Abstract
Some theoretic calculations on the oxygen isotopic composition of sulfate formed by inorganical oxidation of sulfide compounds and the results obtained by measuring the O 18/O 16 and the C 13/C 12 ratios of sulfates and carbonates associated in the salt incrustations around some fumarolic holes and in the calcareous marly flysch of an inactive geothermal manifestation (Larderello geothermal region) are reported here. Most of the analyzed samples show δO 18 (SO 4 2−) values which are explainable with sulfur or sulfide oxidation processes in the soil around the geothermal manifestation. In the case of sulfate with δO 18 negative value, a sulfur-oxidizing bacterial activity is probable. Only a few of the sulfates analyzed here have δO 18 values compatible with an oxidative process of sulfurous gases in steam or in condensed water solution. The limestone in the calcareous marly flysch shows evident oxygen and carbon isotope exchanges caused by geothermal water and steam and by the dissolved oxy-carbonic compounds. The positive δO 18-δC 13 correlation found reflects a proportional isotope exchange for the oxygen and carbon isotopes.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
