Thank you for your interest in spreading the word about Science. 
 
 NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address. ||||| Image copyright Juerg Matter Image caption The experiment injected 220 tonnes of carbon dioxide several hundred metres underground 
 
 Scientists think they have found a smart way to constrain carbon dioxide emissions - just turn them to stone. 
 
 The researchers report an experiment in Iceland where they have pumped CO2 and water underground into volcanic rock. 
 
 Reactions with the minerals in the deep basalts convert the carbon dioxide to a stable, immobile chalky solid. 
 
 Even more encouraging, the team writes in Science magazine, is the speed at which this process occurs: on the order of months. 
 
 "Of our 220 tonnes of injected CO2, 95% was converted to limestone in less than two years," said lead author Juerg Matter from Southampton University, UK. 
 
 "It was a huge surprise to all the scientists involved in the project, and we thought, 'Wow! This is really fast'," he recalled on the BBC's Science In Action programme. 
 
 Image copyright Lamont-Doherty Earth Observatory Image caption The reactions in the volcanic rock produced immobile carbonates (white deposits) 
 
 With carbon dioxide concentrations in the atmosphere marching ever upwards and warming the planet, researchers are keen to investigate so called "carbon capture and storage" (CCS) solutions. 
 
 Previous experiments have seen pure CO2 injected into sandstone, or deep, salty aquifers. Chosen sites - which have included disused oil and gas wells - have relied on layers of impermeable capping rocks to hold down the carbon dioxide. But the fear is always that the CO2 could find a way to leak back out into the atmosphere. 
 
 Image copyright Juerg Matter Image caption Cores were drilled to check on the progress of the subterranean reactions 
 
 The Carbfix project on Iceland, on the other hand, seeks to solidify the unwanted carbon in place. 
 
 Working with the Hellisheidi geothermal power plant outside Reykjavik, it combined the waste CO2 with water to make a slightly acidic liquid that was then sent hundreds of metres down into the volcanic basalts that make up so much of the North Atlantic island. 
 
 The low pH water (3.2) worked to dissolve the calcium and magnesium ions in the basalts, which then reacted with the carbon dioxide to make calcium and magnesium carbonates. Cores drilled into the experimental site pulled up rock with the tell-tale white carbonates occupying the pore spaces. 
 
 The researchers also tagged the CO2 with carbon-14, a radioactive form of the element. In this way, they were able to tell if any of the injected CO2 was leaking back to the surface or finding its way out through a distant watercourse. No such escape was detected. 
 
 "This means that we can pump down large amounts of CO2 and store it in a very safe way over a very short period of time," said study co-author Martin Stute from Columbia University's Lamont-Doherty Earth Observatory, US. 
 
 "In the future, we could think of using this for power plants in places where there's a lot of basalt - and there are many such places." 
 
 Dr Matter added: "You can find basalts on every continent and, certainly, you can find them offshore because all the oceanic crust - so below the seafloor - is all basaltic rocks. In terms of the availability of basaltic rocks to take care of CO2 emissions globally - no problem." 
 
 Image copyright Thinkstock Image caption Iceland has abundant basalts, but these rocks are not found everywhere 
 
 Image copyright P.HUEY/SCIENCE/AAAS Image caption Some CCS experiments have pumped pure CO2 into sedimentary rocks (L) where the gas is trapped below an impermeable caprock. In CarbFix (R), the CO2 is dissolved in water and chemical reactions at depth then ensure nothing leaks back to the surface 
 
 There is, however, the issue of cost. Capture of the CO2 at power stations and other industrial complexes is expensive, and without incentives it is currently deemed to be uneconomic. The infrastructure needed to pump the gas to the burial site also has to be considered. 
 
 And in the case of the Carbfix approach, a substantial amount of water is required. Only something like 5% of the mass sent underground is CO2. 
 
 Christopher Rochelle is an expert on CCS at the British Geological Survey and was not involved in the Iceland experiment. 
 
 He said Carbfix underlined the importance of moving beyond modelling and lab studies to real-world demonstrations. Only by doing this can the technology readiness be properly assessed. 
 
 "We need to do more field-scale tests, like this one in Iceland, to better understand the types of processes that are ongoing and how fast they work," he told BBC News. 
 
 "Here, they injected into reactive rocks and the minerals precipitated relatively quickly and are then unable to migrate anywhere. That's great, but the rocks under Iceland are different to those under the North Sea, for example. So the approach that is taken is going to have to vary depending on where you are. We are going to need a portfolio of techniques." 
 
 The Hellisheidi geothermal power station has now moved beyond the experiment reported in Science magazine and is routinely injecting CO2 into the subsurface in larger quantities. The company is also burying hydrogen sulphide - another byproduct from the plant. This benefits the locals who have had to suffer the occasional waft of rotten eggs coming over their properties. 
 
 Image copyright Lamont-Doherty Earth Observatory Image caption The Hellisheidi geothermal power station continues to pump CO2 under Iceland 
 
 Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos ||||| Carbon dioxide is a problem. And everyone knows the best thing to do with problems is bury them deep in the ground and forget they ever existed. 
 
 Practical-minded environmentalists and coal sympathizers alike have long touted carbon capture and underground storage as a low-emissions way to help the world's economy wean itself off fossil fuels. But extracting the troublesome greenhouse gas from power plant emissions is usually way too expensive to be worthwhile. Plus there's the fear that the stuff might leak from its tomb. But a plant in Iceland might have found a solution. By pumping the stuff into volcanic basalt, the CarbFix Project has converted 95 percent of the CO 2 emissions from a geothermal plant into solid carbonate minerals. 
 
 A miracle!? Not quite. But we'll get to that in a second. First you should know a few things about typical, high-investment carbon capture and storage—for starters, that carbon isn't captured (sadly) by tying giant balloons around smoke stacks. "It turns out it is captured chemically rather than physically," says Bill Moomaw, lead author of a 2005 IPCC report on carbon capture and storage. Carbon-scrubbing power plants equip their exhausts with filters with amines that bind carbon dioxide molecules. 
 
 After capturing the CO 2 , plant operators have to release it from the amines by raising the temperature until the CO 2 turns back into a gas. Then they cool it down again—down to like -30, -40 degrees Fahrenheit—so it becomes a liquid that can be pumped into a subterranean cavern. Hopefully that cavern doesn't leak, because the carbon dioxide could need anywhere from hundreds to thousands of years to turn into limestone. 
 
 "And all this takes energy," says Moomaw. For every three coal power plants capable of carbon capture and storage, you have to build a fourth to provide power to those operations. "And even at the efficiencies we have now, you only remove about 25 to 35 percent of the CO 2 ," he says. 
 
 A New Model 
 
 So it makes sense why there are so few carbon capture and storage projects worldwide. The Iceland project is different. For one, it isn't attached to a coal plant. "In 2006 the president of Iceland visited Columbia University and got in touch with a bunch of environmental researchers," says Martin Stute, co-author of a new study published today in Science describing the CarbFix project. "He wanted to try to push Iceland towards not emitting any CO 2 , so he recommended we get in touch with Reykjavik Energy to capture carbon from a large geothermal plant." Even though considered to be clean energy, geothermal plants emit a significant amount of carbon, because the steam used to turn the turbines comes from heat originating deep in the earth. 
 
