Images of the Day
Deploying a borehole video camera
Real time video was very useful for inspecting the shape and size of the borehole, as well as peering through the lower borehole opening into the lake. The "mothership" camera was deployed on it's fiber optic and kevlar tether using a capstan winch for a controlled descent. Tyvek suits are used by operators on the deck to minimize any manmade contaminants; the tether ran through a UV germicidal collar just prior to entering the borehole, which is off to the left of the picture.
Another Good Day at the WISSARD Site
Good news from the WISSARD Field Camp!! Sensors on the hot water drill show a water pressure change, indicating that the borehole has connected with the lake. Verification awaits visual images from a down-borehole camera this evening. We are excited about the latest developments at the lake!
Drilling into Lake Whillans
The WISSARD team was thrilled when the traverse made it to the geographical location of Subglacial Lake Whillans on January 13th, 2013. The traverse crew, scientists, and drill team have been working in earnest, and the WISSARD project is getting close to reaching another milestone—actually reaching the lake itself—800m below the surface of the ice. Drilling operations have been ongoing for the past couple of days, and the drill team is in the final stages of drilling today, January 26th, 2013. To prepare for accessing the lake, the team changed nozzles to a wider spray (rather than concentrated jet used to make the borehole). The drill team will then drill the last 100 meters and break through more gently into the lake itself, making a wide/funnel shape in the bottom of the hole to avoid gushing drill water into the hole and stirring up sediments.
The team also did some work widening the hole at 100-110 meters, so they can make sure that the main borehole is well connected to the "keyhole" that contains the water-return pump. This way they can do a good job of controlling the depth/height of water in the borehole - (they want slightly less water pressure in the borehole than in the lake when they break in, so that a little lake water will come into the hole, vs. dumping drill water into the lake).
Today they are getting back down to the 700 meter mark, and will melt through to ~750 m. They will drill more slowly for the last 50 meters and should be through the ice (i.e. to Subglacial Lake Whillans) within 8 to 10 hours, baring no difficulties.
Image: Irina Alekhina. Head Driller Dennis Duling with the hose and drill nozzle at the test site in December 2012.
WISSARDS Reach Subglacial Lake Whillans
The WISSARD traverse team successfully reached the surface of Subglacial Lake Whillans the evening of January 13th after a historic trek of 628 miles across the Ross Ice Shelf. This is the next step as scientists begin their push to study one of the final frontiers on Earth, the subglacial Antarctic environment. The Whillans Ice Stream Subglacial Access Research Drilling (WISSARD ) project is a multidisciplinary scientific initiative focused on the aquatic ecosystem that lies beneath the Whillans Ice Stream.
Research is being conducted through integration of complementary science projects focused on Subglacial Lake Whillans (SLW), one of 300+ lakes buried below 800 meters (2,625 feet) of ice.
Scientists are interested in two research areas.
The first is the role of subglacial lakes in stabilizing or destabilizing the West Antarctic Ice Sheet—data collected from this project will be used to improve modeling of ice sheet dynamics. Samples of subglacial sediments and basal ice will provide an opportunity to study the history and evolution of Antarctic subglacial lakes and the ice sheet itself.
The second area involves looking for microbial life in the lake. The search for life in subglacial lakes is on the leading edge of scientific discovery, and is currently being pursed through three international efforts, including the American effort at Subglacial Lake Whillans.
Understanding the biodiversity hypothesized to be in the lake will provide fundamental information about microbial life that exists in dark and cold conditions, provide a measure of the limits of life on Earth and other icy worlds, and yield a better understanding of biochemical processes involved with elemental transformations on our planet.
WISSARD Geophysics in the Deep Field
Our traverse is making good progress toward Subglacial Lake Whillans, and our first wave of scientists heading to the deep field begins tomorrow! The WISSARD deep field geophysical team is traveling toward the lake first via a ski equipped LC-130 Hercules, and then onward via skidoo's to service and maintain 23 GPS stations which are used to measure vertical and horizontal ice movement on the Whillans Ice Stream. You can see the 23 stations in relation to Subglacial Lake Whillans in the map above, created by Matt Siegfried.
Matt Siegfried, one of the scientists on the geophysics team from Scripps has a fantastic blog where you can learn more: http://scrippsonice.wordpress.com/. We'll share more of this interesting project this week as the team begins their work on the ice... Travel safe Slawek, Matt, Grace, JT and Doug! See you at SLW!
The typical traverse set-up is 8 tractors and one Ground Penetrating Radar vehicle, which leads the way and checks for crevasses. The WISSARD traverse has 12 tractors and 1 GPR vehicle. Each tractor can pull up to 100,000 lbs on the steel skids. Fuel Badders (top left, in the image) weigh as much as 220,000 lbs. The WISSARD traverse is carrying 36,000 gallons of fuel, and should burn 24,000 to get to Subglacial Lake Whillans--using 40 gallons per mile to pull the heavy loads.
Image by Peyton Adkins
Map of Subglacial Lake Whillans Study Site
Map showing the Wissard Subglacial Lake Whillans Study site, 611 miles from McMurdo station where the scientists and support staff are preparing for science in the deep field.
Happy New Year from WISSARD
WISSARDS gathered to send off our equipment to Lake Whillans and ring in the New Year at WISSPOT (the WISSARD test site). Happy New Year from the WISSARD crew --- drillers, scientists, support and logistics personnel, and the EPO (education and outreach) team. We ended the year on a high note and look forward to an exciting 2013!
WISSARD Traverse leaves for Subglacial Lake Whillans
The WISSARD Traverse began its ~12 day journey to Subglacial Lake Whillans, today December 30th. WISSARDS gathered at the WISSARD test site to wish the traverse team well. The traverse travels an average of 7 miles an hour with 12 tractors towing wissard drill and science equipment. The traverse team hopes to reach the sheer zone, 20 miles from the WISSARD test site, on Day 1.
Happy Holidays from the WISSARD project! As the days get longer in the North, we are working hard down here on the ice, readying everything for the traverse and celebrating the holiday together.
Geothermal Probe Deployment
The geothermal probe was deployed down the test borehole in the McMurdo Ice Shelf overlying the Ross Sea. The probe successfully penetrated the sea floor to the depth of ~1.5 meters. Sediment was recovered (and sampled) from the top of the probe. It was a successful day at the site!
WISSARD clean access instrument testing
Today instrument testing continued at the WISSARD site. The IPSIE, our Instrumentation Package for Sub-Ice Exploration, sucessfully collected data and real-time video today when deployed through the borehole into the ocean under the Ross Ice Shelf. When fully assembled with all components, is it more than 40 feet in length.
Clean access is an important component of the WISSARD project, and all instruments are handled so we don't introduce contaminants into the pristine Antarctic subglacial environment.