic settings of the individual basins. Apparent eustatic cycles are best developed in the Merced Basin, where subsidence and depositional rates are nearly balanced. A larger tectonic component may be responsible for the apparently longer cycles in the other basins. These basins particularly illustrate the fact that for eustatic cycles to be well developed, the depositional surface should cross either of the datum levels of shoreline, or storm wave-base. If deposition is entirely below wave base or above sea level, even though both of these datums fluctuated during eustatic cycles, cyclicity in the sedimentology and fossil record will be poorly developed. If deposition is entirely between the two datums, cyclicity may be well developed, but this depends to a large extent on the intrinsic basin characteristics of sediment supply and wave and current action.