 In 2012, Stute and the rest of the team began a pair of pilot studies, starting with a proof-of-concept using pure, commercial-grade CO 2 . That went swell, so the team went ahead and started pumping emissions from the power plant, which are a mixture of CO 2 , hydrogen sulfide, and other gases, about 500 meters deep into the basalt substrate—which is the other way this carbon capture scheme is different. Most storage plans involve huge underground reservoirs, like those left over after pumping oil or gas out. 
 
 Once in the basalt the gases mix with water, creating a fizzy liquid like soda. But the pressure is so intense these bubbles don't escape. Basalt is pretty reactive, and also relatively porous. At those pressures and temperatures (about 70˚F), the CO 2 started forming chalky veins in the basalt within two years. Most capture schemes end up losing a lot of carbon to leakage—some up to 75 percent. But using a number of measurements, CarbFix judges that only around 5 percent of the pumped CO 2 was escaping. 
 
 Because they pump the Hellisheidi geothermal plants emissions directly into the ground, the plant's operators do not have to divert a bunch of energy (and money) to the chemical process used to separate carbon. Stute says the CarbFix capture program adds no real extra cost to the plant's operations. "The CO 2 is captured, runs into a pipeline, and on site goes through two pipes into the injection well," he says. 
 
 Beyond Iceland 
 
 Hold your excitement. 
 
 This is not a solution to the world's carbon woes. For one, geothermal plants like the one in Iceland only emit about 5 percent as much CO 2 as coal plants. That means most plants will need a lot of underground real estate to bury their emissions. Also, coal plant emissions are different, and much dirtier. No one is quite sure if they will have the same quick chemical conversion to solid mineral form. 
 
 And finally, geography. Iceland is a volcanic island, sitting atop vast underground plains of basalt. Only few places above water are so blessed, and shipping carbon to them is probably a no-go. "Between the NIMBY problem and regulatory issues, piping CO 2 is a pretty politically dicey proposition," says Moomaw. The Pacific Northwest is the only region in the continental US with substantial basalt, and those hippies are already leagues beyond the rest of the country in terms of clean energy (mostly due to ample hydroelectric power). 
 
 Stute sees a path forward. "Most of the ocean floor is basalt," he points out. "A lot of people live near the coast, and a lot of power plants are near the coast." He says piping the stuff offshore might not be as shaky a proposition as building say, a gigantic Keystone XL for carbon. "And even if there's a leak, the CO 2 would go into the ocean and dissolve immediately." 
 
 Not that he endorses this as a one-stop solution to climate change. "This is not a tool to extend fossil fuel use forever," he says. "We need renewables, reduced emissions, and other solutions." Because if you've been watching the recent episodes of Game of Thrones, you know exactly what happens to problems you try to bury. ||||| CarbFix Project 
 
 Databases 
 
 As a part of the FP7 funded CarbFix project (no. 283148), the CarbFix team has created improved computer accessible databases describing the thermodynamics and kinetics of fluid-rock interaction during carbon-capture and storage efforts. The databases are open source and can be downloaded below. 
 
 Thermodynamic database 
 
 A thermodynamic dataset describing 36 mineral reactions of interest for CO 2 –water–basalt interaction associated with CO 2 mineral sequestration was assessed and generated. Mineral selection for the dataset was based on extensive review of natural analogs of water–basalt interaction at low and elevated CO 2 conditions. Widely used thermodynamic databases did not contain the mineral assemblage needed for successfully simulating the alteration processes observed in nature as important primary and secondary minerals were found to be missing. 
 
 The EQ3/6 V7.2b database was the primary source for aqueous equilibrium constants in the developed dataset but reactions for four missing Al-hydroxy complexes were added. Recently published thermodynamic data were compiled for most of the minerals considered in this study. Mineral solubility constants obtained directly from measurements were compiled to the dataset without modification but SUPCRT92 was used for computing solubility constants when such data was not available. To verify that the presented dataset can capture alterations observed in nature, simulations of CO 2 –water–basalt interaction were carried out at low and elevated CO 2 conditions and compared to observed basalt alteration in Iceland and Greenland. Overall simulated and observed alteration are in close agreement, both at low and elevated CO 2 conditions, suggesting the dataset to be well suited for simulations of e.g. CO 2 –water–basalt interaction associated with CO 2 mineral sequestration in basalts. 
 
 Click the document below to access the thermodynamic database. 
 
 thermodynamic_database.pdf 
 
 Kinetic database 
 
 A general database of the current state of knowledge of the rates of mineral dissolution and precipitation reactions has been created by the CarbFix team over the past three years. The database currently contains more than 110 rock forming minerals, and has been put into general form such that it can be readily applied by the scientific community to assess the potential of fluid-rock interactions during carbon capture and storage efforts. 
 
 This database was created by first collecting and correlating the existing kinetic rate data available in the scientific literature. In cases where adequate fits of these data were already available in the literature, such fits were adopted in this study. In other cases we have sought to provide a quantitative description of these data consistent with what is known about the dissolution and/or precipitation mechanism of the minerals. The resulting and adopted equations have been incorporated into a PHREEQC enabled computer script to all it to be applied directly in conjunction with this geochemical modelling code. Note that PHREEQC is widely available geochemical computer modelling code, originally created at the US Geological Survey and available free to any potential user via the web, 
 
 Click the document below to access the kinetic database. 
 
 CarbFix Report 5 PHREEQC mineral dissolution kinetics database 
 
 Why CarbFix? 
 
 Reducing industrial CO 2 emissions is considered one of the main challenges of this century. By capturing CO 2 from variable sources and injecting it into suitable deep rock formations, the carbon released is returned back where it was extracted instead of freeing it to the atmosphere. This technology might help to mitigate climate change as injecting CO 2 at carefully selected geological sites with large potential storage capacity can be a long lasting and environmentally benign storage solution. 
 
 To address this challenge, the CarbFix project is designed to optimize industrial methods for storing CO 2 in basaltic rocks through a combined program consisting of, field scale injection of CO2 charged waters into basaltic rocks, laboratory based experiments, study of natural analogues and state of the art geochemical modeling. A second and equally important goal of this research project is to generate the human capital and expertise to apply the advances made in this project in the future. 
 
 This research program includes: 
 
 Field scale injection of CO 2 charged waters into basaltic rocks at the Hellisheidi natural laboratory. The Hellisheidi natural laboratory, situated in the Hengill area, SW Iceland, comprises ideal conditions for studying the feasibility of permanent CO 2 storage as minerals in basaltic rocks due to availability of CO 2 and water, the presence of fresh basalts, suitable geological structures, and an extensive infrastructure. Laboratory experiments research program. The emphasis of this experimental program is to quantify basalt dissolution and carbonate precipitation rates stemming from CO 2 injection. Studies of natural CO 2 –rich water reactivity as natural analogues to the behavior of injected CO 2 . A significant number of natural sites have experienced basalt interaction with CO 2 charges waters. Studies of these systems provide insight into the long-term stability of basalt hosted CO 2 storage. Geochemical modeling will be performed to interpret laboratory experiments and field work as well as to predict/optimize the long-term behavior of CO 2 injection sites. 
 
