The Cenozoic Gharyan volcanic province (GVP) represents one of the four major igneous districts of Libya, spreading over an area of ~4,500 km2. Despite the location of GVP close to major population centres in northwest Tripoli, the number of studies on the origin of this magmatism is relatively limited. Here, we discuss whole-rock geochemical data and present a new mineral chemistry and a 40Ar/39Ar geochronology study of the basaltic rocks of GVP. The mineralogical and geochemical differences of the two types of basalts identified in literature, definedas “plateau” and “late” basalts cannot be related to fractional crystallisation of a common parent magma. The two groups of basaltic rocks are better interpreted as liquids generated from the same mantle source experiencing different degrees of partial melting, with the late-stage basalts representing lower degrees of melt extraction, without indication of crustal contamination. Trace element constraints support an origin from~2 to ~12% partial melting of a heterogeneous sub-lithospheric mantle close to the spinel-garnet transition at ~70-90 km depth.Trace elements and Sr-Nd isotopic compositions of the Gharyan basaltic rocks overlap the other Cenozoic volcanic rocks of central Libya (e.g., Al Haruj volcanic province) and southern Italy (e.g., Etna and Pantelleria), lacking the presence of the enriched mantle component identified in other North African Cenozoic basaltic provinces. The new high precision 40Ar/39Ar age determinations indicate roughly simultaneous eruption ages of the two basaltic lava series, mostly in the 5.4-3.8 Ma range, with plateau basalts being statistically slightly older than the late stage, but with a large overlap. The dating of a dyke to ~28 Ma indicates the presence of an older Oligocene volcanic phase, whose products have been almost entirely eroded. The youngest age reported in this study indicates that volcanic activity continued until latest Pliocene (2.67 Ma). The overlap of 40Ar/39Ar ages between “plateau” and“late” basalts indicates that the existence of two distinct volcanic phases should be reconsidered.
{"title":"Geochemistry and 40Ar/39Ar ages of late Cenozoic basaltic rocks from Gharyan Volcanic Province, NW Libya","authors":"Abdelmoniem Masoud, Abdelsalam Elshaafi, Özgür Karaoğlu, Alsedik Abousif, Michele Lustrino","doi":"10.3301/ijg.2023.24","DOIUrl":"https://doi.org/10.3301/ijg.2023.24","url":null,"abstract":"The Cenozoic Gharyan volcanic province (GVP) represents one of the four major igneous districts of Libya, spreading over an area of ~4,500 km2. Despite the location of GVP close to major population centres in northwest Tripoli, the number of studies on the origin of this magmatism is relatively limited. Here, we discuss whole-rock geochemical data and present a new mineral chemistry and a 40Ar/39Ar geochronology study of the basaltic rocks of GVP. The mineralogical and geochemical differences of the two types of basalts identified in literature, definedas “plateau” and “late” basalts cannot be related to fractional crystallisation of a common parent magma. The two groups of basaltic rocks are better interpreted as liquids generated from the same mantle source experiencing different degrees of partial melting, with the late-stage basalts representing lower degrees of melt extraction, without indication of crustal contamination. Trace element constraints support an origin from~2 to ~12% partial melting of a heterogeneous sub-lithospheric mantle close to the spinel-garnet transition at ~70-90 km depth.Trace elements and Sr-Nd isotopic compositions of the Gharyan basaltic rocks overlap the other Cenozoic volcanic rocks of central Libya (e.g., Al Haruj volcanic province) and southern Italy (e.g., Etna and Pantelleria), lacking the presence of the enriched mantle component identified in other North African Cenozoic basaltic provinces. The new high precision 40Ar/39Ar age determinations indicate roughly simultaneous eruption ages of the two basaltic lava series, mostly in the 5.4-3.8 Ma range, with plateau basalts being statistically slightly older than the late stage, but with a large overlap. The dating of a dyke to ~28 Ma indicates the presence of an older Oligocene volcanic phase, whose products have been almost entirely eroded. The youngest age reported in this study indicates that volcanic activity continued until latest Pliocene (2.67 Ma). The overlap of 40Ar/39Ar ages between “plateau” and“late” basalts indicates that the existence of two distinct volcanic phases should be reconsidered.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135274816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Diego Pieruccioni, Amalia Spina, Andrea Brogi, Enrico Capezzuoli, Martina Zucchi, Simone Vezzoni, Domenico Liotta, Andrea Sorci, Giancarlo Molli
