Deep-sea chemistry
Day 9: All we could have hoped for August 18, 2011
Location: Dockside at Newport, Oregon 
The science team gathered for a photo by the remotely operated vehicle Doc Ricketts. Kneeling: Peter Brewer, left, and Peter Walz; Standing, from left, Nancy Barr, Laura Lapham, Liz Coward, Andreas Hofmann, Ed Peltzer, Michael Riedel, and Jon Furlong. This ocean expedition has been a great success, thanks to the experience, hard work, and planning that went into it, as well as support from the ship and ROV crews—and a dash of luck in terms of good weather. Ocean chemist Peter Brewer’s team returned to shore with quality data and video that are sure to lead to several significant publications in the field of gas hydrates and ocean chemistry. We greatly appreciate the professional and skilled ship crew who took care of our safety and well being all week: Captain Ian Young, First Mate George Gunther, and Second Mate Andrew McKee, on the bridge; Chief Engineer Matt Noyes and Second Engineer Lance Wardle; Electronics Officer Dan Chamberlain; Bosun Vinny Nunes; Steward Patrick Mitts; and our two relief crew members, filling in for those who could not sail on this leg of the expedition, Jason Jordan and Eric Fitzgerald. The talented ROV pilots did a fabulous job chasing bubbles and oil droplets all over the deep ocean. Thank you to Chief Pilot Knute Brekke, Deputy Chief Pilot Mark Talkovic, and pilots Bryan Schaefer, Eric Martin, and Randy Prickett. 
Some of the crew threw a few lines behind the ship in hopes of catching some tuna on the way home. It looked like Randy Prickett had a big one on the hook, until he pulled it in and found only seaweed. Some of our cruise-mates offer their thoughts on the expedition: Laura Lapham: Well, the cruise is over. As we make our final steam into port, I am reflecting on these past 10 days. It’s been pretty amazing to be out here with the MBARI group. As a guest, you always wonder whether you will fit in, or if your science will mesh with the cruise objectives. But as soon as I saw the Western Flyer, I felt instantly at ease. I remembered walking onto this ship 14 years ago as an MBARI intern, not realizing what my future had in store for me, but completely in awe of the ship and the ROV it held. I wondered if I would ever get to sail on the Flyer. But now, because of MBARI’s relationship with Canadian scientist Michael Riedel, and my longer term collaboration with Michael, this was now my second time on the Western Flyer (I was also invited to sail on the Flyer two years ago with Charlie Paull’s group). As I walked up the gangway, I was greeted by the friendly faces of Peter Brewer and Ed Peltzer, my mentors during my internship, and the rest of their science team. I also remembered the crew from two years ago, so it was like coming home. I was then pleasantly surprised to see the familiar face of the first mate, George Gunther, with whom I had sailed with in the Gulf of Mexico during graduate school. It’s nice to have friends in many places. And as for meshing science, I couldn’t be with a better group. Peter was the reason I got into gas hydrates in the first place. And now, we were working together, side by side. Seeing the laser Raman system hard at work, acquiring in situ methane profiles instantly, was amazing. I have collected many sediment cores in order to measure such profiles, all along knowing that the concentrations are not quite “in situ” because so much gas is lost when the core is retrieved from the seafloor. But now, having this tool means we can learn so much more about these methane-rich zones. I look forward to seeing where they will take the Raman next. Heck, for me, just being able to see the seafloor and gas hydrate outcrops with the ROV Doc Ricketts was a special experience! The ROV pilots continued to impress me as they attempted some very detailed manipulator work. They skillfully put one of my instruments on the top of a hydrate mound, and placed the very small wand attached to it, into the mud. It was almost like watching a giant place a normal size tack into a very specific place on a cork board. When they finished, it was exciting to know that the samplers were down there doing their job, collecting water samples continuously for the next year or so. With this type of data, we will better understand how dynamic the gas hydrate system is, especially when we can pair it up with data from the cabled observatory, NEPTUNE Canada, which collects continuous earthquake, pressure, and temperature measurements. With continued collaborations like the one with MBARI, I hope to gather these boxes within the next year, and see what we were able to capture. Until then, I sail home with good memories from this cruise and look forward to the next. 
