L. Bellucci, I. Biddittu, M. Brilli, J. Conti, M. Germani, F. Giustini, D. A. Iurino, I. Mazzini, R. Sardella
This research received support from the SYNTHESYS Project ES-TAF-5621 http://www.synthesys.info/ which is financed by European Community Research Infrastructure Action under the FP7 «Capacities» Programme at Museo Nacional de Ciencias Naturales (CSIC) and from “Ricerche di Ateneo 2015” (Sapienza University of Rome, resp. Raffaele Sardella).
这项研究得到了synthesis项目ES-TAF-5621 http://www.synthesys.info/的支持，该项目由欧洲共同体研究基础设施行动在国家自然科学博物馆(CSIC) FP7“能力”计划下资助，并从“Ricerche di Ateneo 2015”(罗马Sapienza大学，resp.)获得资助。拉斐尔Sardella)。
{"title":"First occurrence of the short-faced bear Agriotherium (Ursidae, Carnivora) in Italy: biochronological and palaeoenvironmental implications","authors":"L. Bellucci, I. Biddittu, M. Brilli, J. Conti, M. Germani, F. Giustini, D. A. Iurino, I. Mazzini, R. Sardella","doi":"10.3301/IJG.2018.31","DOIUrl":"https://doi.org/10.3301/IJG.2018.31","url":null,"abstract":"This research \u0000received support from the SYNTHESYS Project ES-TAF-5621 \u0000http://www.synthesys.info/ which is financed by European Community \u0000Research Infrastructure Action under the FP7 «Capacities» \u0000Programme at Museo Nacional de Ciencias Naturales (CSIC) and \u0000from “Ricerche di Ateneo 2015” (Sapienza University of Rome, resp. \u0000Raffaele Sardella).","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2018.31","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42306773","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}
This work describes and analyses the December 2004 rockslide that affected the working face of the Ca’ Madonna quarry (Municipality of Urbania, Province of Pesaro and Urbino, Italy), where limestones are extensively quarried for aggregates. The landslide occurred along an unsurveyed, approximately 10-cm thick clayey intra-bed layer that mainly consists of smectite-group clayey minerals. Laboratory analyses indicate that it is very active and shows a high capacity to absorb water until reaching a swelling pressure of up to 1200 kPa. Mining activities reduced lithostatic load and facilitated rainwater infiltration down to this bentonitic layer, which led to fully softened conditions with a resulting severe reduction in the shear strength parameters. Under such conditions, the slope stability back-analysis was performed by the limit equilibrium method, considering a planar rock slope failure with tension cracks and with different water level heights. The results show that a small increase of water pressure was sufficient to exceed the factor of safety. Stratigraphically, this layer can be correlated with the Lower Campanian Bentonitic Layer already reported in other sites of Central Italy. Therefore, the potentially great spatial extent of this layer and the possibility that the reported conditions may occur in other similar settings, make it important to identify its presence in order to prevent analogous situations.