 Details and results of this research program, including regular updates, can be found on this website. 
 
 The CarbFix team 
 
 Four partners have been involved with the project from its inception in 2007: 
 
 Orkuveita Reykjavíkur 
 
 Orkuveita Reykjavíkur (Reykjavik Energy) is a public utility that provides electricity, geothermal water for heating, and cold water for consumption and fire fighting, with services extending to 20 communities, covering 67% of the Icelandic population. 
 
 University of Iceland 
 
 The University of Iceland is a progressive educational and scientific institution, renowned in the global scientific community for its research. It is a state university, situated in the heart of Reykjavík, the capital of Iceland. 
 
 Earth Institute - Columbia University 
 
 With 850 scientists, postdoctoral fellows and students working in and across more than 20 Columbia University research centers, The Earth Institute is helping to advance nine interconnected global issues: climate and society, water, energy, poverty, ecosystems, public health, food and nutrition, hazards and urbanization. 
 
 CNSR 
 
 The Centre National de la Recherche Scientifique (National Center for Scientific Research) is a government-funded research organization, under the administrative authority of France's Ministry of Research. 
 
 Two new partners were added after the project received a substantial grant from the European Union in 2011: 
 
 NanoGeoScience – University of Copenhagen 
 
 The University of Copenhagen is the largest Nordic university and is well respected internationally. NanoGeoScience, a part of the Nano-Science Centre, is an international team of approximately 50 physicists, chemists, geologists, mineralogists, biologists, mathematicians and engineers. 
 
 AMPHOS 21 
 
 AMPHOS 21 Consulting S.L. is a SME that provides scientific and technical consultancy services addressing a range of environmental issues, mainly associated with the management and disposal of hazardous wastes, contaminated groundwater and soils as well as environmental planning and management. 
 
 The CarbFix team 
 
 CarbFix is managed by an appointed management team and the project's scientific steering committee: 
 
 Management Team 
 
 The MT consists of 3 (three) members. Orkuveita Reykjavikur appoints 1 (one), the Chairman of the Management Team, and the SSC elects 2 (two) individuals to be on the MT for a period of 2 (two) years at a time. Upon request of any Participant, the 2 representatives elected by SSC on the Management Team will rotate among the Participants, each for a two-year period. 
 
 Hólmfríður Sigurðardóttir (Chairman) - Head of Environmental Affairs - Reykjavik Energy, Iceland - holmfridur.sigurdardottir (at) or.is 
 
 Juerg M. Matter - Doherty Associate Research Scientist - Lamont-Doherty Earth Observatory, USA - jmatter (at) ldeo.columbia.edu 
 
 Andri Stefánsson - Associated Professor at the Institute of Earth Sciences - University of Iceland - as (at) hi.is 
 
 Project Manager 
 
 The PM is appointed by the Management Team and ist fourth member on the Management Team, but with no voting rights. 
 
 Edda Sif Aradóttir - Project Manager - Reykjavik Energy - edda.sif.aradottir (at) or.is 
 
 Scientific Steering Committee 
 
 The SSC mutually work towards the Goal and Objectives for the Project. The SSC is responsible for (i) overall coordination and fostering collaboration among the individual research projects being performed by the Participants; (ii) monitoring the overall progress of the Project and addressing issues as they arise; (iii) selecting research projects that will be funded through the “General Funds” and (iv) electing 2 members of the Management Team. SSC members are responsible for acquiring all relevant expertise needed beyond the capabilities of the members on the committee. 
 
 The SSC consists of 4 (four) members and a personal substitute member for each member. The representative appointed by University of Iceland on the SSC is automatically the Chairman of the SSC. 
 
 Sigurður Reynir Gíslason (Chairman) - Institute of Earth Sciences, University of Iceland - Research Professor - sigrg (at) raunvis.hi.is 
 
 Wallace S. Broecker - Lamont-Doherty Earth Observatory - broecker (at) ldeo.columbia.edu 
 
 Eric H. Oelkers - Research Director - Chemistry and Earth Science - CNRS UMR 5563 / Universtié Paul Sabatier, France - oelkers (at) lmt.obs-mip.fr 
 
 Einar Gunnlaugsson - Manager of Geothermal Research - Reykjavik Energy, Iceland - einar.gunnlaugsson (at) or.is 
 
 Other members of the CarbFix team 
 
 Eiríkur Hjálmarsson - Reykjavík Energy -eirikur.hjalmarsson (at) or.is 
 
 Fidel Grandia - Amphos 21 - fidel.grandia (at) amphos21.com 
 
 Guðni Axelsson - Head of Physics Department - Íslenskar orkurannsóknir - ga (at) isor.is 
 
 Ingvi Gunnarsson - Geochemist, New Power Projects, Research - Reykjavik Energy -ingvi.gunnarsson (at) or.is 
 
 Jordi Bruno - Amphos21 
 
 Knud Dideriksen - NanoGeoScience - University of Copenhagen -knud (at) nano.ku.dk 
 
 Magnús Þór Arnarson - Chemical Engineer, M.Sc. - Hydropower and Industry - Mannvit Engineering - magnusa (at) mannvit.is 
 
 Martin Stute - Ann Whitney Olin Professor of Environmental Science - Co-chair, Department of Environmental Science - Barnard College, Columbia University - Lamont-Doherty Earth Observatory, Columbia University - martin (at) ldeo.columbia.edu 
 
 Selma Olsen - Reykjavík Energy - selma.olsen (at) or.is 
 
 Susan Stipp - NanoGeoScience - University of Copenhagen - stipp (at) nano.ku.dk 
 
 Trausti Kristinsson - Reykjavík Energy - trausti.kristinsson (at) or.is 
 
 Advisory board 
 
 Liana Benning - University of Leeds 
 
 Bénedicte Ménez - IPGP 
 
 Ph.D. Students 
 
 The following Ph.D. Students are working or have finished projects related to the CarbFix Project: 
 
 Sandra Ósk Snæbjörnsdóttir - Ph.D. student - Institute of Earth Sciences, University of Iceland - Title of Ph.D. Thesis: Field injection experiments and storage capacity estimate. Ph.D. Supervisor: Sigurður Reynir Gíslason. 
 
 Alexandra Murata (undergraduate student) - Columbia University 
 
 Bailey Griswold (undergraduate student) - Columbia University 
 
 Jennifer Hall (graduate student) - Columbia University 
 
 Alexandra Bausch (lab technician) - Columbia University 
 
 Alexander Gysi - Ph.D. student - Institute of Earth Sciences, University of Iceland - apg2 (at) hi.is - Has defended thesis - Title of Ph.D. Thesis: Experimental and numerical modelling of CO2-water-basalt interaction - Ph.D. Supervisor: Andri Stefansson 
 
 Gabrielle J. Stockmann - Ph.D. graduate - Institute of Earth Sciences, University of Iceland - gjs3 (at) hi.is - Defended thesis in May 2012 - Title of Ph.D. Thesis: Experimental determination of the effect of precipitated mineral coatings on the rates of basaltic mineral and glass dissolution rates - Ph.D. Supervisor: Domenik Wolff-Boenisch, Sigurdur Gislason and Eric Oelkers 
 
 Edda S.P. Aradóttir - Ph.D. graduate - Institute of Earth Sciences, University of Iceland - edda.sif.aradottir (at) or.is - Defended thesis in Oct 2011 - Title of Ph.D. Thesis: Reactive Transport models of CO2-water-basalt interaction and applications to CO2-mineral sequestration. Supervisors: Hannes Jónsson, Eric L. Sonnenthal and Grímur Björnsson. 
 
