Media Highlights

Integrative Programs Program Director (Rotator) within the Division of Ocean Sciences (OCE)

Posted: May 12, 2022

The Integrative Programs Section within the Division of Ocean Sciences (OCE) in the Directorate of Geosciences (GEO) announces a nationwide search for a Program Director (Rotator) with experience and expertise in the general fields of marine geology, marine geophysics, paleoceanography, marine geochemistry, marine geobiology, or scientific ocean drilling. The Ocean Drilling Program (ODP) provides oversight of the award supporting operations of the JOIDES Resolution drillship facility, the primary U.S. contribution to the International Ocean Discovery Program (IODP). The Program Director’s core duties and responsibilities will be assisting in administering the current ODP awards and in assisting the provision of leadership and coordination in IODP and other U.S. and international scientific ocean drilling efforts, as well as in coordinating and working with other programs in NSF and other Federal agencies and organizations.

Source: https://beta.nsf.gov/careers/openings/geo/oce/oce-2022-48020

Open Rank Faculty Search Rosenstiel School of Marine and Atmospheric Sciences

University of Miami

Posted: September 15, 2021

The Rosenstiel School in Marine and Atmospheric Science at the University of Miami (UM) seeks to expand its vibrant intellectual community through inviting applications within a cluster hiring initiative to appoint up to five tenured or tenure-track faculty members, one per Department, who meet the following qualifications: Faculty who would bring visibility, renown, and additional impact to any of the five individual RSMAS Departments in Atmospheric Sciences, Ocean Sciences, Marine Geosciences, Marine Biology and Ecology, or Environmental Science and Policy; Faculty who would add to the long-standing goal of increasing diversity across our departments. Applications will be considered at the Assistant Professor, Associate Professor, and Professor ranks.

Source: https://umiami.wd1.myworkdayjobs.com/en-US/UMFaculty/job/Miami-FL/Open-Rank-Faculty-Search-Rosenstiel-School-of-Marine-and-Atmospheric-Sciences_R100050400

Earth Science Women's Network

Earth and Environmental Science Jobs List

Posted: August 16, 2021

The Earth and Environmental Science Jobs List is now co-hosted by the Earth Science Women’s Network! This crowd-sourced list includes pages for Tenure Track/Permanent jobs, Non-Tenure Track Faculty, and Postdoc positions. Graduate student positions are co-moderated by Geoscience Education Mentoring Support (GEMS).

Source: https://eswnonline.org/online/earth-and-environmental-science-jobs/

Postdoctoral Position(s) in Fluid-Rock Interactions & Investigation of Deep Subsurface Life

University of Toronto

Posted: August 13, 2021

Water-rock reactions supporting the deep subsurface biosphere by producing electron donors and acceptors in the subsurface have been identified, from serpentinization (mineral hydration reactions), to radiogenic reactions. In the Stable Isotope Laboratory of Dr. Barbara Sherwood Lollar, this project focuses on the potential for a radiolytically driven H, S, and C deep cycle in the Earth’s subsurface, and the reaction mechanisms and rates sustaining deep subsurface microorganisms in the absence of interaction with the surface photosphere. The Earth-based focus on this work will have direct relevance for models of planetary habitability capable of sustaining subsurface chemolithotrophic life on planets or moons where photosynthesis may never have arisen. Field, laboratory and modelling opportunities are available to extend the existing program to explore the implications of our work on Earth analogs to the search for life on the rocky bodies and ocean worlds of our solar system.

Source: https://bsherwoodlollar.weebly.com/research-opportunities.html

Meetings and Activities

Center for Dark Energy Biosphere Investigations

Virtual Meeting Series Archive: The Many Ways to Use Anvi’o, a Platform for Microbial ‘Omics

Posted: June 17, 2022

Did you miss the last VMS on The Many Ways to Use Anvi’o, a Platform for Microbial ‘Omics? Check out the recording with invited speaker Iva Veseli (University of Chicago) as she introduces Anvi’o, a community-driven software platform enabling integrated analyses and interactive visualization of multi-’omic data, and discusses the various ways to learn and use anvi’o, and how these strategies fit different research needs and users with different levels of computational experience.

