Checking out the Core
Well we have been here at our new site for a couple of days now, and we have already drilled about 500m.
This time we went straight for the RCB – and good thing too, because there was a bit of gravel within the first few meters, and as I said last time – that is not good for the APC drill. So we’ve been getting good stuff from this site.
There is some good lamination (dark and light layers) that are filled with diatoms. The core comes out of the seafloor in lengths that are 10m long. At least one sample – usually more, always goes to the micropaleotologists. Micropaleotologist look for diatoms, dinoflagellates or foraminifera (forams) using a microscope. These organisms can be used to date the age of the sediment in the core. How? Because over time, the organisms change – some go extinct while others evolve to something new. Kind of like the dinosaurs – if you find a dinosaur fossil – you know the surrounding sediment is 230-65 million years old (wow a big range) – i’m sure if I knew anything about dinosaurs I would be able to come up with a better example.
My friend Christina Riesselman studies diatoms at Stanford University and she gave me this video to show you all what diatoms look like under a microscope. These diatoms are not from this site, but represent a time period of about 3 million years ago. You can see that many pieces are broken – which makes here job a bit harder. What can you say – it’s hard to keep something in perfect condition for 3 million years.
I’ve also seen a lot of bioturbation in the core. Bioturbation is the displacement and mixing of particles by small animals that live in the sea floor (Similar to worms in a garden). Here you can see the told paths that the animals used that then became fossilzed over time (Pretty cool!)The blue end is the top, and other end is about 17cm deeper.
The water depth at this site is about 4000m deep. The weather has been unusually nice this week. Cloud cover, but calm. It’s been pretty warm also. Some others have seen a penguin that swam up to the boat, whales, and a seal. I always miss everything! Either I’m not fast enough, or I’m sleeping. So, so far, all I have seen lately are birds (which are cool too!).Check out the calm seas below
Check out our video report for week two! www.youtube.com/user/OceanLeadership