{"title":"The role of a bentonitic layer on slope stability in bedded limestone: the case study of the December 2004 Ca' Madonna Quarry rock slide (Umbria-Marche Apennines, Central Italy)","authors":"G. Tonelli, F. Veneri, M. Mattioli, C. Paletta","doi":"10.3301/IJG.2018.26","DOIUrl":"https://doi.org/10.3301/IJG.2018.26","url":null,"abstract":"This work describes and analyses the December 2004 rockslide that affected the working face of the Ca’ Madonna quarry (Municipality of Urbania, Province of Pesaro and Urbino, Italy), where limestones are extensively quarried for aggregates. The landslide occurred along an unsurveyed, approximately 10-cm thick clayey intra-bed layer that mainly consists of smectite-group clayey minerals. Laboratory analyses indicate that it is very active and shows a high capacity to absorb water until reaching a swelling pressure of up to 1200 kPa. Mining activities reduced lithostatic load and facilitated rainwater infiltration down to this bentonitic layer, which led to fully softened conditions with a resulting severe reduction in the shear strength parameters. Under such conditions, the slope stability back-analysis was performed by the limit equilibrium method, considering a planar rock slope failure with tension cracks and with different water level heights. The results show that a small increase of water pressure was sufficient to exceed the factor of safety. Stratigraphically, this layer can be correlated with the Lower Campanian Bentonitic Layer already reported in other sites of Central Italy. Therefore, the potentially great spatial extent of this layer and the possibility that the reported conditions may occur in other similar settings, make it important to identify its presence in order to prevent analogous situations.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49533379","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}
The shallowest part (about 3 sec two-way traveltime) of theCROP line M-2A/I, acquired during 1991 in the Bonifacio Strait(between Corsica and Sardinia), has been reprocessed to improveits geological interpretation. The original target of the M-2A/I profilewas the entire crust and therefore the shallowest part was onlypartially interpreted. In this context, the re-processing procedure wascarried out to improve the signal-to-noise ratio and the resolutionof the M-2A/I seismic profile at shallow depth. The geologicalinterpretation of the reprocessed data aimed at the reconstructionof the sedimentary succession and the contact with the underlyingHercynian basement.The M-2A/I seismic profile has been interpreted identifyingdiverse seismic facies, interpreted considering the geological unitsoutcropping to the north (in Corsica) and to the south (in Sardinia)of the seismic profile. The study supports the existence of a thickMesozoic succession, onlapping the Hercynian basement, preservedbelow the Cenozoic succession in the Asinara Gulf, suggesting that theNurra succession continues northward below the sea. The Mesozoic succession is bordered by a major, east-dipping normal fault, east the Asinara Island ridge. The faults recognized in the seismic profile indicate a prevailing strike slip/transtensional tectonics, questioning the role of compressional tectonics suggested in a previousinterpretation. The obtained results also indicate the potential of reprocessing of existing seismic profiles, whose interpretation can be significantly updated thanks to the development of new processing procedures and to the continuous upgrade of the regional geological knowledge.
{"title":"New information from 'old' seismic lines: an updated geological interpretation from the re-processing of the CROP line M-2A/I (Bonifacio Straits) at shallow depths","authors":"F. Berra, E. Stucchi, S. Moretti","doi":"10.3301/IJG.2018.24","DOIUrl":"https://doi.org/10.3301/IJG.2018.24","url":null,"abstract":"The shallowest part (about 3 sec two-way traveltime) of theCROP line M-2A/I, acquired during 1991 in the Bonifacio Strait(between Corsica and Sardinia), has been reprocessed to improveits geological interpretation. The original target of the M-2A/I profilewas the entire crust and therefore the shallowest part was onlypartially interpreted. In this context, the re-processing procedure wascarried out to improve the signal-to-noise ratio and the resolutionof the M-2A/I seismic profile at shallow depth. The geologicalinterpretation of the reprocessed data aimed at the reconstructionof the sedimentary succession and the contact with the underlyingHercynian basement.The M-2A/I seismic profile has been interpreted identifyingdiverse seismic facies, interpreted considering the geological unitsoutcropping to the north (in Corsica) and to the south (in Sardinia)of the seismic profile. The study supports the existence of a thickMesozoic succession, onlapping the Hercynian basement, preservedbelow the Cenozoic succession in the Asinara Gulf, suggesting that theNurra succession continues northward below the sea. The Mesozoic succession is bordered by a major, east-dipping normal fault, east the Asinara Island ridge. The faults recognized in the seismic profile indicate a prevailing strike slip/transtensional tectonics, questioning the role of compressional tectonics suggested in a previousinterpretation. The obtained results also indicate the potential of reprocessing of existing seismic profiles, whose interpretation can be significantly updated thanks to the development of new processing procedures and to the continuous upgrade of the regional geological knowledge.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41825931","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}
The aim of this paper is to show how the classical methods of geology can be used to evaluate local seismic effects. This knowledge is essential for planning the renovation of public and private buildings and preserving architectural heritage. The urban area of Benevento, located in the Sannio Region, on the axis of the Southern Apennine Chain, is the case in point. A detailed geological survey was carried out. Sixteen boreholes were analysed, and 400 stratigraphic logs were re-interpreted. According to the sediment characteristics, and depositional environments, several stratigraphic units were recognized. Their stratal correlation patterns enabled the creation of a geological model. The bed-rock consists of Meso-Cenozoic pre- andsyn-orogenic units followed by cover units, the oldest of which consists of lower Pleistocene Pacevecchia alluvial deposits. A geological map (1:4.000 scale), and five cross-sections define the geological model of reference. The possible amplification of seismic waves was assessed on the basis of the stratigraphic units and their internal and external characteristics in terms of lithology, lateral and vertical variations, thickness, and heterogeneity. Therefore, areas of the city safe or withthe possibility to be affected by amplification phenomena have been defined. These geological results are supported by geophysical data.
