4th June 2011
We have just left our penultimate sampling site, Sars Seamount. Sars Seamount rises up dramatically from the abyssal seafloor, from 4000m up to just 500m below the sea surface. The flanks of the mountain are rugged: covered in pinnacles, ridges and steep cliffs. If it was on land it would be a popular site for extreme mountaineers and climbers. Strangely the top of Sars is completely flat, so flat in fact that we were able to trawl across the top collecting all sorts of interesting live animals and fossil remains.
One of the reasons I was so interested to come to Sars is that it has all these features that rise to different depths, so we can find a place to sample from shallow to deep whatever the wind direction. We spent nearly a week at Sars, and during that time we have taken photos, collected water, collected bathymetric data and sampled the seafloor fauna. The photographs have blown me away – they are crystal clear glimpses into another world – we are getting a four dimensional view of Sars. Not only can we see the bathymetry – we can see the animals that are living there today – and the fossil remains of animals that inhabited the seamount tens to hundreds of thousands of years ago. Even here, so far from any city we saw signs of human activity: a rope lying on the seafloor encrusted with seafloor animals – a reminder of our ability to impact all parts of the Earth – even deep below the sea surface.
Perhaps not surprising we saw and collected the most abundant and diverse samples at the shallower depths on the seamount. When we deploy equipment over the side we let it out at 30m per minute, so it can take a many hours to collect samples from deep sites. Despite the long times, and the lower recovery rates in deep water we worked hard to sample at 2000m water depth. In the end we were able to collect fossil coral remains from the peak of the seamount all the way down to 2000m. Together these samples will let us piece together information on the vertical structure of the water column here at Sars in the past, and compare it to the ocean currents that we have observed here today.
I am sad to be leaving Sars, it was a wonderful place to collect samples. But today we are moving to new adventures on the shelf of Cape Horn.
Wish us luck on our last week of sampling.
PS Happy Wedding Anniversary Mum and Dad!
Weather: temperature 32 ºF, winchill -4 ºF, windspeed about 30 knots, sunny intervals
|A 3D rendering of Sars Seamount prepared by Kathleen Gavahan and Shannon Hoy.|
|A fossil stylasterid coral from Sars Seamount (A. Margolin).|
|Early morning on the back deck, with Sebastian watching the dredge on its way up (R. Waller). |
|Stian, Mark and John retrieving one of the many dredges recovered from Sars (R. Waller).|