厌氧沉积中有孔虫组合特征

厌氧沉积的有孔虫组合中,底栖有孔虫主要由Bolivina诸种和Buliminella tenuata组成,同时含有少量厌氧标志种Suggrunda eckisi;浮游有孔虫中以Globigerrina bulloides和G.quingueloba为数较多。底栖有孔虫与浮游有孔虫数量相比,浮游有孔虫数量很少。

THE CHARACTERISTICS OF FORAMINIFERAL ASSEMBLAGE IN THE ANOXIC SEDIMENTS

A core collected in the anoxic sediments from the central part of the Gulf of California was studied for its foraminiferal assemblage characteristics. The conclusion is as follows:A core collected in the anoxic sediments from the central part of the Gulf of California was studied for its foraminiferal assemblage characteristics. The conclusion is as follows: 1) The benthic foraminiferal assemblage is mainly composed of the following species:a: Bolivina subadvena, B, seminudo, and Buliminella tenuata are abundant and dominant.b: Bolivina argentea. B. spissa, Nonionella Stella, which are adapted to live in low dissolved oxygen environment, occur frequently. c: Suggrunda eckisi, which is an indicator of anoxic environment, is scanty.2) The planktonic foraminiferal assemblage is chiefly composed of Globigerina bull-aides,G.quinqueloba, and G. falconensis.3) The benthic foraminifera are more abundant than the planktonicforaminifera. 4) There is an inverse relationship between the rate of foraminiferaaccumulation and the fatio of silicoflageilale productivity.1) The benthic foraminiferal assemblage is mainly composed of the following species:a: Bolivina subadvena, B, seminudo, and Buliminella tenuata are abundant and dominant.b: Bolivina argentea. B. spissa, Nonionella Stella, which are adapted to live in low dissolved oxygen environment, occur frequently. c: Suggrunda eckisi, which is an indicator of anoxic environment, is scanty.2) The planktonic foraminiferal assemblage is chiefly composed of Globigerina bull-aides,G.quinqueloba, and G. falconensis.3) The benthic foraminifera are more abundant than the planktonicforaminifera. 4) There is an inverse relationship between the rate of foraminiferaaccumulation and the fatio of silicoflageilale productivity.