Monterey Bay Aquarium Research Institute
2009 Pacific Northwest Expedition


Leg 1 Logbook - Laser Raman Spectroscopy
Day 3 – If it is cloudy then this must be Oregon…
July 9, 2009

0900 hours – Underway off the coast of Oregon.
Latitude 41 degrees 54.9 minutes N.
Longitude 125 degrees 35.0 minutes W.
Speed: 9.5 knots

With our dive site at Hydrate Ridge less than a days steam away, preparations to deploy the elevator and launch ROV Ricketts intensified today. Peter Walz spent most of the morning working with the pilots making sure all of the equipment was properly mounted on the movable front porch of the ROV.

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Peter Walz and the ROV pilots carefully inspect the operation of the movable porch on ROV Doc Ricketts. The platform has to move in and out without snagging any of the hydraulic or fiber optic lines running to the equipment in the tool tray. It is a delicate operation that the ROV pilots have done many times and is critical to the successfully deployment of the laser Raman spectrometer pore water probe.

Later, Ed Peltzer helped Peter mount a pH sensor to one of the forward struts on the ROV. After lunch Keith and Peter made the elevator ready on the aft deck for deployment first thing tomorrow morning. And Xin Zhang spent the better part of the afternoon practicing sampling pore waters in the wet lab. Ed Peltzer spent the afternoon reviewing the navigation data from the last Brewer group visit to Barkley Canyon.

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Ed Peltzer and Peter Walz mount a pH sensor to the forward strut on the ROV frame. While use of these sensors is now routine on ROV Ventana, this will be the first chance we have had to test their operation with the new ROV and the test is eagerly anticipated.

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Keith Hester and Peter Walz test the fit of the hydrate experimental chambers in the extension brackets on the elevator frame prior to securing them for deployment.

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Xin Zhang practices extracting pore waters from a sediment push core.

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Ed Peltzer diligently analyzes the ROV navigation data from the last visit to Barkley Canyon in 2006. By knowing precisely where we were then, we can choose our dive targets for this expedition wisely. Old sites can be easily re-visited; new sites can be explored in a systematic fashion.

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Lastly, we bring you the first photo in our “How well do you know the Western Flyer Quiz.” Can you identify the mystery substance in this photo and where it is located? The answer will be revealed in a few days in an upcoming daily log.
Stay tuned …

—Ed Peltzer

 

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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.


CO2 accumulator

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.


Heat-flow probe

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.


 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.

Xin Zhang
Graduate Student, Ocean University of China & Visiting Investigator, MBARI

Xin Zhang is a Ph.D. student from the Ocean University of China and is now studying at MBARI with Peter Brewer and Bill Kirkwood. He has been involved in the development of a Deep-Sea Raman Probe for the measurement of sediment pore water geochemistry. In this expedition, he will focus on obtaining the in situ pore water Raman spectra and the collection of pore water samples for subsequent shipboard analyses by ion and gas chromatography.

Keith Hester
Conoco Phillips

Keith is currently an associate engineer with ConocoPhillips focused on natural gas hydrates. Keith received his PhD in Chemical Engineering from the Colorado School of Mines in 2007. This was followed by a two-year postdoctoral fellowship at the Monterey Bay Aquarium Research Institute with Dr. Peter Brewer. His research interests include the use of carbon dioxide to replace methane in natural hydrates.

John Ripmeester
Principal Research Officer, Materials Structure and Function Group
National Research Council Canada

John has been a staff member at the NRC since 1974, first with the Division of Chemistry, then with the Steacie Institute for Molecular Sciences upon its establishment in 1991. His research focuses on the chemical applications of solid state nuclear magnetic resonance (NMR) spectroscopy, the development of multi-technique approaches to the characterization of materials, supramolecular chemistry, porous materials, clathrates, gas hydrates, and other guest-host materials. He has nearly 500 publications and six patents and is often an invited speaker at special events.