{"title":"The Quaternary geology of the Benevento urban area (southern Italy) for seismic microzonation purposes","authors":"M. Senatore, M. Boscaino, Felice Pinto","doi":"10.3301/IJG.2018.27","DOIUrl":"https://doi.org/10.3301/IJG.2018.27","url":null,"abstract":"The aim of this paper is to show how the classical methods of geology can be used to evaluate local seismic effects. This knowledge is essential for planning the renovation of public and private buildings and preserving architectural heritage. The urban area of Benevento, located in the Sannio Region, on the axis of the Southern Apennine Chain, is the case in point. A detailed geological survey was carried out. Sixteen boreholes were analysed, and 400 stratigraphic logs were re-interpreted. According to the sediment characteristics, and depositional environments, several stratigraphic units were recognized. Their stratal correlation patterns enabled the creation of a geological model. The bed-rock consists of Meso-Cenozoic pre- andsyn-orogenic units followed by cover units, the oldest of which consists of lower Pleistocene Pacevecchia alluvial deposits. A geological map (1:4.000 scale), and five cross-sections define the geological model of reference. The possible amplification of seismic waves was assessed on the basis of the stratigraphic units and their internal and external characteristics in terms of lithology, lateral and vertical variations, thickness, and heterogeneity. Therefore, areas of the city safe or withthe possibility to be affected by amplification phenomena have been defined. These geological results are supported by geophysical data.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2018.27","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69480273","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}
Luca Samperi, K. Omosanya, G. Minelli, S. Johansen
The Veslemoy High is located in the southwestern sector of the Barents Sea and its geological evolution is strictly linked to the geodynamic development of the Norwegian region. The tectonic evolution of the Veslemoy High and several other structural elements of the Barents Sea remains poorly understood mostly because of a general lack of stratigraphic control, high-quality data and the complex interplay of geodynamic episodes, which has prevented the structures and ages of several stratigraphic units to be correctly constrained.This study used 3-D and 2-D seismic reflection data, integrated with well data to reconstruct the geological history of the Veslemoy High area. The methods here used include seismic interpretation of several horizons and faults, seismic-well data calibration (well 7219/8-1S) and well data (7216/11-1S; 7218/11-1; 7218/8-1; 7219/8-1S). Such an investigation led to the definition of several compressional andextensional tectonic phases, which affected the area most especially in pre-Cenozoic time. The oldest compressional phase here documented is Late Cretaceous and is marked by large-scale anticlines and synclines (about 10 km wavelength). Following this tectonic phase, the study area was affected by a system of mainly west dipping normal faults, creating several half graben structures. In some cases, these grabens display evidences of slight positive inversion. Analysis of the Late Cretaceous sequence provides interesting markers of sediments infilling patterns, erosional surfaces, uplift, tilting, faulting, extensional and contractional structures. All these structures point to a complex interplay of Pre-, Syn- and Post-Late Cretaceous tectonic activities. Importantly, the Lower Regional Unconformity (LRU), Upper Regional Unconformity (URU), stratigraphic terminations, and faults are significant tectonic markers in the Veslemoy High area and in surrounding basins. Tectonic structures documented here are characteristics of the Mesozoic and Cenozoic geological framework of the NE Atlantic margin.
