In the morning of Nov. 29. the Atlantis reaches Manzanillo; the pilot boat has just dropped the pilot who will navigate us to safe anchorage in the busy harbor, the largest on Mexico’s Pacific coast. The scenery no longer bears any resemblance to the deserts of Sonora and Baja California; Manzanillo is seriously tropical.

Everyone is gazing at the town, familiar to many science crew members as the base of the 2016 Guaymas cruise. A word cloud of these cruise participants’ thoughts would certainly feature various beverages, the pleasure of walking on land, exploring the town, and finally overloaded taxis to the airport, and the long journey home. This blogger will spend much of the day in Manzanillo, running errands and sending samples off to Mexican collaborators via Fedex. Others will simply enjoy a leisurely walk and some shopping. Manzanillo has decades of experience in entertaining tourists!

The official end-of-cruise party takes place at the Hotel Colonial, an atmospheric and old-fashioned place near the harbor. Their margaritas are perhaps a little too sweet, but the grilled shrimp and the shrimp ceviche [subtly flavored with oregano, not cilantro] are excellent! And the company is great too; some Mexican friends and aficionados of WHOI live in town and help the science party to celebrate.

Instead of questionable pictures, we post this lovely shot of “Team Crustacean”, Javier and Thorsten. Their collaboration on bacterial epibionts growing on vent crabs will perhaps lead to a post-cruise meeting in Baja California…

Tomorrow, most science crew members will head to the airport, carrying lots of samples, fresh data, and many good memories. While the 2016 cruise was beset by customs and logistics problems, the expedition-style planning and cruise arrangement has avoided these pitfalls, and ensured a generally smooth and successful cruise.  A big “Thank you” to the Atlantis crew, the Alvin and Sentry groups who kept everything together and did a wonderful job in making this a great cruise!

— END OF BLOG —

Thank you for visiting and following, and for sharing this expedition with everyone who is interested!

Andreas Teske, UNC -Chapel Hill, teske@email.unc.edu

Today’s blog is really not glamorous. The theme of the day is boxes, our own boxes and those of the next science party, a training cruise for aspiring seagoing young investigators co-led by Dan Fornari. (It is amazing what they teach nowadays, mobilizing the entire costly apparatus of Atlantis and Alvin!) The equipment boxes of this trainee party need to migrate out from the upper deck container that housed them for over two weeks, and move into the main lab, a daunting prospect for small car-sized gear. The Atlantis crew and crane ride to the rescue in time before self-inflicted injuries can be incurred.  In turn, we begin to move our boxes into the container and fill it halfway.

The only problem is, the trainee boxes occupy the space that is usually reserved for the tennis table; no games for the time being… their silent presence speaks of the transitory character of the cruise experience. We are winding this adventure down, while others are setting out in anticipation, perhaps even equipped with a visa de cooperante.

Most of the afternoon is spent packing our own boxes, which seem to have multiplied while nobody was looking, and then cleaning the labs. The ideal is to leave no trace, no dirt, no mystery chemicals, nothing that could infringe on the scientific success of the next cruise party. It also means leaving no cores! The cold room has accumulated many of these that have remained unclaimed. Gunter calls for a core auction after dinner. Here we see him appraising Guaymas sediment cores, explaining their extraordinary biogeochemical potential and extolling the fantastic sampling sites where they are from. This or that core could redirect an entire scientific career! Mandy is looking sceptical but in the end takes some cores. Gunter also adopts some. I take the remainders at a reduced price, just like at Ocean State Job Lot. We do not want to throw them away; factoring in the daily costs of Atlantis and Alvin, obtaining one pound of Guaymas mud costs at least 1000 dollars.

While the final cores are divided up, the internet keeps getting better as the ship moves closer to shore. Update announcements for obscure programs begin to pop open on every screen. The fangs and tentacles of the web are reaching out… this means checking email soon, a much-dreaded prospect.

