The study on the early diagenetic processes in REY-rich sediments in Southeast Pacific Ocean and its indicative significance
As potential mineral resources,rare earth elements(REY)and yttrium enriched sediments in the deep sea have attracted a lot of attention in recent years.It has been shown by studies that the enrichment process of REY is most likely to occur at the sediment-water interface(SWI),however studies on the early diagenetic processes in REY-enriched sediments are in general lacking.In this paper,we collected two short sediment cores in REY-en-riched sediments in the Southeast Pacific Ocean,then we had conducted an in-depth analysis on the early diagenes-is process of REY at SWI and its influence on the enrichment mechanism of REY in deep-sea sediment.The low Fe,Mn concentration and high Mo,U and V concentration in pore-water indicated that the sediment cores were in oxic environment.Compared to the REY in overlying water column,the dissolved REY in pore-water characterized by a middle rare earth elements(MREE).In sediment,phosphate phase is the main phase of REY,while the distribution pattern of REY in pore-water may be controlled by the phosphate content in sediments.Our results show that dur-ing the early diagenetic processes,the REY initially combined with Fe/Mn phase and other phases re-released into the pore-water,which is subsequently adsorbed by and eventually buried with the phosphate phase.Therefore,the early diagenetic process is an important mechanism of REY enrichment in deep sea sediments.
early diagenetic processpore-waterrare earth elementssedimentSoutheast Pacific Ocean
万方数据
维普
