Seafloor Volcanoes - Background
Chief Scientist: David Clague
Leg 1: 12 - 23 July 2011
Leg 2: 27 July - 6 August 2011

Although many research papers indicate that they are using high-resolution bathymetry, the meaning of high-resolution has changed dramatically in the past five years. Using the mapping AUV, MBARI has now collected one-meter bathymetry of the Endeavour Ridge, the summit and upper south rift of Axial volcano including full coverage of both 1998 lava flows, the CoAxial site of the 1993 and 1982-1991 eruptions, and the North Cleft 1986 pillow ridge and an extensive sheet flow nearby, creatively named the Young Sheet Flow since it looked young at the time the pillow ridge was explored in the late 1980s and early 1990s.

Over the past few years MBARI researchers have been combining the map data with ROV observations of young/old flow relationships to develop confidence that they can not only map flow boundaries, but identify old/young relationships from the maps. The last piece of the puzzle has been to establish some time constraints, which is done in a way analogous to constraining ages in young lava fields on land (where flows are commonly dated by collecting and radiocarbon dating charcoal from beneath flow edges). Under water, there of course is no charcoal produced and it is not possible to excavate below the flow margins, so they do the next best thing, which is to collect short push cores of the sediment on top of the flows. For the entire Juan de Fuca region MBARI researchers have found that enough sediment concentrates that it can be collected, especially among pillow basalts, for flows older than about 500 years. Foraminifera is extracted from the bottom one centimeter of the core for radiocarbon dating, which yields a minimum age of the flow beneath. This will be a major objective of the North Cleft* and CoAxial dives.

At the same time the research team is collecting cores, they will collect lava samples for geochemistry. As an example, they have found that lavas on the floor of the caldera at Axial volcano and the lavas on the rim from eruptions that flowed away from the summit prior to collapse of the caldera as well as the flows exposed in the caldera walls are chemically and mineralogically distinctive. They can now look at how the lavas change through time.

Another objective is to determine the time of formation of the caldera. The rim is buried under as much as two meters of volcaniclastic debris that the team has tried unsuccessfully to core several times. The goal is to try to build a chemical stratigraphy of the pyroclasts in the section using a series of age dates on foraminifera from the section.

At Endeavour Ridge, the Clague team's goal is similar to that at Axial: to determine when the axial valley containing the extensive hydrothermal deposits began to collapse. As at Axial, the plan is to collect cores of the sediment on top of flows on the valley rims that flowed away from the axial valley. These should provide ages that predate the collapse of the axial valley and development of the extensive faulting that provide the conduits for hydrothermal fluid flow.

At Vance Seamount C, Clague's research team will conduct one dive to further explore thick volcaniclastic units on the rim of a caldera. In this case, the volcaniclastics are lithified, but the team will attempt to collect a section through them and try to determine where they erupted and how they were transported and deposited.

One additional thing Clague's research team is studying is the colonization by benthic animals on the historic flows, and to use this as a means to assess ages of very young flows. Having collected transect data twice previously on the historic flows, they will try to add a few more transects this trip as well. The ROV is flown at a set height above the bottom for 100 meters, and the video is then quantitatively analyzed by counting every animal observed in the field of view.

*The dives at North Cleft may actually occur on Leg 1, for logistical reasons.

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Suggested reading

The 1993 CoAxial eruption, a collection of papers in Geophysical Research Letters, 22, No. 2 in 1995. These papers describe the mega-plume emitted during the eruption, the seismic swarm that accompanied the eruption, and initial results on the character of the eruption.

The 1998 Axial Seamount eruption, a collection of papers in Geophysical Research Letters, 26, No. 23 in 1999. Same sort of collection for the 1998 Axial eruption.

Chadwick, J., Perfit, M., Ridley, I., Kamenov, G., Chadwick, W.W., Embley, R.W., le Roux, P., and Smith, M., 2005, J. Geophys. Res., 110, doi:10.1029/2003JB002767. Petrology of Axial Seamount, mainly based on samples from the south caldera and south rift zone.

Chadwick, W.W., Jr., and Embley, R.W., 1994, Lava flows from a mid-1980s submarine eruption on the Cleft segment, Juan de Fuca Ridge, J. Geophys. Res. 99, 4761-4776. Describes the 1986 North Cleft eruption distribution and morphology.

Chadwick, W.W., Jr., Scheirer, D.S., Embley, R.W., and Johnson, H.P., 2001, High-resolution bathymetric surveys using scanning sonars: Lava flow morphology, hydrothermal vents, and geologic structure at recent eruption sites on the Juan de Fuca Ridge, J. Geophys. Res., 106, 16,075-16,099. Describes the North Cleft and CoAxial eruption sites.

Clague, D.A., Paduan, J.B. (2009) Submarine basaltic volcanism, In: Submarine Volcanism and Mineralization: Modern through Ancient, B. Cousens and S.J. Piercey (eds.), Geological Association of Canada, Short Course 39-30 May 2008, Quebec City, Canada, p. 41-60.

Clague, D.A., Paduan, J.B., and Davis, A.S., 2009, Widespread stombolian eruptions of mid-ocean ridge basalt, J. Volcanol. Geotherm. Res., 2009, 180, 171-188. Describes the fragmental eruption products of strombolian bubble-burst activity on Pacific mid-ocean ridges, including Gorda and Juan de Fuca ridges, near-ridge seamounts, and a few back-arc basins.

Clague, D.A., Reynolds, J.R., 2000, Near-ridge seamount chains in the northeastern Pacific Ocean, J. Geophys. Res. 105, 16541-16561. Describes nested calderas on near-ridge seamounts including Vance.

Embley, R.W. Chadwick, W.W., Perfit, M.R., Smith, M.C., and Delaney, J.R., 2000, Recent eruptions on the CoAxial segment of the Juan de Fuca Ridge: Implications for mid-ocean ridge accretion processes, J. Geophys. Res., 105, 16,501-16,525. A synthesis of what was known at that time about the 1993 and an adjacent pillow ridge emplaced between surveys done in 1982 and 1991.

Embley, R.W., Murphy, K.M., and Fox, C.G., 1990, High-resolution studies of the summit of Axial volcano, J. Geophys. Res., 95, 12,785-12,812. Best overall description of the caldera and summit of Axial volcano.

Karsten, J.L., Hammond, S.R., Davis, E.E., and Currie, R.G. 1986, Detailed morphology and neotectonics of the Endeavour Segment, Juan de Fuca Ridge: New results from Seabeam swath mapping, Geol. Soc. Am. Bulletin, 97, 213-221 Describes the tectonics and morphology of the Endeavour ridge.

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Leg 1

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.


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.


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.


R/V Western Flyer

Ian Young


George Gunther
First Mate


Lance Wardle
Chief Engineer


Andrew McKee
Second Mate


Paul Tucker
First Engineer


Olin Jordan


Vincent Nunes


Dan Chamberlain
Electronics Officer


Patrick Mitts


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

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

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

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

doug pargett Doug Pargett
Deep-water Operations Lead Engineer

chris preston Chris Preston
Senior Research Technician

brent roman Brent Roman
System Control Lead Engineer

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.