Loading...
Please wait, while we are loading the content...
Similar Documents
Extensive hydrothermal activity revealed by multi-tracer survey in the Wallis and Futuna region (SW Pacific)
| Content Provider | Semantic Scholar |
|---|---|
| Author | Konn, Cécile Fourré, Elise Jean-Baptiste, Philippe Donval, Jean-Pierre Guyader, Vivien Birot, Dominique Alix, Anne-Sophie Gaillot, Arnaud Perez, Florian Dapoigny, Arnaud Pelleter, Ewan Resing, Joseph A. Charlou, Jean-Luc Fouquet, Yves |
| Copyright Year | 2016 |
| Abstract | The study area is close to the Wallis and Futuna Islands in the French EEZ. It exists on the western boundary of the fastest tectonic area in the world at the junction of the Lau and North-Fiji basins. At this place, the unstable back-arc accommodates the plate motion in three ways: (i) the north Fiji transform fault, (ii) numerous unstable spreading ridges, and (iii) large areas of recent volcanic activity. This instability creates bountiful opportunity for hydrothermal discharge to occur. Based on geochemical (CH4, TDM, 3He) and geophysical (nephelometry) tracer surveys: (1) no hydrothermal activity could be found on the Futuna Spreading Center (FSC) which sets the western limit of hydrothermal activity; (2) four distinct hydrothermal active areas were identified: Kulo Lasi Caldera, Amanaki Volcano, Fatu Kapa and Tasi Tulo areas; (3) extensive and diverse hydrothermal manifestations were observed and especially a 2D distribution of the sources. At Kulo Lasi, our data and especially tracer ratios (CH4/3He ~ 50×106 and CH4/TDM ~ 4.5) reveal a transient CH4 input, with elevated levels of CH4 measured in 2010, that had vanished in 2011 (Futuna 2), most likely caused by an eruptive magmatic event. By contrast at Amanaki, vertical tracer profiles and tracer ratios point to typical seawater / basalt interactions. Fatu Kapa is characterized by a substantial spatial variability of the hydrothermal water column anomalies, most likely due to widespread focused and diffuse hydrothermal discharge in the area. In the Tasi Tulo zone, the hydrothermal signal is characterized by a total lack of turbidity, although other tracer anomalies are in the same range as in nearby Fatu Kapa. The background data set revealed the presence of a Mn and 3He chronic plume due to the extensive and cumulative venting over the entire area. To that respect, we believe that the joined domain composed of our active area and the nearby active area discovered in the East by Lupton et al... |
| Starting Page | 127 |
| Ending Page | 144 |
| Page Count | 18 |
| File Format | PDF HTM / HTML |
| DOI | 10.1016/j.dsr.2016.07.012 |
| Alternate Webpage(s) | https://archimer.ifremer.fr/doc/00347/45848/45505.pdf |
| Alternate Webpage(s) | https://doi.org/10.1016/j.dsr.2016.07.012 |
| Volume Number | 116 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