Source: https://www.darkenergybiosphere.org/outputs-resources/previous-virtual-meetings/

Meetings and Activities

Center for Dark Energy Biosphere Investigations

Virtual Meeting Series Archive: Sampling Oceanic Crustal Fluids

Posted: March 5, 2022

Did you miss the last VMS on Sampling Oceanic Crustal Fluids: Some Options? Check out the recording with invited speakers Rika Anderson (Carleton College), Julie Huber (Woods Hole Oceanographic Institution), Susan Lang (University of South Carolina), and Michael Rappé (University of Hawaii) as they discuss the many different types of samplers including those available for sampling hydrothermal fluids with submersibles, and the costs and benefits of the different approaches.

Source: https://www.darkenergybiosphere.org/outputs-resources/previous-virtual-meetings/

Steve D'Hondt on Reviving a 100-Million-Year-Old Bacterial Colony

Geology Bites

Posted: August 16, 2021

Steve D’Hondt is Professor of Oceanography at the University of Rhode Island. He studies life beneath the sea floor, and was a part of the team that discovered bacterial cells living in 100-million-year-old sediment. He explains how the bacteria managed to eke out a living for such a long time with barely any access to nutrients.

Source: https://www.geologybites.com/steve-dhondt

Study examines role of deep-sea microbial predators at hydrothermal vents

Posted: August 13, 2021

Hydrothermal vent fluids from the Gorda Ridge spreading center in the Pacific Ocean create a biological hub of activity in the deep sea. There in the dark ocean, a unique food web thrives not on photosynthesis but on chemical energy from the venting fluids. Among the creatures having a field day is a diverse assortment of microbial eukaryotes, or protists, that graze on chemosynthetic bacteria and archaea. This protistan grazing, a key mechanism for carbon transport and recycling in microbial food webs, exerts a higher predation pressure at hydrothermal vent sites than in the surrounding deep-sea environment, a U.S. National Science Foundation-funded paper reports. “Our findings provide a first estimate of protistan grazing pressure in hydrothermal vent food webs, highlighting the important role diverse protistan communities play in deep-sea carbon cycling,” according to the paper in Proceedings of the National Academy of Sciences.

Source: https://www.nsf.gov/discoveries/disc_summ.jsp?WT.mc_id=USNSF_1&cntn_id=303191

How an ill-fated undersea adventure in the 1960s changed the way scientists see the Earth

Vox

Posted: March 17, 2021

There’s a mystery hiding deep beneath our feet. If you dig down past the tree roots and house foundations, past the water table and the fossilized bones, through layers of rock and ore, you’ll eventually reach a boundary. Here, the Earth’s crust — the rock we live our lives on — transitions into the denser rock of the Earth’s mantle. This boundary is the Mohorovičić discontinuity, or “Moho” for short. And no one knows for sure what this boundary looks like, or what lies there. Hear more in the Unexplainable podcast episode “Journey Toward the Center of the Earth” with Byrd Pinkerton.

Source: https://www.vox.com/unexplainable/22276597/project-mohole-deep-ocean-drilling-unexplainable-podcast

What the deep ocean can teach us about life

BBC

Posted: March 15, 2021

In this BBC Earth Podcast, we’re exploring the parts of our world that require us to look a little deeper. From the depths of our oceans to the canopies that grace our skylines, we’ll be venturing into unfamiliar pockets of nature with the people who have carved a life out of choosing to study the things that many of us can’t see. We also travel to the bottom of the ocean, and discover how even in the most extreme environments fragments of life persist. What can this alien environment teach us about life’s limits and extraordinary capabilities? C-DEBIer James Bradley talks about the deep biosphere and the findings of his recent Science Advances paper.

Source: https://play.acast.com/s/bbcearthpodcast/whatthedeepoceancanteachusaboutlife

100-Million-Year-Old Seafloor Sediment Bacteria Have Been Resuscitated

Scientific American

Posted: March 4, 2021

The evidence mounts that bacteria can be effectively immortal. Featuring the Integrated Ocean Drilling Program’s Expedition 329 to the South Pacific Gyre. By Jennifer Frazer on March 4, 2021.

Source: https://www.scientificamerican.com/article/100-million-year-old-seafloor-sediment-bacteria-have-been-resuscitated/

IODP U.S. Science Support Program

Pre-Drilling Activities

Posted: May 17, 2022

The U.S. Science Support Program sponsors Pre-Drilling Activities to provide funds in quick response to an opportunity to acquire data or information that will enhance a drilling expedition. Priority is given to projects that support expeditions already on the ship’s schedule. The definition of this activity is deliberately flexible to allow consideration of exceptional or unusual requests for drill site data enhancement.