Shipboard life continues during and after the Alvin dives. Rebecca maintains a normal schedule and is at work at her paintings during the day when most lab inhabitants catch up on their sleep. After a series of Beggiatoa- influenced works that reflect the orange/yellow/white palette and the irregular outlines of colorful microbial mats, she is in a blue “archaeal” phase that demands her full concentration.

The daylight agrees well with Dir deBeer, here at his microprofiling station where he has determined the chemical gradients in numerous microbial mat cores and reference cores. These cores were subsequently frozen away at -80C for high-resolution spatial and structural analysis of organic compounds at the Hinrichs lab at Bremen University. The goal is to superimpose and correlate microprofiler gradients that delineate the habitat characteristics, and molecular structures, which reflect the microbial biomass of dominant populations in the gradient habitat.

Complementary work in high-resolution organic matter structural analysis [in larger cm-thick sediment layers, without the spatial component on microsensor scale] will take place at Oldenburg University, in a collaboration of several groups at the Institute for the Chemistry and Biology of the Marine Environment. Here Thorsten Brinkhoff is slicing a sediment core for the Oldenburg group.

In the same lab, UNC graduate student Chris Chambers, the bench neighbor of MPI student Marit van Erk, is sampling sediment cores for his biogeochemical project, determining sulfate and sulfide gradients of sediments; these data will be used to assess seawater inmixing into the hydrothermal sediments, but they will also provide biogeochemical characterizations for the WHOI project, cultivations and activities of hydrocarbon-degrading fungi in Guaymas Basin sediments. Next to bacteria and archaea, fungi – generally single-celled microscopic forms – belong to the diverse group of organisms that degrade hydrocarbons in nature.

On the morning of Nov. 27, after the last Alvin dive, the long-anticipated T-Shirt sale of the Alvin and Sentry groups is finally starting. The T-Shirts are customized and printed at the Howlingbird Shop in Falmouth, MA, and the latest Alvin- and Sentry-themed designs are sold exclusively here on the ship for the benefit of your hard-working Alvin and Sentry teams. Get your Christmas presents now!

Sentry rests after many all-night missions, after surpassing all expectations; this smart AUV has sniffed out the methane plumes, redox signals and thermal anomalies that define the hydrothermal plumes rising from the vents almost 100 meters into the water column. In doing so we have now 3D reconstructions of the major hydrothermal plumes across the southern Guaymas vent field. The major vents, for example Northern Cathedral and Big Pagoda, have their own very localized plumes that emerge from a single source. Other hydrothermal areas have a more diffuse, almost communal plume that emerges from many smaller sources, for example in the Mat Mound Massif.

Zac Berkovitz is leading the Sentry team on this cruise; they have all done a fabulous job and used Sentry to full capacity: chemical and thermal sensing; bottom photo surveys, bathymetry, and subbottom seismics, all wrapped into one package. There is nothing like Sentry! To top it off,  Zac is now rewriting detailed instructions for the Sentry data package – a guide to Sentry-generated data files and the programs that are required to open and process them. It is almost heretical to say, especially for an Alvin aficionado, but it would be possible to run a very successful survey cruise in the Gulf of California only with Sentry and the occasional water column sampling trip by CTD.

Now, back to work! This blog page is uploaded in the morning of the 28th. We have one more day in the lab, to be used for packing and stowing, before arrival in Manzanillo in the morning of the 29th.

