福建南日水道及其邻近海域表层沉积物地球化学特征及物源指示

福建南日水道是沟通兴化湾与台湾海峡能量和物质转换的重要航道，其海洋沉积物所包含的物源信息对探讨中国东部海域的水文特征及沉积特点具有重要意义。本文对南日水道及其邻近海域兴化湾的海洋表层沉积物的粒度与粒径参数、主微量元素及稀土元素组成进行了分析。结果显示：南日水道沉积物以砂质粉砂为主，但远岸海域浅部存在细粒粘土质粉砂，水动力条件总体中等，横向上，远岸相对近岸水动力条件减弱；兴化湾沉积物粒度随深度加深呈变粗趋势，水动力条件由浅至深也逐渐加强，但总体相对南日水道较弱。对研究区表层沉积物主微量元素进行的R型因子分析结果显示：南日水道沉积物受粗碎屑组分（如石英、生物碎屑等）、细粒陆源碎屑矿物、水动力条件以及海洋化学沉积作用因素制约；兴化湾沉积物受陆源碎屑沉积、海洋生物沉积作用因素制约。稀土元素配分图以及分异参数物源判别图显示南日水道与兴化湾沉积物的源区较为相似，主要受浙闽河流物质以及浙闽沿岸流携带的长江源物质的控制。

Geochemical characteristics and provenance indication of surface sediments in Nanri channel and its adjacent sea area, Fujian Province

The Nanri Channel in Fujian Province is an important channel for energy and material conversion between the Xinghua Bay and the Taiwan Strait. The provenance information contained in the marine sediments of Nanri channel will aid to discuss the hydrological and sedimentary characteristics of the eastern China Sea. This work analyzed the grain size and parameters, major and trace elements, and rare earth elements of the surface sediments from the Nanri channel and its adjacent Xinghua Bay. Results show that the sediments in Nanri channel are mainly composed of sandy silt, with fine-grained clayey silt in the shallow part of the offshore area. The hydrodynamic condition is generally moderate, which is weaker in the offshore area than that in the inshore area horizonally. In contrast, the sediment grain size in Xinghua Bay becomes coarser with depth, and the hydrodynamic condition is gradually strengthened from shallow to deep, which is generally weaker than that in Nanri Channel. The major and trace elements of the surface sediments in the study areas were analyzed by R-factor method. The sediments in Nanri Channel were controlled by coarse clastic components (such as quartz, bioclasts, etc.), fine-grained terrigenous clastic minerals, hydrodynamic conditions and marine chemical sedimentation, while the sediments in Xinghua Bay were mainly affected by terrigenous clastic sedimentation and marine biological sedimentation. The REE distribution pattern and the provenance discrimination diagram show that the provenance of the Nanri channel is similar to that of the Xinghua Bay, which is mainly controlled by the materials from the Zhejiang-Fujian River and the Yangtze River carried by the Zhejiang-Fujian Coastal Current.