C-DEBI Newsletter – September 1, 2016

Publications

Lithos
Sulfur and carbon geochemistry of the Santa Elena peridotites: Comparing oceanic and continental processes during peridotite alteration
Esther M. Schwarzenbach*, Benjamin C. Gill, Esteban Gazel, Pilar Madrigal
*C-DEBI Contribution 334

Ultramafic rocks exposed on the continent serve as a window into oceanic and continental processes of water–peridotite interaction, so called serpentinization. In both environments there are active carbon and sulfur cycles that contain abiogenic and biogenic processes, which are eventually imprinted in the geochemical signatures of the basement rocks and the calcite and magnesite deposits associated with fluids that issue from these systems. Here, we present the carbon and sulfur geochemistry of ultramafic rocks and carbonate deposits from the Santa Elena ophiolite in Costa Rica. The aim of this study is to leverage the geochemistry of the ultramafic sequence and associated deposits to distinguish between processes that were dominant during ocean floor alteration and those dominant during low-temperature, continental water–peridotite interaction.

The peridotites are variably serpentinized with total sulfur concentrations up to 877 ppm that is typically dominated by sulfide over sulfate. With the exception of one sample the ultramafic rocks are characterized by positive δ³⁴S_sulfide (up to + 23.1‰) and δ³⁴S_sulfate values (up to + 35.0‰). Carbon contents in the peridotites are low and are isotopically distinct from typical oceanic serpentinites. In particular, δ¹³C of the inorganic carbon suggests that the carbon is not derived from seawater, but rather the product of the interaction of meteoric water with the ultramafic rocks. In contrast, the sulfur isotope data from sulfide minerals in the peridotites preserve evidence for interaction with a hydrothermal fluid. Specifically, they indicate closed system abiogenic sulfate reduction suggesting that oceanic serpentinization occurred with limited input of seawater. Overall, the geochemical signatures preserve evidence for both oceanic and continental water–rock interaction with the majority of carbon (and possibly sulfate) being incorporated during continental water–rock interaction. Furthermore, there is evidence for microbial activity that was possibly stimulated by carbon sourced from water–rock interaction with adjacent sediments or fluid inclusions. This study provides detailed insight into the complex hydrothermal history of continental serpentinization systems and adds to our understanding of the carbon and sulfur cycling within peridotite-hosted hydrothermal systems.

Education & Outreach

Spotlight: Paul Karim, 2016 CC-RISE Intern
With the Fisher Hydrogeology Group at UCSC, C-DEBI CC-Rise Intern Paul Karim is working on a project to enhance groundwater conditions by increasing the input of surface waters (groundwater recharge) and improving water quality by stimulating microbial removal of nitrogen (denitrification) in shallow soil. This work is a collaboration with the Resource Conservation District of Santa Cruz County. Check out this C-DEBI spotlight feature for more details and photos!

Delaware Sea Grant’s first 15-second C-DEBI Science Videos!
These videos are supported by a C-DEBI E&O Grant to build a collection of short, introductory videos using multimedia that can be broadcast on webpages, utilized in presentations and classroom lessons, and shared via social media. Through these easily digestible episodes and longer, in-depth features, DE Sea Grant will provide widely usable content for the entire C-DEBI community, classroom and informal educators, and the science-interested/curious public.

Proposal Calls

DCO: Census of Deep Life Sequencing Opportunities
Since 2011, the Deep Carbon Observatory’s Deep Life Community has sponsored the Census of Deep Life (CoDL) that has supported surveys of the diversity of microbes present in several deep continental and subseafloor environments. The first surveys (2011-2012) were conducted using 454 pyrosequencing and subsequently (2013) Illumina sequencing strategies were adopted. Through this initiative, the Deep Life Community has allowed the characterization of diversity of subsurface microbial communities at numerous sites worldwide including the subseafloor and deep continental locations from a range of geologic settings (e.g., large igneous provinces, subglacial lakes, methane hydrate-rich sediments, cratons). The Illumina platform provides increased numbers of reads for more samples at reduced cost. For DNA samples submitted to the CoDL for sequencing, proponents have the option of obtaining 400-450 nt bacterial sequences that span the V4V5 region of Bacterial and Archaeal rRNA coding regions or a greater number of reads for V6 regions that through complete overlap of forward and reverse reads allows detection of lower abundance taxa with reduced stochastic error rates. Shotgun metagenomic DNA sequencing for key samples can also be performed. This call for proposals aims to support sequencing that represents expanded analyses from ongoing Deep Life Community projects or projects that represent sites and investigators new to the DCO’s Deep Life Community. Deadline: September 15, 2016.

