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在山东半岛南部近岸海域QDZ03孔16.2m的沉积记录中,通过有孔虫和介形类化石群落的定量分析,探讨了研究区晚第四纪氧同位素(MIS)4期以来古沉积环境演变。在距今6万年前后开始的黄海海退期(相当于MIS4期),发育了有多次沉积间断的第1层(孔深16.2~12.0m)陆相地层。进入玉木亚间冰期(相当于MIS3)后,由于海平面的震荡上升,发育了第2层—第5层的滨岸弱海相—陆相沉积层,其中第5层上部可能包含部分MIS2期的产物,而MIS2期绝大部分沉积地层缺失。在距今12 000—11 000年前,海水逐渐由黄海入侵到青岛地区,发育了第6层下段(孔深9.1—8.6m)的海陆过渡相沉积层;在全新世最大洪泛面MFS来临之前(距今约11.0—9.0ka期间),海平面进一步上升,钻孔中发育了第6层中段(孔深8.6—7.7m)的滨岸相沉积层。随着距今6 000年前南黄海最大海泛面出现,后降至现今水平,并基本保持稳定状态,在黄河、近岸短源河流以及海岸带基岩侵蚀物等物质联合贡献下完成了南黄海中部泥质沉积体在近岸的延伸(7.7m以上),其中顶部约4.8m以上粒度粗化及与之相关的较多含量胶结壳有孔虫化石的出现,可能与约3 000—2 000年以来海岸带地区人类活动的加剧有关。
In the sedimentary record of QDZ03 hole 16.2m in the southern coastal area of Shandong Peninsula, through the quantitative analysis of foraminifer and ostracoda fossils community, the evolution of Paleo-sedimentary environment since the late Quaternary oxygen isotope (MIS) phase 4 was studied . In the Yellow Sea Reef (equivalent to the MIS4 period) dating back about 60,000 years ago, the first layer (pore depth 16.2 ~ 12.0m) terrestrial strata have been developed with many sedimentary discontinuities. After entering the Yamu sub-interglacial (equivalent to MIS3), due to the rise of sea level oscillations, the 2nd-5th weak coastal-continental sediments are developed, of which the upper part of Upper 5 may contain some MIS2 Of the product, and MIS2 most of the sedimentary formation is missing. In the 12,000-11,000 years ago, the seawater gradually invaded the area from the Yellow Sea to the Qingdao area, and developed the sea-land transitional sedimentary layer in the lower part of the sixth layer (pore depth of 9.1-8.6m); the MFS came during the Holocene maximum flood surface Before (about 11.0-9.0 ka ago), the sea level further increased, and a boreal sedimentary layer was developed in the middle of the sixth layer (8.6-7.7 m deep) in the borehole. With the onset of the largest sea surface in the South Yellow Sea 6,000 years ago, it has dropped to the present level and remained basically stable under the joint contribution of the Yellow River, the near-shore river and the bedrock erosion of the coastal zone The extension of the offshore muddy sediments in the southern part of the southern Yellow Sea (more than 7.7m), of which coarse grain size of about 4.8m at the top and coarsening of the foraminiferous fossils associated with it, may occur with about 3 000- Related to the intensification of human activities in the coastal zone since 2000.