TY - JOUR
T1 - Hydrothermal methane and manganese variation in the plume over the superfast-spreading southern East Pacific Rise
AU - Ishibashi, Junichiro
AU - Wakita, Hiroshi
AU - Okamura, Kei
AU - Nakayama, Eiichiro
AU - Feely, Richard A.
AU - Lebon, Geoffrey T.
AU - Baker, Edward T.
AU - Marumo, Katsumi
N1 - Funding Information:
dent technicians of the R. V. Melville for their operations with expert seamanship. Thanks are also to the onboard scientists for their assistance in sample collecting during the cruise. We are obliged to Michael J. Mottl, who kindly provided us his manuscript, including methane and manganese dataset for the 9-1l”N EPR. Discussions with Tetsuro Urabe, John E. Lupton, and Toshitaka Gamo were very helpful. We thank Jean-Luc Charlou, Gary J. Massoth, and an anonymous reviewer for providing critical reviews of an earlier ver- sion of this paper. This study was conducted by the Special Coordination Fund from the STA, Japan. Chemical analyses were partially supported by the grant-in-aid for Scientific Research (No. 05403002) from the MESSC, Japan and the VENTS Pragram of the NOAA (Contribution number 1695 from the Pacific Marine Environmental Laboratory).
PY - 1997/2
Y1 - 1997/2
N2 - Onboard analyses of dissolved CH4 and Mn were conducted on the water column along the southern East Pacific Rise between 13°50′ and 18°40′S during the 1993 RIDGE FLUX Cruise. Many hydrothermal plumes were identified by chemical anomalies which overlie more than half of the surveyed ridge crest. The CH4/Mn ratio in the plumes shows wide variability ranges from about 0.05 to 3.9 due to wide range of CH4 concentration. The CH4-rich plumes were detected in the region of 16°00′-18°40′S where vigorous magmatic budget was confirmed by previous studies. Moreover, the CH4/Mn ratio of the plumes is highly correlated with other volatile/metal parameters such as the S/Fe ratio in plume particulate. These results strongly suggest that volatile input caused by magmatic perturbation to hydrothermal systems is responsible for the CH4/Mn variability in the southern EPR plumes, based on analogy of the case at the EPR 9°50′N site. The detection of several volatile-rich plumes and the extensive hydrothermal flux of volatile species are attributed to frequent magmatic events in the superfast spreading southern EPR.
AB - Onboard analyses of dissolved CH4 and Mn were conducted on the water column along the southern East Pacific Rise between 13°50′ and 18°40′S during the 1993 RIDGE FLUX Cruise. Many hydrothermal plumes were identified by chemical anomalies which overlie more than half of the surveyed ridge crest. The CH4/Mn ratio in the plumes shows wide variability ranges from about 0.05 to 3.9 due to wide range of CH4 concentration. The CH4-rich plumes were detected in the region of 16°00′-18°40′S where vigorous magmatic budget was confirmed by previous studies. Moreover, the CH4/Mn ratio of the plumes is highly correlated with other volatile/metal parameters such as the S/Fe ratio in plume particulate. These results strongly suggest that volatile input caused by magmatic perturbation to hydrothermal systems is responsible for the CH4/Mn variability in the southern EPR plumes, based on analogy of the case at the EPR 9°50′N site. The detection of several volatile-rich plumes and the extensive hydrothermal flux of volatile species are attributed to frequent magmatic events in the superfast spreading southern EPR.
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U2 - 10.1016/S0016-7037(96)00304-3
DO - 10.1016/S0016-7037(96)00304-3
M3 - Article
AN - SCOPUS:0030755793
SN - 0016-7037
VL - 61
SP - 485
EP - 500
JO - Geochimica et Cosmochimica Acta
JF - Geochimica et Cosmochimica Acta
IS - 3
ER -