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Title: Data report: concentration and carbon isotopic composition in pore fluids from IODP Expedition 385
During International Ocean Discovery Program (IODP) Expedition 385, sediments from Guaymas Basin were sampled with the goal of understanding the role of sill emplacement and fluid flow, as well as its associated temperature and fluid circulation regimes, on subsurface carbon mobilization and preservation of organic-rich sediments. We report on the concentration and isotopic composition of dissolved inorganic carbon (DIC) in pore fluids from Sites U1545 and U1546, which were drilled in the northern basin; Sites U1547 and U1548, which sampled an active hydrothermal vent site; Sites U1549 and U1552, which targeted cold seeps; and Site U1550, which was drilled in the axial trough. There is large variability in the DIC concentrations. The highest values were recorded at Sites U1549, U1550 (up to ~75 mM), and U1552 (~169 mM). The isotopic composition of the DIC (δ13CDIC) ranges −23.50‰ to 22.64‰ referenced to Vienna Peedee belemnite. At all locations outside Ringvent Site U1547, depletions in δ13CDIC values typically coincide with the sulfate–methane transition zone (SMTZ). Enrichment in δ13CDIC above seawater values, indicative of ongoing microbial methanogenesis, was recorded below the SMTZ at all locations except Ringvent.  more » « less
Award ID(s):
1326927
PAR ID:
10359578
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Proceedings of the International Ocean Discovery Program
Volume:
385
Issue:
201
ISSN:
2377-3189
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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