Implications of REE incorporation and host sediment influence on the origin and growth processes of ferromanganese nodules from Central Indian Ocean Basin

作     者：Simontini Sensarma Abhishek Saha Arghya Hazra Simontini Sensarma;Abhishek Saha;Arghya Hazra

作者机构：CSIR-National Institute of OceanographyDona PaulaGoa 403004India Indian Institute of ScienceBangaloreKarnataka 560012India School of EarthOcean and Atmospheric SciencesGoa UniversityGoa 403206India 

出 版 物：《Geoscience Frontiers》 (地学前缘（英文版）)

年 卷 期：2021年第12卷第3期

页      面：609-623页

核心收录：

学科分类：070704[理学-海洋地质] 0709[理学-地质学] 07[理学] 0707[理学-海洋科学] 0708[理学-地球物理学] 0704[理学-天文学] 

基　　金：the support of CSIR Senior Research Fellowship,India a part of the“Polymetallic Nodule:Survey and Exploration”project(GAP 2175)supported by Ministry of Earth Sciences,Govt.of India.This is NIO's contribution No.6633 

主　　题：Central Indian Ocean Basin Ferromanganese nodules Deep-sea sediments Rare earth elements Geochemical discrimination 

摘      要：This study presents new major,trace and REE data for thirty-five ferromanganese nodules recovered from areas representing three different sediment types(siliceous,red clay and their transition zone)in the Central Indian Ocean Basin(CIOB)to address their genetic aspects,classification,growth rate,nature of host sediments and influence of REE in the processes of nodule *** nodules from CIOB are mostly either hydrogenetic(metals coming from oxygenated bottom water)and diagenetic(metals coming from suboxic sediment pore water)or a combination of both,depending on the source of supply of ***,a number of biogeochemical processes mediate this supply of metals which again changes from time to time,making the nodule growth process highly *** study suggests that at the initial stage of nodule growth,host sediments do not play much role in controlling the growth processes for which REEs can enter both Mn and Fe oxyhydroxide phases ***,the bottom water signature is imprinted in these early formed nodules irrespective of their host sediment substrate but with gradual growth and burial in the sediment,the main mode of metal enrichment becomes diagenetic through sediment pore *** tends to increase the concentration of Mn,Ni and Cu over other elements which are retained in the sediment *** the REEs,Ce concentration of the nodules shows significant positive anomaly due to variation in redox potential and hence its magnitude can be used to get an idea about the metal enrichment procedure and the genetic type of the ***,based on host sediment only,not much difference is found in the magnitude of Ce anomaly in these *** the other hand,discrimination diagram,based on HFSE and REY chemistry,indicates that most of these nodules are of diagenetic origin under oxic condition with a trend towards hydrogenetic ***,the genetic type of the ferromanganese nodules from the CIOB are more effectively differentiated