{"title":"Tectono-stratigraphic evolution of Late Cretaceous basins into Veslemøy High, SW Barents Sea","authors":"Luca Samperi, K. Omosanya, G. Minelli, S. Johansen","doi":"10.3301/IJG.2018.23","DOIUrl":"https://doi.org/10.3301/IJG.2018.23","url":null,"abstract":"The Veslemoy High is located in the southwestern sector of the Barents Sea and its geological evolution is strictly linked to the geodynamic development of the Norwegian region. The tectonic evolution of the Veslemoy High and several other structural elements of the Barents Sea remains poorly understood mostly because of a general lack of stratigraphic control, high-quality data and the complex interplay of geodynamic episodes, which has prevented the structures and ages of several stratigraphic units to be correctly constrained.This study used 3-D and 2-D seismic reflection data, integrated with well data to reconstruct the geological history of the Veslemoy High area. The methods here used include seismic interpretation of several horizons and faults, seismic-well data calibration (well 7219/8-1S) and well data (7216/11-1S; 7218/11-1; 7218/8-1; 7219/8-1S). Such an investigation led to the definition of several compressional andextensional tectonic phases, which affected the area most especially in pre-Cenozoic time. The oldest compressional phase here documented is Late Cretaceous and is marked by large-scale anticlines and synclines (about 10 km wavelength). Following this tectonic phase, the study area was affected by a system of mainly west dipping normal faults, creating several half graben structures. In some cases, these grabens display evidences of slight positive inversion. Analysis of the Late Cretaceous sequence provides interesting markers of sediments infilling patterns, erosional surfaces, uplift, tilting, faulting, extensional and contractional structures. All these structures point to a complex interplay of Pre-, Syn- and Post-Late Cretaceous tectonic activities. Importantly, the Lower Regional Unconformity (LRU), Upper Regional Unconformity (URU), stratigraphic terminations, and faults are significant tectonic markers in the Veslemoy High area and in surrounding basins. Tectonic structures documented here are characteristics of the Mesozoic and Cenozoic geological framework of the NE Atlantic margin.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48850706","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}
C. Rispoli, L. Fedele, C. D. Benedetto, Renata Esposito, S. F. Graziano, V. Guarino, V. Morra, P. Cappelletti
This work is the result of a geoarchaeological investigation on the Anfiteatro Flavio, one of the most important archaeological sites in the Campania region (southern Italy), situated in an area of great geological and archaeological interest, the Campi Flegrei volcanic field. The aim of this research was to characterise building stonesemployed for structural use, focusing on the type of materials and their provenance. The mineralogical-petrographic characterization of 27 samples from corbels and pillars involved X-ray powder diffraction analyses (XRPD), thin section optical microscopy observations (OM) and energy dispersive spectrometry microanalyses (EDS). The results revealed that the source materials are represented by two distinctive trachytic/phonolitic lava deposits. Pillar light grey block samplesare made of a feldspar-phyric (F-p) lava type that shares many petrographic and mineral chemical features with the Campi Flegrei Accademia lava dome, cropping out in the immediate proximities of the Anfiteatro Flavio. On the other hand, pillar grey block and corbel samples are made of an alkali feldspar and sodalite-phyric (KS-p) lava that has been correlated to an Ischian lava deposit based mainly of the peculiar composition of the observed amphibole crystals. Previous data attesting for the use of the Piperno welded tuff for the pillar grey blocks were likely driven by the “eutaxitic-like” fluidal oriented texture and by the alveolitization alteration displayed by the samples. This however does not exclude that the Piperno had been employed as a building stone for other structural elements of the amphitheatre. The use of the Ischia lavas as an exported building material had been never reported before, possibly suggesting that current knowledges about the use and trade of building materials in the Campania area during the Roman period need to be reconsidered.
