Biology Meets Subduction

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Biology Meets Subduction

Integrating deep carbon science in the field

On 11 February 2017, 25 researchers from six nations met in San Jose, Costa Rica for a 12-day sampling expedition across the Costa Rica volcanic arc. Members of the four Deep Carbon Observatory Science Communities are conducting a scientific investigation at Costa Rican volcanic sites through the lenses of biology, chemistry, physics, and geology. This multidisciplinary view is affording researchers from different fields the unique opportunity to work side by side, sharing their insights, and asking questions to achieve a broader picture of the role of carbon in this active volcanic arc.
The sampling expedition “Biology Meets Subduction: A Collaborative and Multidisciplinary Deep Carbon Field Initiative” is designed to develop novel connections between microbiology, volcanic systems, and the cycling of living and dead (biotic and abiotic) carbon as Earth’s plates move and subduct past each other. The goal is to determine how carbon is involved in each of these processes. The knowledge gained will shed light on carbon movement between Earth’s surface and interior and the biological and chemical changes that occur en route. This is a unique opportunity for scientists to share perspectives and knowledge, bringing to bear exciting and novel scientific outcomes.
Why Costa Rica?
The team selected Costa Rica as a study site because several other teams have investigated its active volcanoes and subduction zones, providing important contextual data for further exploration. Offshore, the area has been investigated as part of the International Ocean Discovery Program. Onshore, some of the current project’s investigators have already documented a number of the existing conditions where sampling took place.

Map of the Costa Rica convergent margin showing the location of active volcanoes, previously investigated hot springs (with associated temperatures) and ODP/IODP archival cores. Credit: Josh Wood/DCO Engagement Team

Opportunity for new understanding
Carbon is stored in ocean sediments, as well as in Earth’s mantle and crust. Each of these “storage areas” serves as a carbon reservoir. Carbon flux is the term for carbon movement between reservoirs. Many questions exist about the influence of biological processes on carbon flux. This investigation will help scientists better predict how carbon moves in and out of Earth on a global basis and how that movement is related to biological processes.
Because this project is exploratory, it will improve what we know about how carbon moves, but also is offering vast opportunities for surprising new discoveries. Another unique aspect is that the lead investigators are early career scientists (within seven years of being awarded a PhD), who have aligned themselves with a strong collection of external collaborators, many of whom are leaders in their field. What this team learns will inform the field of deep carbon science for years to come.

Research Plan 

Volcanologist Tobias Fischer (University of New Mexico, USA) samples gases emitted from a sulfur-caked fumarole on Poás volcano in Costa Rica, one of the 15 volcanoes in DCO’s DECADE gas monitoring network. Credit: Raúl Mora-Amador and Carlos Ramírez U, University of Costa Rica.

The team visited 25 field sites over the course of 12 days: Poás, Turrialba, and Arenal volcanoes and springs along the Nicoya and Osa peninsulas. Costa Rican scientists will play integral roles in the logistic and scientific success of the field campaign, with Carlos Ramirez from the University of Costa Rica leading the charge. The local team also includes Gino Gonzalez from the University of Costa Rica, and J. Maarten de MoorMaria MartinezMonserrat Cascante, and Ricardo Sanchez from the Observatorio Vulcanológico Y Sismológico de Costa Rica, Universidad Nacional, Costa Rica  (OVSICORIO-UNA)). Together, the local and international team of investigators conducted different sampling protocols at each of the locations, as described below.
Going deeper: On site sampling
Principal Investigator Peter Barry (University of Oxford, UK) and collaborator Patrick Beaudry (Massachusetts Institute of Technology, USA) collected fluid and gas samples in the forearc and arc to distinguish biogenic, thermogenic, and abiotic carbon sources.  
Donato Giovanelli (Earth-Life Science Institute, Japan and Rutgers University, USA) and Karen Lloyd (University of Tennessee, USA) led a team of collaborators that includes Lloyd’s graduate student Katie Fullerton, as well as collaborator Heather Miller (Michigan State University, USA). They combined in situ measurements of biologically relevant geochemistry and metabolic activity with ex situ biochemical and molecular tools to investigate the functional and taxonomic diversity of the microbial community within sediments and fluids in the volcanic arc and forearc.
Daniel Hummer (Southern Illinois University, USA) and J. Marteen de Moor (Universidad Nacional, Costa Rica), Angelo Battaglia (Università degli Studi di Palermo, Italy), Giulio Bini (University of Florence, Italy), and Kayla Iocovino (Arizona State University, USA) measured the complete chemical composition of gases from actively degassing volcanoes using a combination of direct measurement and in situ sampling. Taryn Lopez (University of Alaska Fairbanks, USA) spearheaded this part of the sampling plan and was unable to join the team in the field, but will remain heavily involved in the project moving forward. 
Hummer and de Moor, with collaborators Esteban Gazel and Aristides Alfaro (Virginia Tech, USA),  sampled volcanic tephras (solid matter, such as ash, dust, and cinders, that is ejected into the air by an erupting volcano) from Turrialba, Poás, and Arenal volcanoes, which contain abundant olivine phenocrysts with melt and fluid inclusions.
Collaborator Stephen Turner  (Washington University in St. Louis, USA) used sophisticated analytical methods to track fluxes from the slab to the mantle wedge, helping to delineate volatile sources and the proportion of deeply recycled carbon. Kayla Iocovino is working to create a box model describing carbon flux at this convergent margin. 
Katie Pratt (University of Rhode Island, USA) documented the expedition, blogging from the field and photographing and filming the team in action. Videographers Marcus Lehmann, Brian Cimaglia, Russ Hollingsworth, and Tom Owens, also joined the expedition and are creating short films about this novel field investigation.
Additional collaborators not participating in the field, but involved in data and sample analysis, include Mustafa Yucel, Matt Schrenk, Shuhei Ono, Rosario Esposito, David Hilton, Christopher House, Amanda Martino, Elena Manini, Constantino Vitriani, Tomohiro Mochizuki, Mayukpo Nakagawa, and Francesco Regoli.
Since the sampling expedition is now complete, investigators are sharing samples and conducting additional analyses in many laboratories around the globe. The team expects to report out their results in spring 2018.  Check back here as the results unfold.

