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2012 GCEP Progress Report: Reactivity of CO2 in the Subsurface

Investigators Kate Maher, Assistant Professor, Department of Geological & Environmental Sciences; Dennis K. Bird, Professor, Department of Geological & Environmental Sciences; Gordon E. Brown, Jr., Professor, Department of Geological & Environmental Sciences; Robert J. Rosenbauer, Research Scientist, U.S. Geological Survey, Menlo Park, CA; Yousif Kharaka, Research Scientist, U.S. Geological Survey; Natalie Johnson, Ph.D. Student, Department of Chemical Engineering; Pablo García Del Real, Ph.D. Student, Department of Geological & Environmental Sciences; Seung-Hee Kang, Ph.D. Student, Department of Geological & Environmental Sciences; Joseph Nelson, Ph.D. Student, Geological and Environmental Sciences; Dana Thomas, M.S. Student, Geological and Environmental Sciences.

Abstract

The goal of our research is to interrogate, and ultimately engineer, the key chemical reactions that occur as a result of the injection of CO2 into both ultramafic/basaltic rocks and sedimentary rocks, including saline aquifers and petroleum reservoirs. Our work focuses on two areas: (1) enhancing the conversion of CO2 to carbonate minerals (mineral carbonation), and (2) mineral-fluid-organic reactions that create or destroy porosity and may catalyze the in situ reduction of CO2 to organic compounds. The ability to predict and manipulate reservoir reactivity and reaction products during emplacement of CO2 is a major goal of our research tasks. We have developed an experimental process for studying mineral-fluid reactions at temperatures and pressures relevant to CO2 storage that includes characterization using spectroscopic and x-ray scattering methods (XPS, XRD) as well as nm-scale imaging (STXM, SEM) and the use of isotopic tracers coupled with SIMS (Secondary Ion Mass Spectrometry) to track chemical and physical processes occurring in the 100 to 1000 nanometer thick interface between the fluid and the unreacted crystal. Results from carbonation experiments using forsterite (Mg2SiO4) include the following: (1) reaction rates are enhanced in the presence of supercritical CO2 relative to pure water at the same temperature and pH, (2) the olivine dissolution rate declines as the experiments approach equilibrium with amorphous silica (SiO2(am)), likely due to formation of a Si-rich layer, and (3) the Si-rich coating on forsterite is a leached layer and not a re-precipitate, based on measurement of a 29Si label using SIMS (secondary ion mass spectrometry). Knowledge of the mechanism of apparent silica passivation enables us to engineer an activator that will transport silica away from the mineral surface such that the maximum olivine dissolution rate observed early in our experiments can be maintained. This experimental approach will be used to study other key reactions including: serpentine and basalt carbonation, and clay (smectite-illite) transformations.

Ultimately, the chemical reactions we are investigating will occur within complex geologic settings. Thus, we are examining natural analogues for mineral carbonation in both ultramafic rock (Red Mountain, California) and basalt (western Iceland) and are using literature data sources to assess the mineralogical and redox transformations in sedimentary rocks exposed to CO2. In both ultramafic and basaltic rocks, we find

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evidence for formation of large-scale veins suggesting that coupled mechanical and chemical processes facilitated the conversion of rock to carbonate minerals. The development of coupled thermodynamic and mechanical models, along with appropriate physical and geochronologic constraints is underway. Our preliminary analysis of literature data from saline aquifers suggests that CO2 injection may result in oxidation of the system if the metastable equilibrium between CO2 and organic acids is reversed (or CO2 reduction is catalyzed by natural surfaces). If this is indeed the case, then the Fe(II)-bearing minerals that commonly form cements and shale caprock may be destabilized, resulting in porosity changes and potentially enhanced mineral carbonation.