 Helgi Arnar Alfreðsson - Ph.D. student - Institute of Earth Sciences, University of Iceland - haa4 (at) hi.is - Title of Ph.D. Thesis: Characterization of the rocks and fluids, before and after CO2 injection, at the Hellisheidi Iceland site - Ph.D. Supervisor: Sigurdur Gislason, Björn Hardarson, Hjalti Franzson, Domenik Wolff-Boenisch, Andri Stefansson 
 
 Iwona Galeczka - Ph.D. student - Institute of Earth Sciences, University of Iceland - img3 (at) hi.is - Title of Ph.D. Thesis: Experimental studies on the sequestration of CO2 in basaltic rocks - Ph.D. Supervisor: Domenik Wolff-Boenisch, Sigurdur Gislason, Andri Stefansson 
 
 Kiflom Gebrehiwot Mesfin - Ph.D. student - Institute of Earth Sciences, University of Iceland - Title of Ph.D. Thesis: Mineral sequestration of carbon dioxide from geothermal activities in seawater. - Ph.D. Supervisors: Domenik Wolff-Boenisch and Sigurdur Reynir Gislason 
 
 Snorri Guðbrandsso n - Ph.D. student - Institute of Earth Sciences, University of Iceland - snorgud (at) hi.is - Title of Ph.D. Thesis: Dissolution rates of crystalline basalt as a function of temperature, pressure and solution composition - Ph.D. Supervisor: Domenik Wolff-Boenisch, Sigurdur Gislason and Eric Oelkers 
 
 Therese Kaarbo Flaathen - Ph.D. Graduate - Institute of Earth Sciences, University of Iceland - therese (at) hi.is - Defended thesis in September 2009 - Title of Ph.D. Thesis: Natural analogue for CO2 fixation in basalt and the effect of sulphur on the dissolution rate of basalt and precipitation rate of carbonates - Ph.D. Supervisor: Sigurdur Gislason, Eric Oelkers 
 
 Jonas Olsson – Ph.D. student - University of Copenhagen - jolsson (at)hi.is - Title of Ph.D. Thesis (working title): The mobility of heavy metals in natural waters. - Name of thesis supervisor: Susan Louise Svane Stipp and Sigurður Reynir Gíslason. 
 
 Olivier BOS C – Ph.D. student - Université Paul Sabatier, Toulouse - boscolivier (at) hotmail.com - Title of Thesis: Experimental characterization of carbonate precipitation rates and their application to carbon sequestration - Thesis supervisor: Dr. Eric H. Oelkers 
 
 Julien Declercq - Ph.D. - Université Paul Sabatier - declercq (at) get.obs-mip.fr 
 
 M.Sc. Students 
 
 The following M.Sc. students have finished projects related to CarbFix Project: 
 
 Elísabet Vilborg Ragnheiðardóttir - M.Sc. Graduate, REYST - elisabet.vilborg.sigurdardottir (at) reyst.is - Defended thesis in January 2010 - Title of M.Sc. Thesis: Costs, Profitability and Potential Gains of the CarbFix Program 
 
 Mahnaz Rezvani Khalil Abad - M.Sc. Graduate, University of Iceland - mar7 (at) hi.is - Defended thesis in September 2008 - Title of M.Sc. Thesis: Characterization of the Hellisheidi-Threngsli CO2 sequestration target aquifer by tracer testing 
 
 Diana Fernandez de la Reguera – M.Sc. Graduate, Lamont-Doherty Earth Observatory, US - diana (at) ldeo.columbia.edu - Title of Thesis: Monitoring and verification of geologic CO2 storage using tracer techniques - Ph.D. Supervisor: Jurg Matter, Martin Stute 
 
 Luke Brough – M.Sc. Student, University of Waterloo/University of Copenhagen - lgbrough (at) gmail.com - Title: CO2 seqestration in basalt at ambient temperature and pressure - Supervisors: David Blowes, Richard Amos, Susan L. S. Stipp, Knud Dideriksen 
 
 Inger Aaberg – M.Sc. Student, University of Copenhagen - iaaberg (at) nano.ku.dk - Title: Mineral carbonation of CO2 –characterization of olivines during and after reaction using high resolution techniques - Supervisors: Susan L. S. Stipp, Emil Makovicky, Knud Dideriksen 
 
 FAQs 
 
 1. Why mineralogical storage of CO2? 
 
 In geological CO2 storage, CO2 is stored in deep underground formations, such as depleted oil and gas reservoirs and deep saline aquifers. Oil and gas reservoirs have naturally stored CO2 and other gases and fluids for millions of years without significant leakage. However, nothing is absolutely sure. Therefore, mineralogical CO2 storage is aimed at permanently storing CO2 in form of carbonate minerals. By bringing CO2 to its thermodynamic ground state, which is a carbonate mineral, potential health, safety and environmental risks are minimized. 
 
 2. Why basalt and why Iceland? 
 
 Basaltic rocks are one of the most reactive rock types of the Earth’s crust. Basaltic rocks contain reactive minerals and glasses with high potential for CO2 sequestration. More than 90% of Iceland is made of basalt. The process where CO2 from solidifying magma reacts with calcium from the basalt and forms calcite, occurs naturally and the mineral is stable for thousands of years in geothermal systems. Chemical weathering of basalts at the surface of the Earth is another example of carbon fixation in nature. The proposed experiment will aim at accelerating these natural processes. 
 
 3. What happens chemically when the injected CO2 enters the basaltic bedrock? 
 
 CO2 dissolves into the groundwater and the pH of the groundwater decreases as a first consequence of injedting CO2. This low pH groundwater leads to a large number of coupled chemical reactions including the dissolution of basalt which both neutralizes the acidic groundwater and leads to the precipitation of stable carbonate minerals and thus the permanent storage of the injected CO2. 
 
 4. How fast is the CO2 mineralization in the lab vs. field? 
 
 In the lab, McGrail et al. (2006) showed that exposing basalt samples from the Columbia River Basalt (USA) to CO2-saturated water yielded calcium carbonate mineral formation in four to six weeks and extensive mineralization within several months. The CO2 mineralization rate in the field is unknown today. This is the main motivation for the CarbFix project, to conduct the field injection experiment and to monitor the CO2 mineralization rate in situ in the field. 
 
