The Deep Carbon Observatory (DCO) as a whole aims to achieve transformational understanding of carbon's chemical and biological roles in Earth's interior. A multidisciplinary, decade-long effort, the DCO consists of a distributed but closely coordinated set of observational efforts and analytical instruments united by shared databases and a commitment to open access. The program leaders have set ambitious global goals, for example, to reduce the range of estimates of total carbon in Earth's mantle from a factor of twenty to a factor of two, to establish the techniques that resolve ambiguities about possible biotic versus abiotic hydrocarbon production, to accomplish the first global 3-D census of deep microbial life (presented in interactive 3-D!), and to produce a comprehensive database of thermochemical properties and speciation of carbon-bearing fluids and phases at the pressure and temperature conditions of the upper mantle. To meet its objectives, the DCO has organized into four "directorates," three of which-Reservoirs and Fluxes, Deep Energy, and Deep Life-have already been funded through previous Foundation grants. This grant to the University of California, Davis will provide partial funding for two years of operations of the DCO's final directorate, concerned with the most basic physics and chemistry of carbon in the extreme conditions of the deep crust and mantle. When we think of basic natural science, we may recall subjects from high school and college courses such as phase diagrams and equations of state. A phase diagram is a type of chart used to show conditions at which thermodynamically distinct phases (such as solid, liquid, or gas) can occur at equilibrium. An equation of state describes a state of matter under a given set of physical conditions such as temperature, pressure, and volume. These are the subjects of the fourth directorate. One reason so little is known about the deep carbon cycle is ignorance of the basic physics and chemistry of carbon at the pressure and temperature conditions of Earth's interior. Even phase diagrams and equations of state do not exist for relevant carbon-bearing fluids and minerals at the prevailing conditions deep inside Earth. Over the next two years, an international team led by University of California, Davis physicist Giulia Galli will make observations, conduct experiments, and build models concerned with thermodynamics of carbon bearing systems in the crust and mantle, dynamics and kinetics of deep carbon processes, and mineral-fluid interactions under extreme conditions. Its results, such as the database of thermochemical properties, will be essential for the other directorates and for the success of the Deep Carbon Observatory as a whole.

Geologists have dreamed of drilling through the Mohorovi?i? discontinuity between Earth's crust and mantle for more than 50 years. Actual rock from this so-called "Mohole" and observations taken along the way could shed light on many of the most fundamental questions about Earth's history and dynamics that more indirect sampling methods, mainly acoustic, have not been able to answer. The acoustic methods, such as "3-D Seismic" are effective means for creating synoptic images (similar to remote sensing by satellite), but just as a satellite cannot sequence the DNA in a plant or animal spied on Earth's surface, so acoustic and other methods cannot specify mineral composition and other crucial aspects of Earth's interior. Samples taken from the Mohold could prove valuable for defining the limits of life in the deepest part of the crust as well as for understanding mantle-crust interactions and other geological questions The prospect of drilling a hole to earth's mantle, however, is daunting. The most likely site, in the Pacific, would require drilling a hole the depth of 14 Empire State Buildings in 10 Empire State Buildings of water. While continental drillers have drilled this deep and ocean drillers have operated in such deep water, the project would involve integrating the two traditions in an unprecedented way. Risks include safety, environment, and finance (One study estimated the total cost of successfully completing the Mohole could exceed $500 million). Funds from this grant will support efforts by the Integrated Ocean Drilling Program to begin the planning and infrastructure development necessary for successfully drilling a borehole to earth's mantle.

This grant to Ohio State University will provide two years of funding for the creation and operation of the Deep Energy directorate of the Deep Carbon Observatory. The third of four directorates that make up the observatory, the Deep Energy directorate will tap an international network of researchers to address one of the most controversial and momentous issues in earth sciences: how to distinguish hydrocarbons, including natural gas and petroleum, which originate from biological materials ("fossil fuels") from those that do not. The Deep Energy team's research agenda aims to develop a fundamental understanding of environments and processes that regulate chemical, mineralogical, and isotopic signatures that could be used to unambiguously differentiate abiogenic from biogenic sources of hydrocarbons. Fifteen scientists from seven countries spanning diverse views form the core team, which is coordinated by a pair of dynamic young researchers, David Cole (Ohio State) and Chris Ballentine (Manchester University, U.K.).

Established in June 2009, the Deep Carbon Observatory (DCO) aims to address two fundamental questions: the origins, abundance, and distribution of hydrocarbons (including so-called fossil fuels) and the origins of life, for which carbon is the key element. The DCO has organized itself into four "directorates", each tasked with executing a different element of the DCO's ambitious research agenda. In October 2010, the Foundation supported the launch of the DCO's first directorate, on deep life. This grant will fund the operation of the second directorate, on deep carbon reservoirs and fluxes. The ambitious aim of the Reservoirs and Fluxes directorate is to integrate, in an unprecedented way, an interdisciplinary group of researchers to study of the upper part of Earth's deep carbon cycle (about 400 kilometers). In a series of simultaneous research projects, the directorate will engage an international group of researchers to conduct fundamental field, laboratory, and modeling research tracing the origin of carbon at the global mid-ocean ridge system, the addition of carbon to oceanic plates, the subduction of carbon at subduction zones, the release of carbon-bearing fluids in the shallow mantle, the delivery of carbon to sources of subduction zone magmatism, and the emission of carbon from convergent margin volcanoes.

