Monterey Bay Aquarium Research Institute
2010 SouthernExpedition


Day 9 – Probing and testing
July 17, 2010

1830 hours – Santa Monica mounds
Latitude 33 degrees 47.9482 minutes N
Longitude 118 degrees 38.7503 W

After yesterday’s successful pairing of the laser Raman pore-water probe and the vibracoring system, today was spent further testing the tools and technique while gathering more data. The team learned what worked well with this new system and what didn’t work so well.

The day allowed for two dives. Between dives, the ROV was outfitted with new vibracores and the ship took us to a different site about a kilometer away. A number of gas measurements were taken with the pore-water probe, both with the vibracore laying on the seafloor (see yesterday’s photo) and directly into the sediment. The data will be analyzed by the scientists following this expedition. Using a new technique involves a lot of improvising along the way, as the science team and the pilots learn the best way to take samples and measurements and how to manipulate the tools on the seafloor. All the while, the two teams talk about how they can do it better next time, or what path to take in developing tools for future efforts.

A cruise can be exciting, interesting, and fun—and this expedition has been all that—but the truth is that there are also periods as exciting as watching paint dry. Waiting while an instrument is calibrated or watching a valve being opened and closed on the seafloor are not so thrilling. But when the persistence and patience pay off with a breakthrough with a new tool or a new discovery, the excitement aboard is palpable.

Chief Scientist Peter Brewer points out the gasses still bubbling out of the vibracore after it is brought to the surface. This illustrates how sediment samples lose much of their gases as the sediment is brought up from the deep sea.

Yesterday I mentioned the ROV pilots who work so hard to keep the vehicle in top working order and to accommodate all the science team’s ideas (which can be pretty wild and crazy sometimes). The other very important group on board is, of course, the ship’s crew. Captain Ian Young and his crew look out for the safety of the ship and everyone aboard, yet still allow the scientists the latitude to accomplish what they set out to do. For the scientists who come aboard for a week or two, it is a great comfort to know this crew is providing the support to make our work possible. Thank you to the crew, and to all the support staff in the MBARI Division of Marine Operations who helped with this expedition.

When the science team decided they wanted to take more cores than they had brought along, engineer Jim Boedecker, above right, quickly fashioned a new core from tools and supplies on board. (Pictured with Jim is Shaun Summers, one of MBARI’s relief crew members, who is working as an engineer on this expedition.) Later, Peter Walz and Ed Peltzer made another vibracore by drilling in the holes for the insertion of the pore-water probe.

Cras ingens iterabimus aequor
Tomorrow we'll sail the mighty deep once more.
--Horace

—Nancy Barr

Steward Patrick Mitts serves 23 people each meal, yet still manages to put together such gourmet treats as macadamia encrusted lamb and kung pao chicken. Photo by Andreas Hofmann.
Dan Chamberlain helps with the recovery of the ROV.
Photo by Peter Walz
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Leg 1
 Equipment

R/V Western Flyer

The 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

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.

Laser Raman spectrometer DORISS2

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.


Push cores

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 ROV Tiburon'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.

Vibracores

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.


CTD Rosette

A CTD rosette is a cylindrical frame holding a group of plastic water-sampling tubes. Attached to this frame are instruments for measuring water temperature and conductivity (salinity) at various depths. Also attached to the rosette are instruments for measuring parameters such as chlorophyll, nutrients, and particulate matter in the water. As the frame is lowered over the side of a ship, water samples are taken automatically at various depths. Then the frame is raised to the surface again.


 Research Team

Peter Brewer
Senior Scientist, MBARI

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 Peltzer
Senior Research Specialist, MBARI

Ed is an ocean chemist who has been with MBARI since 1997. He has been involved in developing instrumentation and analytical techniques to study the composition of gases in gas hydrates and deep-sea vents. He has also collaborated on the development of new instrumentation for the measurement of temperature and pH from an ROV. As the group's project manager, Ed is also responsible for expedition planning and logistics.

Peter Walz
Senior Research Technician, MBARI

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 Hofmann
Postdoctoral Fellow, MBARI

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 on the relation between pH and soundspeed, the characterization of marine "dead zones", the development of a sediment model to estimate biogeochemical rates from pore-water methane profiles obtained with the group's deep sea sediment Raman Probe, and on a few other related topics. On this cruise, Andreas will be involved in experiments using the mid-water CO2 and O2 control system and the sediment Raman probe, as well as in various data processing tasks.

Melissa Luna
Summer Intern, MBARI

Melissa is an MBARI 2010 Summer Intern working in the Brewer lab. She is a graduate of College of Charleston in Charleston, South Carolina with a BS in Chemistry. This summer Melissa will be working on using laser Raman techniques to examine hydrogen sulfide and bisulfide signals as a function of pH in marine pore waters in sea floor sediments.

Nancy Barr
Web/Print Project Manager, MBARI

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.

Xin Zhang
Seafloor Hydrothermal Activity Laboratory
Key Lab of Marine Geology and Environment
Institute of Oceanology, Chinese Academy of Sciences

Xin Zhang is a former MBARI student of Peter Brewer and Bill Kirkwood. He was involved in the development of a Deep-Sea Raman Probe for the measurement of sediment pore-water geochemistry.

Zeng Zhigang
Director, Seafloor Hydrothermal Activity Laboratory
Key Laboratory of Marine Geology and Environment
Institute of Oceanology, Chinese Academy of Sciences

Zeng Zhigang's research interests are in hydrothermal vents, geochemistry, economic geology, and the exploration of geology and mineral resources. He is on this expedition to learn more about MBARI's tools and methods for study ocean chemistry.