 5. How do we know that the CO2 injected will stay captured and not leak into the atmosphere? 
 
 The injected CO2 will be monitored and the storage safety will be verified by a set of technologies. These monitoring technologies (e.g. CO2 detectors, soil gas analysis, seismic survey, pressure monitoring, geochemical tracers in groundwater etc.) are critical to measure the amount of CO2 stored at a specific sequestration site, to monitor potential leaks, to track the location of the underground CO2 plume, to detect chemical reaction between CO2, groundwater and rocks, and to verify that the CO2 is stored in a permanent way. 
 
 6. What is the status of CO2 mineral storage in the world, is it only happening in Iceland? 
 
 Iceland is the ideal place to develop the technology to store CO2 in the subsurface as stable carbonate minerals for several reasons including: 
 
 1) Iceland is made up of basalt, a rock that contains abundant divalent metal cations, such as Ca (calsium), Fe (iron) and Mg (magnesium), which are the building blocks for making stable carbonate mineral. 
 
 2) Iceland is among the few countries that has the scientific and engineering know-how, due to their long experience in geothermal energy to perform a successful field scale test and develop the technology to export the new technology developed from the CarbFix program. 
 
 Besides the CarbFix project in Iceland, the Big Sky Regional Partnership, one of the seven U.S. Department of Energy partnerships for carbon capture and sequestration, is conducting a CO2 injection pilot test in the Columbia River Basalt in NW of the United States to study the in situ mineralization of CO2 (http://www.bigskyco2.org/). 
 
 7. Where are the good mineralogical CO2 storage sites? 
 
 The mineralization of CO2 requires the availability of divalent cations such as Ca (calsium) , Mg (magnesium), and Fe (iron). Basaltic and peridiotic rocks consist of minerals rich in Ca, Mg and Fe and are therefore ideal for mineralogical storage of CO2. Basalt is the one of the common rock type in Earth’s crust. Over 10% of the continental crust is made up of basalts. Perhaps even more exciting is that most continents are surrounded by massive basalt formations (oceanic crust), just offshore, providing local CO2 storage sites easily accessible for most countries. Basalt formations onshore and offshore together have sufficient storage capacity to contain all human produced CO2 for the foreseeable future. 
 
 The universities have enrolled PhD students to work on science projects in the laboratory as well as in the field, closely linked to the CarbFix project. 
 
 Publications 
 
 The reduction of industrial CO2 emissions is considered one of the main challenges of this century. To address this challenge, the CarbFix project is designed to optimize industrial methods for storing CO2 in basaltic rocks through a combined program consisting of, field scale injection of CO2 charged waters into basaltic rocks, laboratory based experiments, large scale plug-flow experiments, study of natural CO2 waters as natural analogue and state of the art geochemical modelling. A second and equally important goal of this research project is to generate the human capital and expertise to apply the advances made in this project in the future. 
 
 This research program includes: 
 
 1. Field scale injection of CO2 charged waters into basaltic rocks at the Hellisheidi natural laboratory. The Hellisheidi natural laboratory, situated in the Hengill area, SW Iceland, comprises ideal conditions for studying the feasibility of permanent CO2 storage as minerals in basaltic rocks due to availability of CO2 and water, the presence of fresh basalts, suitable geological structures, and an extensive infrastructure. 
 
 2. Laboratory experiments research program. The emphasis of this experimental program is to quantify basalt dissolution and carbonate precipitation rates stemming from during CO2 injection. 
 
 3. Large scale plug flow experiments. The plug flow reactors will be used to fine tune reactive transport models and they might provide an industrial method for fixing CO2. 
 
 4. Studies of natural CO2–rich water reactivity as natural analogue to the behaviour of injected CO2. A significant number of natural sites have experienced basalt interaction with CO2 charges waters. Studies of these systems provide insight into the long-term stability of basalt hosted CO2 storage. 
 
 5. Geochemical modelling. Geochemical modelling will be performed to interpret laboratory experiments and field work as well as to predict/optimize the long-term behaviour of CO2 injection sites. 
 
 Details and results of this research program, including regular updates, can be found on this website. 
 
 International Journals: 
 
 Alfredsson, H.A., Hardarson, B.S., Franzson, H., Gislason, S.R. (2008). CO2 sequestration in basaltic rock at the Hellisheidi site in SW Iceland:Stratigraphy and chemical composition of the rocks at the injection site. Mineralogical Magazine 72, 1-5. 
 
 Alfredsson H. A., Oelkers E. H., Hadrarson B. S., Franzson H., Gunlaugsson E. and Gislason S. R. (2013) The geology and water chemistry of the Hellisheidi, SW-Iceland carbon storage site. Int. J. Greenhouse Gas Control 12, 399–418. 
 
 Alfredsson, H.A., Oelkers, E.H. and Gislason, S.R., (2013). The predicted fate of CO2 injected into basaltic rock. New Zealand Geothermal Workshop 2012 Proceedings 19 - 21 November 2012 Auckland, New Zealand, 5 pp. 
 
 Aradóttir E.S.P., Sigurðardóttir, H. Sigfússon, B. and Gunnlaugsson, E. (2011). CarbFix: a CCS pilot project imitating and accelerating natural CO2 sequestratioon. Greenhouse Gas Sci Technol. 1: 105-118. 
 
 Aradóttir E. S. P., Sonnenthal E. L. and Jónsson H. I. (2012) Development and evaluation of a thermodynamic dataset for phases of interest in CO2 sequestration in basaltic rocks. Chem. Geol. 304–305, 26–38. 
 
 Aradóttir E. S. P., Sonnenthal E. L., Björnsson G. and Jónsson H. (2012) Multidimensional reactive transport modeling of CO2 mineral sequestration in basalts at the Hellisheidi geothermal field, Iceland. Int. J. Greenhouse Gas Control9, 24-40. 
 
 Aradóttir E.S.P et al. (2012) Towards cleaner geothermal energy utilization: capturing and sequestering CO2 and H2S emissions from geothermal power plants. PROCEEDINGS, TOUGH Symposium 2012, Lawrence Berekeley National Laboratory, Berkeley California, September 17-19. 
 
 Aradóttir E.S.P., Sigfússon B, Sonnenthal EL, Björnsson G and Jónsson H. (2013). Dynamics of basaltic glass dissolution – Capturing microscopic eﬀects in continuum scale models. Geochimica et Cosmochimica Acta 121 311–327. 
 
 Aradóttir ESP et al. (2014) Towards Cleaner Geothermal Energy Utilization: Capturing and Sequestering CO2 and H2S Emissions from Geothermal Power Plants, Transport in Porous Media, (In press). DOI 10.1007/s11242-014-0316-5 
 
 Declercq J, Diedrich T, Perrot M, Gislason SR, Oelkers EH (2013). Experimental determination of rhyolitic glass dissolution rates at 40–200 C and 2 < pH < 10.1. Geochimica et Cosmochimica Acta 100. 
 
 Declercq J, Bosc O, Oelkers EH (2013). Do organic ligands affect forsterite dissolution rates? Applied Geochemistry 39 69-77. 
 
 Flaathen, T.K., Oelkers, E.H. and Gislason, S.R. (2008). The effect of aqueous sulphate on basaltic glass dissolution rates. Mineralogical Magazine 72, 39-41. 
 