This study aims at refining the geological setting of the Fornovolasco area in the southern part of the Alpi Apuane (Northern Apennines, Italy). Due to the occurrence of Palaeozoic units of debated origin and age, its structural setting is the key for the comprehension of the evolution of the easternmost sector of the Alpi Apuane. In this context, we combined a 1:5,000 scale field survey with microfloristic and organic matter study, and petrographical and structural analysis. By means of this approach, we obtained the following results: (a) the “Fornovolasco schists” consists of two different lithostratigraphic units: (i) quartz-metasandstone with interbedded levels of graphitic metapelite, characterized by upper Cambrian (Miaolingian-Furongian) acritarch microflora and relatable to the Filladi inferiori Fm; (ii) graphitic metapelite, fine-grained metasandstone and metabreccia, with a well-preservedand diversified middle-upper Permian sporomorphs microflora, making it possible to correlate this unit with the Montignoso Formation. This evidence documents, for the first time, the occurrence of a post-Variscan Palaeozoic unit in the eastern Alpi Apuane.(b) The “Fornovolasco schists” hosts centimetre-thick tourmaline veins and a diffuse network of felsic sheet-like dyke plutonic bodies, supporting widespread magma intrusion associated with hydrothermal activities framed in the post-Variscan magmatism.(c) The studied area consists of three stacked first-order tectonic units: the Tuscan Nappe, Panie Unit, and Apuane Unit. These are characterized by superposed deformational structures of which development was assisted by low-to very-low-grade metamorphism developed during underplating and subsequent exhumation events.
{"title":"The Fornovolasco area (Alpi Apuane, Northern Apennines): a review and update on its Palaeozoic succession, middle Permian magmatism, and tectonic setting","authors":"Diego Pieruccioni, Amalia Spina, Andrea Brogi, Enrico Capezzuoli, Martina Zucchi, Simone Vezzoni, Domenico Liotta, Andrea Sorci, Giancarlo Molli","doi":"10.3301/ijg.2023.25","DOIUrl":"https://doi.org/10.3301/ijg.2023.25","url":null,"abstract":"This study aims at refining the geological setting of the Fornovolasco area in the southern part of the Alpi Apuane (Northern Apennines, Italy). Due to the occurrence of Palaeozoic units of debated origin and age, its structural setting is the key for the comprehension of the evolution of the easternmost sector of the Alpi Apuane. In this context, we combined a 1:5,000 scale field survey with microfloristic and organic matter study, and petrographical and structural analysis. By means of this approach, we obtained the following results: (a) the “Fornovolasco schists” consists of two different lithostratigraphic units: (i) quartz-metasandstone with interbedded levels of graphitic metapelite, characterized by upper Cambrian (Miaolingian-Furongian) acritarch microflora and relatable to the Filladi inferiori Fm; (ii) graphitic metapelite, fine-grained metasandstone and metabreccia, with a well-preservedand diversified middle-upper Permian sporomorphs microflora, making it possible to correlate this unit with the Montignoso Formation. This evidence documents, for the first time, the occurrence of a post-Variscan Palaeozoic unit in the eastern Alpi Apuane.(b) The “Fornovolasco schists” hosts centimetre-thick tourmaline veins and a diffuse network of felsic sheet-like dyke plutonic bodies, supporting widespread magma intrusion associated with hydrothermal activities framed in the post-Variscan magmatism.(c) The studied area consists of three stacked first-order tectonic units: the Tuscan Nappe, Panie Unit, and Apuane Unit. These are characterized by superposed deformational structures of which development was assisted by low-to very-low-grade metamorphism developed during underplating and subsequent exhumation events.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135324333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A new section of Upper Pleistocene alluvial-colluvial deposits in the foothills of the Marche Ridge (Apennine Mountains of central Italy)","authors":"A. Montanari, Gaia Pignocchi","doi":"10.3301/ijg.2023.21","DOIUrl":"https://doi.org/10.3301/ijg.2023.21","url":null,"abstract":"","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48061306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pietro Bazzicalupo, G. Bosio, A. Meroni, Giulia Piazza, A. Varzi, L. Fallati, G. Coletti, L. Mariani, M. Borgnino, Fabien Desbiolles, L. Borromeo
