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Ketzer, João MarceloORCID iD iconorcid.org/0000-0003-4796-8177
Publications (10 of 38) Show all publications
Cedeno, D. G., Conceicao, R. V., Wilbert de Souza, M. R., Schimdt Quinteiro, R. V., Carniel, L. C., Ketzer, J. M., . . . Bruzza, E. d. (2019). An experimental study on smectites as nitrogen conveyors in subduction zones. Applied Clay Science, 168, 409-420
Open this publication in new window or tab >>An experimental study on smectites as nitrogen conveyors in subduction zones
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2019 (English)In: Applied Clay Science, ISSN 0169-1317, E-ISSN 1872-9053, Vol. 168, p. 409-420Article in journal (Refereed) Published
Abstract [en]

We performed high pressure and high temperature (HPHT) experiments on NH4-doped montmorillonite (similar to 2 wt % of NH4) under pressures of 2.5, 4.0, and 7.7 GPa and temperatures from 200 to 700 degrees C. Each experiment was analyzed with XRD, FTIR, CHN elemental analysis, and SEM in order to determine the NH4-Smectite phase changes and their morphology, and the presence of ammonium in the runs. Our results show that smectite can easily transport nitrogen, speciated as ammonium (NH4+), incorporated into the smectite interlayer in mildly reducing environments to deeper levels in the Earth through cold thermal regime subduction zones. NH4-Smectite transforms into NH4-enriched micaceous phase (tobelite) through a NH4+-enriched interlayered I/S phase in relatively low pressures and temperatures (around 2.5 GPa and 500 degrees C). Tobelite is stable until more extreme conditions (7.7 GPa and 700 degrees C), together with lesser amounts of buddingtonite (an ammonium-bearing feldspar) kyanite, and garnet. Our experiments also show the effect of nitrogen in the feldspar stability, as potassic and sodic feldspar are stable up to similar to 5 GPa, while buddingtonite, is observed to be stable up to 7.7 GPa. Nitrogen can return to the surface once the stability of these nitrogen-enriched minerals is reached due to pressure or temperature increasing.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Nitrogen, Subduction zones, Ammonium, Pelagic sediments
National Category
Earth and Related Environmental Sciences
Research subject
Natural Science, Environmental Science
Identifiers
urn:nbn:se:lnu:diva-80729 (URN)10.1016/j.clay.2018.11.006 (DOI)000455692700044 ()
Available from: 2019-02-20 Created: 2019-02-20 Last updated: 2019-02-20Bibliographically approved
Stranne, C., O’Regan, M., Jakobsson, M., Brüchert, V. & Ketzer, J. M. (2019). Can anaerobic oxidation of methane prevent seafloor gas escape in a warming climate?. Solid Earth Discussions
Open this publication in new window or tab >>Can anaerobic oxidation of methane prevent seafloor gas escape in a warming climate?
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2019 (English)In: Solid Earth Discussions, ISSN 1869-9537Article in journal (Refereed) Submitted
Abstract [en]

Abstract. Assessments of future climate warming-induced seafloor methane (CH4) release rarely include anaerobic oxidation of methane (AOM) within the sediments. Considering that more than 90 % of the CH4 produced in ocean sediments today is consumed by AOM, this may result in substantial overestimations of future seafloor CH4 release. Here we integrate a fully coupled AOM module with a numerical hydrate model to investigate under what conditions rapid release of CH4 can bypass AOM and result in significant fluxes to the ocean and atmosphere. The results presented in this study should be seen as a first step towards understanding AOM dynamics in relation to climate change and hydrate dissociation. Although the model is somewhat poorly constrained, our results indicate that vertical CH4 migration through hydraulic fractures can result in low AOM efficiencies. Fracture flow is the predicted mode of methane transport under warming-induced dissociation of hydrates on upper continental slopes. Therefore, in a future climate-warming scenario, AOM might not significantly reduce methane release from marine sediments.

