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Chinese Science Bulletin, Vol. 46
Supp(2001), 90-96
COASTAL PLAIN EVOLUTION IN SOUTHERN HAINAN
ISLAND, CHINA
WANG YING1, MARTINI I.P.2,
ZHU DAKUI1, ZHANG YONGZHAN1 and TANG WENWU1
1Key
Laboratory of Coast & Island Development of Ministry of Education of China,
Dept. of Geo & Ocean Sciences, Nanjing University, Nanjing 210093, China
2Department of Land Resource
Science, University of Guelph, Guelph, ON N1G 2W1,Canada
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 The coast of southern Hainan Island is
characterized by wide sandy embayments, which consist of (i) drowned valleys
bounded by steep bedrock hills and only locally receiving sediments, and
embayments of various dimensions covered either by (ii) alluvial-deltaic
deposits or by (iii) sands of coastal beach ridges/barriers and associated
elongated lagoons. During the late Tertiary-Pleistocene the area has experienced
isostatic and eustatic movements associated with neotectonics and climatic
changes. Such history is recorded in terraces at various altitudes (80, 40, 20 m
asl) and sequences of coastal sand ridges/baymouth bars. The Holocene variations
in sea level and climate are recorded in the dated coastal ridges, coral reef
and beachrock. Conditions suitable for reef development started about 8000 a BP.
The GPR profiles also show that the internal structures of the sand ridges have
composite nature being formed by several superimposed secondary ridges.
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