Friday, November 9, 2007

More than 500 meters below sea floor!

Drilling is proceeding very well at the moment. We are already at 600 meters below seafloor, before we had time to celebrate that we have passed the landmark depth of 500 meters below sea floor. We don't know exactly where we are in time, because the paleontologists are behind in analyzing their samples due to the speed of drilling and the flow of samples coming in. We sedimentologists have seen some very interesting changes in the core over the past 2 days. We encountered several meter thick intervals of what we call mudstones. These are rocks made of very small rock particles. They often appear laminated with distinct layering. The rocks are now also more cemented and they dry out quickly, so we spray water on the surfaces to observe the textures. Also important is the absence of large rock fragments or clasts in the mudstones: it indicates there was not much ice around during the time of deposition. Interestingly, between the mudstones are beds with very large clasts: the record clast so far we found today is at least 42 cm in diameter, which means I am out of the competition .... my entry was 38 cm for the biggest clast contest.

While drilling is going well, the weather is not entirely cooperating. We haven't seen a plane come in from Chrischurch for the past 5 days as a large depression has the Ross Sea area in its grip. We have had a couple of snow storms and travel is permitted only in the very short pauzes between storms. The helo with core has come in from the drillsite, but the windows of fair weather are too short for trips further away, or trips that require sea ice travel. We haven't gotten any fresh fruit or vegetables for a while now and people and cargo are backed-up in Christchurch. Ha: the new weather forecast just got posted and it says inprovement will come in the next two days. Despite the snow and wind, it is actually quite warm. The -12C/+10F minimum windchill is nothing compared to what we had previously and it feels extremely pleasant now that we can expose our faces to the wind. Also: the first Skuas have arrived (Photo: C.B. Gunn). They typically arrive in early November. Skuas are scavenger birds that feed on anything from penguin eggs, dead penguin chicks, afterbirths of seals, and unfortunately the trash cans at McMurdo Station. They are also known to snatch food from peoples hands if they carry it outside. Still: it is quite nice to see some birds flying around. It is a sign of spring after all!
Another great experience was that the janitor in our dorm took us to the Discovery Hut and let us take a look inside yesterday. He is part of a select group of people with access to the keys of the huts. I have no time to post pictures now, but I promise to do that later. The Discovery Hut is in the picture posted previously here.. Check back in a few days for photos from inside the hut.

1 comment:

Anonymous said...

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