香港西博寮海峡WB7孔的第四纪沉积及硅藻研究

香港西搏寮海峡ＷＢ７孔第四纪沉积物中共有硅藻５４属，１８６个分类单位，该硅藻生物群以沿岸潮间带和近岸浅海种为主，伴有热性，暖热性浮游硅藻。依据硅藻在剖面中的分布特征，丰度及百分比含量变化，自下而上可划分出６个硅藻组合带。并明显反映该沉积时期的古气候与古环境特征，其中第５，６，带相当于全新世，其余４个带均属更新世。

QUATERNARY SEDIMENTS AND DIATOM STUDIES OF BOREHOLE WB7 IN THE WEST LAMMA CHANNEL,HONG KONG

A recent study on a marine borehole WB7 in the West Lamma Channel of Hong Kong has yielded a diverse and profuse diatom flora consisting of 54 genera, 186 taxa. The diatom assemblages are dominated by coastal,intertidal and near shore shallow water species including tropical (hot-philic) and subtropical (warm-philic) planktonic varieties. According to the distribution characteristics, abundance and mean percentage of diatoms, six diatom assemblage zones can be distinguished from top to bottom . The 5th and 6th diatom assemblage zones are assigned to Holocene, and other zones (1-4 zones) are considered to be Pleistocene in age.A more systematic and intensive study shows that the continuously sampled borehole may provide important information for the reconstruction of the high-resolution Quaternary stratigraphy, palaeoclimatology and palaeoenvironment in Hong Kong.Detailed diatom studies of hole WB7 are conducive to making more accurate correlation not only between the contemporaneous strata of the study area and other parts of Hong Kong,but also between Quaternary strata in the study area and the other related sedimentary basin in adjacent sea areas.