It's a Wrap

We’ve just entered the port at Guaymas and are in the midst of cleaning and packing and tying up loose ends. Yesterday we did our “clean-up” on the seafloor, collecting some animals, deploying some gear for the next cruise, and picking up the last of our short-term thermocouple arrays. The two thermocouple arrays we recovered complete our sampling of very young chimneys and biofilms of known age. We recovered orange and white biofilm that grew over a 6-day period over a small vent in the southern part of the vent field.

While very little mineral material had accumulated, there was enough material present for there to be fairly stable temperatures at many of the thermocouples, and of 224°C at one of them. We’ve deployed a second array there in hopes that a chimney will grow during the next 15 days.

We also recovered our third short-term array from the Busted Mushroom site in the central part of the vent field. Unlike at the vent in the south, where the chimney hadn’t grown back in 6-days, here at Busted Mushroom the chimneys grow back very rapidly! With yesterday’s sample, we now have chimneys of know age and temperature that grew in 2, 3, and 5 days. (And we have one that grew in 4 days from 2003). While they do not look very different in the photos, the slightly older chimneys had more substantial walls and more volume that was at temperatures less than 120°C, so we think that the slightly older chimneys will have not only more microorganisms present, but more diversity.

After 2 days, three days, and five days

So while many of us leave today, Kristen and Meg will remain behind with Luke and the new Science Party that arrives tomorrow. In two weeks, they’ll go back and recover whatever has grown within our final two arrays during the past fifteen days, allowing us to view the colonization and succession within two different types of chimney environments. Stay tuned…

Lauri’s Guaymas Impressions:

17 November: Where did the time go? It is officially our last day at sea and the weather has allowed Alvin one last dive. Professor Brian Cox of the BBC accompanied Chief Scientist Anna-Louise Reysenbach and pilot Mark Spear aboard Alvin to capture some deep-sea footage and observe the sub’s operations.

Even with the rush to finish projects and pack up lab equipment, some of us made time to join Chief Engineer Jeff Little for a tour of Atlantis’ engine room.

It’s a spatially efficient combination of high tech controls and really big, noisy machinery that is divided into roughly three rooms: control, generators, and propulsion. Since the ship is ‘diesel-electric’, all of the power that controls everything from stateroom lights to deck equipment to the ship’s mobility is generated by an array of monster diesel engines.

In case you were wondering, all of that power consumes about 1500 gallons of diesel fuel per day when stationed at a dive site.


Alvin’s last dive for this cruise ended about 5 p.m., just in time for dinner!

Swimmer Dave forgot his robe and newspaper.

Like any vehicle operating in its environment, Alvin needs a bath now and then, and since this was the last dive, it was also bath time. So once the sub was emptied of it’s human cargo, everybody helped spend last moments of daylight scrubbing and rinsing.

We arrive in port late tonight after seven dives and ten days at sea. This has been a fun and productive cruise and I hope that you enjoyed following us as we explored the Guaymas basin hydrothermal vents! Keep checking this blog, as Meg and Kristen are still at sea and will retrieve the 2 thermocouple arrays that are still on the seafloor.

A Bit of Weather

The current motion of the ship and views of choppy seas are a stark contrast to the beautiful calm weather we experienced during the initial part of our cruise. It appears that a large high pressure system over Utah and Colorado has kicked up the winds in the Gulf of Mexico and we've seen sustained winds of around 25 knots since late last night. All that wind has stirred up the ocean and we are pitching and rolling in the 6-9 foot swells. Unfortunately, today's dive was canceled as this weather makes it unsafe to launch and recover Alvin (see previous dive post).
However, no time is wasted at sea and we've been busy catching up with our sample logs and lab work.

Sadly, our cruise is also rapidly coming to an end, with tomorrow being our last day at sea. Hopefully the seas will have calmed down so we can send Alvin down one last time for this expedition.

How, What, Where

This expedition to the Guaymas Basin is the third and final cruise in an effort to study the ecology of thermoacidophilic (heat and acid loving) microorganisms living in marine hydrothermal environments. Over the past year and a half, we have sampled several vent sites along the Mid-Atlantic Ridge, the Eastern Lau Spreading Center, and now the Guaymas Basin. Venturing to these contrasting vent sites has allowed us to study whether differences in the geology and geochemistry affect the occurance and distribution of thermoacidophilic microorganisms.