{"title":"Characterization of building materials from the Anfiteatro Flavio (Pozzuoli, southern Italy): a mineralogical and petrographic study","authors":"C. Rispoli, L. Fedele, C. D. Benedetto, Renata Esposito, S. F. Graziano, V. Guarino, V. Morra, P. Cappelletti","doi":"10.3301/IJG.2018.29","DOIUrl":"https://doi.org/10.3301/IJG.2018.29","url":null,"abstract":"This work is the result of a geoarchaeological investigation on the Anfiteatro Flavio, one of the most important archaeological sites in the Campania region (southern Italy), situated in an area of great geological and archaeological interest, the Campi Flegrei volcanic field. The aim of this research was to characterise building stonesemployed for structural use, focusing on the type of materials and their provenance. The mineralogical-petrographic characterization of 27 samples from corbels and pillars involved X-ray powder diffraction analyses (XRPD), thin section optical microscopy observations (OM) and energy dispersive spectrometry microanalyses (EDS). The results revealed that the source materials are represented by two distinctive trachytic/phonolitic lava deposits. Pillar light grey block samplesare made of a feldspar-phyric (F-p) lava type that shares many petrographic and mineral chemical features with the Campi Flegrei Accademia lava dome, cropping out in the immediate proximities of the Anfiteatro Flavio. On the other hand, pillar grey block and corbel samples are made of an alkali feldspar and sodalite-phyric (KS-p) lava that has been correlated to an Ischian lava deposit based mainly of the peculiar composition of the observed amphibole crystals. Previous data attesting for the use of the Piperno welded tuff for the pillar grey blocks were likely driven by the “eutaxitic-like” fluidal oriented texture and by the alveolitization alteration displayed by the samples. This however does not exclude that the Piperno had been employed as a building stone for other structural elements of the amphitheatre. The use of the Ischia lavas as an exported building material had been never reported before, possibly suggesting that current knowledges about the use and trade of building materials in the Campania area during the Roman period need to be reconsidered.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43687839","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. Incarbona, E. Stefano, P. Maiorano, M. Marino, N. Pelosi
The Ceara Rise lies just beyond the edge of the Amazon River Fan and sediments from this site may record the complex interplay of different climatic systems and processes, including past changes in southern America monsoon activity, Intertropical Convergence Zone setting, different Atlantic Meridional Overturning Circulation (AMOC) strength and phytoplankton blooming triggered by AmazonRiver plumes. Here we investigate early Pleistocene calcareous nannoplankton at Ceara Rise, between about 1150 and 850 kiloyears ago. Our investigation shows abrupt variations in water column dynamics across glacial/interglacial cycles or, even better, linked with different AMOC modes. Dominant placoliths indicate a shallow nutricline that alternate with dominant Florisphaera profunda, pointing to a deep nutricline, respectively during a vigorous flow and slowdown/shutdown of AMOC. The southward displacement of the ITCZ, higher zonal trade wind intensity, more intense and prolonged North Brazilian Current retroflection and the arrival of the nutrientdepleted Glacial North Atlantic Intermediate Water possibly explain thermocline deepening and increased water column stratification during cold phases, with an Antarctic deep water signature on the Ceara Rise seafloor.
{"title":"The response of calcareous nannoplankton to sea surface variability at Ceara Rise during the early Pleistocene glacial-interglacial cycles","authors":"A. Incarbona, E. Stefano, P. Maiorano, M. Marino, N. Pelosi","doi":"10.3301/IJG.2018.22","DOIUrl":"https://doi.org/10.3301/IJG.2018.22","url":null,"abstract":"The Ceara Rise lies just beyond the edge of the Amazon River Fan and sediments from this site may record the complex interplay of different climatic systems and processes, including past changes in southern America monsoon activity, Intertropical Convergence Zone setting, different Atlantic Meridional Overturning Circulation (AMOC) strength and phytoplankton blooming triggered by AmazonRiver plumes. Here we investigate early Pleistocene calcareous nannoplankton at Ceara Rise, between about 1150 and 850 kiloyears ago. Our investigation shows abrupt variations in water column dynamics across glacial/interglacial cycles or, even better, linked with different AMOC modes. Dominant placoliths indicate a shallow nutricline that alternate with dominant Florisphaera profunda, pointing to a deep nutricline, respectively during a vigorous flow and slowdown/shutdown of AMOC. The southward displacement of the ITCZ, higher zonal trade wind intensity, more intense and prolonged North Brazilian Current retroflection and the arrival of the nutrientdepleted Glacial North Atlantic Intermediate Water possibly explain thermocline deepening and increased water column stratification during cold phases, with an Antarctic deep water signature on the Ceara Rise seafloor.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45097654","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}
