西沙群岛西科1井第四纪钙藻及其生态功能

对西沙群岛西科1井第四纪地层中的钙藻进行了初步研究, 共鉴定钙藻3科7属, 包括红藻门珊瑚藻科让氏藻属、蟹手藻属、珊瑚藻属、石枝藻属和石孔藻属, 以及绿藻门松藻科仙掌藻属和粗枝藻科伞轴藻属.通过对地层中钙藻形态功能的分析, 西科1井第四纪早期海水较深, 沉积环境为礁前相, 中期外礁坪和内礁坪交替沉积, 至晚期出现短时间的泻湖相之后沉积环境演变为礁后滩相.西科1井第四纪钙藻在造礁功能上主要体现在2个方面: (1)通过自身的钙化作用, 为生物礁的生长供应微小碳酸盐颗粒沉积物; (2)利用自身形成的节片结构和生物捆扎-粘结结构参与造礁. 

Quaternary Calcareous Algae from Well Xike-1 in Xisha Islands and Its Ecological Function

This paper presents our study of the calcareous algae in the well Xike-1, Xisha Islands, and it is found that there are 3 families and 7 genera in the Quaternary sedimentary deposit mainly including Rhodophyta Corallinaceae Jania, Amphiroa, Corallina, Lithothamnium, Lithoporella and Rhodophyta Chlorophyta Codiaceae Halimeda and Dasycladaceae Cymopolia. Analysis of the stratigraphic distribution of the calcareous algae in the well Xike-1 shows that it was forereef facies in the early Quaternary and then became the outer reef flat facies alternated with the inner reef flat facies in the middle Quaternary. In the later Quaternary, it developed into the backreef beach facies mixed with brief lagoon facies. Calcareous algae played the role of providing calcareous skeleton debris and building reef framework.