Introduction Large volumes of carbon dioxide (CO2) will likely be injected into the subsurface as:

(1) a strategy for reducing the release of CO2 to the atmosphere from fossil fuel burning, (2) a potential working fluid for enhanced geothermal systems, and (3) a continuing strategy for enhanced oil and gas recovery. Our objective is to determine the consequences of the reactivity of CO2-bearing aqueous fluids in two key types of geologic reservoirs: crystalline ultramafic and mafic rocks associated with enhanced geothermal systems and sedimentary formations associated with hypersaline aquifers (Benson and Cole, 2008; Bickle, 2009; Tester, 2006). As the CO2 and associated by-products interact with the subsurface minerals and dissolve into local fluids, the ensuing chemical reactions will transform the subsurface environment. Some of these transformations will occur under conditions where thermodynamic variables, such as ion activities and equations of state are incompletely defined (e.g., in hypersaline solutions), necessitating the close coupling of experimental, theoretical, and observational approaches (Lu et al., 2009; Lu et al., 2012a; Zhang et al., 2009).

To address these issues, we are combining batch experimental studies with field studies of CO2-fluid-solid interactions to quantify reaction kinetics and the spatial and temporal distribution of reaction products, and to identify potential processes that could be used to enhance key reactions. Our findings are interpreted using an integrated analysis that includes traditional thermodynamic and kinetic modeling of experimental results, mineralogical analysis and surface chemistry of experimental reaction products, isotopic tracer studies, reactive transport modeling, and geological experience and observations.

Background The number of research groups involved in research on the processes and application

of mineral carbonation is growing rapidly, and includes a large number of domestic and international research groups.1 In addition to studies of ex situ (e.g., Gerdemann et al., 2007; Hansen et al., 2005; Krevor and Lackner, 2011; Larachi et al., 2010; Lee et al.,

                                                                                                               1 Domestic research groups with large programs on mineral carbonation include UC Berkeley/LBNL (Lawrence Berkeley National Lab), PNNL (Pacific Northwest National Lab), Albany Research Center, Yale University, Columbia University and MIT. International research on mineral carbonation include groups in Canada (several), Finland (Helsinki University), France (IPGP, Paris 05; CNRS), Iceland (University of Iceland), Italy, the Netherlands (several), Switzerland (ETH) and the United Kingdom (several).

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2011; McKelvy et al., 2004; Park and Fan, 2004; Pronost et al., 2012; Renforth et al., 2011; Wang and Maroto-Valer, 2011) and in situ mineral carbonation (e.g., Boschi et al., 2009; Daval et al., 2010; Daval et al., 2011; Gudbrandsson et al., 2011; Hanchen et al., 2008; Kelemen and Matter, 2008; Kelemen et al., 2011; King et al., 2010; Kwak et al., 2010; Kwon et al., 2011; Loring et al., 2011; Mani et al., 2008; Mitchell et al., 2010; Oelkers et al., 2008; Olsson et al., 2012; Saldi et al., 2012; Schaef et al., 2010; Shirokova et al., 2012), recent studies have proposed mineral carbonation as part of a pre-combustion CO2 capture process (Larachi et al., 2012) and as a geoengineering strategy that would potentially reduce ocean acidification and remove atmospheric CO2 by distributing fine olivine powder across large regions of the continents (Kohler et al., 2010; Schuiling and de Boer, 2010). However, the main emphasis remains on in situ mineral carbonation, with a number of small (0.1 kt to 1 kt CO2 injected) pilot studies completed or underway (Assayag et al., 2009; Gislason et al., 2010) (see also http://csi.pnnl.gov/). Despite the large number of careful experimental studies, identification and quantification of the underlying controls on the rates and pathways of mineral carbonation remain a critical challenge. For example, a recent study proposed that magnesite (MgCO3) reaction kinetics were the limiting step in mineral carbonation (Saldi et al., 2012). However, our experiments show that the overall rate of MgCO3 precipitation can equal to the rate of olivine dissolution, suggesting that when the overall surface area available for precipitation is accounted for, olivine dissolution can still be rate-limiting. A recent paper also suggested that silicate mineral dissolution is universally characterized by the formation of an amorphous silica precipitate at the crystal surface that is permeable to fluids (Hellmann et al., 2012). Our experiments that incorporated an isotopic tracer (29Si) into olivine and used high-resolution depth profiling of the 29Si distribution with a Sensitive High Resolution Ion MicroProbe (SHRIMP) to characterize reacted olivine do not support this interpretation, and suggest that other silicates should be evaluated in order to test the applicability of this proposed “universal” model. Direct carbonation of olivine in the presence of wet supercritical CO2 (scCO2) has recently been observed using in situ infrared spectroscopy (Loring et al., 2011), a finding that may have implications for other minerals and is also not well described by current models for mineral carbonation. Finally, for in situ carbonation to be successful at converting meaningful quantities of CO2 to stable mineral forms, continual creation of porosity and mineral surface area via fracturing or other means (e.g., bulk dissolution followed by reprecipitation of nanoparticles) is required. Identifying low-cost methods for successfully fracturing ultramafic and basaltic rocks remains a key area of research, and the pervasive fracturing observed in natural analogues may provide important clues.

