Dive, dive, dive…dive

15 May 2019

How many ROV dives can you fit into single day? This appears to have become the secondary research objective of this cruise as we continue to push the ROV team more and more as we work ISIS harder and harder. Today we managed not 2, not 3, but an unprecedented 4 dives in a 24-hour period.

A busy day for ROV Isis!

The first dive late last night continued our regular microprofiler surveys, moving the lander progressively closer to seep site. Or should I say seep sites – plural! As the experiment has progressed the area has become a real hive of activity. We’ve seen dozens of small CO2 gas seeps appear and disappear in the area, with a few long-lasting ones forming small pockmarks (craters in the sediment surface, formed by the bubbles). This dive also included the traditional gas and water sampling alongside sediment core collection for analyses back on board.

Microprofiler on the move…

The second dive was comparatively simply as ISIS collected one of the hydrophone walls from the site and brought it back on deck. The hydrophone wall has been recording noise around the seep. This gives us an important insight into manmade sounds in the North Sea – notably the ROV and James Cook itself, but also things like the laying of undersea cables far away. All these data help inform our analysis of bubble acoustics.

Hydrophone wall: wired for sound

The third dive was a classic switcheroo as one benthic chamber was swapped out for another to ensure a continuous time series of data throughout the experiment. And of course the dive was rounded off with more gas and water samples.

Swapping out the benthic chambers…

The fourth and final dive of the day saw the return of a fan favourite, as the newly resurrected bubble frame was sent back down (see the blog entry from 13 May). The team managed to salvage one of the camera housings and dipped it over the side of the boat to ensure it really is waterproof this time before risking our final camera in it. And as a great example of inter-team cooperation the AUV guys have lent us one of their cameras to use on the lander as well. We should know tomorrow whether the newly dubbed “Zombie Lander” has worked or not. Which means Thursday’s blog will either include amazing close ups of bubbles or a new author as I go into mourning…

As above, so below…

14 May 2019

Looks like our luck is back and stronger than ever as we round off another full day of surveying with some fascinating new finds. After spending the night away from the experimental site we returned this morning to redeploy our old favourite Freya, the Gavia AUV. Although initially reluctant to dive she eventually spent a few hours patrolling the site collecting sidescan sonar and sub-bottom data.

Launch of the AUV Gavia, aka Freya, with the Goldeneye platform on the horizon

The sub-bottom data is created by sending out a series of high frequency sound waves into the seabed and observing the strength of the sound waves reflected back, like sonar. However, unlike sonar, the sound waves actually travel into the underlying sediment and reflect off the interior layers in the sediment, allowing us to see what is under the surface. Today’s sub-bottom survey was particularly exciting as it revealed the exact position of the gas pipe we’ve been using in the experiment, and shows our gas escaping from it just as we planned.

Sub-bottom profile data showing the position of the pipe (black dot) and – to the trained eye – the gas escape above it (the fuzzy bit!)

That’s not the only thing going on today though – the sensors team is hard at work processing the data from their landers. Despite the rate of bubble release being relatively low, less than 30ml/min, they’re already seeing distinct changes in the chemical properties of the water and the sediment in response. We’re so pleased with these results we’ve decided to roll onto the next phase of the experiment, upping the flow of CO2 from the tank to increase the rate of bubble release. Stay tuned to find out what happens over the next few days…

PS – How cool is this? Footage from the ROV of CO2 gas bubbling out of the seafloor sediments at the experiment site!

Almost as cool as the STEMM-CCS beanie hats that the team is sporting today…

Everyone is working hard – clockwise from top left: Isabella, Rudi, Paul & Chris, and Dirk. Team beanie hats abound today!

Small hole, big problem…

13 May 2019

Well, it was bound to happen eventually… we’ve used up more than our fair share of good luck these last couple weeks and have finally suffered our first failure. And of course it had to be something I (Ben) was in charge of: the bubble frame which was put in place on the seabed late last night. Equipped with two underwater cameras and an illuminated back panel  (against which to see the bubbles rising) it was supposed to give us a glorious close-up view of our bubbles.

Unfortunately, on its return to the deck of the ship the waterproof casing that houses one of the cameras immediately started pouring out water – always a bad sign. What small iota of hope I had for the second camera being safe was sadly shattered when the first clasp on the housing was released and the insides instantly shot out along with a nice spray of water. At this time, I can report both battery packs and one camera are dead, with the other in a critical condition (i.e. in a bag of rice).

Arghh. ARGGH. Soaked cameras…not a good outcome!

A post-mortem of the camera housings revealed a small manufacturing default just beneath the lens of both sets which had allowed water to slowly seep in over time and flood the camera. Just goes to show that sometimes you can do everything right but things still go wrong.

Kev and Rob perform an engineering post mortem

Of course we’re not ones to cry over spilled milk on the James Cook, we’re problem solvers here. As the great hotel reviewer Bear Grylls says “improvise, adapt, survive.” With a full understanding of what went wrong, Rob is already hard at work fixing the housings whilst backup cameras are being prepared. Odds are that the bubble frame will be back in the water before the week is out!