Place, publisher, year, edition, pages
Copernicus GmbH, 2019
National Category
Earth and Related Environmental Sciences
Research subject
Natural Science
Identifiers
urn:nbn:se:lnu:diva-81673 (URN)10.5194/se-2019-50 (DOI)
Note

In review 20100410

Available from: 2019-04-04 Created: 2019-04-04 Last updated: 2019-04-10
Ketzer, J. M., Praeg, D., Pivel, M., Augustin, A., Rodrigues, L. F., Viana, A. & Cupertino, J. (2019). Gas Seeps at the Edge of the Gas Hydrate Stability Zone on Brazil’s Continental Margin. Geosciences, 9(5), 1-11, Article ID 193.
Open this publication in new window or tab >>Gas Seeps at the Edge of the Gas Hydrate Stability Zone on Brazil’s Continental Margin
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2019 (English)In: Geosciences, E-ISSN 2076-3263, Vol. 9, no 5, p. 1-11, article id 193Article in journal (Refereed) Published
Abstract [en]

Gas hydrate provinces occur in two sedimentary basins along Brazil’s continental margin: (1) The Rio Grande Cone in the southeast, and (2) the Amazon deep-sea fan in the equatorial region. The occurrence of gas hydrates in these depocenters was first detected geophysically and has recently been proven by seafloor sampling of gas vents, detected as water column acoustic anomalies rising from seafloor depressions (pockmarks) and/or mounds, many associated with seafloor faults formed by the gravitational collapse of both depocenters. The gas vents include typical features of cold seep systems, including shallow sulphate reduction depths (<4 m), authigenic carbonate pavements, and chemosynthetic ecosystems. In both areas, gas sampled in hydrate and in sediments is dominantly formed by biogenic methane. Calculation of the methane hydrate stability zone for water temperatures in the two areas shows that gas vents occur along its feather edge (water depths between 510 and 760 m in the Rio Grande Cone and between 500 and 670 m in the Amazon deep-sea fan), but also in deeper waters within the stability zone. Gas venting along the feather edge of the stability zone could reflect gas hydrate dissociation and release to the oceans, as inferred on other continental margins, or upward fluid flow through the stability zone facilitated by tectonic structures recording the gravitational collapse of both depocenters. The potential quantity of venting gas on the Brazilian margin under different scenarios of natural or anthropogenic change requires further investigation. The studied areas provide natural laboratories where these critical processes can be analyzed and quantified.

Place, publisher, year, edition, pages
MDPI, 2019
National Category
Earth and Related Environmental Sciences
Research subject
Natural Science, Environmental Science
Identifiers
urn:nbn:se:lnu:diva-82324 (URN)10.3390/geosciences9050193 (DOI)000470966100002 ()
Available from: 2019-04-28 Created: 2019-04-28 Last updated: 2019-07-15Bibliographically approved
Rodrigues, F., Ramos, A., Araujo, G., Silveira, E., Ketzer, M. & Lourega, R. (2019). High-Pressure and Automatized System for Study of Natural Gas Hydrates. Energies
Open this publication in new window or tab >>High-Pressure and Automatized System for Study of Natural Gas Hydrates
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2019 (English)In: Energies, ISSN 1996-1073, E-ISSN 1996-1073Article in journal (Refereed) Published
National Category
Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:lnu:diva-87300 (URN)10.3390/en12163064 (DOI)
Available from: 2019-08-09 Created: 2019-08-09 Last updated: 2019-08-09
Rodrigues, L., Ketzer, J. M., Oliveira, R., dos Santos, V., Augustin, A., Cupertino, J., . . . Dorle, W. (2019). Molecular and Isotopic Composition of Hydrate-Bound, Dissolved and Free Gases in the Amazon Deep-Sea Fan and Slope Sediments, Brazil. Geosciences, 9(2), 1-15, Article ID 73.
Open this publication in new window or tab >>Molecular and Isotopic Composition of Hydrate-Bound, Dissolved and Free Gases in the Amazon Deep-Sea Fan and Slope Sediments, Brazil
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2019 (English)In: Geosciences, ISSN 2076-3263, Vol. 9, no 2, p. 1-15, article id 73Article in journal (Refereed) Published
Abstract [en]

