Carbon: Quest Underway to Discover its Quantity, Movements, Origin, and Forms in Deep Earth
- Probing the secrets of volcanoes and diamonds, sources of gas and oil, and the origins of life itself, Deep Carbon Observatory scientists publish landmark volume 3 years into historic 10-year, $500 million global collaboration
- Where is the missing carbon? Confirmed quantities amount to small fraction of what should be present
- Research will add knowledge re. overlooked carbon emissions, energy sources
- Diamonds: sparkling “eyes" offering insight into high pressure, temperature environment and Earth history
- DNA reveals possible ‘zombie microbes’ at extreme depths, enigmatic virus ‘viriosphere’
- Subsurface fractures in ‘Earth's oldest ecosystem’ may be ‘Galapagos of the deep’ and yield clues to origins of life itself
From Earth's surface to hundreds of kilometers deeper than oilmen drill, the Deep Carbon Observatory (DCO) is investigating the surprising quantity of carbon in the deep, dark Earth beyond photosynthesis.
The program is investigating deep carbon's movement in the slow convection of the mantle, the percolating fluids of the crust, and the violent emission from volcanoes. It searches for the ancient origin of the deep carbon, and the formation and transformation of its many forms, ranging from gas and oil to diamonds and deep microbes.
A landmark new book, Carbon in Earth, (Volume 75) is the first major product after three years of work by world-leading scientists collaborating in the DCO -- a $500 million, 10-year international program which aims to reveal the quantity, movements, forms and origins of carbon inside our planet (deepcarbon.net; on Twitter @deepcarb).
A small fraction of Earth's carbon is in its atmosphere, seawater and top crusts. An estimated 90% or more is locked away or in motion deep underground — a hidden dimension of the planet as poorly understood as it is profoundly important to life on the surface.
In their volume, DCO scientists say estimates of carbon bound in the metallic core alone range from 0.25 to 1 percent by weight. If 1 percent proves correct, the core sequesters four times more carbon than all known carbon reservoirs in the rest of the planet—and 50 million times as much as that held in the flora and fauna on Earth’s relatively wafer-thin skin far above.
DCO's multi-disciplinary experts aim to shed light by 2019 on this and other deep Earth secrets, including the mysteries behind volcanoes and diamonds, the sources of gas and oil, and the origins of life itself.
Among many new insights and discoveries reported in the volume:
- A marvel of diversity among microbes -- a Galapagos of the Deep -- whose subsurface biomass comprises a large portion of Earth’s total
- An emerging appreciation of the role deep viruses played in the subterranean laboratory where life is thought to have originated
- The ability to estimate the age and depth at which a diamond formed
- ‘Animal, vegetable, mineral’ is nature's recipe for some types of rock
DCO Executive Director Dr. Robert Hazen, Senior Staff Scientist, Geophysical Laboratory, Carnegie Institution of Washington, co-edited the book with John A. Baross of the Seattle-based University of Washington and Adrian Jones of University College, London. More than 50 experts from nine countries contributed to the volume.
Among specific riddles being addressed by DCO experts:
- How much carbon is stored inside Earth?
- What are the reservoirs of that carbon?
- How does carbon move among reservoirs?
- Where are the most significant carbon fluxes between Earth’s deep interior and the surface?
- How much rising carbon is primordial and how much is recycled from the surface?
- Are there deep abiotic sources of methane and other hydrocarbons?
- What is the nature and extent of deep microbial life?
- Did deep organic chemistry play a role in life’s origins?
Selected examples of DCO’s program objectives:
- Round-the-clock, automated, web-accessible observatories measuring CO2 emissions from 25 of the world’s most active volcanoes
- Better estimates of the quantities and speeds involved in Earth's carbon recycling process, whereby new rock material is upwelled at ocean ridges and denser old crust at subduction zones sinks and is swallowed back into deep Earth, sequestering carbon under high temperatures and pressures
- To reliably distinguish biotic (or fossil) methane from abiotic methane within a couple of years
The new volume and details of the global program are the focus of DCO’s International Science Meeting 3-5 March 2013 at the US National Academy of Sciences, Washington, DC. Prior major meetings have taken place in China, Russia, Germany, France, and the UK.