The photochemical reaction of volcanic sulfur dioxide may not be the only method of creating a mass independent fractionation of sulfur. (astrobio.net)
Assessment of diffusive isotopic fractionation in polar firn, and application to ice core trace gas records. (usap-dc.org)
This absence is reflected in numerous proxies, particularly the record of mass - independent fractionation of sulfur isotopes. (bobkopp.net)