The geochemical alteration and attendant hydrologic effects during CO2 injection into saline aquifers is receiving more attention as data from pilot injections becomes available and raises awareness of critical knowledge gaps (Kharaka et al., 2009; Lu et al., 2012b, Xu et al., 2010). In addition, a number of recently published studies have highlighted the potential influence of geochemical reactions on the long-term integrity of the caprock (Shao et al., 2010, 2011; Shukla et al., 2010; Wollenweber et al., 2010), the potential expansion and trapping of CO2 by clay minerals (Ilton et al., 2012; Schaef et al., 2012), de-wetting of silica surfaces in the presence of scCO2 (Kim et al., 2012) and ultimately the long-term trapping of sequestered CO2 (Liu et al., 2011). Collectively, these studies suggest that improved knowledge of chemical reactions that occur in systems composed

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of varying mixtures of CO2, water, brine, and organic compounds is required before the mineralogical and structural evolution of subsurface environments exposed to CO2 injection can be predicted. Other recent studies have also considered the co-injection of CO2 and H2S or SO2, as well as the effect of CO2 injection into reservoir brines already containing H2S (Crandell et al., 2010; Ghaderi et al., 2011; Zhang et al., 2011a). The modeling studies of Zhang et al. (2011a) suggest that co-injection may lower the solubility and mineral trapping of CO2 due to dissolution of H2S into formation water and the precipitation of pyrite, while previous studies of H2S and SO2 co-injection suggest increased potential for siderite (FeCO3) precipitation due to enhanced Fe reduction (Murphy et al., 2010; Palandri et al., 2005). Studies of the effect of co-injection (of H2S, SOx, or NOx) on redox process in saline aquifers are still relatively few, and to our knowledge no studies to date have addressed the role of organic acids on mineral transformations, although basinal brines can contain up to 5,000 to 10,000 ppm acetate and 100 to 2,500 ppm malonate, along with many other mono- and dicarboxylic acids at ppm levels (Kharaka and Hanor, 2007). Our initial experimental and modeling work (detailed in the following sections) suggests that organic acids can have a substantial and variable impact on the mechanisms and rates of mineral dissolution and precipitation. We have also identified the coupled chemical and hydrologic evolution of caprock and reservoir materials as important areas for future investigation.

Results Our research to date has focused on (1) experimental and field studies of the reaction

of CO2 with silicates rich in Mg and/or Ca, and (2) mineral-fluid reactions subsequent to the dissolution of CO2 into hypersaline brines and (3) theoretical evaluations of the potential to reverse the metastable equilibrium between CO2 and organic acids. Mineral Carbonation

We have carried out a series of batch experiments examining the carbonation kinetics of forsteritic olivine (Mg2SiO4) – a key mineral in ultramafic rocks such as peridotites and some basalts – and serpentine (Mg3Si2O5(OH)4), variety antigorite. To control both the temperature and pressure during the course of the experiment, the reactions occur inside a flexible gold cell fitted with a valve (to allow fluid sampling during the reaction), and placed inside a stainless steel vessel, which is pressurized using distilled water (Figure 1). All experiments have used well-characterized mineral powder at a ratio of 1:20 by mass, and 3% NaCl solution. Temperature is 60oC and pressure is set by the addition of CO2 to 100 bar resulting in 10-15 mL of supercritical CO2 in the reaction vessel. Various amendments, including isotopes, organic acids and other organic compounds have been added to the experiments. Examples of results and characterization of experimental products are shown in Figure 1.