In this work, we investigated the molecular stable isotope compositions of hydrate-bound and dissolved gases in sediments of the Amazon deep-sea fan and adjacent continental slope, Foz do Amazonas Basin, Brazil. Some cores were obtained in places with active gas venting on the seafloor and, in one of the locations, the venting gas is probably associated with the dissociation of hydrates near the edge of their stability zone. Results of the methane stable isotopes (δ13C and δD) of hydrate-bound and dissolved gases in sediments for the Amazon fan indicated the dominant microbial origin of methane via carbon dioxide reduction, in which 13C and deuterium isotopes were highly depleted (δ13C and δD of −102.2% to −74.2% V-PDB and −190 to −150% V-SMOW, respectively). The combination of C1/(C2+C3) versus δ13C plot also suggested a biogenic origin for methane in all analysed samples (commonly >1000). However, a mixture of thermogenic and microbial gases was suggested for the hydrate-bound and dissolved gases in the continental slope adjacent to the Amazon fan, in which the combination of chemical and isotopic gas compositions in the C1/(C2+C3) versus δ13C plot were <100 in one of the recovered cores. Moreover, the δ13C-ethane of −30.0% indicates a thermogenic origin.

Place, publisher, year, edition, pages
MDPI, 2019
National Category
Earth and Related Environmental Sciences
Research subject
Natural Science, Environmental Science
Identifiers
urn:nbn:se:lnu:diva-80085 (URN)10.3390/geosciences9020073 (DOI)000460761900018 ()
Available from: 2019-01-31 Created: 2019-01-31 Last updated: 2019-03-29Bibliographically approved
Iglesias, R. S., Ketzer, J. M., Maraschin, A. J. & Sbrissa, G. (2018). Characterization and modeling of CO2‐water‐rock interactions in Hygiene Sandstones (Upper Cretaceous), Denver Basin, aimed for carbon dioxide geological storage. Greenhouse Gases: Science and Technology, 8(4), 781-795
Open this publication in new window or tab >>Characterization and modeling of CO2‐water‐rock interactions in Hygiene Sandstones (Upper Cretaceous), Denver Basin, aimed for carbon dioxide geological storage
2018 (English)In: Greenhouse Gases: Science and Technology, E-ISSN 2152-3878, Vol. 8, no 4, p. 781-795Article in journal (Refereed) Published
Abstract [en]

Carbon capture and geological storage are among the most valuable technologies capable of reducing CO2 emissions. Long‐term interactions between CO2 and a reservoir, and the integrity of geological formations, are key factors in the selection of adequate reservoirs for permanent storage. Numerical models of CO2‐water‐rock geochemical interactions are often employed to predict the fate of CO2 stored in a reservoir over time. The Hygiene Sandstone, in the Denver Basin, Colorado, USA, is a geological formation with potential for CO2 storage, and was therefore studied in this work, in which we collected and characterized outcrop samples in order to supply the input parameters for numerical simulations. Four representative thin sections of Hygiene Sandstone outcrops were quantified in terms of detrital constituents, diagenesis, and porosity on the basis of conventional petrography. Sandstone mineralogy included, in decreasing order, quartz, K‐feldspar, muscovite, albite, illite, smectite, kaolinite, poikilotopic calcite, and siderite. Porosity ranged from 4% to 13%. A geochemical modeling study of CO2‐water‐rock interactions performed with two characterized samples and brine data from the Hygiene Sandstones, simulating reservoir conditions, suggested that the mineralogy of the sandstone is quite stable under the conditions that were tested and only minor mineralogical and porosity alterations would occur within a thousand years of storage.