{"title":"The precarious life of Early Career Geoscientists: data and perspectives from the Italian Academia","authors":"Pietro Bazzicalupo, G. Bosio, A. Meroni, Giulia Piazza, A. Varzi, L. Fallati, G. Coletti, L. Mariani, M. Borgnino, Fabien Desbiolles, L. Borromeo","doi":"10.3301/ijg.2023.23","DOIUrl":"https://doi.org/10.3301/ijg.2023.23","url":null,"abstract":"","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43705509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Brogi, Lianchao Luo, Lorenzo Fabbrini, G. Pagano, P. Tuccimei, M. Soligo, E. Capezzuoli
{"title":"Tectonic control of thermal springs, gas vents and travertine deposition in Bagni di San Filippo and Campiglia d’Orcia area (Monte Amiata Volcano-Geothermal area, Italy)","authors":"A. Brogi, Lianchao Luo, Lorenzo Fabbrini, G. Pagano, P. Tuccimei, M. Soligo, E. Capezzuoli","doi":"10.3301/ijg.2023.17","DOIUrl":"https://doi.org/10.3301/ijg.2023.17","url":null,"abstract":"","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42892137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Mattei, Veronica Fioramonti, G. Cavinato, F. Cifelli, I. Mazzini, M. Parotto, R. Sardella, M. Sirna
{"title":"Magnetostratigraphy of the Collepardo late Pliocene faunal assemblage (Early Villafranchian Triversa Faunal Unit), Ernici Mts., Central Italy","authors":"M. Mattei, Veronica Fioramonti, G. Cavinato, F. Cifelli, I. Mazzini, M. Parotto, R. Sardella, M. Sirna","doi":"10.3301/ijg.2023.19","DOIUrl":"https://doi.org/10.3301/ijg.2023.19","url":null,"abstract":"","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47280100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Basilici, Matteo Pedini, Alessandro Spinaci, L. Del Sole, D. Jablonská, F. Capotorti, S. Mazzoli, P. Pierantoni
{"title":"Geological map, balanced and restored cross-sections, and 3D geological model of the Monte Fema area, Umbria-Marche Apennines (Italy)","authors":"M. Basilici, Matteo Pedini, Alessandro Spinaci, L. Del Sole, D. Jablonská, F. Capotorti, S. Mazzoli, P. Pierantoni","doi":"10.3301/ijg.2023.22","DOIUrl":"https://doi.org/10.3301/ijg.2023.22","url":null,"abstract":"","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45520616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Palano, A. Billi, A. Conti, M. Cuffaro, B. Orecchio, D. Presti, S. Scolaro, F. Sparacino, C. Totaro
{"title":"The intra-orogenic normal Lakes Fault (Sila, Calabria, southern Italy): new insights from geodetic and seismological data","authors":"M. Palano, A. Billi, A. Conti, M. Cuffaro, B. Orecchio, D. Presti, S. Scolaro, F. Sparacino, C. Totaro","doi":"10.3301/ijg.2023.18","DOIUrl":"https://doi.org/10.3301/ijg.2023.18","url":null,"abstract":"","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47616412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohamed Belkercha, Fadila Yacef, B. Ferré, M. Bendella, M. Bensalah, L. Villier, M. Zaagane
{"title":"Redescription of Schizobrissus mauritanicus Pomel, 1885, on the basis of new topotypic material from the Lower Miocene of the Oran region (northwestern Algeria)","authors":"Mohamed Belkercha, Fadila Yacef, B. Ferré, M. Bendella, M. Bensalah, L. Villier, M. Zaagane","doi":"10.3301/ijg.2023.20","DOIUrl":"https://doi.org/10.3301/ijg.2023.20","url":null,"abstract":"","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48147069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Felicita Spreafico, S. Basiricò, A. Previati, P. Frattini, G. Crosta
{"title":"Characterization of the Grigna karst aquifer (Northern Italy) by springs monitoring and tracer tests","authors":"Felicita Spreafico, S. Basiricò, A. Previati, P. Frattini, G. Crosta","doi":"10.3301/ijg.2023.11","DOIUrl":"https://doi.org/10.3301/ijg.2023.11","url":null,"abstract":"","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41438709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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