Peter Walz packs up all the gear we used for our work this week. Liz Coward: Hello from the Western Flyer! I have been lucky enough to accompany the Brewer team on this leg of the Northwest Expedition, and I am so glad to be here! This has been an amazing end to the summer, witnessing the techniques I have learned in the laboratory executed on the seafloor, and instruments I helped build deployed 1,400 meters deep in the ocean. The Brewer team—Peter Brewer, Ed Peltzer, Peter Walz, and Andreas Hofmann—have been excellent mentors during my time at MBARI, and working with them at sea was no exception. I have, in eight short days, learned so much about the Flyer's operation, the ROV Doc Ricketts, and what it takes to conduct research on an oceanographic vessel. I've also met many inspiring people, including Nancy Barr, the Western Flyer crew, and our visiting colleagues, Michael Riedel, Laura Lapham, and Jon Furlong, who have all been wonderful to work with. Those eight days spent in the control room, eating delicious meals and record quantities of ice cream, enjoying the sunshine and calm seas, flying helicopters with the ROV pilots, and tying endless cable ties have only solidified my feelings that this is exactly where I want to be and what I want to be doing. Thank you so much to all the staff at MBARI who made my trip possible, to the Brewer Lab, and to everyone onboard this cruise for making this journey so extraordinary. Michael Riedel: My participation in this expedition was sparked by earlier scientific collaboration between MBARI and the Geological Survey of Canada, University of Victoria, and NEPTUNE-Canada. In 2009, I was onboard the Western Flyer with MBARI scientist Dr. Charles Paull investigating cold vents and associated seafloor gas expulsion in this area. Dr. Brewer, chief scientist of this expedition, invited me to sail on this cruise to help find suitable locations for his experiments of ocean geochemistry. One of the most fundamental scientific questions we are pursuing is unravelling the linkages between tectonic activity and fluid expulsion, as well as changes in sediment geochemistry, and the biology of the vent sites at the seafloor. In 2009, we started a long-term observation strategy in collaboration with Dr. Laura Lapham from Florida State University, deploying instruments to study natural gas and oil expulsion. In 2009, two of these sampling instrument packages were deployed at Barkley Canyon and at a vent-field, informally named “Bubbly Gulch”. This year’s expedition gave us the opportunity to expand the time-series analysis on the same sites and help answer the question if earthquakes spark fluid expulsion and gas release... Read more. We will be leaving the ship in Newport, but the crew will stay on and head out to sea in a few days with MBARI geologist Charlie Paull and his group. Stay tuned to read about their explorations of the muddy bottom.
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 Track the ship
Equipment
 R/V Western FlyerThe R/V Western Flyer is a small water-plane area twin hull (SWATH) oceanographic research vessel measuring 35.6 meters long and 16.2 meters wide. It was designed and constructed for MBARI to serve as the support vessel for ROV operations. Her missions include the Monterey Bay as well as extended cruises to Hawaii, Gulf of California and the Pacific Northwest.
ROV Doc Ricketts is MBARI's next generation ROV. The system breaks new ground in providing an integrated unmanned submersible research platform, with many powerful features providing efficient, reliable and precise sampling and data collection in a wide range of missions.
By bouncing a specially tuned laser beam off of almost any object or substance—solid, liquid, or gas—a laser Raman spectrometer can provide information about that object's chemical composition and molecular structure.
A push-core looks like a clear plastic tube with a rubber handle on one end. Just as its name implies, the push core is pushed down into loose sediment using the ROV's manipulator arm. As the sediment fills up the core, water exits out the top through one-way valves. When the core is pulled up again, these valves close, which (most of the time) keeps the sediment from sliding out of the core tube. When we bring these cores back to the surface, we typically look for living animals and organic material in the sediments.
Vibracoring is a common technique used to obtain samples from water-saturated sediment. These corers work by attaching a motor that induces high frequency vibrations in the core liner that in turn liquefies the sediment directly around the core cutter, enabling it to pass through the sediment with little resistance.
Carbon dioxide is a liquid at the temperatures and pressures on the seafloor where hydrates are known to occur. Because of this, one cannot simply take down a tank of gas and expect to be able to release it at depth. Instead, the CO2 piston accumulator is used to deliver precise volumes of liquid CO,2 to experiments on the seafloor. The valves are operated hydraulically by remote control and hydraulic pressure is used to expel the liquid CO2 and deliver it to the experiments.
