TY - CHAP AU - Karlik, Máté AU - Törőcsik, GT AU - Bozsó, Gábor AU - Fekete, József ED - Fehér, Béla ED - Molnár, Kata ED - Haranginé Lukács, Réka ED - Czuppon, György ED - Kereskényi, Erika TI - Környezetrekonstrukció geokémiai vizsgálatok segítségével a Bolatau-Feredeu tó 500 éves üledékén T2 - Calce et malleo – Mésszel és kalapáccsal PB - Csillagászati és Földtudományi Kutatóközpont CY - Budapest SN - 9789637331008 PY - 2022 SP - 67 EP - 68 PG - 2 UR - https://m2.mtmt.hu/api/publication/33116823 ID - 33116823 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Karlik, Máté AU - Vancsik, Anna AU - Szalai, Zoltán AU - Mîndrescu, M AU - Grădinaru, I AU - Vágási, S AU - Bozsó, Gábor AU - Fekete, József TI - Natural and anthropogenic impacts reflected by paleoclimate proxy parameters in a lake-forest system in Bukovina, Romania JF - HUNGARIAN GEOGRAPHICAL BULLETIN (2009-) J2 - HUNG GEOGR BULL (2009-) VL - 70 PY - 2021 IS - 4 SP - 339 EP - 351 PG - 13 SN - 2064-5031 DO - 10.15201/hungeobull.70.4.4 UR - https://m2.mtmt.hu/api/publication/32535952 ID - 32535952 N1 - Export Date: 8 December 2022 Correspondence Address: Karlik, M.; Institute for Geological and Geochemical Research, Budaörsi út 45, Hungary; email: karlik.mate@csfk.org LA - English DB - MTMT ER - TY - JOUR AU - Biondi, CJ AU - Polgári, Márta Piroska AU - Gyollai, Ildikó AU - Fintor, Krisztián AU - Kovács, Ivett AU - Fekete, József AU - Mojzsis, Stephen, James TI - Biogenesis of the neoproterozoic kremydilite manganese ores from urucum (brazil) – a new manganese ore type JF - PRECAMBRIAN RESEARCH J2 - PRECAMBRIAN RES VL - 340 PY - 2020 PG - 27 SN - 0301-9268 DO - 10.1016/j.precamres.2020.105624 UR - https://m2.mtmt.hu/api/publication/31143179 ID - 31143179 AB - The Urucum district in Mato Grosso do Sul (Brazil), hosts the youngest and largest sedimentary Mn ore of Neoproterozoic age; units Mn-1, Mn-2, and Mn-3 are found in jaspilites and ironstones, and represent approximately 600 Mt of extractable rock with 27-44% Mn and 12-30% Fe. High-resolution optical- and cathodoluminescence microscopy, as well as Raman and FTIR spectroscopy show that the lower Mn-1 is ferruginous, while the upper Mn-1 consists mainly of 30-75 vol% braunite, < 0.5% aegirine, 3-15% quartz, 5-10% feldspar, and 1-5% clay minerals, including apatite, chlorite, and organic matter. Here, we model the control of this ore mineralogy by homogeneous oxidation and microbial processes. Layers Mn-2 and Mn-3 contain kremydilite, as a characteristic ore structure, with 77-95 vol% cryptomelane, 0-23% hollandite, 9-19% braunite, 7-21% hematite, and 0-5% pores filled with clay minerals and organic matter. These are present within a micro-nodule matrix composed of cryptomelane and hematite in varying proportions. The first syngenetic products of microbial enzymatic oxidation were, on the Fe side, ferrihydrite and lepidocrocite, and on the Mn side, vernadite, todorokite, birnessite, and manganite. These formed under obligatory oxic (Mn) and suboxic (Fe) conditions and close to neutral pH. We describe the genesis of Urucum via complex diagenetic processes, which include the decomposition and mineralization of cellular- and extracellular-polymeric substances from Fe and Mn bacteria and cyanobacteria. The kremydilite forms in successive stages of oxidation of organic matter mediated by microbes, which generate pores and produce methane and CO2/H-2 bubbles. They are a unique type of diagenetic structure formed by heterotrophic cell colonies randomly activated in the microbialite milieu following burial in suboxic neutral/alkaline