摘要
本文根据泥质沉积物中的磷酸盐组份比值与水体盐度密切相关的“沉积磷酸盐法”理论,采用土壤中磷酸盐的分级测定方法.对我国不同地区的早第三纪和第四纪沉积,进行了试验和沉积相的研究.结果是这些沉积物的古盐度与现代海洋沉积的盐度十分接近,而与现代淡水湖的盐度有明显差异,此结论与古生物及岩石地层沉积环境的综合分析结论是吻合的.由此证实沉积磷酸盐法作为古盐度指标具有一定的可靠性.
This article gives an account of an experiment which was carried out according to a theory of Sedimentary Phosphate Method (SPM) advanced by Nelson ( 1967) , a theory which was closely related to the ratio of phosphate fractions in argillaceous sediments and to the water salinity. While applying Jackson's (1957) system of phosphate fractionation determined in soil, the writers made some necessary improvements and simplification. Qualitative and quantitative appraisals of salinity and studies of sedimentary facies have been done on the modern deposits in regions of the South China Sea, the Yellow Sea, the Poyang Lake and the Hongze Lake as well as the deposits in different regions and in different periods ranging from the Quaternary of Tai Lake to the Early Tertiary of Tarimu Basin in Xinjiang and the Dongpu Depression in Henan Province. Experimental results revealed that the paleosalinity of the first mem- ber of the Early Tertiary Shahejie Formation at the Dongpu Depression in Henan and the Early Tertiary Tarimu Basin in Xinjiang was most similar to the salinity of the modern marine deposits, differing notably, however, from that of the freshwater of the Poyang Lake and Hongze Lake. This conclusion tallies with what has been synthetically analysed with respect to paleontology and the rock-forming depositional environments, thus testifying to the fact that the sedimentary phosphate method (SPM) as an indicator of paleosalinity may be regarded as something to be relied or depended upon. In this paper are also discussed the limitations of the method mentioned above as well as the points for attention while it is in use.
出处
《沉积学报》
CAS
CSCD
北大核心
1989年第4期113-119,共7页
Acta Sedimentologica Sinica