The last dive is again a PIT dive, Anthony Tarantino as driving instructor and Todd Litke as trainee. But who is the science observer? Since this cruise is shorter than usual, it will not be possible to get all Alvin novices into the sub. The person with the strongest claim would be Virginia Edgcomb, associate scientist at WHOI and experienced seagoing microbial oceanographer; she is also a PI on a NSF project attached to this cruise. Yet, there are three equally deserving young scientists – Marit van Erk, Viola Krukenberg and Vivian Mara – who should all have the opportunity. Now human generosity and the Greek gods intervene in the most miraculous fashion. Virginia Edgcomb gives up her dive, since she would not enjoy it as much as one of the younger scientists would. Thus, Virginia and your blogger come up with a design for divine intervention. Three Alvin cups are prepared by yours truly and shrunk during dive 5000, showing an Riftia bouquet, an octopus and a microbial mat. The cups are wrapped and each candidate chooses one. The microbial mat wins. Now, Poseidon must have reached up from the ocean and intervened in favor of a daughter of Hellas: Vivian draws the microbial mat!

Vivian and Virginia graciously pose for the paparazzi. Virginia Edgcomb is Vivian’s postdoctoral advisor at WHOI; Vivian comes originally from the beautiful Island of Crete, birthplace of Zeus, and represents Greece on the roster of Alvin dives, perhaps for the first time in Alvin history.

Vivian and her pilots loose no time in collecting a last haul of hydrothermal sediment cores for the science crew. This collection is important, because these cores can be worked up without having the clock of the next Alvin dive already ticking. Every biogeochemistry crew on the Atlantis appreciates this conclusion to an expedition..

Fortunately, Vivian and her team also have time for a visit at Northern Cathedral Hill to admire the Riftia gardens, one last time. It is like being admitted to a very exclusive National Park that allows only a few dozen people in, even in busy years.  The view through the porthole and its massive window, and past the robot arm, also illustrates the distance; the view is not immediate but necessarily constrained; human observers can reach this place only through the equivalent of space age technology. While every space vehicle has to accommodate the pressure difference of 1 atmosphere inside and none outside, Alvin has to withstand 200 atmospheres outside at the bottom of Guaymas Basin. Its current limit is 450 atmospheres and 4500 meters; the next upgrade will bring all systems to 6500 meters and 650 atmospheres. After this dive, Alvin will participate in one more cruise – a training cruise for aspiring PIs – and then returns to Woods Hole for the upgrade.

A last look at the hydrothermal landscape of Guaymas Basin, its oil-soaked sediments, microbial mats and shimmering waters. It never remains the same, as the hydrothermal fluids are constantly finding new flow paths through the sediments. The next visitors to Guaymas Basin will again find new hot spots, new sampling locations, and new microbial surprises and discoveries.

Unlike the 2001 Space odyssey, the Alvin 5001 dive team – from left, Vivian, Anthony and Todd – returns to Earth in good health and spirits. Alvin’s many computer systems do not develop their own devious plans.

Back on the Atlantis, Vivian has stories to tell, and she does so with energy and panache!

After Alvin returns, the Atlantis stays on station just long enough to complete one last CTD cast of the water column and the hydrothermal plume at Northern Cathedral Hill; then at around 10 pm we are off and steam southeast, towards Manzanillo. The two days of transit will get very busy!

At the start of this cruise we had not expected to make it to the Alvin dive 5000 benchmark, achieved 54 years after Alvin was launched in 1964. Yet, with good weather throughout the cruise and an additional if very short dive on Thanksgiving that advanced the official dive count by one, here we are!  Danik Forsman is piloting Alvin, and science observers Andreas Teske and Mandy Joye will join forces for this dive.

There are rumors to make this dive special, with interviews of the dive team while at the bottom etc. But this is a working dive – we have to deploy one long-term osmosampler that is supposed to last until February, when it will be picked up during a Guaymas visit by R/V Falkor; then there is an ambitious last-chance coring program, and animal, rock, and vent fluid collections. Of course we want to be a good dive team and systematically work through our coring program. The “collection” part of this dive takes place at the Northern Cathedral Hill site, and it turns into a spectacular surprise for everyone. Already the previous visit at this location during dive 4997 has revealed great hydrothermal scenery, but it turns out that was just a quick preview.

