Stable Isotope Geochemistry


Options: Use Classic View

Use Monospaced Font
Show HTML Part by Default
Show All Mail Headers

Topic: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
David Gillikin <[log in to unmask]>
Wed, 30 Sep 2020 12:46:45 -0400
text/plain (1713 bytes) , text/html (3535 bytes)
Dear Isogeochem,

I’m curious how the community handles aragonite samples (phosphoric acid digestion). In my lab we compare aragonite to the calcite standards (NBS 18 and 19) and report those uncorrected values. I know several other labs that also do this, but I’ve also heard of labs that correct the data for the aragonite acid fractionation factor. If a user receives corrected data and then applies this to, for example, the Dettman et al. (1999) paleotemperature equation [based on Grossman & Ku 1986, which does not include an acid ff correction] they will get the wrong answers.

I know this has been discussed on this list in the past, but I have never seen a consensus- nor an indication of how many labs are correcting. What do you all think about this? Are there good reasons to not correct or to correct and what are the consequences? Most reviewers and journals require the values of standards to be included in publications, should we also require a statement about acid ff corrections / or non-corrections?

To help get an idea of how labs are operating, please fill in this short google form:



David P. Gillikin, Ph.D.
Professor of Geology
Director: Environmental Science, Policy & Engineering Program and 
Union College Stable Isotope Laboratory
Union College
Department of Geology
807 Union St.
Schenectady, NY 12308

Office phone: (518) 388-6679
Lab phone:     (518) 388-8741
email:  [log in to unmask]
Lab Website: