Sunday, November 11, 2007

A Visit to the SMS Drill Site

Imagine driving along over sea ice in an oversnow vehicle for 2 hours - through magnificent scenery and vast emptiness,
and then suddenly, off in the distance, you see a flash of color and a white object sticking up out of the surface of the ice. You drive a bit further and the scene comes into view: it is a remote camp for 30 hearty souls, with a 90 ton drillrig, sitting atop 8 meters of ice. Cutting edge science research is being done right here in this remote, isolated spot. It is the ANDRILL Southern McMurdo Sound (SMS) Project Drill Site.

Why did they select this particular location?

Prior to site selection for a drill hole such as this, a great deal of effort went into understanding the regional geology. This SMS drillsite location was selected based on a combination of prior drilling projects, which revealed a great deal about the basin into which these sediments were being deposited, as well as seismic surveys, which told scientists a great deal about the geometry of the basin and stratigraphy (or layering) of rocks beneath the sea floor. Information from prior drilling projects also gave us information on age and depositional environments of some of these rocks. Based on these combined data, a the SMS Drill Site was selected to drill through sediments ranging from modern deposits back in time to perhaps as old as 34 million years. The site is approximately 30 miles from McMurdo, too great a distance to "commute" daily. So an entire camp was built for a team of 30 drillers and scientists, who work in two 12-hour shifts, 7 days per week, to get the drilling done while the sea ice is still sufficiently frozen. The target depth is 1,000 meters below the sea floor. We are currently at 635 meters, and going strong. What a thrill it was to see the drill and the camp in action!

To get to the drill site, we drove in Ford trucks, equipped with tracks rather than wheels. There is a flagged route out to the site, which took us along the whole length of the ice runway, on which a C-17 landed while we were driving parallel to it!
We then veered off toward the SMS site across the long expanse of sea ice, occasionally stopping to photograph some remarkable features and sights along the way. These bulging patches of blue ice are apparently melt pools which, when re-frozen, they expanded, resulting in mounds of blue ice dotting the otherwise snowy white sea ice surface.

After 2 hours, we had crossed a good distance of the sea ice covering McMurdo Sound, and were close to the glaciers flowing out from the Central Transantarctic Mountains. The views of the mountains were quite spectacular!

From a half hour out, we could see the drill rig poking up out of the ice, and the blue boxes which comprise most of the SMS living quarters. Upon our arrival, we were given a tour of the drill and all of its workings. The mast of the drill rig is 20 meters high!This massive structure, including the portions above and below the water, weighs 90 tons. Imagine that much weight sitting on the sea ice...

While I was there, a section of core was pulled up - from 620 m of depth. Four drillers were working together to operate the rig, mix the muds that are sent down into the hole to help bring up the core, and to person the many controls. When the core was brought up out of the hole, another team came to retrieve it, and immediately set to work recording information about the core - including a full scan of the core, a logging of all the fractures - both natural and drilling-induced, and physical property information. To learn more about the technology behind the drill rig, see

After our tour of the drill rig, we toured the living quarters for the 30 people who live at the drill site. The camp includes a kitchen, galley, bedrooms, equipment rooms, and a recreation room for the SMS Drilling Team. It was incredibly cozy and comfortable - I understood why people looked so happy out there!

As we drove back, blue sky was starting to emerge from behind the clouds. Mount Erebus finally came into view, as did the distant volcanic peaks from across McMurdo Sound. This all bodes well - as it gives me hope that the nice weather will continue, and I will fly out to join the Mackay Sea Valley Seismic Survey tomorrow. If all goes well, that is where I am headed. I will be out in the field until close to the end of November, so my blog will be quiet for awhile. Please check out the blogs of my colleagues! I will be back in touch in a couple of weeks.


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