SOC press release, 29/7/03, Ref: 03/91

British oceanographers find 'smoking' submarine volcano
in the Indian Ocean

At over three thousand metres down in the north-west Indian Ocean, the Carlsberg Ridge is "probably the best ridge in the world". So say excited scientists from Southampton Oceanography Centre who have just found the first evidence of hydrothermal activity in this previously unexplored area of a volcanic mid-ocean ridge.

The team aboard the research ship RRS Charles Darwin made the discovery on Wednesday 23 July 2003 when they detected a huge plume of smoky water. The plume is at least 600 m thick, over 30 km wide and rises hundreds of metres above the lava-strewn, deep-sea floor.

Dr Bramley Murton, the scientist leading the research cruise, said: "The source of the plume is comparable to a suite of large power stations which continuously churns out vast amounts of heat and smoky water. The energy released could exceed 1000 megawatts."

Hydrothermal vents occur in areas of sea-floor spreading where volcanic eruptions create new sea floor or 'ocean crust'. As the molten rock cools and solidifies, water percolates down below the sea floor where it is superheated before gushing out from hot springs or vents at some 300 to 400°C. The smoky plume comes from iron-rich particles which solidify when the hot, mineral-laden fluids mix with the cold deep-ocean water.

Despite the total darkness and fact that hydrothermal vents are toxic to most living organisms, they typically teem with exotic, specially adapted life forms. Unlike most marine life, the communities of animals found at hydrothermal vents depend on special bacteria which use energy from the chemicals in the water to make organic matter.

Abundant hydrothermal vent life has already been discovered in the Atlantic and Pacific Oceans. In order to find out whether life is also thriving at this Indian Ocean vent, oceanographers hope to return to the Carlsberg Ridge in future with ISIS - SOC's new deep-diving ROV (remotely operated vehicle).

In the meantime, anyone with access to the Internet can follow the daily progress of the Carlsberg Ridge Cruise via SOC's Classroom@Sea website

Notes for editors:

The team of SOC oceanographers is taking part in a three-week cruise (18 July to 6 August 2003) aboard the NERC research ship, RRS Charles Darwin, to investigate the workings of the Carlsberg Ridge - a mid-ocean ridge situated in the northern Indian Ocean, between Africa and the Seychelles. This is the first time that the Carlsberg Ridge has been investigated scientifically.

The plume was detected with specialised MPAR (Miniature Autonomous Plume Recorder) technology provided through collaboration with the US National Oceanic and Atmospheric Administration's (NOAA) Pacific Marine Environmental Laboratory.

The scientists have named the area of hydrothermal activity the 'iGass site' - after the renowned British geologist, the late Professor Ian Gass FRS.

Dr Bramley Murton and Dr Rex Taylor (Southampton Oceanography Centre) are the co-principal investigators on the cruise. The research is funded by the Natural Environment Research Council (NERC) as part of the NERC Core Strategic Research Programme 'Seafloor Processes, Dynamism, Variability and Disturbance'.

ISIS is SOC's new deep-submergence ROV (remotely operated vehicle). Capable of diving to depths of 6500 m, ISIS is the UK's first ROV dedicated to deep-sea exploration and research.

Southampton Oceanography Centre is a joint venture between the University of Southampton and NERC. It is a centre of excellence in marine sciences, earth sciences and marine technology.

For further information:

Professor Chris German, Southampton Oceanography Centre, tel: 023 8059 6542, email: (before 1 August).

Dr Lindsay Parson, Southampton Oceanography Centre, tel: 023 8059 6541, email: (from 1 August).

Jackie Kelly, Press Officer, External Affairs, Southampton Oceanography Centre, tel: 023 8059 6170, email:

© CDSP 2003