Place, publisher, year, edition, pages
Wiley-Blackwell, 2018
National Category
Earth and Related Environmental Sciences
Research subject
Natural Science
Identifiers
urn:nbn:se:lnu:diva-75696 (URN)10.1002/ghg.1788 (DOI)000440549700012 ()
Available from: 2018-06-12 Created: 2018-06-12 Last updated: 2019-02-22Bibliographically approved
da S. Ramos, A., de Araujo, G. E., Siviero, L., Ketzer, J. M., Heemann, R., Lourega, R. V. & Rodrigues, L. F. (2018). Comparative assessment between different sample preparation methodologies for PTGA CO2 adsorption assays—Pellet, powder, and fragment samples. Adsorption Science and Technology, 36(7-8), 1441-1455
Open this publication in new window or tab >>Comparative assessment between different sample preparation methodologies for PTGA CO2 adsorption assays—Pellet, powder, and fragment samples
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2018 (English)In: Adsorption Science and Technology, ISSN 0263-6174, E-ISSN 2048-4038, Vol. 36, no 7-8, p. 1441-1455Article in journal (Refereed) Published
Abstract [en]

The carbon dioxide sorption process at coal seams is very important for understanding the trapping mechanisms of carbon capture and storage. The gas retention capacity of coal seams can be estimated using indirect methods based on the adsorption/desorption isotherms obtained in the laboratory. However, the gas sorption capacity can be overestimated or underestimated depending on the sample preparation. This work evaluates different sample preparations and their theoretical adsorption capacity using coal samples from the Cambui coal field (Parana Basin), southern Brazil. Experiments using a thermogravimetric balance were done to calculate the theoretical adsorption capacity, while sample characterization was done through immediate analysis, elementary analysis, and mineralogical studies. The sample preparations used in this work were powder, pellets, and fragments. While the powder form presents an average behavior, without any experimental complication, the pellet is extremely sensitive to any variation in the sample preparation, such as fractures, and the fragment requires a much longer experiment time than the other sample preparations, being impracticable for some cases.

Place, publisher, year, edition, pages
Sage Publications, 2018
Keywords
Thermogravimetric balance, coal, carbon dioxide, adsorption, Pressurized ThermoGravimetric Analyzer (PTGA)
National Category
Analytical Chemistry
Research subject
Natural Science, Chemistry
Identifiers
urn:nbn:se:lnu:diva-74747 (URN)10.1177/0263617418779459 (DOI)
Available from: 2018-05-30 Created: 2018-05-30 Last updated: 2019-05-20Bibliographically approved
Engelmann, P. d., dos Santos, V. H., Barbieri, C. B., Augustin, A. H., Ketzer, J. M. & Rodrigues, L. F. (2018). Environmental monitoring of a landfill area through the application of carbon stable isotopes, chemical parameters and multivariate analysis. Waste Management, 76, 591-605
Open this publication in new window or tab >>Environmental monitoring of a landfill area through the application of carbon stable isotopes, chemical parameters and multivariate analysis
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2018 (English)In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 76, p. 591-605Article in journal (Refereed) Published
Abstract [en]

Leachate produced during an organic matter decomposition process has a complex composition and can cause contamination of surface and groundwaters adjacent to a landfill area. The monitoring of these areas is extremely important for the characterization of the leachate produced and to avoid or mitigate environmental damages. Thus, the present study has the objective of monitoring the area of a Brazilian landfill using conventional parameters (dissolved metals and anions in water) and alternative, stable carbon isotopes parameters (δ13C of dissolved organic and inorganic carbons in water) in addition to multivariate analysis techniques. The use of conventional and alternative parameters together with multivariate analysis showed that cells of the residues are at different phases of stabilization of the organic matter and probably already at C3 of the methanogenic phase of decomposition. In addition, the data showed that organic matter stabilization ponds present in the landfill are efficient and improve the quality of the leachate. Enrichment of the heavy 13C isotope in both surface and groundwater suggested contamination in two sampling sites.