Expedition Scientists (Peter Barry)
University of Oxford, UK

Karen Lloyd
University of Tennessee, USA

Donato Giovannelli
Earth-Life Science Institute, Japan
and Rutgers University, USA

Daniel Hummer
Southern Illinois University, USA

Taryn Lopez
University of Alaska, USA

J. Maarten de Moor
Universidad Nacional, Costa Rica

Katie Pratt
University of Rhode Island, USA

Research Team

  • Aristides Alfaro
    Virginia Tech, USA

  • Joy Buongiorno
    University of Tennessee, USA

  • Monserrat Cascante
    OVSICORI-UNA, Costa Rica

  • Rosario Esposito
    University of California, Los Angeles, USA

  • Esteban Gazel
    Virginia Tech, USA

  • Maria Martinez
    OVSICORI-UNA, Costa Rica

  • Raúl Mora
    University of Costa Rica

  • Shuhei Ono
    Massachusetts Institute of Technology, USA

  • Rita Parai
    Washington University in St. Louis, USA

  • Carlos Ramirez
    University of Costa Rica, Costa Rica

  • Francesco Regoli
    Polytechnic University of Marche, Italy

  • Matt Schrenk
    Michigan State University, USA

  • Stephen Turner
    Washington University in St. Louis, USA

  • Lorena Uribe
    University of Costa Rica, Costa Rica

  • Mustafa Yucel
    Middle East Technical University, Turkey

  • José Zuñiga
    OVSICORI-UNA, Costa Rica


24 February 2017
Darlene Trew Crist, University of Rhode Island, USA 

Over a two-week span in February, 20 early career investigators sampled 25 different volcanic and hot spring sites in the Costa Rican volcanic arc


A video that provides a bird's eye view of the expedition is here: Some of the scientists explain their field work here

14 February 2017
Darlene Trew Crist, University of Rhode Island, USA 

The team has arrived!  Daily reports on their progress can be found here

1 November, 2016
Katie Pratt, University of Rhode Island, USA

Turrialba’s eruption continues (November 2017), with columns of ash and gas up to 1km high. Credit: Gino Gonzáles-Ilama.

Members of the Biology Meets Subduction team are currently planning their field expedition. A team of approximately 25 scientists, led by the seven early career scientists who proposed the project, will head to Costa Rica on 11 February 2017.
The expedition will focus on the warm and hot springs of the Nicoya peninsula, as well as active volcanoes north of the capital San José. With Turrialba volcano currently erupting, the team is modifying their sampling route for safety reasons and to avoid travel disruptions.
The team is focused at the moment on finalizing personnel and ordering the necessary equipment for the field. They are also working with videographer David Fine to finalize plans for their short documentary.
Thanks to previous field campaigns by various team members in Costa Rica, contacts made during the 2014 DCO Early Career Scientist Workshop, and co-PI Maarten de Moor’s current position at the National University in Costa Rica, the team is already making huge progress in terms of logistical planning.

Further Reading

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Header image: Overlooking Turrialba volcano in Costa Rica. Credit: Katie Pratt