Source: https://usoceandiscovery.org/pre-drilling-activities/

Division of Ocean Sciences (OCE)

Posted: May 17, 2022

Within the Directorate for Geosciences (GEO), the Division of Ocean Sciences supports research, infrastructure, and education to advance understanding of all aspects of the global oceans and ocean basins, including their interactions with people and the integrated Earth system. These activities provide knowledge critical to addressing many of our nation’s most pressing challenges involving earth processes. OCE supports and promotes collaboration and facilitates development of a diverse scientific and educational community, including international efforts. The Division works with the U.S. ocean sciences academic community to direct funding towards advancing the frontiers of knowledge, developing the next generation of researchers, and enhancing the public’s understanding of ocean sciences. The Division represents this community in the Federal context, coordinates with other Federal agencies and with international partners on research funding and infrastructure management, and participates in development of policy through national and international forums and programs.

Source: https://nsf.gov/funding/programs.jsp?org=OCE

NASA

Exobiology

Posted: May 17, 2022

The goal of NASA’s Exobiology program (formerly Exobiology and Evolutionary Biology) is to understand the origin, evolution, distribution, and future of life in the Universe. Research is centered on the origin and early evolution of life, the potential of life to adapt to different environments, and the implications for life elsewhere. This research is conducted in the context of NASA’s ongoing exploration of our stellar neighborhood and the identification of biosignatures for in situ and remote sensing applications.

Source: https://astrobiology.nasa.gov/research/astrobiology-at-nasa/exobiology/

Pathways into the Earth, Ocean, Polar and Atmospheric & Geospace Sciences (GEOPAths)

Posted: February 2, 2022

The Directorate for Geosciences (GEO) supports the Pathways into the Geosciences – Earth, Ocean, Polar and Atmospheric Sciences (GEOPAths) funding opportunity. GEOPAths invites proposals that specifically address the current needs and opportunities related to education, learning, training and professional development within the geosciences community through the formation of STEM Learning Ecosystems that engage students in the study of the Earth, its oceans, polar regions and atmosphere. The primary goal of the GEOPAths funding opportunity is to increase the number of students pursuing undergraduate and/or postgraduate degrees through the design and testing of novel approaches that engage students in authentic, career-relevant experiences in geoscience. In order to broaden participation in the geosciences, engaging students from historically excluded groups or from non-geoscience degree programs is a priority.

Source: https://www.nsf.gov/pubs/2022/nsf22555/nsf22555.htm

Cruise Opportunity Program

UNOLS

Posted: June 27, 2019

The primary goal of the UNOLS Cruise Opportunity Program is to provide graduate students currently completing (or who have recently completed) a degree in a field of oceanographic research with the opportunity to participate in a research cruise. The participant will be a member of the scientific party and be involved in data collection and all other activities at sea. It is envisioned that the individual will be familiar with the science to be conducted at sea, and thus, form new collaborations and potentially develop new research directions. To be eligible to participate in this program, the individual must be either currently be studying at a U.S.-based institution or a recent graduate, and must have either a U.S. Passport or a U.S. Work Visa. Please note that you are responsible for paying for your travel to/from the ship (unless otherwise noted), and at this time the UNOLS Office is unable to provide travel funds; however your advisor or institution may have some ideas.

Source: https://www.unols.org/unols-cruise-opportunity-program

Quantifying the Bioavailable Energy in an Ancient Hydrothermal Vent on Mars and a Modern Earth-Based Analog

Astrobiology

Authors: Holly R. Rucker, Tucker Ely, Douglas E. LaRowe, Donato Giovannelli, Roy E. Price

Published: April 1, 2023

C-DEBI Contribution Number: 615

Abstract

Putative alkaline hydrothermal systems on Noachian Mars were potentially habitable environments for microorganisms. However, the types of reactions that could have fueled microbial life in such systems and the amount of energy available from them have not been quantitatively constrained. In this study, we use thermodynamic modeling to calculate which catabolic reactions could have supported ancient life in a saponite-precipitating hydrothermal vent system in the Eridania basin on Mars. To further evaluate what this could mean for microbial life, we evaluated the energy potential of an analog site in Iceland, the Strytan Hydrothermal Field. Results show that, of the 84 relevant redox reactions that were considered, the highest energy-yielding reactions in the Eridania hydrothermal system were dominated by methane formation. By contrast, Gibbs energy calculations carried out for Strytan indicate that the most energetically favorable reactions are CO₂ and O₂ reduction coupled to H₂ oxidation. In particular, our calculations indicate that an ancient hydrothermal system within the Eridania basin could have been a habitable environment for methanogens using NH₄⁺ as an electron acceptor. Differences in Gibbs energies between the two systems were largely determined by oxygen—its presence on Earth and absence on Mars. However, Strytan can serve as a useful analog for Eridania when studying methane-producing reactions that do not involve O₂.