G. Cruciani, D. Fancello, M. Franceschelli, G. Musumeci
The Mt. Filau orthogneiss is an Ordovician orthogneiss outcropping in the External zone of SW Sardinia chain. It consists of dark, biotite-rich facies, a leucocratic coarse-grained facies and a leucocratic fine-grained facies with igneous andalusite. Coarse- and fine-grained leucocratic orthogneiss have comparable major elementcontents, being slightly enriched in SiO2 and depleted in Fe2O3, MgO, TiO2 and CaO as compared to the biotite-bearing orthogneiss. Bt-bearing orthogneiss shows higher Sr and Ba concentrations than leucocratic ones, whereas Rb content is higher in leucocratic orthogneiss as compared to the Bt-bearing ones. Zr content shows a progressive decrease from biotite-bearing orthogneiss, coarse-grained leucocratic ones, to fine-grained orthogneiss. In the spider diagram the Mt. Filau orthogneiss shows the typical signature of calc-alkaline rocks, with negative anomalies of Ba, Nb, Sr and Ti, and positive anomalies in U, K. REE patterns of Bt-bearing and coarse-grained leucocratic orthogneisses are characterized by a moderate LREE fractionation, flat HREE and negative Eu anomaly. Fine-grained leucocratic orthogneiss shows flatter patterns, stronger Eu anomalies and slight HREE enrichment. The geochemical features suggest a clear evolution trend, from the less evolved Bt-bearing orthogneiss to the more differentiated fine-grained leucocratic orthogneisses which likely represent aplite bodies deriving from the most acidic residual melt. Selected trace and REE elements of Mt. Filau are compared with other Ordovician orthogneiss outcropping in the Axial zone of Sardinia Variscan belt. Besides, their geochemical features are also compared with metavolcanics of External and Nappe zone. The geochemical affinity of orthogneisses and metavolcanics from Variscan Sardinia, together with the geochronological data, allows to state a clear cogenetic relationship between the bodies belonging to the calc-alkaline Ordovician magmatic cycle. Our results suggest that the early Paleozoic basement of Sardinia might represents the witness of an early Paleozoic subduction-accretionary complex recording convergence along the N/NE Gondwana margin.
{"title":"Geochemistry of the Monte Filau orthogneiss (SW Sardinia, Italy): insight into the geodynamic setting of Ordovician felsic magmatism in the N/NE Gondwana margin","authors":"G. Cruciani, D. Fancello, M. Franceschelli, G. Musumeci","doi":"10.3301/IJG.2018.32","DOIUrl":"https://doi.org/10.3301/IJG.2018.32","url":null,"abstract":"The Mt. Filau orthogneiss is an Ordovician orthogneiss outcropping in the External zone of SW Sardinia chain. It consists of dark, biotite-rich facies, a leucocratic coarse-grained facies and a leucocratic fine-grained facies with igneous andalusite. Coarse- and fine-grained leucocratic orthogneiss have comparable major elementcontents, being slightly enriched in SiO2 and depleted in Fe2O3, MgO, TiO2 and CaO as compared to the biotite-bearing orthogneiss. Bt-bearing orthogneiss shows higher Sr and Ba concentrations than leucocratic ones, whereas Rb content is higher in leucocratic orthogneiss as compared to the Bt-bearing ones. Zr content shows a progressive decrease from biotite-bearing orthogneiss, coarse-grained leucocratic ones, to fine-grained orthogneiss. In the spider diagram the Mt. Filau orthogneiss shows the typical signature of calc-alkaline rocks, with negative anomalies of Ba, Nb, Sr and Ti, and positive anomalies in U, K. REE patterns of Bt-bearing and coarse-grained leucocratic orthogneisses are characterized by a moderate LREE fractionation, flat HREE and negative Eu anomaly. Fine-grained leucocratic orthogneiss shows flatter patterns, stronger Eu anomalies and slight HREE enrichment. The geochemical features suggest a clear evolution trend, from the less evolved Bt-bearing orthogneiss to the more differentiated fine-grained leucocratic orthogneisses which likely represent aplite bodies deriving from the most acidic residual melt. Selected trace and REE elements of Mt. Filau are compared with other Ordovician orthogneiss outcropping in the Axial zone of Sardinia Variscan belt. Besides, their geochemical features are also compared with metavolcanics of External and Nappe zone. The geochemical affinity of orthogneisses and metavolcanics from Variscan Sardinia, together with the geochronological data, allows to state a clear cogenetic relationship between the bodies belonging to the calc-alkaline Ordovician magmatic cycle. Our results suggest that the early Paleozoic basement of Sardinia might represents the witness of an early Paleozoic subduction-accretionary complex recording convergence along the N/NE Gondwana margin.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45048391","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}
