南极海洋沉积物有机碳、氮特征及其古气候意义:以阿蒙森海为例  

Characteristics of Organic Carbon and Nitrogen in Antarctic Marine Sediments and Their Paleoclimatic Significance:A Case Study on the Amundsen Sea

作　　者：陈东 葛倩 雷子炎 张泳聪 韩喜彬 Chen Dong;Ge Qian;Lei Ziyan;Zhang Yongcong;Han Xibin(Key Laboratory of Submarine Geosciences,Second Institute of Oceanography,Ministry of Natural Resources,Hangzhou 310012,China)

机构地区：[1]自然资源部海底科学重点实验室,自然资源部第二海洋研究所,浙江杭州310012

出　　处：《地球科学》2024年第8期2925-2937,共13页Earth Science

基　　金：南极重点海域对气候变化的响应和影响(No.IRASCC2020-2022)。

摘　　要：为了更好地理解目前南极冰盖与气候的演化,以及为未来冰盖和气候变化的预测提供依据,通过对A11-02孔沉积物的有机碳、氮含量与稳定同位素值进行分析,结合粒度和地球化学元素等特征,探讨了中全新世以来西南极阿蒙森海沉积物有机质的来源及古气候意义.沉积物的δ^(13)C_(org)值指示有机质主要为海源输入,陆源有机质贡献相对较少.通过分析沉积物总有机碳含量及海源有机质含量变化,结合粒度及元素的变化特征,认为中全新世以来研究区古生产力的变化主要与气候变化有关,进而识别出4 750~4 500 a BP、3 600~3 400 a BP、2 250~2 000 a BP和600~400 a BP 4个寒冷阶段.To better understand the current evolution of the Antarctic ice sheet and climate,as well as to provide a basis fo future predictions of ice sheet and climate change,the organic carbon and nitrogen contents and stable isotope values of sediments from Hole A11-02 were analyzed,combined with the characteristics of grain size and geochemical elements,to explore the origin and paleoclimatic significance of organic matter in sediments from the Amundsen Sea,West Antarctic since the mid-Holocene.Theδ^(13)C_(org) value of the sediments indicates that the organic matter is mainly input from marine,and the contribution of terrestrial organic matter is relatively small.By analyzing the changes of sediment total organic carbon content and sea source organic matter content,combined with the variation characteristics of grain size and elements,it is believed that the change of paleoproductivity in the study area since the mid-Holocene is mainly related to climate change,and then it is identified that there are four cold stages at 4750-4500 a BP,3600-3400 a BP,2250-2000 a BP and 600-400 a BP.

关 键 词：阿蒙森海 有机碳、氮 有机质来源 古气候 中全新世 海洋地质 

分 类 号：P736[天文地球—海洋地质]