Source: http://dx.doi.org/10.1089/ast.2022.0064

Evolutionary diversification of methanotrophic ANME-1 archaea and their expansive virome

Nature Microbiology

Authors: Rafael Laso-Pérez, Fabai Wu, Antoine Crémière, Daan R. Speth, John S. Magyar, Rui Zhao, Mart Krupovic, Victoria J. Orphan

Published: January 19, 2023

C-DEBI Contribution Number: 611

Abstract

‘Candidatus Methanophagales’ (ANME-1) is an order-level clade of archaea responsible for anaerobic methane oxidation in deep-sea sediments. The diversity, ecology and evolution of ANME-1 remain poorly understood. In this study, we use metagenomics on deep-sea hydrothermal samples to expand ANME-1 diversity and uncover the effect of virus–host dynamics. Phylogenetic analyses reveal a deep-branching, thermophilic family, ‘Candidatus Methanospirareceae’, closely related to short-chain alkane oxidizers. Global phylogeny and near-complete genomes show that hydrogen metabolism within ANME-1 is an ancient trait that was vertically inherited but differentially lost during lineage diversification. Metagenomics also uncovered 16 undescribed virus families so far exclusively targeting ANME-1 archaea, showing unique structural and replicative signatures. The expansive ANME-1 virome contains a metabolic gene repertoire that can influence host ecology and evolution through virus-mediated gene displacement. Our results suggest an evolutionary continuum between anaerobic methane and short-chain alkane oxidizers and underscore the effects of viruses on the dynamics and evolution of methane-driven ecosystems.

Source: http://dx.doi.org/10.1038/s41564-022-01297-4

Chemistry of springs across the Mariana forearc: Carbon flux from the subducting plate triggered by the lawsonite-to-epidote transition?

Geochimica et Cosmochimica Acta

Authors: Michael J. Mottl, Thomas M. McCollom, Charles Geoffrey Wheat, Patricia Fryer

Published: January 1, 2023

C-DEBI Contribution Number: 610

Abstract

Low-chlorinity springs sampled from ten sites on nine serpentinite mud volcanoes show systematic chemical gradients across the outer Mariana forearc that result from progressive devolatilization of the subducting Pacific plate. Sites range from 50 to 90 km from the trench axis corresponding to depths to the top of the plate of ∼15–29 km. Dissolved sulfate, Na/Cl, K, Rb, Cs, and B in the springs all increase regularly with distance from the trench, leached from subducting sediment and altered basalt in response to increasing temperature at depth from ∼80 to 350 °C. Sites nearer the trench have high Ca (up to 76 mmol/kg) and Sr, low alkalinity, and pH 10.7, whereas sites farther from the trench have almost no Ca and Sr, alkalinity (some carbonate but mostly hydroxyl) as high as 69 meq/kg, and pH 12.5. Springs with high alkalinity also have high methane (>44 mmol/kg) that feeds sulfate-reducing archaeal communities in the shallow subsurface and macrofauna at the seafloor. These distal springs form chimneys and crusts of CaCO₃, whereas the proximal springs form chimneys of brucite. High alkalinity at the distal sites apparently results from carbonate dissolution at the top of the subducting plate; because serpentinization during ascent generates both high pH and H₂, the resulting dissolved carbonate is reduced to methane such that carbonate alkalinity is replaced by hydroxyl alkalinity: 4H₂ + HCO₃^– → CH₄ + 2H₂O + OH^–. This reaction can account for the much higher pH of the distal springs. Chlorinity of the springs varies from 234 to 546 mmol/kg and is related to latitude N–S rather than distance from the trench. Distal springs have otherwise similar compositions over this entire range of chlorinity, implying that chloride derives from depth rather than from mixing with seawater within the seamounts themselves. The range in chlorinity can readily be explained by serpentinization at reasonable water/rock mass ratios of 0.2–1.0 if 30–40% of the spring water originates as residual pore water in subducted sediment and basalt rather than as H₂O⁺ of dehydration.

