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6909877 
Journal Article 
Hydrothermal alteration of chevkinite-(Ce) in the Shuiquangou syenitic intrusion, northern China 
Jiang, N; , 
2006 
Yes 
Chemical Geology
ISSN: 0009-2541 
ELSEVIER SCIENCE BV 
AMSTERDAM 
227 
1-2 
100-112 
English 
WOS:000236406900007 
A rare-earth iron titanosilicate mineral closely associated with amphibole was found in two altered syenite samples from the Shuiquangou syenitic complex. Based on electron microprobe analyses, the mineral is chevkinite-(Ce). The mineral is altered and mantled by a corona of allanite-ilmenite-titanite-epidote-quartz. Mass balance calculations reveal that the former chevkinite was replaced directly by an allanite and ilmenite association (allanite-ilmenite zone) in the inner part of the corona. texture. It appears that during the replacement, Si and Ti were immobile, whereas Al, Fe, Mn, Mg and Ca were externally supplied and a proportion of REE and Th were transferred out of the former chevkinite. The released REE and Th become incorporated in allanite and titanite in the allanite-ilmenite-titanite mantle where allanite contains higher Nd, Sm and Y but lower La and Ce than that in the allanite-ilmenite zone, suggesting that redistribution of these elements took place and the mobility of Nd, Sm and Y is enhanced during hydrothermal alteration. (c) 2005 Elsevier B.V. All rights reserved. 
chevkinite-(Ce); corona system; hydrothermal alteration; mobilization