摘要
选择北海半岛南流江河口、半岛近岸海域及涠洲岛附近海域为对象,研究河海水混合过程中稀土元素的某些地球化学特征。结果表明,水体中稀土元素主要以悬浮颗粒态存在,溶解态稀土含量及轻、重稀土含量之比从河流到海洋逐渐降低。溶解态稀土含量在南流江河口低盐度区因胶体絮凝而下降,在中高盐度区,颗粒物解吸或部分溶解引起含量上升;pH值对其亦有影响。溶解态稀土分布模式以重稀土相对富集为特征,在此基础上存在中稀土富集,是源区铁锰氧化物和水体中有机胶体共同作用的结果,Ce正异常与水体中有机物有关,Eu负异常是对源区岩石分布模式特征的继承。而原水中稀土含量变化相对复杂,与水动力状况有关,分布模式较为一致,表明河流颗粒物存在均一化趋势。
The geochemical features of REEs in Nanliu River mouth and the coastal water along Beihai peninsula and Weizhou island in Guangxi were studied. The results were concluded as follows： （1） REEs in the coastal water along Beihai peninsula and Weizhou island were mainly absorbed by suspended particles. The contents of dissolved REEs and values of L/H decreased from fiver to sea. （2） The contents of dissolved REEs decreased with lower salinity and increased with higher salinity at Nanliu River mouth. The pH also had influence on them. （3） The distribution patterns of dissolved REEs showed moderate REEs enriched, which were caused by Fe-Mn oxides from source rocks and organic colloid in water. The positive Ce-anomaly was ascribed to the effects of organic compounds and the negative Eu-anomaly was the characteristics of source rocks. （4） The variations of the contents in unfiltered water were complicated while distribution patterns were similar. It was caused by the homogenization of suspended particles.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2008年第6期753-759,共7页
Journal of the Chinese Society of Rare Earths
基金
国家自然科学基金项目(40676070)资助
关键词
北海半岛
水体
分布
稀土
Beihai peninsula
water
distribution
rare earths