Steering the blog away from my problems, everything else has been going amazingly well. Gas and water samples are continuing to be collected and analysed and the benthic chamber has been redeployed. We’ll be moving off site soon so the RV Poseidon can carry out some water column surveys using CTD (conductivity, temperature, depth – the three basic measurements of seawater properties) before we all leave the area to give the hydrophone walls some “quiet time” with the bubbles.

Kate hard at work analysing water samples in the cold lab. Nice hat, Kate!

Laughing…or crying? Our blog author Ben, who has not had the best day at sea today.

Catching bubbles

12 May 2019

It’s been our first day of post gas release surveying and boy, has it been a busy one! ISIS worked throughout the night, monitoring the injection gas pressure at the CO2 tank and carrying out a transect of the site using our micro-profiler. This small lander takes various measurements from the underlying sediment and once analysed will reveal exactly how the release of CO2 gas has affected the surrounding sediment.

Of course we don’t just want to know how the sediment changes but also how the water and even the gas itself reacts. Thankfully to that end we have Anita on board who’s been using the ROV to collect water and gas samples. The gas samples are by far the most entertaining as ISIS attempts to use an inverted funnel above the seep and capture each bubble as it escapes – not the easiest task!

Stay tuned tomorrow as we get our first post-release data and some up close visuals of the bubbles.

Anita closely monitors the work of ROV Isis via the screens in the control van on the ship

This is how you catch bubbles: with a robotic arm and an inverted funnel!

Once the gas samples are back on board the ship, Anita carries out chemical analyses in the wet lab

Bubbles!

11 May 2019

Huge news from the James Cook today as we kick off the controlled release experiment in style and finally see our first real bubbles!

The CO2 tank was linked up with the pipeline late last night by the ROV. After some initial pipe testing this morning we were confident enough to slowly pressurise the pipe and drive out any water that may have been stuck inside. Then, with bated breath, we increased the pressure and stared eagerly at the flow gauges and EK60 data. The flow gauges would let us know as soon as gas started flowing out of the tank, through the pipe and into the sediment, whilst the EK60 – a type of sonar – would let us know the moment any gas escaped into the water column. This was a moment 4-5 years in the making!

Within 10 minutes the flow gauge began to move and simultaneously a bright spike appeared on the EK60 data – you couldn’t ask for a better sign. ISIS quickly headed off to the release site to scout out the newly-formed seep. The ROV control van quickly filled with scientists desperate to be the first to spot the seep. And of course who better to first see bubbles than our project leader Doug Connelly!

Waiting for bubbles…a tense moment for project leader Doug Connelly

There they are! First sighting of CO2 bubbles at the seafloor

To say the team was excited and maybe a little relieved would be an understatement (just look at Chris!). This was a huge undertaking and there were a lot of doubters out there but we did it! And I’m definitely using the royal “we” here as credit for the successful gas release goes almost entirely to our engineering team of Hannah, Rob and Kev. They have been working tirelessly to pull off this incredible feat the entire length of this expedition, not to mention the months of hard work they put into building the CO2 tank, and the years they put into designing it. So a massive thank you to them! Enjoy a well-deserved break!

Chris – are you excited? Er, just a bit.

Smiles all round from Hannah and co.

However, for the rest of us there’s no rest for the wicked – and we’re straight into planning the next round of deployments. After all, this whole project is about testing methods of detecting CO2 escape, and that now we finally one (albeit a fake one!), the fun can really begin!

Despite today’s huge achievement, the job isn’t over yet – Kev and Rob (our engineering masterminds) have to stay focused to make sure the equipment continues to perform as it should…

…and of course, for cruise leaders Doug and Chris the planning continues apace

Two’s company…

9 May 2019

Looks like this blog has really caught on. So much so that the German research ship Poseidon has turned up to have a look around. I can’t take all the credit though as this date has been part of the plan all along. The controlled release experiment is so ambitious we actually need two research ships to get everything done on time. Our counterparts on the Poseidon will be doing a large part of the water column chemistry and collecting long sediment cores to better understand the area before and after the gas starts bubbling. The team on board are also posting regular updates of their activities – you can read the English version here.

Ahoy there! The RV Poseidon is spotted on the horizon, primed and ready to play her part in the controlled release experiment

The team on board RV Poseidon will make crucial water column measurements and observations in the area surrounding the experimental site during the gas release, and then undertake the final comprehensive survey of the site once everything is finished and all the equipment has been removed.

But back to the James Cook where the real action is happening. Everyone on board has really found their rhythm now as we manage to get ahead of schedule today despite another busy roster. We arrived back at Aberdeen early this morning for a quick ship transfer of equipment (and onions) before speeding back to site and carrying out two more ROV dives. These involved swapping out one baseline benthic lander with another to ensure a continuous sweep of data, and depositing a second hydrophone wall (two really is better than one today!).

