@article{MTMT:35680471, title = {Volcanic history and magma systems of Lake Monoun Polygenetic Maar, Noun Plain, Western part of the Cameroon Volcanic Line: Constraints from stratigraphy, chronology and geochemistry}, url = {https://m2.mtmt.hu/api/publication/35680471}, author = {Nche, Linus Anye and Hasegawa, Takeshi and Aka, Festus Tongwa and Ohba, Takeshi and Mafany, George Teke and Németh, Károly and Miyabuchi, Yasuo and Kaneda, Yasuaki and Asaah, Asobo Nkengmatia Elvis and Wajiba, Patrick Mendi and Ngwa, Caroline Neh and Tchop, Joseph Legrand and Nguet, Pauline Wokwenmendam and Nfomou, Ntepe and Suh, Cheo Emmanuel and Fantong, Wilson Yetoh and Mouncherou, Farouk Oumar}, doi = {10.1016/j.jvolgeores.2025.108265}, journal-iso = {J VOLCANOL GEOTH RES}, journal = {JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH}, unique-id = {35680471}, issn = {0377-0273}, abstract = {Lake Monoun (LM) is a maar volcano located on the Cameroon Volcanic Line in West-Central Africa. In 1984, a limnic eruption occurred at LM, releasing large amounts of magmatic CO2 gas that had accumulated in the lake. The CO2 gas asphyxiated 37 people in the surrounding area. Despite this hazard, the volcanic history of LM maar remains unknown. This study presents the first comprehensive results of lithostratigraphy, physical volcanology, 14C dating and petrology of LM eruptive products. The lake has a WSW-ENE-aligned morphology with three main craters, the walls of which expose tephra and lava that can be divided into 5 stratigraphic units (A, B, C, D, and E from bottom to top). Unit A, a pyroclastic surge deposit in the NW, was produced by a phreatomagmatic eruption and deposited on a thick (ca.170 cm) paleosol developed on granitic basement. The paleosol yields a 14C age of ca 1.3 cal. ka. Units B (weathered scoria fall) and C (lava flow) in the NW part of the lake were respectively produced by strombolian and effusive eruptive activities. The SE side consists of unit D (scoria fall) a product of violent strombolian activity and unit E (voluminous surge) deposited by phreatomagmatic activity. The surge deposits of units A and E are rich in lithic fragments such as granite and lava, indicating subterranean excavation of country (accidental) and volcanic (accessory) rocks. A short time break represented by thin (ca. 15 cm, 0.1–0.3 cal. ka) paleosol can be recognized between units A and E in the distal facies. Based on the temporal and spatial distribution of these deposits, the eruption history of LM can be grouped into two stages. The first stage led to the development of the western and central craters and is recorded by units A to C in the NE section. The second stage proceeded after a short hiatus represented by the thin paleosol and a shift of the eruptive locus to the SE part of the lake. This gave rise to the largest eastern crater characterized by well-preserved units D and E. The LM case study reveals a potential time-space evolutionary pathway for crater formation, implying a polygenetic origin. Juvenile materials from the units are basanitic in composition with narrow chemical variation, suggesting a common magma system through the two stages. Silica content gradually increases from units A to E (SiO2 = 43.4 to 45.8 wt%), suggesting that the magma was differentiated with time (from units A to E) and tapped from the whole part of the chamber at unit E. Accessory lava fragments in units A and E display three distinct geochemical trends, composed of alkali and subalkaline basalts, implying the presence of diverse magma systems around the area prior to the maar formation.