Wednesday 12 December 2012 See latest photos and updates at EllsworthLive
British team set to access and sample one of the last unexplored environments on
This week (12 December) a British team of scientists and engineers realise a 16 year
ambition to drill down through over 3 km of Antarctic ice into an ancient buried
lake. The team hopes to find signs of life in the water and clues to the Earth’s
past climate in the mud at the lake floor.
Using a high-pressure hot-water drill specially designed for the mission the 12-man
team will begin boring a hole through solid ice into Lake Ellsworth on the West Antarctic
Ice Sheet on Wednesday. It will be a race against time to keep the access borehole
open long enough to lower and raise two state-of-the-art instruments that will collect
water samples from the lake surface to the lake bed, and a core of mud from the lake
floor. The team can only keep the borehole open for 24 hours before it refreezes
to an unusable size, ultimately sealing the lake off again.
Precision engineering and technology are at the heart of this scientific experiment.
The hot-water drill, designed by British Antarctic Survey (BAS) engineers will take
around five days of continuous drilling through the ice to reach the lake. A titanium
probe, designed by a team at the National Oceanography Centre (NOC) will collect
water samples and data. A sediment corer developed by BAS with Austrian partners
will capture lake-bed mud samples.
The science team thinks that unique forms of microbial life could have evolved in
Lake Ellsworth’s extremely cold, pitch black and pristine environment and these may
have been isolated for up to a million years. If so the lake will provide clues
about the potential origin of and constraints for life on Earth, and shape scientific
thinking about the evolution of life on other planets. If no life is found this
would be an equally valuable result that indicates the limits of life on Earth.
Sediment samples (mud) from the lake are expected to yield important insight in to
the ancient history of the West Antarctic Ice Sheet and reveal vital secrets about
the Earth’s past climate. This will have implications also for our understanding
of future sea level rise.
It has taken the ‘Deep Field Team’ four weeks to set up living and working facilities
at the camp; to prepare and test the drill rig; and ensure final sterility measures
are in place before drilling commences.
The drilling mission is made up of four-stages:
1. Pump a high pressure jet of hot water slowly into the ice to create a borehole
that is around 40cm wide
2. Create a chamber in the ice (the size of a caravan) 300 metres below the surface,
fill with hot water, place a water pump inside to balance the pressure and prevent
lake water rushing back up the borehole when the lake is penetrated. This should
take around two days of constant drilling
3. Continue to drill the borehole for approximately three days more, going deep through
the ice and into the lake
4. Lower and raise the instruments to retrieve water and sediments samples for analysis
in UK laboratories – the team has just 24 hours to complete this stage before the
hole re-freezes to an unusable size
To protect Lake Ellsworth’s pristine environment and to ensure that uncontaminated
samples are brought back to the UK for analysis, space-industry-standard clean technology
has been used to sterilise every piece of equipment. This included a four-stage
chemical wash followed by full exposure to hydrogen peroxide vapour (HPV) during
the final assembly process. All equipment was transported from the UK in sterile
packaging and will be treated with HPV again on site. The water used for drilling
will undergo a four-stage filtration process, down to 0.1 microns, before being passed
under UV light and heated to 90 degrees C.
Lake Ellsworth Principal Investigator Martin Siegert from the University of Bristol
“This British mission is part of an international effort to discover and explore
subglacial lake environments. We are about to explore the unknown and I am very
excited that our mission will advance our scientific understanding of Antarctica’s
hidden world. Right now we are working round the clock in a cold, demanding and
extreme location – it’s testing our own personal endurance, but it is entirely worth
Lake Ellsworth Programme Manager and Expedition Leader Chris Hill from British Antarctic
“A major milestone last year was getting the bulk of the equipment and supplies to
the site - the logistical effort alone to get 100 tonnes of equipment to Lake Ellsworth
has been phenomenal. Now everything we’ve planned and prepared for is about to happen
and it’s tremendously exciting – if not a little nerve-racking!”
Lead Hot-Water Drilling Engineer Andy Tait from British Antarctic Survey said,
“This is a huge, but delicate operation. Although hot-water drilling technology
has been used extensively by scientists in the past, this is the first time we’ve
ever attempted to go through 3km of solid ice - this will be the deepest borehole
ever made this way. We’ve fired up the boilers to heat the water to 90°C. The water
pressure coming out of the hose will be around 2,000 PSI – 15 to 20 times more powerful
than the kind you wash your car with. It is the most effective way to obtain rapid,
clean access to Lake Ellsworth.”
The Lake Ellsworth Consortium is funded by the Natural Environment Research Council.
It features two of NERC’s Centres of Excellence – British Antarctic Survey and the
National Oceanography Centre – and nine UK universities.
Issued by the British Antarctic Survey Press Office on behalf of the Subglacial Lake
The unique five-metre long water sampling probe has over 3,000 individual components
and was designed and built by engineers at the National Oceanography Centre in Southampton.
Made of the highest grade of titanium to ensure maximum sterility and strength, it
has 24 water sampling bottles to collect water samples at different lake depths.
It will also capture the top layer of sediments at the lake-floor / water interface
where life could be living.
Scientists at British Antarctic Survey and Durham University, working in partnership
with Austrian business UWITEC, designed and built the sediment corer, which can extract
a core up to three metres long. The unique percussion-driven piston corer is strong
enough to penetrate even the most compacted glacial sediments to extract a core sample.
Finding life in a lake that could have been isolated from the rest of the biosphere
for up to a million years will reveal the potential origin of and constraints for
life on Earth, and may provide clues to the evolution of life on other extraterrestrial
environments. If no life is found in the lake this could be even more significant
because it will begin to define limits at which life can no longer exist on the planet.
Analysis of the sediments from the sediment corer will reveal clues to microbial
life and help scientists assess the present-day stability of the West Antarctic Ice
Sheet and the likely consequences for future sea-level rise. Water and sediments
samples will be analysed by consortium members in research institute and university
laboratories throughout the UK.