The pH, alkalinity, and methane content of the springs increase abruptly, while Ca and Sr decrease, because carbonate dissolution joins dehydration as a major process at the top of the subducting plate at ∼70 km from the trench, where metabasites recovered from the serpentinite mud indicate the transition from lawsonite blueschist facies to epidote blueschist facies also occurs. Replacement of lawsonite by epidote drastically depletes the solution in Ca and shifts the equilibrium toward massive dissolution of subducted carbonate. Fluxes of sulfate, C, Na, K, Rb, Cs, B, Ca, and Sr in the forearc springs represent only a few percent of the amounts subducted, consistent with continued supply at greater depth.

Source: http://dx.doi.org/10.1016/j.gca.2022.10.029

Transfer efficiency of organic carbon in marine sediments

Nature Communications

Authors: James A. Bradley, Dominik Hülse, Douglas E. LaRowe, Sandra Arndt

Published: November 26, 2022

C-DEBI Contribution Number: 607

Abstract

Quantifying the organic carbon (OC) sink in marine sediments is crucial for assessing how the marine carbon cycle regulates Earth’s climate. However, burial efficiency (BE) – the commonly-used metric reporting the percentage of OC deposited on the seafloor that becomes buried (beyond an arbitrary and often unspecified reference depth) – is loosely defined, misleading, and inconsistent. Here, we use a global diagenetic model to highlight orders-of-magnitude differences in sediment ages at fixed sub-seafloor depths (and vice-versa), and vastly different BE’s depending on sediment depth or age horizons used to calculate BE. We propose using transfer efficiencies (T_eff’s) for quantifying sediment OC burial: T_eff is numerically equivalent to BE but requires precise specification of spatial or temporal references, and emphasizes that OC degradation continues beyond these horizons. Ultimately, quantifying OC burial with precise sediment-depth and sediment-age-resolved metrics will enable a more consistent and transferable assessment of OC fluxes through the Earth system.

Source: http://dx.doi.org/10.1038/s41467-022-35112-9

Globally‐distributed microbial eukaryotes exhibit endemism at deep‐sea hydrothermal vents

Molecular Ecology

Authors: Sarah Hu, Amy R. Smith, Rika E. Anderson, Sean P. Sylva, Michaela Setzer, Maria Steadmon, Kiana L. Frank, Eric Chan, Darlene S.S. Lim, Christopher R. German, John A. Breier, Susan Q. Lang, David A. Butterfield, Caroline S. Fortunato, Jeffrey S. Seewald, Julie A. Huber

Published: November 23, 2022

C-DEBI Contribution Number: 600

Abstract

Single-celled microbial eukaryotes inhabit deep-sea hydrothermal vent environments and play critical ecological roles in the vent-associated microbial food web. 18S rRNA amplicon sequencing of diffuse venting fluids from four geographically- and geochemically-distinct hydrothermal vent fields was applied to investigate community diversity patterns among protistan assemblages. The four vent fields include Axial Seamount at the Juan de Fuca Ridge, Sea Cliff and Apollo at the Gorda Ridge, all in the NE Pacific Ocean, and Piccard and Von Damm at the Mid-Cayman Rise in the Caribbean Sea. We describe species diversity patterns with respect to hydrothermal vent field and sample type, identify putative vent endemic microbial eukaryotes, and test how vent fluid geochemistry may influence microbial community diversity. At a semi-global scale, microbial eukaryotic communities at deep-sea vents were composed of similar proportions of dinoflagellates, ciliates, Rhizaria, and stramenopiles. Individual vent fields supported distinct and highly diverse assemblages of protists that included potentially endemic or novel vent-associated strains. These findings represent a census of deep-sea hydrothermal vent protistan communities. Protistan diversity, which is shaped by the hydrothermal vent environment at a local scale, ultimately influences the vent-associated microbial food web and the broader deep-sea carbon cycle.

Source: http://dx.doi.org/10.1111/mec.16745

2020 SOLID-GEM Course All-Stars

Posted: July 13, 2022

Meet the 2020 summer line up for the Summer OnLine Interactive/Discussion Global Environmental Microbiology (SOLID-GEM) course. We are proud to have been a step in their scientific pathway. Learn more about the GEM course.

Learn more about the GEM course

2019 GEM Course All-Stars

Posted: August 7, 2019

Meet the 2019 summer line up for the Global Environmental Microbiology course. We are proud to have been a step in their scientific pathway. Learn more about the GEM course.

Learn more about the GEM course

2018 GEM Course All-Stars

Posted: August 7, 2019

Meet the 2018 summer line up for the Global Environmental Microbiology course. We are proud to have been a step in their scientific pathway. Learn more about the GEM course.

Learn more about the GEM course