Loading the benthic boundary lander onto the ROV, ready for deployment at the seafloor

More action in the ROV control van…

…And full concentration required from Chris, Paul and Isabella!

Tomorrow is the big day as we will connect the gas tank with the pipeline and enter the final stages of release preparation…stay tuned!

Another day, another dive

8 May 2019

We’re fully in the swing of things now having spent another full day deploying equipment on the seabed. The teams are definitely getting their money’s worth out of our ISIS ROV, keeping it busy in the water for over 10 hours across 2 dives today.

Isis has been busy today…

All eyes on the multiple screens on the ROV control van back on the ship

Today’s first dive revolved around the micro-profiler. This device analyses the chemistry of the sediment below it by slowly inserting glass micro-sensors into the sand on the seafloor. This only takes around 45 minutes, which means ISIS can wait for the profile to be finished before moving it somewhere else and repeating the process. This allows us to learn about the sediment chemistry along a transect line leading away from the future release site.

The microprofiler in place on the seafloor, surrounded by optodes and with the hydrophone wall in the background

However, even though the micro-profiler will provide a comprehensive survey all by itself, it’s  still not enough for us! So we rounded off the day deploying the benthic chamber to collect even more background data.

So ends another jam-packed day on the James Cook. Thankfully for the ROV team, tomorrow should be a little easier as we’ll be quickly swinging back past Aberdeen to pick up some last minute parts before returning to the experimental site.

A hard day’s work

7 May 2019

We’re back on site and hard at work to make up for our time away. The ROV has been deployed not once, not twice, but three times – each time ferrying down a different collection of sensors and equipment.

First thing this morning the ROV Isis collected some push cores (small tubes of sediment from the uppermost part of the seafloor) and carried down the sediment optodes. These small spike-like sensors were slowly inserted into the seafloor sediments, where they’ll stay for the next few days to record the pH.

Veerle and the team monitor progress at the seafloor via the monitors in the ROV control van

Technical crew also keep an eye on progress

Straight after lunch the hydrophone wall was loaded onto Isis. As its name suggests, this apparatus contains 5 hydrophones – a type of underwater microphone – arranged in an X shape on a frame that will sit at the seafloor. These hydrophones will (we hope!) eventually record the sound of gas escaping from the seabed, giving us a measurement of gas flux.

Wall of sound: this is the hydrophone wall, specially designed and built to detect bubbles in the water column, in position on the seafloor. Exciting times!

Last but not least today the baseline baseline boundary lander was deployed. This impressive lander will conduct a pre-programmed time-series sampling of the water at the seafloor over the next 48 hours. This will provide us with a wealth of information about the background chemistry of the area before we begin the controlled release experiment.

And with that, the work for the day is finished and the ROV team take a well-deserved break. We’ll be similarly busy day tomorrow so stay tuned!

A musical interlude

6 May 2019

We’re officially on the 2nd leg of the expedition now as RRS James Cook set sail from Aberdeen earlier today. With any other expedition you’d probably find a certain reluctancy to leave port (especially one like Aberdeen) but here its quite the opposite. Everyone is eager to get back to work and finally start making some bubbles!

And of course what better way to whet everyone’s appetite than an all-hands science meeting to plan the exact position of our landers on the seabed. Again, for any other expedition the thrill of getting to use Chris’ war room style map would be more than enough… but not for us. We managed to combine the session with a test of the James Cook’s intercom system, meaning (questionable) pop music was blaring out of the ship’s speakers throughout. While this made hearing everyone a little difficult, it certainly made for a unique experience – and after all that’s what we’re all about here at STEMM-CCS.

It’s an early night for everyone today as we move into 24 hour operations and begin our first ROV deployment at 7am tomorrow!

Out with the old, in with the new

5 May 2019

The James Cook is in port today as we finalise preparations for the 2nd leg of the expedition. New pieces of equipment, including our underwater camera frame and sediment optodes (instruments that measure things like oxygen in the seafloor sediment), are being loaded on board ready for the controlled release experiment. But more important than the new pieces of kit are the new scientists coming with them… Dirk, Isabelle, Jonas and Paul were barely on the ship for 5 minutes before taking part in an ‘all hands’ meeting and getting caught up on the events of the first leg (as if they hadn’t been reading the blog!). Paul even received a crash course in seismic processing.

All hand science meeting: preparing for the start of the controlled release experiment

Chris and Doug brief some of the new arrivals

Paul (right) receives a crash course in seismic processing

Sadly, with such a big team involved in this project, new scientists coming aboard means some people have to leave….so goodbye to Estelle, Jianghui, Jon, Mark and Michael – thanks for all your help!

Homeward-bound for some of the team!

Those of us remaining on the ship for the next leg are making the most of our time in Aberdeen as we set sail again tomorrow and won’t be on land again until the end of the month!