%0 Journal Article
%T LATERITE FORMATION PROCESS IN SOUTHERN CHINA AND ITS RARE EARTH ELEMENT (REE) GEOCHEMISTRY<br>南方红土形成过程及其稀土元素地球化学
%A Yang Yuangen
%A Liu Congqiang
%A Yuan Keneng
%A He Zhenli
%A <br>杨元根
%A 刘丛强
%A 袁可能
%A 何振立
%J 第四纪研究
%D 2000
%I 
%X Chemical index of alteration (CIA) for different laterites released that laterites derived from basalt, Quatemary red clay and gneiss hold the highest CIA values,followed by granite laterites, then limestone and sandstone; other parameters SiO2/Al2O3,Al2O3/Fe2O3 and R2O3 /SiO2 ratio exposed the results which agreed well with that of CIA; Normalized transitions for major element components were catried out to remove the false phenomena of enrichment or loss of inert components from which three stages for laterizahon process can be inferred, that is, leaching stage of CaO followed by leaching of K2O, Na2O, MgO and primary desiliciflcation with Al-enricIiment, then the stage of desilicification and Fe and Al-enrichment.Total REE contents in laterites were much higher than that in their basal rocks, and gneiss, limestone and gdrite laterites possessed the highest contents of total REE but lowest in sediments rich in qtal, t tests show no obviously REE content variance in different laterite horizons; Soluble REE richened apparently in the lower horizons in laterite profiles, varied a lot with their derived basal rocks and extremely obviously exponential relation can be observed between total REE and soluble REE also extremely obviously positive relations can exist for soluble REE with CIA values and clay contents while extremely obviously negative relations with organic matter, pH values and Al2O3 / Fe2O3 ratios, which means soluble REE contents can be an effective indicator for laterization sthength. Total REE contents showed extremely apparent negative relations with SiO2/ Al2O3, Al2O3/ Fe2O3 ratios and positive with R2O3 /SiO2 ratio which reflected the reliance on parent rocks. After being normalized tusitiory laterite REE can be seen leached in the eary laterization stage while enriched in the later stage. The main chemical forms of REE in laterites were mainly crysed phases which inherited from parent rocks, while other forms mainly related closely with laterization process.
%K laterite
%K weathering
%K REE geochemistry<br>红土
%K 风化作用
%K 稀土元素地球化学
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&cid=621CF755B1A341E5&jid=EA07051745CDC8D89D5F01A3A4CFE6A9&aid=A7A1BF131D7F75EF&yid=9806D0D4EAA9BED3&vid=A04140E723CB732E&iid=94C357A881DFC066&sid=8F2250DA83AF77B8&eid=03436AC72A659ACA&journal_id=1001-7410&journal_name=第四纪研究&referenced_num=32&reference_num=19