News from the Ridge-Crest: US GEOTRACES study of Sth EPR Hydrothermal Fluxes

 In late October, the RV Thomas G. Thompson set sail from

Manta,Ecuador, on the latest US leg of the international

GEOTRACES program with co-chief scientists Jim Moffett (USC)

and Chris German (WHOI) in charge: the East Pacific Zonal

Transect (EPZT).  Thus far, the team at sea have started

the transect beginning in ~100m water at the Peru Margin

and studying trace element and isotope distributions across

the high productivity upwelling zone near 12°S and the intense

oxygen minimum zone that extends offshore at these latitudes.  

In the second month of our cruise, we will be turning our

attention to the major hydrothermal plume, first identified

from He3/4 anomalies in the 1970s, that extends from the

super-fast spreading East Pacific Rise near 15°S for more

than 2000km across the South Pacific.  You can see

the track covered, and the distance still to be achieved

in EPZT Fig.A.






After 2 months at sea in total, Moffett, German and the EPZT team will sail into Papeete, Tahiti on Dec 22nd.