Thursday, October 18, 2007

Arrival of the first ANDRILL Core

The ANDRILL core has arrived! It is a momentous day at the Crary Lab in McMurdo Station, Antarctica! The long awaited core has begun to be recovered! In the past few weeks, the drill rig has been assembled, and the riser has been set up. The drillers finally pulled up some drill string with core inside! It’s amazing to think about, really. These rocks and loose sediments have been peacefully perched below the seafloor for millions of year, holding their secrets deep within. Suddenly, the drill pokes through the surface, and penetrates through the different layers, bringing them up to the light of day. The frenzy begins!

These core of rock, newly brought to the surface, are immediately labeled and placed into boxes out on the drill site. At the designated time, a helicopter flies out from McMurdo to the drill site to retrieve the extracted core. Drillers carefully place the cores into the waiting helicopter.

The helicopter gently lifts off the ice surface at the drill site and flies, against the backdrop the setting sun. Eager onlookers in McMurdo gather at the helicopter pad watching for the helicopter. At first we can only hear it, reverberating from the ice surface and mountain tops. Then we see a light beaming across the sea ice, getting progressively larger as it approaches. We wait with tremendous anticipation, through the biting cold. The temperature has plummeted and the wind has picked up, giving us a windchill of minus 48 degrees F.

The helicopter comes into view and we fix our gaze on it. It feels as though this is the delivery of a life support unit, or a human heart arriving for a transplant. The helicopter approaches the landing pad as the recovery team hops in the truck to drive down to meet them. We all watch as the helicopter rotors slowly stop spinning. When the pilot steps out and gives the thumbs up, the truck for transporting the core from the helo pad to the Crary Lab speeds in. Carefully, the transfer is made, as the team clutches the 3 meters of core, careful not to drop or disturb it. A yellow bag travels with it - the contents of which are mysterious.

The team secures the core and the yellow bag, and then hops in the truck to carefully drive the core 100 m up the hill to the entrance to the Core Cutting Facility next to the Crary Lab. I have convinced myself that a patient is waiting in surgery, ready to receive new organs.

A small blue building next to the Crary Lab, with the ANDRILL emblem on the door, becomes the first stop for the newly delivered core.
The door swings open and the core curators rush the cores inside. After they unveil the core, they kindly invite my party (of 3 groupies) inside to come admire the core. I have an urge to touch it – and make a physical contact with this piece of earth history that has just been exhumed from the depths. But I resist. After all of the excitement, this is a very unceremonious viewing. All I can see a PVC tubes in a metal box. The core has not even been cut open yet to reveal the rock. This will all be done by the night shift.

The night shift will work through the night to cut the core, describe it, log it using a specially designed computer software program which allows curators to describe all aspects of the core, including a progressive interpretation of what the rocks show, and a variety of geological data on the core.

By morning, work on the core is well underway. There are layers of cross-bedded sandstone, volcanic rocks, and pebbly layers. There are also gaps in the core where styrofoam has been stuck in as a place holder. To the geologist’s eye, there are many stories to tell.

Immediately the different scientific teams get to work on the core. The curators curate and describe the core in great detail. Then the whole science team is invited in for a core tour, where scientists indicate which portions of the core they want samples of. This is a great opportunity to exchange initial impressions and observations about the core.

After desired samples are indicated, scientists get to work on their different disciplines.
Some work is done with the whole core, such as X-ray fluorescence, and porewater
geochemistry. Most other scientific work requires small samples. These include paleomagnetism, micropaleontology, stratigraphy, volcanology, and much more. It takes a few hours before the samples are prepared, but once the core starts arriving daily,there is a constant stream of work for the scientists, students, and teachers to do.

We are thrilled to have started the process and we look forward to daily deliveries of cores from the deep.

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