The Foundation established the Deep Carbon Observatory (DCO) in 2009 to achieve major advances in understanding of carbon, the element of life, in geologically diverse deep continental and marine environments. The Observatory's plan includes a component whose objective is to describe the types of life that occur, their adaptive and evolutionary strategies, and the limits-and possibly origins-of life. In fact, evidence exists for life in all deep environments where there is liquid water. The environments include oil wells, deep granitic and basaltic aquifers, sandstone cores, clays, gold seams, and deep marine sediments. With Foundation support, an international network of microbiologists and geneticists headquartered at Oregon State University will begin a comprehensive survey of the diversity, distribution, and abundance of life in representative deep environments. Earth's microbes probably amount to 90% or more of all life. The total number of cells might be a nonillion, one thousand times one billion times one billion times one billion, or 10 to the 30th power, and the subsurface biomass may be 90% of all microbial cells. For many environments, however, there are no or sparse data, and the diversity is just now being explored thanks to new gene sequencing technologies. A key technology is "pyrotag" sequencing, which allows low-cost processing of massive amounts of DNA. The method has been applied to very few samples from deep environments. As a base, this project would examine well-preserved samples from four deep settings chosen for their variety and extensive contextual information, for example, permafrost more than 600 meters below the surface on continents. A community meeting in the second year of the project will help build the global network of experts in deep life to achieve the eventual DCO goals.

A fundamental challenge of the Deep Carbon Observatory (DCO) is to distinguish methane (CH4) produced by degradation of relict organic matter ("fossil" fuel) from that produced by inorganic synthesis or from the activity of microbes ("methanotrophs") in the deep biosphere. This grant supports a project to develop and build a tandem gas-source, electron-impact mass spectrometer with sufficient mass resolving power and sensitivity to make it possible to analyze the rare isotopologues of gas molecules present in hydrocarbon deposits, deep crustal reservoirs, and other settings. The proposed instrument will be the first to combine exceptionally high mass resolving power with a gas source inlet to a mass spectrometer. The full cost of the instrument is $2 million. Proposals submitted to the National Science Foundation (NSF) and Department of Energy (DOE) for $1.15 million have won very favorable reviews, and both agencies have indicated a desire to fund the instrument, with Foundation funding completing the funding gap. The Foundation believes support for the mass spectrometer powerfully exemplifies the effective leveraging of Sloan funds, and a working instrument within 24 months could produce significant published scientific results on the provenance of deep methane in natural environments within three to four years.

When the Foundation initiated support for the Deep Carbon Observatory (DCO), advisors and reviewers emphasized the importance of timely instrument development. The success of the DCO's ten-year plan depends not only on network building, fund-raising, and drilling but on instruments ready to do the range of analyses foreseen. Much effort since the July 1, 2009 launch of the DCO has gone into understanding and addressing instrument needs. The DCO leadership invited ten groups to submit requests and plans for instruments that the international leadership deemed especially important and promising. This resulted in seven highly promising projects totaling $1.7 million. This grant will support six of these seven instrument development projects, oversight of which is to be conducted by the Deep Carbon Observatory leadership at the Carnegie Institution of Washington. The seventh project is funded through a separate Sloan Foundation grant to the University of California at Los Angeles. The instruments to be developed and the developing institutions to be funded under this grant are: Institution Instrument University of Southern California Down-hole logging instrumentation University of New Mexico Volcano gas monitoring Stanford University Synchrotron X-ray spectrometer Institute of High Pressure Physics, Troitsk Russia Diamond-anvil cells (high pressure-temperature devices) Moscow State University Gas chromatograph Institute for Physics of the Globe, Paris Gas-source mass spectrometer The inherent challenges of technical progress as well as required matching funds introduce considerable uncertainty into the process of instrument development, but the Foundation believes these projects position the Deep Carbon Observatory well for timely success in this crucial dimension of its activity.

The Foundation's Deep Carbon Observatory (DCO) science program initiated in 2009 aims to revolutionize understanding of the carbon at great depths in Earth's crust and even below, in the mantle. With Foundation support, the sea floor scientific drillers, now united worldwide in the International Ocean Drilling Program (IODP), propose to meet with the emerging deep carbon community, to explore whether the time is ripe to pursue a project to drill a borehole down to the boundary between the Earth's crust and its mantle and whether such an effort should be associated with the Deep Carbon Observatory. Funds from this grant will support this meeting, hosted by the DCO leadership at the Carnegie Institution of Washington, which will aim to achieve clarity about the risks, costs, and benefits of such a project with an eye towards a well-informed decision by the Deep Carbon Observatory about whether it should form a part of the DCO.