Here an octopus is hiding in his sponge-encrusted cave, and glowering at us and at the “Alvin 5000” sign that Danik has thoughtfully placed on his front porch. We tried to tease him to come out, but octopi are very territorial and do not leave their lair unless they have a very good reason. And anniversary photo shots do not fall into this category.

The octopus lives in the boulder field at the foot of Northern Cathedral Hill; we climb up a few meters and soon find the hydrothermal zone. The rising fluids that work their way through a hydrothermal mound emerge preferentially at the top.  The entire upper hydrothermal massif with hilltops and valleys is covered in microbial mats and Riftia gardens. This one is even larger than the “Wall of Riftia” encountered during Dive 4997. It is time to reassess this spot; it is not just a peculiar northern extension of our preferred mat sampling area, Cathedral Hill. Here we have an enormous hydrothermal mound on the same order of magnitude as its more famous siblings, Rebecca’s Roost ca. 150 m to the east, and Big Pagoda, ca. 500 m to the east. Looking for a proper name – what about Trondheim, the city in Norway with the northernmost gothic cathedral ?

Alvin hovers above the Riftia gardens in search of hot water flow. Just a little over to portside we notice a column of shimmering water rising; approaching it, an extensive flange – a protruding pagoda roof of hydrothermal minerals — studded with hydrothermal chimneys floats into view. The mineral-laden fluids that escape sideways build and extend the flange; after a while the fluids are creating additional escape vents through openings in the flange, which creates this intricate display of hydrothermal chimneys. All of them are highly brittle and crumble away if even touched; the clear shimmering vent fluids here probably contain fewer metal sulfides, which build up the backbone of most chimneys. We hover at this spot for quite a while.

Finally, we remember the PR part of this dive. The chimney garden is too delicate to place the “Alvin 5000” placard, and therefore Danik dangles it into the clear hydrothermal fluid. Fortunately the plastic does not melt. The placard is not merely embellishment of this dive; it is the spear tip of a never-ending outreach campaign that most research institutions have to go through, in particular soft-money institutions like the Woods Hole Oceanographic Institution that live by research grants from the government, industry and private foundations. As a former WHOI employee, this blogger is acutely aware that research activities have to be “packaged”. Even grant-granting institutions, for example the National Science Foundation, are not immune; since they get their budget from a stingy government, the same game repeats itself on yet another level. While you are reading this blog and increase visitor traffic, you are doing a meritorious service to the entire research enterprise by demonstrating your interest – and implicitly, some degree of approval – as a tax-paying and voting citizen.

Mysterious and unfathomable nature is unconcerned with the layers of publicity that are imposed on it, and its powerful presence reminds the scientists not to forget their true vocation. So we sample the vent fluids; they turn out to be 104-105 C hot at this spot, moderate by hydrothermal standards. The niskin bottles on the Alvin basket, originally designed for cooler water, fortunately hold and we can return these samples from their source at a deep-sea hot spring at 2000 m depth to the surface, for chemical analysis.

After returning to the ship, there is indeed a photo session! Dive team and the entire science crew get photographed innumerable times for this occasion, but we reserve this spot for one picture, the Alvin team. Without them, the entire science crew would be going nowhere. From left to right, Alvin tech Drew Brewley, Alvin expedition leader Todd Litke, pilot Anthony Tarantino, Jefferson Grau and Danik Forsman, Alvin techs Nick O’Sadcia and Lane Abrams.

Starting with this third-last dive, we are beginning to wrap up the deployments of deep-sea gear, and to recover the osmosamplers, T-loggers, and indispensable samples to round out the haul of sediment cores. The seas have calmed down, and Alvin emerges into a sunrise of Wagnerian grandeur.

Today, Alvin is piloted by Jefferson; in his capable hands are the science observers, Dirk deBeer, leader of the Microsensor Dept. of the Max-Planck-Institute for Marine Microbiology in Bremen with an unruly mop of grey hair that results from his previous participation in Guaymas cruises, and Roland Hatzenpichler, originally from Austria but now on the faculty at Montana State University. Roland usually works on hot spring microbial ecosystems in Yellowstone National Park, over 2000 meters above sea level, where he studies the physiological and biogeochemical activities of uncultured extreme microbes. Now he descends to 2000 meters below to finally experience the Guaymas hydrothermal springs that will keep him busy for quite a while.

