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通过对北冰洋楚科奇海和白令海 41个表层沉积样品中的有孔虫、介形类等钙质微体化石和硅藻、放射虫、海绵骨针等硅质微体化石的定量分析 ,发现表层沉积中浮游有孔虫几乎缺失 ,这可能与该区表层生产力相对低、碳酸盐溶解作用较强有关 ,而底栖有孔虫和硅质微体化石的丰度分布则明显受表层沉积物类型、表层初级生物生产力和碳酸盐溶解作用所控制。其中 ,北冰洋楚科奇海陆架区有孔虫丰度和分异度低 ,含少量浅水介形类 ,放射虫在陆架浅水区缺失 ,但含有较多硅藻和海绵骨针等其它硅质微体化石 ,反映该区由于海冰、表层海水温度较冷而导致表层初级生产力相对低。白令海陆坡区底栖有孔虫丰度比楚科奇海高一个数量级 ,底栖有孔虫分异度也相对高 ,硅藻、放射虫、海绵骨针等硅质微体化石的丰度与钙质化石一样 ,其丰度比楚科奇海明显高 ,反映表层初级生产力相对高。根据白令海陆坡区底栖有孔虫和硅质微体化石丰度、底栖有孔虫胶结质壳比值的水深变化 ,推测该区碳酸盐溶跃层和补偿深度 (CCD)相对浅 ,分别位于水深 2 0 0 0 m和 380 0 m处
Based on the quantitative analysis of calcareous microfossils, such as foraminiferal and ostracods, and diatoms, radiolarians and sponge spicules from 41 surface sedimentary samples in the Chukchi and Arctic of the Bering Sea, it was found that There were almost no planktonic foraminifera in the surface sediments, which may be related to the relatively low surface productivity and carbonate dissolution in this area, while the abundance distribution of benthic foraminiferal and siliceous microfossils obviously affected by surface sediment Species type, primary biological productivity and carbonate dissolution. Among them, the Arctic Ocean Chukchi Sea shelf area has low abundance and diversity of foraminifera, with a small amount of shallow water-bearing species, radiolarian lack of shallow shelves, but contains more diatom and sponge spicules other silicon micro- Body fossil, reflecting the area due to sea ice, surface sea water temperature is relatively cold leading to the surface primary productivity is relatively low. The abundance of benthic foraminifera in the Bering Sea slope is one order of magnitude higher than that of the Chukchi Sea, and the relative abundance of benthic foraminifera is also relatively high. The abundance of silica microfossils such as diatoms, radiolarian spongles and sponge spicules As with calcareous fossils, its abundance is significantly higher than that of Chukchi, reflecting the relatively high primary productivity of the surface. According to the water depth changes of benthic foraminifer and siliceous fossil abundance and the ratio of the benthic foraminiferous cementitious shell in the Bering Sea slope, it is presumed that the carbonate dissolved layer and compensation depth (CCD) are relatively shallow Respectively, at water depths of 200 m and 380 m