Ice Stories: Dispatches From Polar Scientists » submarine canyon http://icestories.exploratorium.edu/dispatches Mon, 15 Nov 2010 20:40:36 +0000 http://wordpress.org/?v=2.9.2 en hourly 1 Moving On http://icestories.exploratorium.edu/dispatches/moving-on/ http://icestories.exploratorium.edu/dispatches/moving-on/#comments Fri, 22 Jan 2010 20:41:41 +0000 Rob Dunbar http://icestories.exploratorium.edu/dispatches/?p=2174 JOIDES RESOLUTION, OFF THE COAST OF WILKES LAND, ANTARCTICA– So, guess what? We had to abandon our first drill hole, the one I wrote about yesterday. Turned out we had drilled into a massive body of sand, gravel, and big rocks...]]> Temperature +1C, wind 15 kts, 2 meter swells, 63 degrees 18 minutes South and 136 degrees 0 minutes E.

ABOARD THE JOIDES RESOLUTION, OFF THE COAST OF WILKES LAND, ANTARCTICA– So, guess what? We had to abandon our first drill hole, the one I wrote about yesterday. Turned out we had drilled into a massive body of sand, gravel, and big rocks. This came from the bulldozer effect of the ice on Antarctica. The force of the Ice Sheet as it grew to the edge of the Antarctic continental shelf scraped off all this rock and debris and bulldozed it into the deep sea – and think of a bulldozer with unlimited horsepower and a blade 2000 km wide. The power of ice to erode the hardest rock and move it great distances is unmatched by any other natural process on Earth. We just HAPPENED to be trying to drill where a deep sea canyon or channel was taking the heaviest stuff. This was unexpected from all of our pre-drill site survey work, and to be honest, very unlucky on our part – there aren’t that many channels of this type out here in the deep sea.

Our drill could only go 40 meters into the seafloor before it started to get stuck. But we described the core all night and learned some new things – like what kind of rock is under the ice. Since almost no rock sticks up above the ice, this is how we tell what is underneath. So every hole, even a short one like this one, has a story to tell.

We’ve since moved 84 nautical miles to place where we are sure there is no channel. The water is deeper but we are much more likely to achieve our main objective of seeing back into a time when Antarctica was ice free. So, we are all still excited and we are also trained as it was the first time the entire team of 30 scientists worked together with the staff and technicians on the ship to recover and describe the core.

Here are a few photos. The Albatrosses around the ship are amazing. They follow us everywhere.


Black-browed Albatross from the deck of the JR Expedition 318.

Expedition 318 scientists waiting for the first core.

Sakai-san, my roomate aboard the Joides Resolution Exp 318. He is an expert in Radiolarians, a really cool microsfossil.
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We’ve Got Core http://icestories.exploratorium.edu/dispatches/weve-got-core/ http://icestories.exploratorium.edu/dispatches/weve-got-core/#comments Thu, 21 Jan 2010 20:31:27 +0000 Rob Dunbar http://icestories.exploratorium.edu/dispatches/?p=2161 JOIDES RESOLUTION, OFF THE COAST OF WILKES LAND, ANTARCTICA– What an exciting day! After 2 days on site we have retrieved our first real core. The problem last night was that the seabed was so rocky and hard that it broke our bottommost drill pipes when we hit...]]> Temperature +3C, wind 5 kts, 1 meter swells, 63 degrees 50.5 minutes South and 138 degrees 49.4 minutes E

ABOARD THE JOIDES RESOLUTION, OFF THE COAST OF WILKES LAND, ANTARCTICA– What an exciting day! After 2 days on site we have retrieved our first real core. The problem last night was that the seabed was so rocky and hard that it broke our bottommost drill pipes when we hit. We had to trip (pull up) all 4 km of pipe (7 hours) and use a torch to cut off the bent and broken pieces. We then reassembled the whole thing and put a big rotary diamond bit on the end. Now we have core!


First core on the catwalk, Expedition 318.

It’s been all rock and gravel so far – a real surprise because we are in deep water far from shore. We think this is the top of a giant submarine fan, kind of like what you might get at the base of the Monterey submarine canyon. These canyons and channels act as conduits that carry big heavy rocks and lots of sand into the deep sea. But in this case the rocks and sands were carried to the edge of the continental shelf by ice! Well, we get 10 new meters of core every 3 hours or so now and so the work begins in earnest. Who know what lies beneath the rocks and gravel? We’ll find out soon – in this very first borehole drilled in this part of the ocean!


Christina Riesselman, Expedition 318 diatomist from Stanford, waits for the first sample.
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