Monterey Bay Aquarium Research Institute

 


July 22, 2011

Location: North Cleft of the Juan de Fuca Ridge
Latitude: 44°57.8' N
Longitude: 130°12.5’ W

Today we continued our investigation of the young lava flows at the northern Cleft segment of the Juan de Fuca spreading center. Many of our objectives were similar to those described in the previous cruise log by Jenny. Today, I will add context for some of the features we observed on the seafloor today while flying around with the ROV Doc Ricketts.

We primarily saw three lava morphologies or shapes of lava forms: sheet, lobate, and pillow flows. These morphologies are related to the eruption rate. Put another way, more vigorous eruptions tend to erupt lavas that look more fluid and slower eruptions tend to erupt more "pasty" (like toothpaste) lavas. Once molten lava interacts with cold seawater, the surface of the flow cools very rapidly, typically forming a glassy exterior, and these lava flow morphologies are literally frozen-in…just waiting for scientists to observe and sample them in the future!

To the uninitiated, many of the features found on the seafloor might look barren or like a rubble pile. However, to the trained eye with the right tools and preparation, the following observation created a bit of excitement in the ROV control room. Allow me to explain: many months ago, members of MBARI’s submarine volcanism project were using high-resolution bathymetric maps of the seafloor (created with MBARI’s AUV D. Allan B.) to outline boundaries of individual submarine lava flows along the Juan de Fuca ridge (we’re also working on new ways to constrain the ages of young submarine lava flows). The fine scale of these maps represent a major technological advancement, but it remains gratifying to have a contact between two lava flow morphologies predicted onshore bear out during a subsequent submarine ROV observation.

Contact! An older jumbled sheet flow has been overtopped by a younger pillow lava.

Here’s an example of what we were searching for on the seafloor today—a near ideal sampling site. We were often looking for a single location to take small pieces of lava and a sediment pushcore. Here, the broken pillow offers the perfect premade handle for the ROV manipulator’s jaws; without something to grasp, spherical pillow lava can be quite challenging to sample. Also, there was a small sediment pond just in front of the broken pillow lava which we were able collect cleanly.

An ideal sample location for pillow lava (broken, background) and sediment (foreground and collected in pushcore) in the same location.

There were several other highlights of the dive. Beyond the spectacular visual display of the “lava condos” that are often created in collapsed lava lakes (see yesterday’s cruise log), they offer outstanding insights into how lava behaves on the seafloor (as well as initiating more questions such as: where does the drained lava go?). Below is another cool image, this of a lava pillar, also found in collapsed lava terrain. See the "bathtub rings"? They record the lava lake level as it drained away sometime after it reached its peak. One can also determine that the lava flow had a somewhat lobate morphology with a relatively thick exterior crust.

The crest of a lava pillar that stands several meters tall within sheet flows (not visible) in a collapsed lava lake in the northern Cleft segment of Juan de Fuca Ridge.

New oceanic crust is continually formed at spreading centers that wind around the Earth, like stitches on a baseball. Here, magma ascends from several miles depth, and some portion of it erupts onto the seafloor mainly through the relatively narrow spreading center axis. The axis of the Juan de Fuca Ridge spreading center lies just approximately 400 kilomters west of the Pacific Northwest, and hosts an amazing diversity of volcanologic and biological production—much of it remains underexplored with new and emerging technologies.

— Brian Dreyer

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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.

Deep ESP

The ESP is a self-contained robotic laboratory that collects samples of seawater and tests these samples for different types of microorganisms, either their genetic material, such as DNA, or proteins they may secrete, such as toxins from a harmful algae bloom. Because of the immense pressure in the deep sea, MBARI's researchers had to build a special pressure housing to protect the delicate instrument. They also had to design and build an automated system to "depressurize" seawater before it could be introduced into the ESP.


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 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.

Niskin bottles

Niskin bottles are used to collect water samples as well as the tiny bacteria and plankton in that volume. The caps at both ends are open until the bottles are tripped, when the caps snap closed.