MBARI's heat-flow probe is mounted on the side of the ROV Doc Ricketts inside the vertical stainless steel box. This both protects the delicate probe and provide the track so that the probe can be inserted into the sediment along a totally straight path. The probe contains five high precision platinum sensors which are used to measure the vertical temperature gradient in the sediments. This gradient along with some knowledge of the heat capacity of the sediment allows scientists to calculate the rate of heat loss from the sediments into the ocean. Crew
R/V Western Flyer
ROV Doc Ricketts
Research Team
Peter has taken part in more than 30 deep-sea cruises, and has served as chief scientist on major expeditions and on more than 90 ROV dives with MBARI ships and vehicles. His research interests include the ocean geochemistry of the greenhouse gases. He has devised novel techniques both for measurement and for extracting the oceanic signatures of global change. At MBARI his current interests include the geochemistry of gas hydrates, and the evolution of the oceanic fossil fuel CO2 signal. He has developed novel techniques for deep ocean laser Raman spectroscopy, and for testing the principles and impacts of deep ocean CO2 injection.
Ed is an ocean chemist who has been with MBARI since 1997. He has been involved in developing in situ laser Raman spectrometry instruments and lab based analytical techniques to study the composition of gases in gas hydrates and deep-sea vents. He has collaborated on the development of new instrumentation for the measurement of temperature and pH from ROVs and deep-sea observatories. As the group's project manager, Ed is also responsible for expedition planning and logistics.
Peter has worked as a research technician for a variety of scientists at MBARI. Most recently he has supported the research efforts of Dr. Peter Brewer and his interests in the ocean chemistry of greenhouse gases such as methane and carbon dioxide. Peter assists with the design, testing and deployment of the ocean going science hardware and works closely with the marine operations group to integrate new equipment to work with MBARI's ROV's.
Andreas is a MBARI Postdoctoral Fellow in the Brewer lab. He obtained a PhD in marine biogeochemistry in the Netherlands after his biology undergraduate and bioinformatics graduate studies in Germany. Andreas' specialty is pelagic and benthic biogeochemical modeling with a focus on pH and proton cycling. At MBARI, Andreas is working amongst others on the characterization of marine hypoxic and suboxic zones, focusing on the explicit description of physical limitations to aerobic respiration. On this cruise, Andreas will be involved in obtaining and processing Raman spectra, as well as in various other tasks supporting the objectives of the group.
Nancy manages the editing, design, and production of the MBARI annual report and participates in a variety of editorial and communication projects. She also oversees the institute website. Nancy has been to sea with several MBARI research groups, helping them to carefully remove worms from whale bones, annotate video, sift seafloor sediment, and collect and process water samples. For this expedition she will be in charge of the daily reports that will be posted to this website and will assist with other science crew tasks.
Elizabeth is an MBARI summer intern in the Brewer lab. She is a senior at Haverford College, PA, where she is obtaining her undergraduate joint degree in biology and chemistry. Elizabeth's prior research has been principally concerned with the bioavailability and geochemical dynamics of oil in marine sediments. Her interest in oceanic fossil fuels and greenhouse gases has brought her to the Brewer lab, where she will be using laser Raman spectroscopy to investigate methane and carbon dioxide signatures, the dynamics of gas hydrates and ocean acidification.
Michael Riedel was part of an international team of scientists supported by the Integrated Ocean Drilling Program (IODP) which completed a unique research expedition in 2005 aimed at recovering samples of gas hydrate, an ice-like substance hidden beneath the seafloor off Canada's western coast. As IODP Expedition 311's co-chief scientist, Michael explored his interest in gas hydrate; he believes such deposits have played an important role in ancient global climate change.
Laura's research is concentrated on studying methane cycling at cold seeps, biogeochemcial cycling of methane and sulfer in deep sea sediments, development of deep sea instrumentation to collect novel samples, stable isotope geochemistry, modeling of biogeochemical processes and temporal variability of dissolved methane concentrations. The focus of her research has been mainly on gas hydrate environments, but she is also interested in other systems that relate to the carbon cycle. Her research seeks to understand how methane is distributed between different pools, e.g. dissolved or hydrate phases, and also to understand how local biogeochemical processes affect this methane, mostly through anaerobic methane oxidation.
Jon is a graduate student at the University of Victoria studying with Michael Riedel. His bachelor's degree was completed in Earth Sciences from Memorial University in Newfoundland before he moved from one coast to the other. Jon's research focuses on neo-tectonic faulting offshore Vancouver Island and its links to gas hydrate formation and fluid migration. |