}, keywords = {polygenetic; Geochemistry; Volcanic stratigraphy; Lake Monoun Maar; Cameroon Volcanic Line (CVL); Juvenile and accessory clasts}, year = {2025}, eissn = {1872-6097}, pages = {108265} } @CONFERENCE{MTMT:35742522, title = {Evolution and polycyclic nature of a maar-diatreme volcano as constrained by changing external factors}, url = {https://m2.mtmt.hu/api/publication/35742522}, author = {Hencz, Mátyás and Németh, Károly and Spránitz, Tamás and Biró, Tamás and Karátson, Dávid and Berkesi, Márta}, booktitle = {14. Kőzettani és Geokémiai Vándorgyűlés absztrakt kötet}, unique-id = {35742522}, year = {2024}, pages = {49-49}, orcid-numbers = {Hencz, Mátyás/0000-0001-9716-5714; Spránitz, Tamás/0000-0002-5086-3133; Biró, Tamás/0000-0001-5198-7210; Karátson, Dávid/0000-0003-0386-1239; Berkesi, Márta/0000-0003-4380-057X} } @CONFERENCE{MTMT:35740140, title = {Evolution of a maar-diatreme volcano within a sedimentary basin characterized by combined aquifer system}, url = {https://m2.mtmt.hu/api/publication/35740140}, author = {Hencz, Mátyás and Németh, Károly and Spránitz, Tamás and Biró, Tamás and Karátson, Dávid and Berkesi, Márta}, booktitle = {Krzywiec P et al. Book of Abstracts, 18th Workshop of the International Lithosphere Program Task Force Sedimentary Basins 07–11 october 2024 Kraków, Poland. (2024)}, unique-id = {35740140}, year = {2024}, pages = {30-30}, orcid-numbers = {Hencz, Mátyás/0000-0001-9716-5714; Spránitz, Tamás/0000-0002-5086-3133; Biró, Tamás/0000-0001-5198-7210; Karátson, Dávid/0000-0003-0386-1239; Berkesi, Márta/0000-0003-4380-057X} } @CONFERENCE{MTMT:35723844, title = {Comparison of quantitative and qualitative-quantitative geodiversity assessment-based geosite recognition in the Novohrad-Nógrád UNESCO Global Geopark, Hungary/Slovakia}, url = {https://m2.mtmt.hu/api/publication/35723844}, author = {Vladyslav, Zakharovskyi and Pál, Márton and Németh, Károly}, booktitle = {EGU General Assembly 2024}, doi = {10.5194/egusphere-egu24-353, 2024}, unique-id = {35723844}, year = {2024}, pages = {1}, orcid-numbers = {Pál, Márton/0000-0001-6321-7803} } @article{MTMT:35469284, title = {Reappraising the eruptive history of the Alchichica Maar Volcano (Mexico) based on Sr–Nd isotopes: Understanding the role of the magma source region on the growth of small-volume volcanoes}, url = {https://m2.mtmt.hu/api/publication/35469284}, author = {Chako-Tchamabé, Boris and Weber, Bodo and Gountié, Dedzo Merlin and Tamen, Jules and Silis-Esquivel, Jhoanna and Németh, Károly}, doi = {10.1016/j.sesci.2024.100214}, journal-iso = {SOLID EARTH SCIENCES}, journal = {SOLID EARTH SCIENCES}, volume = {9}, unique-id = {35469284}, issn = {2451-912X}, abstract = {Alchichica Maar is in the eastern sector of the Trans-Mexican Volcanic Belt, where volcanics range from basalts to rhyolites, with 87Sr/86Sr and 143Nd/144Nd values between 0.70293 to 0.70447 (εSr = −21.1 to −4.5) and 0.512733 to 0.512949 (εNd = +3.4 to +6.2), respectively. In this study, Nd and Sr isotopic data and new major and trace elements compositions are provided for the lava flow, the scoria cone, and the phreatomagmatic deposits composing Alchichica Maar Volcano. These results are used in combination with published data to reexamine its eruptive history, though to be formed by more than one eruptive event. The cogeneticy of the magmas that fed the eruptions of these deposits is examined to infer the role of the deep magma source region and post-magmatic alterations on the construction of the Alchichica Maar magmatic system. Alchichica samples present 87Sr/86Sr values between 0.70387 and 0.70447 (εSr = −9.0 to −0.4) and 143Nd/144Nd values from 0.512749 to 0.512773 (εNd = +2.0 to +2.8). While the 87Sr/86Sr values suggest a slight increment in radiogenic 87Sr from the pre-maar lower lava flow to the upper maar eruptions indicative of magma contamination within the upper crust and by hydrodynamic mingling during the phreatomagmatic phases, the slight variation in Nd isotopes suggest an overall homogeneous source where small batches of magmas formed episodically to feed monogenetic eruptions, which subsequently yielded the pre-maar lava flow, the pre-maar surge, the scoria cone, and the maar units. This study reinforces the idea that an already “tapped” source region of a monogenetic volcano may become fertile again, and new eruptions can occur from near or old vent sites. It also highlights the hazardous potential of small-volume volcanoes.}, keywords = {Alchichica maar; Magma source; small-volume volcanoes; cogenetic; Eruptive episodes; Hydrodynamic mingling}, year = {2024}, eissn = {2451-912X}, pages = {100214} } @CONFERENCE{MTMT:35201461, title = {Origin and Evolution of the Middle Atlas Volcanic Field (Morocco) A Volcanological, Petrological, Mineralogical and Geochemical Perspective}, url = {https://m2.mtmt.hu/api/publication/35201461}, author = {Mohammed, Benamrane and José, Francisco Santos and João, Mata and El, Hassan Talbi and Németh, Károly and Luís, Portela}, booktitle = {Origin and Evolution of the Middle Atlas Volcanic Field (Morocco) A Volcanological, Petrological, Mineralogical and Geochemical Perspective}, unique-id = {35201461}, year = {2024}, pages = {10} } @misc{MTMT:35201459, title = {Origin and Evolution of the Middle Atlas Volcanic Field (Morocco) A Volcanological, Petrological, Mineralogical and Geochemical Perspective}, url = {https://m2.mtmt.hu/api/publication/35201459}, author = {Mohammed, Benamrane and José, Francisco Santos and João, Mata and El, Hassan Talbi and Németh, Károly and Luís, Portela}, unique-id = {35201459}, year = {2024} } @misc{MTMT:35201455, title = {Origin and Evolution of the Middle Atlas Volcanic Field (Morocco) A Volcanological, Petrological, Mineralogical and Geochemical Perspective}, url = {https://m2.mtmt.hu/api/publication/35201455}, author = {Mohammed, Benamrane and José, Francisco Santos and João, Mata and El, Hassan Talbi and Németh, Károly and Luís, Portela}, unique-id = {35201455}, year = {2024} } @article{MTMT:35164900, title = {Evolution and polycyclic nature of a maar-diatreme volcano as constrained by changing external factors}, url = {https://m2.mtmt.hu/api/publication/35164900}, author = {Hencz, Mátyás and Németh, Károly and Spránitz, Tamás and Biró, Tamás and Karátson, Dávid and Berkesi, Márta}, doi = {10.1016/j.jvolgeores.2024.108158}, journal-iso = {J VOLCANOL GEOTH RES}, journal = {JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH}, volume = {453}, unique-id = {35164900}, issn = {0377-0273}, year = {2024}, eissn = {1872-6097}, orcid-numbers = {Hencz, Mátyás/0000-0001-9716-5714; Spránitz, Tamás/0000-0002-5086-3133; Karátson, Dávid/0000-0003-0386-1239; Berkesi, Márta/0000-0003-4380-057X} } @inbook{MTMT:35139063, title = {Synthesis}, url = {https://m2.mtmt.hu/api/publication/35139063}, author = {Németh, Károly and Moufti, Mohammed Rashad H.}, booktitle = {Geoheritage and Geodiversity of Cenozoic Volcanic Fields in Saudi Arabia}, doi = {10.1007/978-3-031-61217-6_7}, unique-id = {35139063}, abstract = {In this book we provided a detailed summary of the geoheritage aspects of the dispersed Cenozoic (mostly Neogene–Quaternary) volcanic fields of western Saudi Arabia.}, year = {2024}, pages = {181-184} }