Volcanos, vents, and creatures of the deep, oh my (Part 2)
The ROV Jason Teams's most memorable dives
The Jason Team knows regions of the ocean floor like other people might know paths in their favorite mountain ranges. They've spent hundreds of hours in the ROV's control van where a bank of screens displays the deep sea from all angles. They've driven the vehicle over live volcanos, navigated to new hydrothermal vent fields, and encountered animals of all sizes. We've seen our share of breathtaking underwater landscapes during the PROTATAX23 dives, and we've heard adventure stories from other Jason expeditions. Here is a selection.
Other beings
When diving, Jason encounters sea life at every depth. On the descent, especially after dark, the surface ocean teems with gelatinous and soft-bodied animals: squid and jellyfish undulating in and out of view as the vehicle glides towards the bottom. The seafloor has a cast of characters: silvery rattail fish trailing the vehicle, spider crabs climbing into the basket, Dumbo octopuses making appearances. And of course, the worms, mollusks, and bacterial mats that thrive near vent systems.
Sometimes studying this sea life is the object of the dive-other times the life appears to be studying Jason.
"In New Zealand, just a few weeks ago, I saw a red squid maybe ten feet long," said Jason Team member Hugh Popenoe. "It was on our ascent, so the van was empty and no one saw it but Akel [Kevis-Sterling] and me. It approached one of the lights and grabbed it, realized it wasn't edible and took off. We didn't get a second look at it. I had to go back into our video recordings to make sure I'd really seen it."
"I've seen it all, glamorous Dumbo octopuses, angler fish with their light and big old teeth," said Kevis Sterling. "We've had sharks aggressively try to intimidate Jason. They come right up to the vehicle and bump into it."
But perhaps the most memorable sight of deep-sea life that many members of the Jason Team remember involves both seismic activity and creatures. If you've followed this team for any amount of time, you might have guessed it: Shrimpquake at Mid-Cayman rise.
Popenoe was in the Jason control van when it happened. "We were on the bottom at a vent that was covered in shrimp and then all the sudden all the shrimp pop up, and a few seconds later there was a sound like the thrusters of the ship being turned on. The geological wave from an earthquake hit the shrimp and then the water wave hit the ship."
As sense of danger
Entering the deep sea at all is a perilous endeavor. Jason must be capable of operating under crushing pressure and any sensor and instrument that dives with it must be too. Anytime the vehicle encounters an erupting volcano, a vent system full of incomprehensibly hot water and tall pillars, or any sea life, the team must take extra care. Any of these things could damage the vehicle.
"[Diving during the West Mata eruption] was one of the scariest moments," Tito said. "We had a couple events where the vehicle got covered in tetra and rock. We had to use the slurp to vacuum it off for hours before it was light enough to return to the surface."
Working in the taller vent systems requires careful piloting, added Tito. "Everything is so ethereal, the diffuse flow, the shimmering in front of the worms and such, the hot black smoke coming out and making visibility awful in some directions, but there is a sense of danger because you could melt the tether."
Dangerous or not, some of these environments offer a thrill that team members can only compare to science fiction. At one of Jason's most frequent dive sites, 9°50' North on the East Pacific Rise, there is a small valley that is about 100 feet wide, or less.
"We were flying Jason through that valley," said Popenoe, "And the walls and bottom are all black basalt, and it's so narrow that it feels like we're flying quickly. It's like cruising in those channels in Star Wars, when they go to blow up the Death Star."
Humans on the high seas
Even with all these adventure stories, for many members of the Jason Team, it's an encounter unrelated to science that encapsulates their work at sea. Several members of the Jason Team on PROTATAX23 were also on an expedition to the Mediterranean in 2011. They were studying hypersaline areas in the Mediterranean Sea that behave like independent bodies of water, with their own shorelines and waves.
"Jason would descend and reach the brine pool and we couldn't go any deeper," said Kevis Sterling. "It was like hitting the floor. We couldn't get Jason through."
Early in that voyage, WHOI ship R/V Atlantis, responded to a distress symbol from a disabled fishing boat and took 93 Egyptian refugees aboard.
"Some of the people had cell phones and some didn't have shoes," recalls Popenoe. "They were on a journey, trying to find a better life for themselves, and it's one of my strongest memories of doing Jason work, although it's not science related."
- Hannah Piecuch
This NDSF blog series will follow the PROTATAX23 expedition to Axial Seamount, covering the science and scientists at sea, and the ROV Jason operations that make it possible. PROTATAX23 is funded by the National Science Foundation (NSF OCE Award #1947776).