 Flaathen, T.K., Gislason, S.R. and Oelkers E.H. (2009). Chemical evolution of the Mt. Hekla, Iceland, groundwaters: A natural analogue for CO2 sequestration in basaltic rocks. Applied Geochemistry, 24, 463-474. 
 
 Flaathen, T.K., Gislason, S.R., Oelkers, E.H., (2010). The effect of aqueous sulphate on basaltic glass dissolution rates. Chem. Geol. 277, 345–354. 
 
 Flaathen T. K., Oelkers E. H., Gislason S. R. and Aagaard P. (2011) The effect of dissolved sulphate on calcite precipitation kinetics and consequences for subsurface CO2 storage. Energy Procedia 4, 5037–5043.Gysi, A.P., Stefansson, A., 2011. CO2–water–basalt interaction. Numerical simulation of low temperature CO2 sequestration into basalts. Geochim. Cosmochim. Acta 75, 4728–4751. 
 
 Galeczka I., Wolff-Boenisch D. and Gislason S. R. (2013) Experimental studies of basalt–H2O–CO2 interaction with a high pressure column flow reactor: the mobility of metals. Energy Procedia 37, 5823–5833. 
 
 Galeczka IM, D Wolff-Boenisch, T Jonsson, B Sigfusson, A Stefansson, SR Gislason (2013). A novel high pressure column flow reactor for experimental studies of CO2 mineral storage. Applied Geochemistry 30, 91-104. 
 
 Galeczka I. M., D. Wolff-Boenisch, E. H. Oelkers, S. R. Gislason (2014). An experimental study of basaltic glass–H 2 O-CO 2 interaction at 22 and 50° C: Implications for subsurface storage of CO 2 . Geochimica et Cosmochimica Acta 126, 123-145. 
 
 Galeczka I. M., , E.H. Oelkers, S.R. Gislason (2014). The chemistry and element fluxes of the July 2011 Múlakvísl and Kaldakvísl glacial floods, Iceland. Journal of Volcanology and Geothermal Research 273, 41–57. 
 
 Gislason, S.R., Wolff-Boenisch, D., Stefansson, A., Oelkers, E.H., Gunnlaugsson, E., Sigurdardottir, H., Sigfusson, B., Broecker, W.S., Matter, J.M., Stute, M., Axelsson, G. and Fridriksson, T. (2010). Mineral sequestration of carbon. International Journal of Greenhouse Gas Control, 4, 537-545. 
 
 Gislason SR and Oelkers EH.(2014). Carbon Storage in Basalt. Science 344, 373-374. 
 
 Gislason S.R et al. (2014). Rapid solubility and mineral storage of CO2 in basalt Energy Procedia (in press). 
 
 Gudbrandsson, S., Wolff-Boenisch, D., Gíslason, S.R. and Oelkers, E.H.(2008). Dissolution rates of crystalline basalt at pH 4 and 10 and 25-75°C. Mineralogical Magazine 72, 155-158. 
 
 Gudbrandsson S., Wolff-Boenisch D., Gislason S. R. and Oelkers E. H. (2011) An experimental study of crystalline basalt dissolution from 2 6 pH 6 11 and temperatures from 5 to 75°C. Geochim. Cosmochim. Acta 75, 5496–5509. 
 
 Gudbrandsson S., Wolff-Boenisch D., Gislason S. R. and Oelkers E. H. (2014). Experimental determination of plagioclase dissolution rates as a function of its composition and pH at 22°C. Geochim. Cosmochim. Acta 139 (2014) 154–172 
 
 Gunnarsson I, Aradóttir ES, Sigfússon B, Gunnlaugsson E and Júlíusson BM, (2013), Geothermal Gas Emission From Hellisheidi and Nesjavellir Power Plants, Iceland, GRC Transactions, Vol. 37, 785-789. 
 
 Gysi, A.P. and Stefánsson, A. (2008). Numerical modelling of CO2-water-basalt interaction. Mineralogical Magazine 72, 55-59. 
 
 Gysi, A.P., Stefansson, A., (2012). CO2-water-basalt interaction. Low temperature experiments and implications for CO2 sequestration into basalts. Geochim. Cosmochim. Acta. 81, 129-152. 
 
 Gysi, A.P., Stefansson, A., (2012). Mineralogical aspects of CO2 sequestration during hydrothermal basalt alteration - An experimental study at 75 to 250 °C and elevated pCO2. Chem. Geol. 306-307, 146–159. 
 
 Gysi, A.P., Stefansson, A., (2012). Experiments and geochemical modeling of CO2 sequestration during hydrothermal basalt alteration. Chem. Geol. 306-307, 10–28.Helgi A. Alfredsson, D. W. Boenisch and A. Stefánsson. (2011). CO2 sequestration in basaltic rocks in Iceland: Development of a piston-type downhole sampler for CO2 rich fluids and tracers. Energy Procedia 4, 3510–3517. 
 
 Matter, J.M., Broecker, W.S., Stute, M., Gislason, S.R., Oelkers, E.H., Stefansson, A., Wolff-Boenisch, D., Gunnlaugsson, E., Axelsson, G. and Bjornsson, G. (2009). Permanent Carbon Dioxide Storage into Basalt: The CarbFix Pilot Project, Iceland. Energy Procedia, 1, 3641-3646. 
 
 Matter JM, Broecker, W., Gislason, S. R., Gunnlaugsson, E., Oelkers, E., Stute, M., Sigurdardóttir, H., Stefansson, A., Wolff-Boenisch, D., Axelsson, G., Sigfússon, B. (2011). The CarbFix Pilot Project – Storing Carbon Dioxide in Basalt. Energy Procedia 4, 5579–5585. 
 
 Oelkers E.H., S.R. Gislason, and J. Matter (2008). Mineral Carbonation of CO2, Elements, Vol. 4, 331-335. 
 
 Olsson J, Stipp SLS, Makovicky E, and Gislason SR. (2014) . Metal scavenging by calcium carbonate at the Eyjafjallajökull volcano: A carbon capture and storage analogue. Chemical Geology 384 135–148. 
 
 Ragnheiðardóttir E, Sigurðardóttir H, Kristjánsdóttir H and Harveyd W. (2011). Opportunities and challenges for CarbFix: An evaluation of capacities and costs for the pilot scale mineralization sequestration project at Hellisheidi, Iceland and beyond. International Journal of Greenhouse Gas Control. 5: 1065–1072. 
 
 Rezvani Khalilabad, M., Axelsson, G. and Gislason, S.R. (2008). Aquifer characterization with tracer test technique; permanent CO2 sequestration into basalt, SW Iceland. Mineralogical Magazine 72, 121 125. 
 
 Schultz L.N., Dideriksen K., Lakshtanov L., Hakim S.S., Müter D., Haußer F., Bechgaard K. and Stipp S.L.S. (2014) From nanometer aggregates to micrometer crystals: Insight into the coarsening mechanism of calcite. Cryst. Growth Des. 14, 552–558. 
 