conditions, side-by-side with the lithification and stabilization of the mineral assemblages.Significance statement The Neoproterozoic Urucum manganese deposit (Brazil) is a similar to 600 Mt microbially-mediated sedimentary Mn ore. Proto-ore formation via sedimentation and diagenesis occurred under suboxicoxic-oxic and semi-neutral pH conditions in the Ediacaran ocean, wherein microbial Mn(II) oxidation ensued from the fine-grained accumulation of Mn oxides and organic matter. Oxic conditions that facilitated enzymatic Mn oxidation and overwhelmed microbial Fe oxidation appears as a sharp contact between manganese and iron beds. The Urucum deposit arose from a complex suite of diagenetic processes, including decomposition and mineralization of microbially-derived organic matter involving extracellular polymeric substances. Kremydilite - a new type of diagenetic concentric Mn mineral structure formed by randomly activated heterotrophic cell colonies that generated pores in the microbialite sediment after burial, coincident with lithification. LA - English DB - MTMT ER - TY - CONF AU - Körmös, Sándor AU - Fekete, József AU - Milota, Katalin AU - Schubert, Félix TI - Hydrocarbon generation potential of Paleogene sediments in the Hungarian Paleogene Basin T2 - AAPG Europe Regional Conference, 2019: Paratethys Petroleum Systems Between Central Europe and the Caspian Region : Book of Abstracts PY - 2019 SP - 118 UR - https://m2.mtmt.hu/api/publication/30753152 ID - 30753152 LA - English DB - MTMT ER - TY - JOUR AU - Yu, W AU - Polgári, Márta Piroska AU - Gyollai, Ildikó AU - Fintor, Krisztián AU - Szabó, Máté Zoltán AU - Kovács, Ivett AU - Fekete, József AU - Du, Y AU - Zhou, Qi TI - Microbial metallogenesis of Cryogenian manganese ore deposits in South China JF - PRECAMBRIAN RESEARCH J2 - PRECAMBRIAN RES VL - 322 ET - 0 PY - 2019 SP - 122 EP - 135 PG - 14 SN - 0301-9268 DO - 10.1016/j.precamres.2019.01.004 UR - https://m2.mtmt.hu/api/publication/30393777 ID - 30393777 N1 - State Key Laboratory of Biogeology and Environmental Geology, School of Earth Sciences, China University of Geosciences, Wuhan, 430074, China Institute for Geological and Geochemical Research, RCAES, Hungarian Academy of Sciences, 1112 Budapest, Budaörsi str. 45, Hungary Eszterházy Károly University, Department of Natural Geography and Geoinformatics, 3300 Eger, Leányka str. 6, Hungary Szeged University, Dept. of Mineralogy, Geochemistry and Petrology, 6722 Szeged, Egyetem, str. 2-6, Hungary Guizhou Bureau of Geology and Mineral Exploration and Development, Guiyang, 550004, China Cited By :37 Export Date: 21 April 2023 CODEN: PCBRB Correspondence Address: Du, Y.; State Key Laboratory of Biogeology and Environmental Geology, China; email: duyuansheng126@126.com LA - English DB - MTMT ER - TY - CHAP AU - Karlik, Máté AU - Gyollai, Ildikó AU - Fekete, József AU - Mindrescu, M AU - Grădinaru, I AU - Kovács, János AU - Polgári, Márta Piroska TI - MICROBIAL FOOTPRINT IN LAKE SEDIMENTS FROM CENTRAL EUROPE T2 - 20th International Sedimentological Congress, SN - 9782891469364 PY - 2018 SP - 1 UR - https://m2.mtmt.hu/api/publication/32868891 ID - 32868891 LA - English DB - MTMT ER - TY - CHAP AU - Karlik, Máté AU - Gyollai, Ildikó AU - Fekete, József AU - Bozsó, Gábor AU - Fintor, Krisztián AU - Polgári, Márta Piroska ED - Neubauer, F ED - Brendel, U ED - Friedl, G TI - High-resolution sedimentology study of laminated lake sediment fromEast Carpathian Mountains, Romania T2 - XXI International Congress of the CBGA, Abstracts: Advances of Geology in southeast European mountain belts PB - Bulgarian Academy