This dive is extremely successful; all four osmosamplers plus their attendant T-loggers and satellite cores are recovered, a large number of background cores and several hot sediment cores from the M14 area are collected, not to forget a biological specimen that looks like a tangled piece of black wire but turns out to be a deep-water coral.

Here stands the small army of background cores, taken in cold sediment where Alvin has landed; these are needed as a reference of comparison for the numerous hydrothermal vent cores that were collected during this cruise. In the lab, it turns out that even some of these cores contain a whiff of hydrocarbons; obviously it is not easy to escape the fumes of Guaymas Basin entirely.

Here, Alvin is picking up one of the osmo samplers, pre-packaged in a milk crate, an essential device in oceanographic research. Osmo samplers have collected long-term porewater records at various places, including the brines and cold seeps of Mississippi Canyon 118 in the Gulf of Mexico; but this is their first deployment in Guaymas Basin. It will be exciting to see the porewater chemistry data that the samplers have collected during the last 24 hours.

At some safe distance, the elevator is waiting to be fully loaded, and released for the return to the surface. This ungainly-looking structure is indispensable for moving large pieces of equipment to the seafloor and back. Properly calibrated for minimal weight in water, it sheds weights when triggered and becomes buoyant, even with a full payload of equipment. However, releasing the elevator involves pulling particular strings, which is hard to do once sediments are resuspended. A 45-minute waiting game to let the dust settle is part of the day.

Finding all the osmosamplers, T-loggers and sediment cores gives the dive team plenty of opportunity to experience the strange scenery of the Marker 14 area, with its huge yellow-lime sulfur-stained mats. The weird black tangle in the center of this view is not a piece of barbed wire from a cattle ranch in Sonora; Javier identifies it as a deep-water coral, growing as a wiry bush with very thin and tangled black branches; it is frankly the strangest coral that this blogger has ever seen. The dive team sees a lot more unusual deep-sea fauna, even an anglerfish; we will look for the photo and have it posted asap.

 

After yesterdays last-minute recovery of the osmosamplers, the refitted units are ready to go down again on the elevator for deployment in the Aceto Balsamico area. Here the Alvin team and Andrew Montgomery of UGA put the finishing touches on  the elevator before it goes overboard and sinks to a (so we hope) predetermined spot where it can be easily found.

Soon enough, the dive team steps forward. Danik Forsman is piloting the sub, science observers Rick Peterson of Coastal Carolina University and Rachel Kearns from Mandy’s lab keep him company. In contrast to yesterday’s not overly optimistic dive team, they exude confidence and a sense for adventure! This is handy, especially since the wind is picking up…

Down in Guaymas Basin begins the reverse Osmosampler battle. The elevator has landed 300 meters off, has to be ferried to the Aceto balsamico site, and then finding the right spots for the osmosamplers is also not easy. A closer look at the site reveals an old dive marker [a.k.a. “science junk”], and the ultimate token of civilization: plastic trash on the seafloor, mostly old shopping bags. A community cleanup day in Guaymas Basin would be a nice idea…

The osmosamplers are deployed in various extraterrestrial microbial mat landscapes, and a huge coring program is concluded at breakneck speed before Alvin runs out of battery juice and has to return.

After the novice diver reception committee has staged an elaborate welcome for Rachael,  the cores are carried from the Alvin basket into the lab…

After core description in the cold room and core allocation, the Texas/Montana team is finally looking at “their” core. This column of stinky, smelly, and quite possibly poisonous mud, populated by innumerable microbes, is now your friend. Brett contemplates its murky presence and has mixed feelings. This will be a busy night!