TROPICAL GEOGRAPHY ›› 2016, Vol. 36 ›› Issue (3): 388-398.doi: 10.13284/j.cnki.rddl.002851

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Dating and Sedimentary Environment Reconstruction of Holocene Beach Profile in the Pearl River Estuary Islands

WAN Yixing1,ZHENG Zhuo1,XIAO Yiting2,TANG Yongjie1,CHEN Cong1   

  1. (1.Department of Earth Sciences and Geological Engineering,Sun Yat-sen University,Guangzhou 510275,China; 2.Zhuhai Museum,Zhuhai 519000,China)
  • Online:2016-05-05 Published:2016-05-05

Abstract: Holocene sand flat and sand dune deposits, which may be formed during the high sea level period in Holocene, are widely distributed in the coastal zone and islands of the Pearl River Estuary. These deposits contain rich information on Holocene marine transgression and environmental changes. Furthermore, rich Neolithic remains are found in these sediments in the islands around the Pearl River Estuary. Therefore, the coastal sandy marine deposits of Holocene, with evidences of both natural and cultural histories, have drawn great attention from scientists. In this paper, optical stimulated luminescence (OSL) dating and grain-size analysis were conducted. The results showed that the bottom of the coastal sandy marine deposits of Holocene might be formed more than 9 ka B.P. ago. Most of the OSL dating results showed that the Holocene sand flat and sandy eolian deposits were older than the Neolithic remains, which indicated that the former was formed before the latter. Another finding was that the overlying strata of the coastal sandy marine deposits often shifted rapidly to alluvial face of supratidal zone or dune at about 6.5 ka B.P., resulting in worsened grain-size sorting and great parameter fluctuations. The marine facies reached +4.8 m (modern elevation), which might be related to regional tectonic movement or the descending of sea level in Holocene. Combining grain-size analysis and archaeological excavation remains with other relevant records, the Holocene sedimentary environment was reconstructed; sea level change and differential tectonic movement, and relationship between man and nature in Holocene were revealed.

Key words: Pearl River Estuary Islands, Holocene, littoral deposit, grain-size analysis, optical stimulated luminescence, sea level