Concentrations of dissolved As can be related either to natural processes or anthropogenic activities. The aim of this study was to distinguish natural processes from potential anthropogenic effects on As occurrence in landfill areas. The study area is located in Central Sardinia and is characterized by Upper Pleistocene and Holocene sediments (sand and gravel with silt-clay matrix and local occurrence of thin ochreous colour levels; marsh deposits rich in organic matter and vegetal residues). The study area hosts an exhausted landfill where construction and demolition debris were disposed.The mineralogical composition of solid materials was characterized by quartz, feldspars and clay minerals. Concentrations of As were within the ranges reported in sediments and soils, except one sample that showed 46 mg/kg As.The waters showed near-neutral pH, variable electric conductivity (
{"title":"Assessing arsenic sources in landfill areas: a case study in Sardinia","authors":"F. Frau, R. Cidu, M. Casu, Andrea Soriga","doi":"10.3301/IJG.2018.30","DOIUrl":"https://doi.org/10.3301/IJG.2018.30","url":null,"abstract":"Concentrations of dissolved As can be related either to natural processes or anthropogenic activities. The aim of this study was to distinguish natural processes from potential anthropogenic effects on As occurrence in landfill areas. The study area is located in Central Sardinia and is characterized by Upper Pleistocene and Holocene sediments (sand and gravel with silt-clay matrix and local occurrence of thin ochreous colour levels; marsh deposits rich in organic matter and vegetal residues). The study area hosts an exhausted landfill where construction and demolition debris were disposed.The mineralogical composition of solid materials was characterized by quartz, feldspars and clay minerals. Concentrations of As were within the ranges reported in sediments and soils, except one sample that showed 46 mg/kg As.The waters showed near-neutral pH, variable electric conductivity (","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2018.30","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48657996","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}
Since the early nineteenth century, the structural high of Mt. Nerone in the Umbria-Marche Sabina Domain (UMS – Central/Northern Apennines, Italy) attracted scholars from all over Europe due to the wealth of fossil fauna preserved in a stunningly well-exposed Mesozoic sedimentary succession. Several geopalaeontological studies were focused on the abundant and diverse invertebrate fauna, whereas contributions dealing with Mesozoic vertebrates were to date virtually lacking. Recently, the first material referable to hybodont sharks, consisting of an articulated crushing dentition, was described from the area and referred to Asteracanthus cf. A. magnus. In this contribution, we report the first evidence of ginglymodians actinopterygians from the Upper Jurassic of Mt. Nerone. The material is represented by seven highly tritorial isolated teeth collected from three classic fossiliferous localities of the area (i.e. Pian del Sasso, Fosso Pisciarello, I Ranchi). The general morphology of the material under study allow us to conservatively refer the teeth to the Neoginglymodi, a clade formed by Lepisosteiformes and Semionotiformes. The occurrence of durophagous organisms, to date represented by hybodont sharks and lepisosteiformes fishes, reveals interesting palaeoecological scenarios characterizing the pelagic carbonate platform-basin system of Mt. Nerone, which were most likely triggered by large-scale geodynamic processes. The complex submarine palaeotopography, inheritance of the Western Tethys Early Jurassic rifting, aroused the establishment of new infaunal and epifaunal communities opening up unexplored trophic niches for durophagous predators. The particular geodynamic setting of the UMS Domain, consisting of predominantly interconnected structural highs and lows, and the relative evolution of a diverse invertebrate fauna characterized by terebratulid, ostreids, limids, brachiopods, crustaceans, and gastropods, attracted both hybodontids anddurophagous ginglymodians in the Tethyan Realm, influencing their dispersal during the Late Jurassic.
