摘要
海洋沉积物地球化学研究,国外学者以往多集中于深海大洋;近年已逐渐对大陆架浅海引起注目。黄海是一个有代表性的半封闭型的陆架浅海,查明其地球化学特征将具有一定的意义。我们对比较均匀分布的62个表层沉积物样品进行了12种化学元素的分析,这些元素是Fe,Mn,Ti,P,Si,Cu,Co,Ni,Zn,Cr,Li和Vo Fe,Mn,Ti,P采用分光光度法测定;Cu,Co,Ni,Zn,Cr,Li采用原子吸收分光光度法测定;V采用发射光谱法测定;Si采用经典的重量法测定。
This work is chiefly based on the analytical results of the chemical composition of 62 sediment samples from the Huanghai Sea(Yellow Sea)to illustrate the following points:1.Abundance characteristic of elements in sediments of the study area.2.Variation regularity of elemental content in the sediments of different types——the law of grain-size control of elements.3.Geochemical province of the elements.4.Presence state of the elements.5.Rate of accumulation of the each element.6.Primary factor controlling the element distribution.The 12 chemical elements in the bottom sediments have been studied.Quantitative analyses of the elements Fe,Mn,Ti and P were made by colorimetry,those of Cu,Co,Ni,Zn,Cr,and Li by atomic absorption spectrophotometry,V by emission spectroscopy and Si by the usual gravimetrical method.The comparisons of the element abundances obtained in this study area with those in other sediments or rocks show that the abundance characteristic of elements in the study area is of the"philo-continental"property,i.e.the abundance pattern of elements is relatively close to that of the continent,but differ from that of the ocean.The grain size of sediments plays a distinct role in controlling the content of elements.The average contents of most elements increase gradually with decrease in grain size,only Si decreases with decreasing grain size.We call the variation regularity of element content with grain size"the law of grain-size control of elements".According to the elemental distribution,the area of study can be classified into 3 geochemical provinces:The first has high concentration for the most of elements and is covered with fine sediments.The second is characterized by the low concentration of the elements and covered by coarse sediments.The third province commonly occupies an intermediate position between the other two provinces and has a transition Character.The terrigenous fraction and authigenic fraction of the elements have been determined.The terrigefious detrital index of most elements is higher than the authigenic index.The clay minerals act as a reservoir for a majority of elements studied.A clear positive correlation among the elements was found.These facts indicate that most elements are present within the lattices of various terrigenous minerals,in particular within those of the clay minerals.Based on the rate of sedimentation,the concentration of the dements and the bulk sediment density,the accumulation rate of each element in the area of study have been calculated.It has been established that the primary factors controlling the element distribution are:(1)material source;(2)grain size;(3)mineral component;(4)hydrodynamic condition;and(5)physical-chemical environment of sedimentary region.
作者
赵一阳
喻德科
Zhao Yiyang;Yu Deke(Institute of Oceanology,Academia Sinica;Lanzhou Institute of Geology,Academia Sinica)
出处
《海洋与湖沼》
1983年第5期432-446,共15页
Oceanologia Et Limnologia Sinica