Much of our focus on thermoacidophiles at deep-sea hydrothermal vents has centered on an archaeal lineage known as the deep-sea hydrothermal vent Euryarchaeaota group-2 (DHVE2) as they were the first obligate acidophiles described from these environments. The first cultivated organism within the DHVE2, Aciduliprofundum boonei, was originally isolated from the Eastern Lau Spreading Center in 2006. Since then, we have cultured more representatives from the Mid-Atlantic Ridge, East Pacific Rise and again from Lau (see figure below). Cultivation of these new isolates continues to demonstrate the peptide scavenging lifestyle of the DHVE2 and is beginning to show some biogeographic patterns with respect to 16S rRNA gene diversity. Culture independent techniques, such as high-throughput pyrosequencing, are also beginning to show correlations between the type of vent feature and the presence of the DHVE2.

Neighbor joining tree of cultured representatives of the DHVE2 based on 1261 unambiguously aligned nucleotides of 16S rRNA gene sequences. Scale bar represents 10 substitutions per 100 nucleotides.

On our current cruise, we have been using quantitative-PCR (QPCR) to determine if the DHVE2 are present in vent deposits from the Guaymas Basin. Surprisingly, preliminary results have demonstrated the presence of these thermoacidophiles despite the higher pH of the Guaymas fluids. Below is a photo of a vent deposit collected during this cruise where the DHVE2 have been detected by QPCR.

Lauri’s Guaymas Impressions:

14 November: The Bridge is the tidiest place I’ve seen on Atlantis, although now I have a much better understanding of the term ‘ship shape’. It’s bright, shiny, and loaded with sophisticated technology surrounded by a panorama of windows. Chief Mate Peter Leonard recently explained the basics of the ship’s control and navigation systems to me as I stared in wonder. Thanks to an array different GPS technologies, some linked with the ship’s thruster controls, Atlantis can automatically remain within nine feet of a desired heading even in rough seas.

Computers and software have greatly enhanced navigation safety as well. Now most ocean going vessels are required to input their course and ship information into a system that makes the data available for other ships to see, thus enabling safe navigation especially in low visibility. But there is still some old-school equipment in use, my favorite being the wooden heading indicator from the original Atlantis called “the blocks”.

An Amazing Ride

Lauri's Guaymas Impressions:

13 November: Today I was given the opportunity to photograph Alvin's retrieval from the zodiac Avon so we could show you how Alvin is recovered after a dive. Words could not describe my excitement!

Since Alvin isn't designed to cruise along the water's surface, it needs to be towed a short distance back to Atlantis. This is a multi-step process that begins with two swimmers (Carl and Jim, today) and a driver (Jerry) racing a zodiac out about a half mile from the ship to the general area where Alvin is expected to surface. Once the sub is spotted we move closer so the swimmers can attach the sample basket stabilizer. This braces the big tray-like structure on Alvin's bow that carries all of the precious samples when the sub is lifted from the water.

As we get closer to Alvin, we all notice the strong smell of hydrocarbons and a light slick on the water's surface. Apparently crude oil seeps through the sediments on the Guaymas sea floor and is brought up in small amounts as Alvin ascends. This hydrothermally-formed oil is formed as we explained in the post "Holding Patterns". After the basket is secured, Alvin needs to have a sea anchor made ready for use. This parachute-like device acts as a brake and stabilizer for the sub when being towed, otherwise Alvin would not tow in a straight line. Once all that stuff is done, Jerry, Jim, and I speed back toward Atlantis, which is slowly steaming ahead to meet Alvin. After about 15 minutes, Alvin and Atlantis meet. Jim dives back in and helps Carl attach the towline and deploy the sea anchor.

Alvin then swings around and gets pulled into position under the huge crane known as the A- Frame. Once Carl and Jim have attached the massive lifting line, Alvin is raised to meet the two stabilizing dampers on the A Frame's teleleg.

A tail hook is then attached to the sub and the swimmers are free to show off their diving skills. Finally, the Avon's job is done and we return to the ship.

I felt incredibly free and yet vulnerable in the little zodiac as I watched the bulk and safety of Atlantis shrink into the distance. The vast seascape of rolling swell and chop provided me with a new perspective not just of the ship, but also of the abyss below and all the beauty and mystery within it.

Thanks again to everyone involved for this very special opportunity, especially Christine for sacrificing her training time. I would also like to thank Captain Colburn for his approval and the crew for letting me join them. It was truly a once in a lifetime experience.

Animals Abound

In addition to retrieving one of the thermocouple arrays, Dive 4557 brought a clump of tubeworms up from over 2000 meters below the ocean surface. This clump of worms the size of a soccer ball contained 18 small tubeworms and over 100 other smaller worms. We are interested in studying these creatures to understand how they thrive in such a variable and extreme environment that would be deadly to most animals living on the surface.