Our experimental work has demonstrated that organic acids, such as those commonly found in natural waters and deep saline aquifers, are capable of both enhancing and potentially inhibiting dissolution and precipitation reactions. The olivine carbonation experiments suggest that while some organic acids enhance mineral-fluid reaction rates in the presence of CO2 (Figure 1B), there is a threshold of organic acid concentrations (e.g., > ca. 0.1 g/L for salicylic acid) and/or pH (< ~ pH 5) where mineral dissolution rates may actually be suppressed due to interactions between the organics and the mineral surface.

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This finding is consistent with our earlier ATR-FTIR spectroscopic studies of the interaction of carboxylic acids and natural organic matter (e.g., humic acid) with Al-(oxyhydr)oxide particle surfaces (e.g., Yoon et al., 2004a,b; Johnson et al., 2004a,b; Johnson et al., 2005a,b; Yoon et al., 2005), which found that organic acids, such as oxalic acid, that bond to mineral surfaces in an inner-sphere bidentate fashion enhance dissolution, whereas those, such as maleate or humic acid, that form outer-sphere surface complexes inhibit dissolution. However, although the addition of organic acids enhanced both dissolution rates and carbonation rates, the formation of a Si-rich layer still inhibited the dissolution in early stages. In order to find a solution to this problem, we are conducting a series of new experiments with only scCO2 and water (± isotopic tracers). Natural analogues for mineral carbonation: peridotite carbonation

Natural analogues for subsurface carbonation of ultramafic rocks provide valuable insights into the processes that facilitate CO2 storage as carbonate minerals. The characterization of these natural analogues permits the evaluation of geologic environments where CO2 has been effectively transformed to mineral phases. These natural examples of carbonation place fundamental constraints on the boundary conditions in experimental and theoretical studies, and ultimately the implementation of mineral carbonation at large scales. In our effort to couple experimental and field-based research, we continue to focus on the characterization of a striking example of magnesite (MgCO3) mineralization in a peridotite body within the Del Puerto Ophiolite located in of the Diablo Mountain Range, California. Our field site —the Red Mountain Magnesite Mining District—contains large veins (up 40 m in thickness) deposits of cryptocrystalline

Figure 1: (A) Diagram of experimental autoclave used in experiments (B) example results for olivine dissolution in the presence of scCO2, water and salicylic acid; (C) example of secondary siderite (FeCO3) formation during serpentine carbonation and (D) magnesite (MgCO3) formation on serpentine grain.

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magnesite, the carbonate mineral with most potential for CO2 mineral storage (e.g., Oelkers, 2008). We have previously reported field observations, mineral assemblages, magnesite-peridotite structural relationships, stable isotope geochemistry, role of silica (SiO2), and hypotheses on the genesis of the Red Mountain magnesite veins and nodules (Figure 2). A brief summary of these studies is presented in the caption to Figure 2. We are preparing this first phase of our field-based research for publication (García del Real et al. in prep).

We have also investigated the generation of geomechanical work performed by CO2-bearing fluids on host rocks. Our results have shown that solutions enriched with as little as xCO2=0.1 have the ability to produce significant permeability and to rapidly mobilize mineralizing solutions (Maher et al., 2011). This second phase of our research, based on the theoretical behavior of fluids from their respective equations of state, has implications for the generation of fluid pressures capable of rupturing impermeable lithologies. However, to fully evaluate our geomechanical model requires constraints on both the temperature and the timing of the carbonate mineralization. Our current research is thus focused on determining the timing, and hence tectonic setting, of the magnesite mineralization. We are developing approaches for U-Pb geochronology of magnesite and secondary silica materials in order to place the mineralization event in a specific geologic environment. This will complement and validate our models for the genesis of the mineralizing solutions, the source of CO2 and the governing temperature-pressure