National Category
Earth and Related Environmental Sciences
Research subject
Natural Science
Identifiers
urn:nbn:se:lnu:diva-74540 (URN)10.1016/j.wasman.2018.02.027 (DOI)
Available from: 2018-05-25 Created: 2018-05-25 Last updated: 2019-05-20Bibliographically approved
Ketzer, J. M., Augustin, A., Rodrigues, L. F., Oliveira, R., Praeg, D., Gomez Pivel, M. A., . . . Leonel, B. (2018). Gas seeps and gas hydrates in the Amazon deep-sea fan. Geo-Marine Letters, 38(5), 429-438
Open this publication in new window or tab >>Gas seeps and gas hydrates in the Amazon deep-sea fan
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2018 (English)In: Geo-Marine Letters, ISSN 0276-0460, E-ISSN 1432-1157, Vol. 38, no 5, p. 429-438Article in journal (Refereed) Published
Abstract [en]

Deep-sea fans have been proposed to act as carbon sinks, rapid deposition driving shallow methanogenesis to favor net storage within the gas hydrate stability zone (GHSZ). Here, we present new evidence of widespread gas venting from the GHSZ on the upper Amazon deep-sea fan, together with analyses of the first samples of gas hydrates recovered offshore NE Brazil. Multibeam water column and seafloor imagery over an 18,000-km2 area of the upper Amazon fan reveal 53 water column gas plumes, rising from venting features in water depths of 650–2600 m. Most gas vents (60%) are located along seafloor faults that record the ongoing gravitational collapse of the fan above deep décollements, while others (40%) are located in water depths of 650–715 m within the upper edge of the GHSZ. Gas compositions from hydrates recovered in vents at three locations on and north of the fan indicate biogenic sources (dominantly methane with 2–15% of CO2; δ13C from − 81.1 to − 77.3‰), whereas samples from vents adjacent to the fan proper include possible thermogenic contributions (methane 95%, CO2 4%, and ethane 1%; δ13C – 59.2‰). These results concur with previous findings that the upper edge of the GHSZ may be sensitive to temporal changes in water temperatures, but further point to the importance of gas escape from within areas of gas hydrate stability. Our results suggest the role of fluid migration along pathways created by faulting within rapidly deposited passive margin depocenters, which are increasingly recognized to undergo gravitational collapse above décollements. Our findings add to evidence that gas can escape from sediments to the sea in areas where gas hydrates are stable on passive margins, and suggest the need of further studies of the dynamics of deep-sea depocenters in relation to carbon cycling.

Place, publisher, year, edition, pages
Springer, 2018
National Category
Earth and Related Environmental Sciences
Research subject
Natural Science
Identifiers
urn:nbn:se:lnu:diva-77182 (URN)10.1007/s00367-018-0546-6 (DOI)000446101900004 ()
Available from: 2018-08-17 Created: 2018-08-17 Last updated: 2019-02-22Bibliographically approved
Schütz, M. K., Lopes, N. F., Cenci, A., Ketzer, J. M., Einloft, S., Dullius, J. & Ligabue, R. (2018). Influence of Alkaline Additives and Buffers on Mineral Trapping of CO2 under Mild Conditions. Chemical Engineering & Technology, 41(3), 573-579
Open this publication in new window or tab >>Influence of Alkaline Additives and Buffers on Mineral Trapping of CO2 under Mild Conditions
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2018 (English)In: Chemical Engineering & Technology, ISSN 0930-7516, E-ISSN 1521-4125, Vol. 41, no 3, p. 573-579Article in journal (Refereed) Published
Abstract [en]

Carbon dioxide (CO2) gas is the main contributor to climate change. CO2 storage in underground brines and oil‐field brines by mineral trapping has been considered as a promising alternative in order to reduce CO2 emissions. However, permanent storage of CO2 in stable carbonate minerals is greatly dependent on brine pH, being favored over an alkaline pH. The effect of alkaline additives (NaOH, KOH, CaO) and buffer solutions (NaHCO3/NaOH, Na2HPO4/NaOH, NH4Cl/NH4OH) on the mineral trapping of CO2 under mild conditions using a synthetic brine is investigated. The results indicate that both NaOH+NH4Cl/NH4OH and KOH+NH4Cl/NH4OH mixtures promote precipitation mainly of calcium carbonate (CaCO3).

National Category
Chemical Engineering
Research subject
Natural Science, Environmental Science
Identifiers
urn:nbn:se:lnu:diva-74539 (URN)10.1002/ceat.201600513 (DOI)
Available from: 2018-05-25 Created: 2018-05-25 Last updated: 2019-05-20Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0003-4796-8177

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