Station 1

As I write this blog, we are leaving Station 1. Most of us have had only a few hours of sleep in the last 24 hours but we know we are ready for what is coming. Station 1 was intense and full of surprises and taught us how we should run our operations. In a research cruise, the first station is always very stressful and a bit chaotic, as scientists try to get all types of samples they want and at the same time try to find a rhythm so that things go smoothly. So, it becomes a bit difficult. Lucky for us, the weather was great, so we had one less challenge. Here is a quick summary of what happened at Station 1.

One of the main goals of the expedition is to collect short cores from the ocean bottom. To do that, we need to make sure that our target locations have soft sediment. If we land our coring gear on a rock, it will simply break our equipment, which we absolutely want to avoid. So, about three nautical miles before we reached our Station 1, we started surveying the ocean bottom to locate soft sediments (lovingly called ‘mud’) so that we can deploy our coring device. The survey started a little after midnight, and we found the right kind of mud around 3 a.m.

We also wanted to collect water samples at different depths, so we put out a series of bottles and some sensors first. As these sensors are lowered, they send real-time temperature, salinity, and pressure data to us. This helps us decide where to collect our water samples. This operation took about 4–5 hours, and then we deployed the ‘Multicore,’ which is the main coring device for this expedition. This device has 8 empty tubes. The top of the tubes is capped, and the bottoms are open. Once it reaches the bottom, we let the whole device sink into the soft mud, and as it is pulled out, there are contraptions that close the open end at the bottom and hold the mud.
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This time we also had a camera installed on the Multicore so that we could see what the ocean bottom looks like. The Multicore operation is complicated, but we have experts who have extensive experience in running these operations, which we are heavily relying on. The deployment was successful — the Multicore went down to a depth of 3,500 m (over 2 miles), penetrated the sediments successfully, and then, as it was time to pull it out of the mud, we lost camera feed on one of the cameras. For the next couple of hours, as the Multicore was being pulled up through the water column, we did not know what went wrong, and if we would get any sediment in the coring tubes. The whole science team was on deck, waiting to see what happened as the Multicore was being pulled out of the water.

MIRACLE!

​The contraptions that close the tube bottoms and hold the mud had broken off on most tubes, yet the suction from the top cap was still holding the mud in the tube. Seems like the keepers of the ocean really want us to have mud. There were a lot of smiling faces as we did retrieve sediments, but also a lot of worried faces as the Multicore needed quite a bit of repair. We wanted to do another Multicore deployment at that location, but it was clear that it would take several hours to repair it. In these situations, scientists must decide whether they want to wait or rather conserve the time and move on. Since we could retrieve the most urgent samples from that one deployment, we decided to move on to the next station — which is three days away.

Author

Chandranath Basak