Figure 2: Cross section perpendicular to the general strike of the main magnesite veins (white bodies) hosted in variably serpentinized peridotite (gray). Bottom left image: Convoluted relationship between highly sheared serpentinized peridotite (dark) and magnesite (white). Bottom right image: Tectonic contact between one of the largest magnesite veins (white) and peridotite (dark). More than 20 homogenous magnesite veins of variable thickness (up to 40 m) and >100s of m in length are hosted in the variably serpentinized peridotite. The carbonate mineralization occurs primarily as cryptocrystalline magnesite veins with sharp tectonic or sheared/brecciated contacts with the host peridotite rock that lack metasomatic reaction zones. Opaline silica occurs as relatively small late-stage veins paragenetically distinct from the magnesite mineralization and the peridotite host rock.

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conditions of peridotite dissolution and subsequent magnesite precipitation. Our model of the geomechanical work potentially available from CO2-rich fluids could then be applied to a specific geologic setting. Further, recent isotopic (highly depleted δDSERPENTINE ratios, −100‰) and structural data suggest that the last serpentinization event at Red Mountain occurred at shallow crustal levels under a strong flux of meteoric water. Because the magnesite veins intrude serpentinized rocks, we consider the mineralization to have occurred at shallow crustal conditions and low temperatures, consistent with oxygen isotope thermometry in magnesite.

CO2-rich springs in Iceland as a natural analogue to CO2 sequestration in basalt

Recent experimental studies have explored the carbonation potential of different

basalts from around the world and have found vastly different rates and styles of mineral carbonation that cannot be explained purely by compositional differences (Schaef et al., 2010), although the release of Fe appears to be an important factor. A pilot study is currently planned in Iceland, where CO2-rich geothermal waters will be injected into basalt formations (Gislason et al., 2010, see http://www.or.is). The fluid-rock interactions between natural CO2-rich fluids and basaltic rocks in Iceland serve as natural analogues to the possible outcomes of injecting aqueous CO2 into mafic rock reservoirs in order to sequester CO2 by mineral carbonation. To investigate the mineralization of CO2-rich fluids in basalts and the potential release of trace metals (arsenic and other trace metals), we are studying the mineralogy, petrology and fluid chemistry of CO2-rich springs in Iceland.

Figure 3: Sample locations (ÖL = Ölkelda, KH = Klausturhólar and HE = Hæđarendi) in relation to active volcanic zones and geothermal systems. Adapted from Pope et al. 2009 (left). Backscatter electron image of a filled basalt vesicle from well HE-07. Alteration minerals line and fill the vesicle in a matrix of albitic plagioclase, chlorite and pyrite (right).  

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We have obtained from the Iceland GeoSurey (ÍSOR) drill cuttings from four wells in three areas of Iceland: Ölkelda (ÖL), Hæđarendi (HE) and Klausturhólar (KH) (Figure 3). The wells reach to 2500 meters deep and 190°C, with CO2 concentrations ranging from 200 to 2000 ppm and pH ~6 to 9. ÖL-05 and ÖL-10 sample Upper Tertiary alkaline basalts and are located in the Ölkelda region on the Snæfellsnes Peninsula in western Iceland. KH-11 and HE-07 are comprised of younger tholeiitic basalts no older than 3.3 Ma. We are currently assessing the mineral paragenesis that occurs when CO2-rich fluids interact with basalts and hydrothermally altered basalts, with particular emphasis on identifying processes and reactions that lead to carbonate precipitation and will collect complementary fluid samples this summer. Results from scanning electron microscopy (SEM) indicate that albitic plagioclase dominates the remnant primary assemblage. Secondary minerals vary by sample and with depth and include epidote [Ca2(Al2Fe3+)(Si2O7)(SiO4)O(OH)], quartz [SiO2], pyrite [FeS2], carbonates [CaCO3], amorphous silica [SiO2], chlorite [(Fe,Mg)5Al3Si3O10(OH)8] and celadonite [K2(Fe,Al)2(Mg,Fe)2Si8O20(OH)4]. The presence of epidote and quartz strongly suggests hydrothermal alteration in the Ölkelda drill cuttings, whereas the Klausturhólar and Hæđarendi samples lack this evidence of prior alteration. Styles of CO2 mineralization also differ between locations, with diffuse carbonation observed at Ölkelda and discreet large scale veins observed in the Klausturhólar core. We are currently working to identify the underlying causes for the difference in carbonate mineralization between sites. Future work