At the hydrothermal vents, the microbes that thrive on hydrogen sulfide provide the energy needed to support a prolific community of vent-associated animals. The quintessential vent animal is the tubeworm Riftia pachyptila. These animals have evolved to become completely dependent on symbiotic bacteria to provide them with nutrients. In fact, the worm is quite simplified and has a modified gut called a trophosome that is filled with cells that contain symbiotic bacteria. The worms simply need to supply the bacteria with hydrogen sulfide, nitrogen, and CO2 and the microbes use these simple building blocks to produce organic molecules that they share with their host. This teamwork strategy between the microbes and the tubeworm is highly successful allowing the worms to reach incredibly large sizes (some are over a meter long) and often these animals dominate areas around hydrothermal vents. Once you get over the grandeur of the tubeworm, you start to notice that there are a a lot of smaller creatures hanging around that are using similar strategies to survive in the deep ocean. Not surprisingly, there is a rich diversity of species in the vent communities that have figured out ways to either form direct partnerships with microbes or to live by eating the microbes or other animals.

Lauri's Guaymas Impressions:

12 November: Alvin's third dive was delayed for a few hours due to a technical issue, but eventually Mircea and Meg were sent on their way.

Pilot Mark's cool fisheye lens.

Up at the top lab, where Alvin and Atlantis communicate, I was surprised to hear how clearly voices travel through water, and with very little lag time.

We began production of the Best of Video DVD today, which will summarize the highlights of all the dives. There is some beautiful footage of the sea floor and what Fengping described as "massive dark lovely creatures shinning there, bubbling their story".

Alvin arrived at twilight, and brought with it many animal specimens such as tubeworms (and their hangers-on), more sulfides, and the thermalcouple array, which was coated with about eight inches of sulfide material and (hopefully) some microorganisms. The activity level really picks up in the evening, with processing continuing until well into the night.

Butterflies at Sea

Yesterday, we had another gorgeous day sailing in the Gulf of California. Dave Walter (pilot), Anna-Louise and Fengping headed down 2000 meters in Alvin and explored the southern and central areas of Guaymas Basin. The main goal of the dive was to collect vent deposits, scout the bottom for thick microbial mats, and sample some larger biological specimens- clams and tubeworms. The dive was both successful and historic, with Fengping becoming the first Chinese woman to dive below 750 meters. We are all very happy for her!

Visit this page for her personal account of the dive.

Lauri’s Guaymas Impressions:

11 November: Alvin’s second dive, which included history maker Fengping Wang, went off without a hitch. After watching the launch, we spent the rest of the morning and afternoon analyzing yesterday’s samples and photos, attending regular briefings and doing laundry. The weather is still fantastic and the seas calm. Richard, the mess attendant, gave me a tour of where they keep all the food… enough to feed 50+ people forup to six months.

I’ve seen so much amazing wildlife on this cruise. Last night groups of foot long squid were feeding next to the ship, sending flying fish skipping across the water. Bioluminescent creatures and microorganisms flash and dart in the swell, making the whitewater glow. The day before, a small hammerhead shark quickly toured the ship’s starboard side. And this evening a mass of beautiful yellow butterflies descended on the ship’s lights. Bring on the mermaids !

Dive Time

The morning began with a great sigh of relief as we obtained our official diplomatic clearance to dive. We wasted no time and started the dive, rolling Alvin out of its hanger just after breakfast. The sky was clear and sunny, seas were calm- all systems finally a “go”!

Bruce Strickrott, our Expedition Leader, piloted Alvin, with Meg Tivey and Paul Craddock aboard as scientific observers. Two observers, in addition to the pilot, are on each dive- the more experienced observer peers out the port-side porthole and the less experienced watches out the starboard porthole.

This was Paul Craddock’s first dive in Alvin!

The primary objective of this dive was to deploy the thermocouple array. This instrument allows us to study the microbial colonization of newly precipitated vent deposits- read more about this instrument and previous deployments at Lau Basin (will link to Lau blog specific post). The thermocouple array was successfully deployed at the “Busted Mushroom” site.

A current meter was also placed at the seafloor to help determine whether tidal currents influence the Guaymas hydrothermal vents. Two vent deposits were collected and brought on board for microbiological analyses and culturing.

Lauri's Guaymas Impressions:
10 November: Hooray, Alvin and crew got to dive today! After about 45 minutes of prep, the sub was hoisted into the water and detached from its lines.

Our afternoon was filled with last minute sampling set up and another science meeting, as well as yet another delicious lunch. The food is really spoiling me.

Alvin surfaced about 4:15p.m. And was greeted by a boat carrying swimmers and a towline. The sub's white body contrasted beautifully with the blue-green water. After hoisting Alvin and crew back on board, sulfide samples were quickly brought to the lab for analysis. And then we ate fresh mahi mahi for dinner.