自19世纪初以来，Umbria Marche Sabina地区（UMS–意大利亚平宁山脉中部/北部）的Nerone山构造高地吸引了来自欧洲各地的学者，因为在一个暴露得惊人的中生代沉积序列中保存了丰富的动物化石。一些地质地质学研究集中在丰富多样的无脊椎动物区系上，而迄今为止几乎缺乏对中生代脊椎动物的研究。最近，该地区描述了第一个与hybodont鲨鱼有关的材料，该材料由一个铰接的破碎齿列组成，并被称为Asteracantus cf.A.magnus。在这篇文章中，我们报道了Nerone山上侏罗纪中首次发现的金藻-放线菌的证据。该材料的代表是从该地区的三个典型化石产地（即Pian del Sasso、Fosso Pisciarello和i Ranchi）采集的七颗高度三角孤立的牙齿。所研究材料的一般形态使我们能够保守地将牙齿称为Neoginglymodi，这是一个由Lepisoteiformes和Seminotiformes形成的分支。迄今为止，以hybodont鲨鱼和lepisoteiformes鱼类为代表的硬食性生物的出现，揭示了Nerone山上层碳酸盐岩平台-盆地系统的有趣古生态场景，这些场景很可能是由大规模地球动力学过程引发的。复杂的海底古地形继承了西特提斯-早侏罗世裂谷作用，引发了新的海底和表动物群落的建立，为食肉动物开辟了未经探索的营养生态位。UMS域的特殊地球动力学环境，主要由相互连接的结构高点和低点组成，以及以圆尾类、鸵鸟类、泥足类、腕足类、甲壳类动物和腹足类为特征的各种无脊椎动物的相对进化，吸引了特提斯域的hybodontids和食豆性的格纹蝶，影响了它们在晚侏罗世的扩散。
{"title":"First remains of Lepisosteiformes actinopterygians from the Jurassic of Monte Nerone area (Umbria-Marche Apennine, Italy)","authors":"M. Romano, A. Cipriani, S. Fabbi, P. Citton","doi":"10.3301/IJG.2018.28","DOIUrl":"https://doi.org/10.3301/IJG.2018.28","url":null,"abstract":"Since the early nineteenth century, the structural high of Mt. Nerone in the Umbria-Marche Sabina Domain (UMS – Central/Northern Apennines, Italy) attracted scholars from all over Europe due to the wealth of fossil fauna preserved in a stunningly well-exposed Mesozoic sedimentary succession. Several geopalaeontological studies were focused on the abundant and diverse invertebrate fauna, whereas contributions dealing with Mesozoic vertebrates were to date virtually lacking. Recently, the first material referable to hybodont sharks, consisting of an articulated crushing dentition, was described from the area and referred to Asteracanthus cf. A. magnus. In this contribution, we report the first evidence of ginglymodians actinopterygians from the Upper Jurassic of Mt. Nerone. The material is represented by seven highly tritorial isolated teeth collected from three classic fossiliferous localities of the area (i.e. Pian del Sasso, Fosso Pisciarello, I Ranchi). The general morphology of the material under study allow us to conservatively refer the teeth to the Neoginglymodi, a clade formed by Lepisosteiformes and Semionotiformes. The occurrence of durophagous organisms, to date represented by hybodont sharks and lepisosteiformes fishes, reveals interesting palaeoecological scenarios characterizing the pelagic carbonate platform-basin system of Mt. Nerone, which were most likely triggered by large-scale geodynamic processes. The complex submarine palaeotopography, inheritance of the Western Tethys Early Jurassic rifting, aroused the establishment of new infaunal and epifaunal communities opening up unexplored trophic niches for durophagous predators. The particular geodynamic setting of the UMS Domain, consisting of predominantly interconnected structural highs and lows, and the relative evolution of a diverse invertebrate fauna characterized by terebratulid, ostreids, limids, brachiopods, crustaceans, and gastropods, attracted both hybodontids anddurophagous ginglymodians in the Tethyan Realm, influencing their dispersal during the Late Jurassic.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2018.28","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46147946","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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