 Snæbjörnsdóttir SÓ, Wiese F, Fridriksson Th, Ármansson H., Einarsson GM, Gislason SR. (2014). CO2 storage potential of basaltic rocks in Iceland and the oceanic ridges. Energy Procedia (in press). 
 
 Stefánsson, A, Arnórsson, S, Gunnarsson, I, Kaasalainen, H and Gunnlaugsson E. (2011). The geochemistry and sequestration of H2S into the geothermal system at Hellisheidi, Iceland. Journal of Volcanology and Geothermal Research 202, 179-188. 
 
 Stockmann, G., Wolff-Boenisch, D., Gíslason, S.R. and Oelkers, E.H. (2008). Dissolution of diopside and basaltic glass: the effect of carbonate coating. Mineralogical Magazine 72, 135-139. 
 
 Stockmann G.J., D. Wolff-Boenisch, S.R. Gislason, E.H. Oelkers. (2011) Do carbonate precipitates affect dissolution kinetics? 1: Basaltic glass, Chemical Geology, 284 306-316. 
 
 Stockmann G.J., Liudmila S. Shirokova, Oleg S. Pokrovsky, Pascale Bénézeth, Nicolas Bovet, Sigurdur R. Gislason, Eric H. Oelkers (2012). Does the presence of heterotrophic bacterium Pseudomonas reactants affect basaltic glass dissolution rates? Chemical Geology 296-297, 1–18. 
 
 Stockmann, G.J., Wolff-Boenisch, D., Gislason, S.R., Oelkers, E.H., (2013). Do carbonate precipitates affect dissolution kinetics? 2: Diopside. Chemical Geology 337–338, 55-66. 
 
 Stockmann GJ, Wolff-Boenisch D, Bovet N et al. (2014). The role of silicate surfaces on calcite precipitation kinetics. Geochim Cosmochim Acta 135 231-250. 
 
 Tobler D.J., Rodriguez Blanco J.D., Dideriksen K., Sand K.K., Bovet N., Benning L.G. and Stipp S.L.S. (2014) The effect of aspartic acid and glycine on amorphous calcium carbonate (ACC) structure, stability and crystallization. Geochemistry of the Earth’s Surface meeting, GES-10. Procedia Earth Planet. Sci. 10, 143 – 148. 
 
 Wolff-Boenisch, D., Wenau, S., Gislason, S, and Oelkers, E. H. (2011) Dissolution of basalts and peridotite in the presence of organic and inorganic ligands, in seawater and under pCO2 pressure at 25°C. Implications for mineral sequestration of carbon dioxide. Geochimica Cosmochima Acta 75, 5510-5525. 
 
 Wolff-Boenisch, D:. (2011). On the buffer capacity of CO2-charged seawater used for carbonation and subsequent mineral sequestration. Energy Procedia, 4, 3738–3745. 
 
 PhD Thesis 
 
 Aradottir, E.S.P. (2011). Reactive transport models of CO2-water-basalt interaction and applications to CO2 mineral sequestration. University of Iceland, Reykjavík, Iceland. ISBN: 978-9935-9053-1-4. 
 
 Flaathen, T.K. (2009). Water-rock interaction during CO2 sequestration in basalt. Oddi, Reykjavik, Iceland, 2009 ISBN: 978-9979-9914-1-0. 
 
 Galeczka I. (2013). Experimental and field studies of basalt-carbon dioxide interaction. University of Iceland, Reykjavík, Iceland. ISBN: 
 
 Gudbrandsson, S. (2013). Experimental weathering rates of alunimum-silicates. University of Iceland, Reykjavík, Iceland. ISBN: 
 
 Gysi, A.P. (2011). CO2-water-basalt Interaction: Reaction Path Experiments and Numerical Modeling. University of Iceland, Reykjavik, Iceland, 188 pp., ISBN 978-9935-9038-1-5. 
 
 Stockmann, G.J. (2012). Experimental study of Basalt carbonatization. Ph.D. thesis, University of Iceland, Reykjavik, Iceland, ISBN 978-9935-9038-4-6, 160 pp. 
 
 MSc Thesis 
 
 Aaberg, I. (2013) Characterization of olivine reacted with supercritical CO2 using surface sensitive techniques - Implications for mineral carbonation. University of Copenhagen. 75 p. 
 
 Rezvani Khalilabad, M. 2008. Characterization of the Hellisheidi-Threngsli CO2 sequestration Target Aquifer by Tracer Testing. Oddi, Reykjavik, Iceland, 2008. ISBN: 978-9979-68-252-3. ISSN: 1670-7427 
 
 Ragnheidardottir, E.V. 2010. Costs, Profitability and Potential Gains of the CarbFix Program. pp 107. 
 
 Bsc Thesis 
 
 Madsen, E.K. (2014) Limestone interaction with supercritical CO2: Investigating the implications on limestone morphology and composition. University of Copenhagen. 35 p. 
 
 Petersen, M. L. (2014) Underground storage of carbon dioxide: Investigating the release of trace elements from limestone. University of Copenhagen. 42 p. 
 
 Kragsberger, R.T. (2014) Reactivity of calcite in contact with water and supercritical CO2. University of Copenhagen. 45 p. 
 
 Weihe, S.H.C. (2014) Geological Carbon Dioxide Sequestration: Investigating mineral dissolution and the release of trace elements from limestone upon interaction with scCO2. University of Copenhagen. 45 p. 
 
 Annual Status Reports 
 
 Annual Status Report 2010 - CarbFix CO2 Fixation into Basalts, Hellisheiði, Iceland. 
 
 Annual Status Report 2009 - CarbFix CO2 Fixation into Basalts, Hellisheiði, Iceland. 
 
 Annual Status Report 2008 - CarbFix CO2 Fixation into Basalts, Hellisheiði, Iceland. 
 
 Links 
 
 The International Carbon Conference 2014 
 
 Original Participating Organizations 
 
 European Participating Organizations 
 
 Other Related Sites 
 
 Limited Access 
 
 Logo 
 
 The CarbFix logo is available in three different formats (zip). 
 
 Description of the logo 
 
 Carbon capture and storage (CCS) has become a major issue in the wake of global warming and discussions on effective actions that have to be implemented to reduce the impact of industrial activities on the climate. There are different CCS approaches, however, and a principal aspect of my design was to visualize and transmit the solidness of the CarbFix project in the sense of precipitating solid CO2 as carbonate underground, quite the contrary to the commonly encountered trapping of gaseous CO2 in depleted oil/gas reservoirs. The fundamental difference lies in the physical state of the sequestered CO2 with all implications as to long-term safety and reliability of these different CCS techniques. 
 
 Thus, the notion of solidity is a crucial feature distinguishing this project from other CCS plans and in order to visualize this key point a rectangle was placed in the centre of the logo. A filled rectangle conveys best this impression of hardness/strength of a solid phase quite in contrast to a gas. This element points evidently downwards and can be interpreted as representing the wells and the CO2-supersaturated fluid phase that is pumped underground. The subsequent carbon mineralization process is also insinuated by stark black letters. 
 