Mineral carbonation: We are preparing the first sequence of experimental studies on

olivine carbonation that focus on the formation and effect of the Si-rich layer for publication, and running additional experiments to verify the reproducibility of our experimental results prior to submitting these manuscripts. Beyond preparing these publications, our future focus in this area will be on developing approaches for alleviating the effect of the Si-rich layer and thus accelerating the approach to magnesite precipitation. To build on the set of experimental procedures that we have developed, we are undertaking several other experimental studies: (1) serpentine carbonation, (2) evaluation of the dissolution kinetics of feldspar in the presence of scCO2, (3) transformations of clay minerals (smectite/montmorillonite), and (4) experiments involving potential cementing agents that are activated at low pH, and (5) dissolution of Fe(II)-silicates to form carbonate minerals.

Natural analogues studies of Red Mountain peridotite and Iceland basalts: The first publication describing the genesis of magnesite and insights for the feasibility of mineral carbonation from Red Mountain is nearing completion (Garcia Del Real et al., in preparation). Future work will constrain the boundary conditions for the timing and temperature of magnesite mineralization using U-Pb geochronology and both oxygen isotope signatures of serpentinized materials and isotope thermometry of the carbonates. We have also initiated active collaboration with the Qatar Carbonates and Carbon Storage Research Centre and the Carbonate Research Group both at Imperial College London, UK who will conduct clumped isotope analyses (i.e. 47ΔCO2) of Red Mountain magnesite

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to provide direct information on the precipitation temperature that is independent of the fluid source, which is advantageous in substantiating our current models.

We will assess how the alteration history of the basalts impacts mineral carbonation and release of trace metals by performing quantitative chemical analyses of minerals and fluid samples. By identifying what mineral phases in the altered basalts host arsenic and other elements of environmental concern, we can also use mineral stability predictions to assess the potential of such trace metals such as As and Pb to enter the groundwater during CO2 sequestration. Fieldwork this coming summer will involve obtaining additional samples and drill cuttings, mapping the lithology surrounding the ÖL, KH and HE wells and collecting water and gas samples from the springs at the wells.

Model development and integration: Much of our experimental and field characterization work to date has focused on identifying the key processes that control the reactions of interest. Although, we have learned that in some key areas (particularly geochemical reactions relevant to saline aquifers), our focus is shifting towards integrating our data into various types of models that can allow us to pull together multiple constraints to describe the evolution of both the experimental and field systems. The focus in the coming year will shift towards building and evaluating models that can be used to predict aspects of subsurface evolution in systems where CO2 is emplaced.

Abstracts and Publications:

Johnson, N. C., Thomas B., Maher, K., Bird, D. K., Rosenbauer, R. Brown, G. E. Jr.

(2012) Reactivity of CO2 in the Subsurface. USGS CO2 Sequestration in Unconventional Reservoirs Workshop, Shepherdstown, WV March 2012

Kang, S–H., Johnson, N. C., Thomas, B., Maher, K., Bird, D. K., Rosenbauer, R. J., Brown Jr., G. E. (2012) Effect of oxalic acid on geological storage of CO2 using serpentinite. Goldschmidt Conference, Montréal, Canada.

García del Real, P., Maher, K., Bird, D.K., and Brown, G. E. Jr. (2012) Large magnesite vein and fracture formation in peridotite rocks. Goldschmidt Conference, Montréal, Canada.

(Invited) García del Real, P. (2012) From the ocean floor to the continental crust: Peridotite rocks and their implications to past and present life. Astronomy, Physics, and Engineering Departments Seminars, American River College, Sacramento, CA.