Biobox

The box fits in a partition in the sample drawer. It is shown open, with an animal being placed into it by the ROV's manipulator. When the lid is closed, the box will hold water to protect the animals inside.


Rock crusher

This device is used to collect volcanic glass fragments from the surface of a flow. It is made of about 450kg of lead and steel and is launched over the stern of the ship on a wire. Fragments of rock that break off of the lava flow on impact are trapped in wax-tipped cones mounted around the crusher. The wax is melted in the lab to liberate the rock particles for analysis.

Benthic toolsled/
Manipulator arm/
Sample drawer with partitions

The benthic toolsled is attached to the bottom of the ROV for our geology dives. Its components are the manipulator arm and the sample drawer. The sample drawer is shown open on deck, full of rocks. Normally it is closed when the vehicle is operating and is opened only when a sample needs to be stowed. Partitions in the drawer help us keep the rocks in order. The rocks often look alike, but the conditions and chemistries of the eruptions are different so it is important that we know where each came from.

Glass suction sampler

This equipment is used to vacuum glass particles and larval animals from cracks and crevices. The carousel of small plastic jars fitted with wire mesh will be mounted in the benthic toolsled. The hose will be held by the ROV's manipulator and a suction will be drawn by the pump.

Sediment scoops

Canvas bags on a T-handle for collecting gravel or other materials that fall out of a push-core.


Temperature probe

Mounted on the D-ESP, the wire on the right is placed into the fluid emitted from a hydrothermal vent to record the temperature.

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.


 Crew

R/V Western Flyer

Ian Young
Master


 

George Gunther
First Mate


 

Lance Wardle
Chief Engineer


 

Andrew McKee
Second Mate


 

Paul Tucker
First Engineer


 

Olin Jordan
Oiler


 

Vincent Nunes
Bosun


 

Dan Chamberlain
Electronics Officer


 

Patrick Mitts
Steward


 

ROV Doc Ricketts

Knute Brekke
Chief ROV Pilot


 

Mark Talkovic
Senior ROV Pilot


 

Randy Prickett
Senior ROV Pilot


 

Bryan Schaefer
ROV Pilot/Technician


 

Eric Martin
ROV Pilot/Technician


 

 Research Team

Peter Girguis
Chief Scientist
Harvard University

Peter Girguis is currently a John L. Loeb Associate Professor of Natural Sciences at Harvard University, and an adjunct research engineer at MBARI. His research focuses the ecological physiology of microbes that live in extreme environments. He is particularily interested in the physiological and biochemical adaptations to life in anaerobic environments. His research lies at the intersection of biology and geochemistry, and he develops and uses a variety of tools (high-pressure systems, in situ mass spectrometers, in situ microbial fuel cells) to address the aforementioned issues. He received his B.Sc. from UCLA and his Ph.D. from the University of California Santa Barbara, where he worked with Dr. James Childress on the physiological and biochemical adaptations of deep sea hydrothermal vent tubeworms and their microbial symbionts to the vent environment. He did postdoctoral research at the Monterey Bay Aquarium Research Institute with Dr. Edward Delong on the growth and population dynamics of anaerobic methanotrophs.

David Clague
Chief Scientist
MBARI

Dave's research interests are nearly all related to the formation and degradation of oceanic volcanoes, particularly Hawaiian volcanoes, mid-ocean ridges, and isolated seamounts. Topics of interest include: compositions of mantle sources for basaltic magmas and conditions of melting; volatile and rare-gas components in basaltic magmas and their degassing history; chronostratigraphic studies of eruption sequence and evolution of lava chemistry during volcano growth; subsidence of ocean volcanoes and its related crustal flexure, plate deformation, and magmatic activity; geologic setting of hydrothermal activity; origin of isolated seamounts; and monitoring of magmatic, tectonic, and hydrothermal activity at submarine and subaerial volcanoes.

