 |
| Titel |
Hydrothermal Fluxes at the Turtle Pits Vent Site, southern MAR |
| VerfasserIn |
J. Köhler, M. Walter, C. Mertens, J. Sültenfuss, M. Rhein |
| Konferenz |
EGU General Assembly 2009
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250025523
|
|
|
|
|
|
| Zusammenfassung |
| The Turtle Pits vent fields are located in a north-south orientated rift valley at the
Mid-Atlantic Ridge (MAR) near 5oS. The site consists of three known hydrothermal fields:
Turtle Pits, Comfortless Cove, and Red Lion. Data collected during a Meteor cruise in May
2006 and a L‘ Atalante cruise in January 2008 are used to calculate the total emission of
volume, heat, and helium of the site. The data sets consist of vertical profiles and towed
transsects of temperature, salinity, and turbidity, as well as direct velocity measurements with
a lowered acoustic Doppler current profiler (LADCP) and water samples for Helium
isotope analysis. Vent fluid samples for noble gas analysis where taken with an
ROV.
The particle plume is confined to the rift valley since the depth of the valley exceeds the
rise height of the plume. Therefore the fluxes of heat and volume can be estimated from the
helium fluxes at the vent sites in comparison with the horizontal helium transport in the
valley. The comparison of the 3He concentration measured south of the hydrothermal
vents with the 3He signal north of the hydrothermal vents suggests a rather strong
northward flow. This is confirmed by the tide corrected velocities observed with
the LADCP during the Meteor cruise. The northward volume transport has been
calculated using the local bathymetry and tide corrected velocities from the Meteor
cruise. In combination with the 3He concentrations and an average 3He end member
concentration a flux of 900Â l/s is estimated, which corresponds to a heat flux of
450Â MW.
The rise height of the particle plume estimated from the turbidity data combined with the
known background stratification yields an estimate of the total flux of the hydrothermal vents
which is one order of magnitude lower. |
|
|
|
|
|
|