通过对渤海莱州湾GK138、GK111及GK95孔的255个沉积物样品中的有孔虫定量统计分析,共鉴定出底栖有孔虫15属32种.根据底栖有孔虫的丰度和分异度等分布特征和AMS14C和光释光(OSL)测年结果,揭示晚第四纪以来研究区共发育3套海相地层,分别是中更新世晚期的第三海相层、晚更新世的第二海相层和全新世的第一海相层,通过与全球海面变化曲线对比,发现其与MIS7、MIS5和MIS1阶段的高海面有良好的对应关系.样品的Q型聚类及主成分分析划分出3组代表不同沉积环境的有孔虫化石组合,第Ⅲ化石组合带为中更新世晚期海侵的产物,为河口-滨岸浅海环境.第Ⅱ化石组合为晚更新世海侵的产物,为潮间带-潮下带沉积环境,第Ⅰ化石组合带为潮上带-潮间带沉积环境.海相地层顶、底板高程和厚度的分析结果显示中更新世晚期至晚更新世期间发生过不同期次、不同强度的构造活动,而进入全新世以后构造活动相对减弱.%Based on the quantitative statistical analysis of benthic foraminifera fauna in 255 samples that were taken from three boreholes (GK138,GK111,GK95) of the Laizhou Bay of Bohai Sea,15 genera and 32 species of benthic foraminiferal fossils are identified.Species richness and diversity of benthic foraminifera and age data of AMS14 C and OSL,show three marine sedimentary beds,which can be respectively interpreted as Marine Bed 3(M3) deposited in the Later Mid-Pleistocene phase,Marine Bed 2(M2) in the Late Pleistocene phase and Marine Bed 1(M1) in the Holocene phase in ascending.By the comparison with the global sea-level change curve,M3,M2 and M1 have a good correspondence with the high sea stage of MIS (Marine Isotope Stage) 7,MIS 5 and MIS 1.The analysis results of thickness and elevation of roof and floor in the marine sedimentary beds show that the multi-stage and the different intensity of tectonic activities occurred from Later Mid-Pleistocene to Late Pleistocene,and tectonic activity was relatively weaken in the Holocene.Three microfossil assemblages related to different environments were identified based on multivariate quantitative analyses (mainly Q-mode cluster analysis and principal component analysis):assemblage Ⅲ is characterized by a river mouth-supratidal or paralic environment or a relatively small scale of Later Mid-Pleistocene transgression,assemblage Ⅱ was the product of the Late Pleistocene transgression and indicates a intertidal-subtidal environment,and assemblage Ⅰ is characterized by the supratidal-intertidal environment,which mainly occurred during Holocene marine transgression.
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