A deeper look at carbon

We hear a lot about rising levels of carbon dioxide in Earth’s atmosphere and how human activities are making a difference. But is there more to carbon's story?

Surprisingly, a whopping 90 percent of all carbon in Earth is contained in the planet’s crust, mantle, and core. It’s deep carbon, the carbon of diamonds and volcanoes, and it affects our lives.

We don’t where all the carbon is, what forms it takes or how it moves around.

A research collection from geologists, chemists, physicists and biologists provides new knowledge on Earth’s carbon cycle. Selected as a 2018 Spotlight finalist, Deep Carbon in Earth: Early Career Scientist Contributions to the Deep Carbon Observatory helps decipher the consequences of anthropogenic carbon emissions, offers clues for sequestering carbon dioxide underground, provides insights into volcanic eruptions — and may even inform the search for extraterrestrial life.

This multidisciplinary research topic is making an impact in the deep carbon community, sparking vigorous discussions. The collection has already received 40,000 views, 4,300 article downloads and a number of citations.

Dr Donato Giovannelli, a microbial ecologist, explains why he teamed up with biogeochemist Dr Alysia Cox, microbiologist Dr Cody Sheik and geologist Dr Benjamin Alexander Black to launch this Research Topic, as well as some of its outcomes and what winning the 2018 Frontiers Spotlight Award would mean for the deep carbon science field.

Why was this Research Topic created?

The carbon cycle encompasses chemistry, physics, geology and biology — yet until recently, most research into Earth’s deep carbon was disjointed. “There was little communication between scientists working in different fields,” says Giovannelli.

This changed in 2009 with the creation of the Deep Carbon Observatory: a 10-year, multidisciplinary collaboration on how the deep-carbon cycle drives our world.

“The realization that disparate disciplines must work together and create a holistic view of Earth’s carbon cycle was a turning point for the field,” says Giovannelli. “An example is geomicrobiology, where scientists are now integrating information on rock formation, rock age, mineralogy, genomics and geochemistry to answer new questions about how life thrives in the subsurface.”

He and his colleagues saw that a new generation of scientists is at the forefront of this interdisciplinary approach — and that they needed a way to highlight their innovative work.

“Very few journals are capable of handling this type of endeavor,” explains Giovannelli. “Given the number of disciplines Frontiers covers, we felt a Research Topic was a natural choice to showcase the interconnected perspectives of early career scientists across the deep-carbon community.”

What type of research is included?

The articles in the research collection span from petrology to geochemistry to microbiology, “an unconventional and, we hope, forward-looking approach,” says Giovannelli.


Several investigate different forms of carbon — gaseous, liquid and solid — in underground rocks and the Earth’s mantle, and how these change under different conditions.

Others look at interactions between life and carbon. A number focus on microbes living deep underground and on the ocean floor. Unraveling how these microbes use carbon dioxide and methane gives insights into how the carbon cycle interacts with other biogeochemical cycles — and may give clues about where and how to look for life on other planets and moons.

One novel study uses models of continental plate movement to calculate coastal over the past 65 million years. The authors then use this to estimate seagrass habitat over this long timescale, and hence the role of seagrass meadows in carbon sequestration.

What are some outcomes of this Research Topic?

The editors are proud of the significant contribution made by the different articles to their respective fields.

Two, for example, show that most carbon dioxide degassing from volcanoes comes not from their main crater, as had been thought, but along their flanks and from major fractures. Interestingly, degassing patterns change in the period leading up to an eruption — and so could serve as an early warning sign.

Several are also relevant to climate change.

“Understanding the Earth’s natural carbon cycle can help decipher the consequences of anthropogenic carbon emissions — and offer clues to addressing ongoing emissions,” says Giovannelli. “One article found that serpentinite might be a good host rock for carbon dioxide sequestration.”

Beyond specific findings, the articles also showcase the power of working in highly interdisciplinary teams.

“It’s wonderful to see the articles being accessed, cited and discussed,” says Giovannelli.

Why should this Research Topic win the 2018 Spotlight Award?

“Being selected as a winner would be outstanding for the up-and-coming scientists who contributed to our Research Topic,” says Giovannelli.

“A conference would be a game-changer,” he continues. “It would help so many more young scientists jump-start their careers by providing a forum to present their work and network across and beyond their own discipline boundaries.”

With a central theme of carbon and its quantities, movements, forms, and origins on Earth, the conference would also build on previous events organized by the Deep Carbon Observatory.

“This Research Topic was envisioned at a workshop in 2015,” explains Giovannelli. “It would be wonderful to go full circle and organize a follow-up meeting on major advances from the past four years — and more importantly, build new interdisciplinary networks among the ever-growing deep-carbon community and spur new research on Earth’s deep carbon cycle.”

About the Frontiers Spotlight Award

The annual Frontiers Spotlight Award supports emerging and important fields of research published as a Research Topic in Frontiers journals. The winning team of Topic Editors receives US$100,000 to organize an international scientific conference on the theme of their successful Research Topic. Learn more about the Award

About Frontiers Research Topics

Research Topics are peer-reviewed article collections published around specialized themes. They bring together leading researchers from different institutions, locations and fields of interest, who collaborate and contribute articles.

Published on Frontiers’ award-winning platform, Research Topics are fully open and accessible, and become highly visible collections of work, enhancing both the readership and citations of articles. Learn more about Research Topics

How to enter

Every Research Topic that closes within the award period and is completed with at least 10 articles, will be considered for the Spotlight Award. Shape your field and have the chance to organize your own conference — suggest your Research Topic today!

Spotlight Award_2018_Infographics_Deep carbon.png

Research Topic Editors

Donato Giovannelli   Earth-Life Science Institute, Japan

Donato Giovannelli
Earth-Life Science Institute, Japan

Alysia Cox   Montana Technological University, USA

Alysia Cox
Montana Technological University, USA

Cody Sheik   University of Minnesota Duluth, USA

Cody Sheik
University of Minnesota Duluth, USA

Benjamin Alexander Black   City College of New York, USA

Benjamin Alexander Black
City College of New York, USA