The following is a short discussion of REE analyses in inclusion fluids that was held in February, 1998.

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Dear all,

Does anyone out there who does ICP-MS analyses, have some information on analyzing REE in fluid inclusions in quartz grains.
Thanks.

Regards, Rune

Rune S. Selbekk Phone job. (+47) 77 64 44 21
Department of Geology Phone private (+47) 77 63 25 57
University of Tromso Fax.(+47) 77 64 56 00
Dramsveien 201
N-9000 Tromso E-mail: runes@ibg.uit.no
Norway

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Check out Geoch. Cosmo. Acta, v.57, 4513-4516

Edwin Roedder

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Please see Ghazi, et al., "Determination of rare earth elements in fluid inclusions by ICP-MS," Geochimica et Cosmochimica Acta, v. 57, pp. 4513-4516, 1993, for some tips.

Dave Vanko

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One paper you can check out is:

Banks et al 1994, REE composition of an aqueous magmatic fluid: A fluid inclusion study from the Capitan Pluton NM USA. Chemical Geology 113 p259-272

It has references to other papers by Banks on the methods used.

Andy Campbell

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Dear Rune, et al.

Further to Ed Roedder's reply, we also looked at ICP-MS analysis of fluid inclusions, following crush-leach: see Banks et al., Chemical Geology v.113, 259-272.

Our main concern was that adsorbtion onto the fresh quartz surfaces would be a serious problem. When Simon Bottrell was developing the LaCl3 leach solution to combat adsorbtion of Ca onto quartz (which IS A MAJOR problem for crush-leach), part of the logic was that La would saturate the adsorbtion sites. Well, it certainly seems to work to help Ca-analysis, but much to our surprise and delight it turned out that adsorbtion of REE from crush-leach solutions is not such a big problem as we feared. Dave Banks experimented grinding quartz in standard solutions with a range of HNO3 concentrations, and spiked with Nb, to suppress adsorbtion, but basically found that although adsorbtion occurred, especially for the LREE, it was not a big problem - the acidified leach solutions that Ed Roedder used will probably have done the job quite adequately, although we spiked with a small amount of Nb to be sure.

The ICP-MS analysis is not the problem, as always it is getting a pure sample with a single inclusion population that is the stumbling block.

Bruce Yardley

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