(Invited) Maher, K., Johnson, N. C., García Del Real, P., Thomas B., Bird, D. K., Rosenbauer, R. Brown, G. E. Jr. (2011) Reactivity of CO2 in the subsurface, GCEP Annual Meeting, Stanford, California.

Johnson, N. C., Thomas B., Maher, K., Bird, D. K., Rosenbauer, R. Brown, G. E. Jr. CO2 (2011) Effect of a Si-rich layer on olivine carbonation under in-situ conditions, presented at 2011 Fall Meeting, AGU, San Francisco, Calif., 13–17 Dec.

Johnson, N. C., Thomas, B., Maher, K., Bird, D. K., Rosenbauer, R. Brown, G. E. Jr. (2011) CO2 Sequestration Using Direct Mineral Carbonation of Mg-Silicates Precourt Institute Advisory Board Meeting.

(Invited) García del Real, P., Maher, K., Bird, D.K., and Brown, G. E. Jr. (2011) Curbing atmospheric concentrations of CO2: Capture and storage in peridotite rocks.

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Interdisciplinary Innovation in the Energy Space Discussion, Stanford Graduate School of Business, Stanford, CA.

Johnson, N. C., Thomas, B., Maher, K., Bird, D. K., Rosenbauer, R. Brown, G. E. Jr. (2011) Adsorption of organic ligands on silicate mineral surfaces in the presence of CO2 and water: Insight into olivine dissolution rates. Goldschmidt Conference, Prague, Czech Republic.

Johnson N. C., Thomas B., Maher K., Bird D. K., Rosenbauer R. J., Brown G. E. Jr. (2011) Kinetics of olivine carbonation for carbon sequestration. Carbon Capture and Storage Oman, Muscat, Sultanate of Oman, 8-10 Jan.

García Del Real, P., Maher, K., Bird, D.K., and Brown, G.E. Jr.(2011), CO2 Sequestration in Ultramafic Rocks: Insights from the Red Mountain Magnesite District, California, Geological Carbon Capture and Storage, Muscat, Sultanate of Oman, 8-10 Jan.

García Del Real, P. Maher, K., Bird, D. K., Brown, G.E. Jr. (2010) CO2 Sequestration in ultramafic rocks: insights from the Red Mountain Magnesite District, California. Abstract EP41C-0719 presented at 2010 Fall Meeting, AGU, San Francisco, Calif., 13–17 Dec.

(Invited) Maher, K., García del Real, P., Bird, D. K., Brown, G. E. Jr., Johnson, N., Kharaka, Y. K., Rosenbauer, R. J. (2010) Discrepancies between laboratory and field-based mineral-fluid reaction rates: implications for CO2 sequestration based on reactive transport studies of natural systems. Geological Society of America Fall Meeting, Denver, CO. GSA Abstracts with Programs Vol. 42, No. 5.

Johnson, N. C, B. Thomas, K. Maher, T. Kendelewicz, D. K. Bird, R. B. Rosenbauer, and G. E. Brown, Jr. (2010) Kinetics of Mg-silicate carbonation for the geologic storage��� of carbon dioxide. Abstr. ACS Ann. Mtg., San Francisco, CA.

Johnson, N. C, B. Thomas, K. Maher, D. K. Bird, R. B. Rosenbauer, and G. E. Brown, Jr. (2009) Kinetics of olivine carbonation at 60°C and 100 bar. Abstr. Prog. Geol. Soc. Am. Ann. Mtg., Portland, OR.

Contacts

Kate Maher: kmaher@stanford.edu Gordon E. Brown, Jr.: gordon.brown@stanford.edu Dennis K. Bird: dkbird@stanford.edu Robert J. Rosenbauer: brosenbauer@usgs.gov Burt Thomas: burt_thomas@usgs.gov Natalie Johnson: nataliej@stanford.edu Pablo García Del Real: gdelreal@stanford.edu Seung-Hee Kang: envlover@stanford.edu Joseph Nelson: jnelson1@stanford.edu Dana Thomas: danat@stanford.edu

References

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