 In order for the logo not to appear too static, however, I added a ring to the design. This ring has two functions: It depicts the surface that has to be intersected/drilled to get down to the repository and thus puts the tilted bar into context by giving it an orientation. At the same time the ring as well as the change in its width conveys movement to the logo. This dynamics is another essential feature of the CarbFix project as it includes not only a cooperation between industry and academia but between different countries and this cooperation entails a continuous flux of know-how and experimental results in order to find the best possible solution to this challenging project. As to the chosen colors, the green color is very typical of Icelandic moss and grey/black are ubiquitous colors in the volcanic countryside. Both colors are therefore intimately related to the storage environment of this pilot study, i.e., Icelandic basaltic rocks. 
 
 Designed by Marijo Murillo Graphic Designer (marijomurillo@internet.is) ||||| Radical new technique promises a cheaper and more secure method of burying CO2 emissions underground instead of storing it as a gas 
 
 Carbon dioxide has been pumped underground and turned rapidly into stone, demonstrating a radical new way to tackle climate change. 
 
 The unique project promises a cheaper and more secure way of burying CO2 from fossil fuel burning underground, where it cannot warm the planet. Such carbon capture and storage (CCS) is thought to be essential to halting global warming, but existing projects store the CO2 as a gas and concerns about costs and potential leakage have halted some plans. 
 
 The new research pumped CO2 into the volcanic rock under Iceland and sped up a natural process where the basalts react with the gas to form carbonate minerals, which make up limestone. The researchers were amazed by how fast all the gas turned into a solid – just two years, compared to the hundreds or thousands of years that had been predicted. 
 
 “We need to deal with rising carbon emissions and this is the ultimate permanent storage – turn them back to stone,” said Juerg Matter, at the University of Southampton in the UK, who led the research published on Thursday in the journal Science. 
 
 Matter said the only thing holding back CCS was the lack of action from politicians, such as putting a price on carbon emissions: “The engineering and technology of CCS is ready to be deployed. So why do we not see hundreds of these projects? There is no incentive to do it.” 
 
 The Iceland project has already been increased in scale to bury 10,000 tonnes of CO2 a year and the basalt rocks used are common around the world, forming the floor of all the oceans and parts of the land too. “In the future, we could think of using this for power plants in places where there’s a lot of basalt and there are many such places,” said Martin Stute, at Columbia University in the US and part of the research team. 
 
 Testing has taken place in the Columbia River Basalts, extensive deposits in Washington and Oregon in the US. India, which has many polluting coal power plants, has huge basalt deposits in the Deccan Traps. 
 
 One potential challenge for the new technique is that it requires large amounts of water: 25 tonnes for each tonne of CO2 buried. But Matter said seawater could be used, which would be in plentiful supply at coastal sites. Another is that subterranean microbes might break down carbonate to methane, a powerful greenhouse gas, but this was not seen in the Iceland research. 
 
 The research, called the Carbfix project, took place at Iceland’s Hellisheidi power plant, the world’s largest geothermal facility. The plant pumps up volcanically heated water to run electricity-generating turbines but this also brings up volcanic gases, including carbon dioxide and nasty-smelling hydrogen sulphide. 
 
 The researchers re-injected 230 tonnes of the gas, which was dissolved in water to prevent it escaping, down into the basalt to a depth of 400-500m. They used tracer chemicals to show that over 95% of CO2 was turned into stone within two years, “amazingly fast” according to Matter. Edda Aradottir, who heads the project for Reykjavik Energy, said: “It was a very welcome surprise.” 
 
 Facebook Twitter Pinterest Members of the CarbFix science team handling rock core recovered during drilling at the CO2 injection site. Photograph: Juerg Matter/Science 
 
 The Iceland project has now begun scaling up to bury 10,000 tonnes of CO2 a year, plus the hydrogen sulphide which also turns into minerals. The Columbia University group are also investigating another rock type, found in Oman, which may be able to turn CO2 into rock even better than basalt. 
 
 In conventional CCS, the CO2 is stored as a gas in sedimentary rocks such as exhausted oil fields under the North Sea. Unlike basalt, these rocks lack the minerals needed to convert CO2 into stone. Such sedimentary reservoirs could potentially leak and therefore have to be monitored, which adds to costs. 
 
 They have also raised concerns from the public and projects on land in the Netherlands and Germany have been halted as a result. “In Europe you can forget about onshore CCS,” said Matter. 
 
 Conventional CCS also requires the CO2 to be separated from the mix of gases emitted by power stations and industrial plants, which is expensive. But the basalt-based CCS does not require this. However, Matter said there would still be a role for conventional CCS in places where power plants are close to good reservoirs. 
 
 Stuart Haszeldine, professor of CCS at the UK’s University of Edinburgh and not involved in the new research said it was promising: “This is terrific. It may well provide a low-cost and very secure remedy for parts of the world where the suitable rocks exist. [But] this needs to be used as well as all the existing propositions, because the problem to be solved of thousands of million tonnes of CO2 emissions per year in the world is immense and no single remedy is anywhere near big enough or fast enough.” 
 
 The UN’s Intergovernmental Panel on Climate Change has concluded that CCS is hugely important to tackling climate change in the most cost-effective way. Without CCS, the costs of halting global warming would double, the IPCC said, an assessment with which the UK government’s advisers, the Committee on Climate Change, agrees. 
 
 However, the UK government cancelled a pioneering £1bn CCS competition in November. Globally, CCS has not developed as quickly as hoped, although some companies are using CO2 injection to drive more oil and gas from older fields. Haszeldine said there have been over 100 injections of CO2 gas in different countries worldwide since 1972, none of which are known to have leaked. 
 
 Other innovative approaches to CCS are being explored, including an ExxonMobil-backed project using fuel cells to make capturing CO2 cheaper and one from Ford which uses CO2 to make foam for use in their vehicles. Groups are also working on chemical advances to capture CO2 more easily.
– Here's an idea for dealing with carbon dioxide: Turn it into stone. Scientists in Iceland say they have managed the feat at the world's largest geothermal power plant, an accomplishment the Guardian says could have big implications for climate change. As they explain in Science, researchers with the CarbFix Project figured out how to capture CO2, then pump it into porous volcanic rocks deep in the Earth. There, the gas combined with minerals in the basaltic rocks and turned into limestone. Scientists actually sped up that natural process and were amazed at the results: 95% of the CO2 had turned to stone within two years, reports Wired. When this process occurs naturally, it can take hundreds of thousands of years. "It was a huge surprise to all the scientists involved in the project," lead author Juerg Matter tells the BBC. By burying the emissions so deeply into such a stable form, the carbon dioxide is trapped in such a way that it cannot warm the planet, say the researchers. "In the future, we could think of using this for power plants in places where there’s a lot of basalt and there are many such places," says team member Martin Stute at Columbia University. Testing is already under way in the Columbia River Basalts in the Pacific Northwest, while India, home to many dirty coal plants, also boasts enormous basalt deposits in the Deccan Traps. Researchers are also hoping to find an even better reaction in a rock type found in Oman. The idea of burying CO2 under some kind of carbon capture and storage (CCS) method has been experimented with successfully for decades, but one major concern has revolved around the gas leaking back out. The Iceland method seems to solve that. (See what one company wants to turn carbon pellets into.)