Jenny Paduan
Senior Research Technician
MBARI

Jenny works with Dave Clague in the Submarine Volcanism project. On this expedition, Jenny will be in charge of the GIS work, including use of the recently acquired, high-resolution MBARI Mapping AUV data of our dive sites. She will also stand watches in the ROV control room, help with rock and sediment sample workup and curation once the vehicle is on deck, and coordinate these cruise logs for our group's two legs of the expedition. She is now quite solidly a marine geologist, but her degrees are in biochemistry (Smith College) and biological oceanography (Oregon State University). She is thankful for the opportunities that have led her to study volcanoes, and loves being involved with the research and going to sea. She looks forward to discovering more about how the Earth works.

Bill Ussler
Senior Research Specialist
MBARI

During expeditions, Bill Ussler is primarily responsible for the operation of the custom-built, portable chemistry lab van which contains a complete analytical laboratory for the analysis of the fluids and gases contained in marine sediments. Bill studies how methane (natural gas) forms and moves within seafloor sediments.

scott jensen Scott Jensen
ESP Systems Lead Engineer
MBARI


doug pargett Doug Pargett
Deep-water Operations Lead Engineer
MBARI


chris preston Chris Preston
Senior Research Technician
MBARI


brent roman Brent Roman
System Control Lead Engineer
MBARI

Brent has been playing with computers and control systems since the late 1970s. He wrote embedded control software for video tape editing while attending the University of California at Santa Cruz, where he earned a B.S. in Computer and Information Sciences in 1985. His main technical interests are computer operating systems, languages and feedback control systems. Brent wrote most of the custom software driving the current generation of the Environmental Sample Processor. He also enjoys sailing.

Brian Dreyer
Institute of Marine Sciences
UC Santa Cruz

Brian is an isotope geologist in the Institute of Marine Sciences at UC Santa Cruz where he studies the recent magmagenesis and petrology of the Juan de Fuca Ridge. His interest in the petrology of mid-ocean ridges began during his postdoctoral fellowship with MBARI's Submarine Volcanism Group; there, he utilized uranium-series disequilibria within individual lavas of Axial Seamount to clarify eruption and petrogenetic timescales. At mid-ocean ridge systems globally, Brian is interested in a) how variability in lava morphology, geochemistry, and petrology reflect deeper mantle-melting and magmatic processes and their complex interplay with tectonism and b) improving the chronological framework of the ridge magmatic plumbing systems. Brian received his B.S. in Geology from Cal State East Bay in 2000 and PhD in Earth and Planetary Science from Washington University in St. Louis in 2007. When not on the Western Flyer this summer, Brian defends the left side of the infield for the Surfing Squirrels, MBARI's coed softball team.

Heather Olins
Graduate Student
Harvard University

Heather Olins is a graduate student at Harvard University in the Girguis Lab. Her research focuses on carbon fixation, microbe-mineral interactions, and biogeography of hydrothermal vent microbes. She is interested in the interactions of microbes with their physical environment in the deep sea, and determining the role of those interactions in global biogeochemical cycles. Heather received her B.A. and M.A. in Earth and Environmental Sciences from Wesleyan University. On this cruise Heather will be helping with the microbiology associated with the D-ESP and also deploying microbial samplers designed to investigate the impact that mineralogy has on microbial colonization and community structure in vent ecosystems.

Charles Vidoudez
Postdoctoral Fellow
Harvard University

Charles has a multidisciplinary background in plant biochemistry, biotechnology, chemical ecology, metabolomics and mass spectrometry. He obtained his Ph.D in chemical ecology at the Friedrich-Schiller University in Jena, Germany, working on developing and using metabolomics methods on diatoms. Charles's postdoctoral research focuses on combining all these techniques to better understand the deep-sea ecosystems. He currently uses and further develops in situ mass spectrometers. These instruments are a highlight of the Girguis lab and allow direct in situ characterization of the gases dissolved in the seawater, especially at hydrothermal vent sites.