NSF: Integrated Earth Systems (IES) Program Solicitaiton
The Earth consists of a variety of complex systems that are variable over space and time, and respond to a wide range of perturbations. The goal of the Integrated Earth Systems (IES) program is to investigate the interplay among the continental, terrestrial, and interior systems of the planet. The program provides an opportunity for collaborative, multidisciplinary research into the operation, dynamics, and complexity of Earth systems that encompass the core of the Earth through the surface. Innovative projects that explore new research directions beyond those typically considered by core programs of the Division of Earth Sciences (EAR) are encouraged. Investigations may include all or part of the continental, terrestrial and deep Earth at all temporal and spatial scales. IES will support topics that include (but are not limited to) continental systems; terrestrial or surficial Earth systems including physical, chemical, and biotic dimensions; linkages among tectonics, climate, and landscape evolution; the coupling of the Earth’s climate, depositional and biotic systems; and global cycles that involve core and mantle processes. We anticipate 4 to 10 new awards per year. The award size for IES projects can be up to $3,000,000 with a duration of up to 5 years, but proposals for smaller awards or duration are welcome. Full proposal deadline: November 14, 2016.

NSF: Call For Nominations for the Alan T. Waterman Award
Complete nomination packages, consisting of nominations and four letters of reference, are due by October 21, 2016.

IODP-USSSP: Apply to Sail

• Expedition 372, Creeping Gas Hydrate Slides and Hikurangi LWD, November 2017 – January 2018
  Application deadline: October 1, 2016
• Expedition 375, Hikurangi Subduction Margin, March – May, 2018
  Application deadline: October 1, 2016

IODP-USSSP: Proposals for Pre-Drilling Activities and Workshops
The U.S. Science Support Program (USSSP) accepts proposals on a rolling basis for pre-drilling activities and semi-annually for workshops, related to the International Ocean Discovery Program (IODP).

Employment

University of Calgary: Four Postdoctoral Research Associate Vacancies
The Energy Bioengineering and Geomicrobiology (EBG) group at the University of Calgary has several vacancies for postdoctoral research associates to join projects on a range of fundamental and applied aspects of environmental microbiology. All applications due September 23, 2016. Positions available now:

• PDRA in Geomicrobiology (Job ID: 11117): Studying the physiology of thermophilic spore forming anaerobes found in cold sediments including temperature physiology, germination and sporulation.
• PDRA in Molecular Microbial Ecology (Job ID: 11118): Quantitatively mapping microbial anomalies in marine sediments in the vicinity of seabed petroleum seeps, including hydrocarbon-degrading bacteria
• PDRA in Biogeochemistry (Job ID: 11119 ): Developing activity assays for marine microbial processes including sulphate reduction (using radiotracer) and hydrocarbon biodegradation (using GC MS)
• PDRAin Microbial Diversity & Metagenomics (Job ID: 11120 ): Understanding the microbiomeof pristine Arctic marine habitats (sea ice, sea water, sediments) to establish new baselines for environmental monitoring

C-MORE: Microbial Genomics Software Engineer
Develops software and hardware solutions for management, access, and analyses on very large microbial genomic/transcriptomic sequence datasets.  Develops standardized workflows and solutions for data visualization and publication.  Develops software solutions for the high throughput analysis of large deoxyribonucleic acid (DNA), ribonucleic acid (RNA) and protein sequence datasets, and associated genomic data and metadata.  Maintains computer systems for the high throughput analysis of large DNA, RNA, and protein sequence datasets.  Maintains databases and specialized software applications for metagenomic and metatranscriptomic microbial oceanographic studies.  Assists Principal Investigator; supervises graduate students and laboratory staff in the use of computational tools, statistical analyses, workflows, and visualization tools for analyses of microbial genomic and metagenomic data.  Job requires onsite presence at the University of Hawaii, Manoa. Send inquiries to: edelong@hawaii.edu. If interested in applying, Please go to www.rcuh.com, click on “Employment”; select “Apply” and navigate to “See Job Announcements and/or Apply for a Job.”  Job ID# 16439. Please apply before: September 12, 2016.

USC / C-DEBI: Full-time Diversity Specialist
Review of applications begins: August 19, 2016.

University of New Hampshire: Associate or Full Professor of Estuarine Science
Review of applications: August 15, 2016 until position filled.

Moore Foundation: Program Fellow, Marine Microbiology Initiative