Abstract
Abstract Petrographic and stable‐isotope (δ13C, δ18O) patterns of carbonates from the Logatchev Hydrothermal Field (LHF), the Gakkel Ridge (GR), and a Late Devonian outcrop from the Frankenwald (Germany) were compared in an attempt to understand the genesis of carbonate minerals in marine volcanic rocks. Specifically, were the carbonate samples from modern sea floor settings and the Devonian analog of hydrothermal origin, low‐temperature abiogenic origin (as inferred for aragonite in serpentinites from elsewhere on the Mid‐Atlantic Ridge), or biogenic origin? Aragonite is the most abundant carbonate mineral in serpentinites from the two modern spreading ridges and occurs within massive sulfides of the LHF. The precipitation and preservation of aragonite suggests high Mg2+ and sulfate concentrations in fluids. Values of δ18OPDB as high as +5.3‰ for serpentinite‐hosted aragonite and as high as +4.2‰ for sulfide‐hosted aragonite are consistent with precipitation from cold seawater. Most of the corresponding ...
Published Version
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 call