渤海湾西部现代有孔虫群垂直分带的特征及其对全新世海面、地质环境变化的指示

Modern foraminifera assemblages: vertical zonation and its indication for Holocene sea level and geoenvironmental reconstruction in Bohai Bay, China

对渤海湾西部潮间带和浅海区106个表层底质样品的活体与死有孔虫进行分析,筛选出8个优势种。利用死体有孔虫研究了优势种随水深(高程)变化的垂直分布特征,讨论了不同属种、不同有孔虫垂直组合带与地质环境、海面的定量关系。结果表明,有孔虫属种和组合的指示范围决定其作为地质环境及海面变化指标的灵敏性和精度。确立了研究区有孔虫海相性评价指数及与水深(高程)的相关性。根据对研究结果的实例应用的分析,恢复了研究区一个局部地点的相对海面变化曲线,为全新世地质环境和海面变化研究提供了一个新的尝试案例。

8 dominant species were chosen based on the living and dead foraminifera analyses from 106 surface samples, taken from the intertidal zone and shallow sea on the west of Bohai Bay. The vertical distribution features of the dead foraminifera depending on the water depth （altitude） were studied, and a quantitative relation of different foraminiferal species between vertical assemblage zones and sea level and geoenvironment was discussed. The results show that the indicative scope of the foraminiferal species and assemblages defines its sensitivity and precision as an indicator of geoenvironment and sea level （altitude） change. The marine index of the foraminifera and its relativity with altitude were constructed. The relative sea level curve of the study area was obtained by a case study. It has further proved that foraminifera can be an indicator for the sea level and geoenvironmental reconstruction.