北黄海中部晚第四纪沉积物来源的稀土元素示踪

Tracing of Rare Earth Elements in Late Quaternary Sediments from Central North Yellow Sea

对北黄海中部DLC70-2孔166个沉积物样品进行了稀土元素测定,结合粒度参数研究,以探讨北黄海中部DLC70-2孔稀土元素地球化学特征和物质来源。结果表明：DLC70-2孔岩心稀土元素分布特征分别反映了末次间冰期（暖期）晚期以来北黄海海面波动以及沉积物物源的变化。判别函数和稀土元素配分模式表明北黄海DLC70-2孔沉积物物源主要为黄河源和鸭绿江源。La/Yb判别图解揭示DLC70-2孔上部0~32.10 m和下部37.60~60.72 m沉积物以黄河源为主,中部32.10~37.60 m和底部60.72~70.45 m沉积物以鸭绿江源为主。研究表明晚更新世以来黄河对北黄海中部沉积起着重要作用,而鸭绿江物质对北黄海中部沉积作用也有明显影响。

166 sediment samples were collected from core DLC70-2 in the central North Yellow Sea. Based on the measurements of Rare Earth Element（ REE）,the geochemical characteristics of REE and the material sources were analyzed from core DLC70-2 in the central North Yellow Sea. The results indicated that the REE from core DLC70-2（ 70. 60 meters in depth） can be divided into six layers,which reflect the fluctuation of sea level and the change of sediment sources in North Yellow Sea since late last interglacial cycle（ warm period）. The results showed that the sediments in core DLC70-2 were mainly derived from the Yellow River and the Yalu River. The sediments above the depth of 32. 10 m in upper and between 37. 60 ~ 60. 72 m in lower core DLC70-2 mainly belong to the Yellow River source; the sediments between 32. 10 ~ 37. 60 m in middle and between 60. 72 ~ 70. 45 m at the bottom of core DLC70-2 are mainly derived from the Yalu River source. It is concluded that the Yellow River is playing an important role in the central North Yellow Sea since Late Pleistocene and the Yalu River may indicate obviously influence to sedimentation in the central North Yellow Sea.