Onderzoeksoutput

Welkom op het expertplatform!

Dit platform verschaft informatie en kennis omtrent de WL expertisedomeinen 'hydraulica en sediment', 'havens en waterwegen', 'waterbouwkundige constructies', 'waterbeheer' en 'kustbescherming' - gaande van WL medewerkers met hun expertise, het curriculum van deze instelling, tot publicaties, projecten, data (op termijn) en evenementen waarin het WL betrokken is.

Het WL onderschrijft het belang van "open access" voor de ontsluiting van haar onderzoeksresultaten. Lees er meer over in ons openaccessbeleid.

log in

• 
  People
• 
  Curriculum
• 
  Projects
• 
  Data sets
• 
  Publications
• 
  Events

[ meld een fout in dit record ]

mandje (0): toevoegen | toon

---

Authigenic carbon entombed in methane-soaked sediments from the northeastern transform margin of the Guaymas Basin, Gulf of California Paull, C. K. ; Ussler, W. ; Peltzer, E. T. ; Brewer, P.G.; Keaten, R.; Mitts, P. J. ; Nealon, J. W.; Greinert, J.; Herguera, J.C.; Perez, M. E. (2007). Authigenic carbon entombed in methane-soaked sediments from the northeastern transform margin of the Guaymas Basin, Gulf of California. Deep-Sea Res., Part 2, Top. Stud. Oceanogr. 54(11-13): 1240-1267. dx.doi.org/10.1016/j.dsr2.2007.04.009 In: Deep-Sea Research, Part II. Topical Studies in Oceanography. Pergamon: Oxford. ISSN 0967-0645; e-ISSN 1879-0100

---

Beschikbaar in	Auteurs
VLIZ: Open Marine Archive 227783 [ download pdf ]

---

Trefwoord

Marien/Kust

Author keywords

Authigenic carbonate; Diagenesis; Gas vents; Guaymas Basin

---

Auteurs		Top
Paull, C. K. Ussler, W. Peltzer, E. T. Brewer, P.G.	Keaten, R. Mitts, P. J. Nealon, J. W.	Greinert, J. Herguera, J.C. Perez, M. E.

---

Abstract

Extensive ROV-based sampling and exploration of the seafloor was conducted along an eroded transform-parallel fault scarp on the northeastern side of the Guaymas Basin in the Gulf of California to observe the nature of fluids venting from the seafloor, measure the record left by methane-venting on the carbonates from this area, and determine the association with gas hydrate. One gas vent vigorous enough to generate a water-column gas plume traceable for over 800 m above the seafloor was found to emanate from a ~10-cm-wide orifice on the eroded scarp face. Sediment temperature measurements and topography on a sub-bottom reflector recorded in a transform-parallel seismic reflection profile identified a subsurface thermal anomaly beneath the gas vent. Active chemosynthetic biological communities (CBCs) and extensive authigenic carbonates that coalesce into distinct chemoherm structures were encountered elsewhere along the eroded transform-parallel scarp.The carbon isotopic composition of methane bubbles flowing vigorously from the gas vent (-53.6±0.8‰ PDB) is comparable to methane found in sediment cores taken within the CBCs distributed along the scarp (-51.9±8.1‰ PDB). However, the d13C value of the CO2 in the vent gas (+12.4±1.1‰ PDB) is very distinct from those for dissolved inorganic carbon (DIC) (-35.8‰ to -2.9‰ PDB) found elsewhere along the scarp, including underneath CBCs. The d13C values of the carbonate-rich sediments and rocks exposed on the seafloor today also span an unusually large range (-40.9‰ to +12.9‰ PDB) and suggest two distinct populations of authigenic carbonate materials were sampled. Unconsolidated sediments and some carbonate rocks, which have lithologic evidence for near-seafloor formation, have negative d13C values, while carbonate rocks that clearly formed in the subsurface have positive d13C values (up to +23.0‰) close to that measured for CO2 in the vent gas. There appears to be two carbon sources for the authigenic carbonates: (1) deeply-sourced, isotopically heavy CO2 (~+12‰); and (2) isotopically light DIC derived from local anaerobic oxidation of methane at the sulfate–methane interface in the shallow subsurface. Addition of isotopically light methane-derived carbon at the seafloor may completely mask the isotopically heavy CO2 signature (+12.4‰) in the underlying sediments. Thus, the authigenic carbonates may have formed from the same methane- and carbon dioxide-bearing fluid, but under different migration and alteration conditions, depending on how it migrated through the sediment column.

---

Alle informatie in het Integrated Marine Information System (IMIS) valt onder het VLIZ Privacy beleid

Top | Auteurs

IMIS is ontwikkeld en wordt gehost door het VLIZ.