of Sciences (BAS) CY - Salzburg SN - 9789549022384 PY - 2018 SP - 115 PG - 1 UR - https://m2.mtmt.hu/api/publication/3419614 ID - 3419614 LA - English DB - MTMT ER - TY - JOUR AU - Karlik, Máté AU - Fekete, József AU - Mindrescu, M AU - Grădinaru, I AU - Bozsó, Gábor AU - Biró, Lóránt AU - Kern, Zoltán TI - Natural and anthropogenic changes in a lake-forest system in Bukovina (Romania) since 1340 AD documented by sedimentary organic geochemistry (C, N and n-alkanes) JF - QUATERNARY INTERNATIONAL J2 - QUATERN INT VL - 493 PY - 2018 SP - 166 EP - 175 PG - 10 SN - 1040-6182 DO - 10.1016/j.quaint.2018.06.008 UR - https://m2.mtmt.hu/api/publication/3392243 ID - 3392243 N1 - Funding Agency and Grant Number: European Union; State of Hungary; European Regional Development Fund [GINOP-2.3.2.-15-2016-00009]; National Research, Development and Innovation Office [K125060]; [LP2012-27/2012]\n Funding text: The research was supported by the European Union and the State of Hungary, co-financed by the European Regional Development Fund in the project of GINOP-2.3.2.-15-2016-00009 ICER. Thanks for the financial support of the National Research, Development and Innovation Office (K125060) and LP2012-27/2012. This is contribution No. 60 of 2ka Palaeoclimatology Research Group.\n AB - Lake Bolatau-Feredeu is a small (surface: 0.3 ha; catchment area: 31 ha) landslide-dammed lake in Bukovina (Eastern Carpathians, Romania). Elemental concentration, stable isotope composition of carbon and nitrogen, and n-alkane composition of the saturated hydrocarbon fraction of the organic material were analyzed along the sediment profile from Lake Bolatau-Feredeu covering the past 700 years. The ranges of delta C-13 values (- 30.5 to - 26.6 parts per thousand) and C/N atomic ratios (10.5 and 15.4) placed the organic material of the recent Bolatau-Feredeu sediment between the C3 Land Plants and the lacustrine algae. The n-alkane proxies provide better distinction between organic matter inputs. Detected major shifts in the n-alkane composition and the C and N concentrations along with the stable isotope compositions pointed towards three distinct stages in the environmental history of the lake-catchment system. The proxy information indicate a substantial landscape change characterized by deforestation and an increase in open pastureland with herbaceous vegetation from similar to 1820. The C/N, delta N-15, and delta C-13 values showed the highest variability probably linked to a variable lacustrine environment and decreased productivity in the catchment between similar to 1640 and 1760. It can be assumed that the extended periods of lake ice cover during the cold decades experienced at the turn of the 17th -18th centuries resulted in diminished biological productivity both in the lake and its catchment. Finally, afforestation and the decline in lake productivity have been reconstructed for the period of - 1470-1560. LA - English DB - MTMT ER - TY - CONF AU - Sajgó, Csanád AU - Fekete, József TI - Effect of CO2 on δ13C and δD isotope type-curves of oils and condensates during migration (NW Pannonian Basin, Hungary) T2 - 28th International Meeting on Organic Geochemistry PY - 2017 PG - 1 UR - https://m2.mtmt.hu/api/publication/3315667 ID - 3315667 LA - English DB - MTMT ER - TY - CONF AU - Fekete, József AU - Sajgó, Csanád TI - Cracking kinetics of pristane and phytane in a set of crude oils from the Pannonian Basin (Hungary) T2 - 28th International Meeting on Organic Geochemistry PY - 2017 PG - 1 UR - https://m2.mtmt.hu/api/publication/3315666 ID - 3315666 LA - English DB - MTMT ER -