Italian Journal of Geosciences最新文献

{"title":"U-Pb ages on detrital zircons and geochemistry of Lula paragneiss from Variscan belt, NE Sardinia, Italy: implications for source rocks and early Paleozoic paleogeography","authors":"G. Cruciani, M. Franceschelli, V. Caironi, G. Musumeci","doi":"10.3301/ijg.2019.24","DOIUrl":"https://doi.org/10.3301/ijg.2019.24","url":null,"abstract":"Chemical analyses of garnet-bearing metasediments and EMP and U/Pb analyses of detrital zircons of the Lula paragneisses in the Axial Zone of the Variscan belt (NE Sardinia) give significant contribution to the reconstruction of the early Paleozoic evolution of the northern Gondwana margin. The youngest middle Ordovician (465 Ma) age of detrital zircons indicate a derivation from a fore- arc sedimentary basin along an early Paleozoic convergent margin, which collected sediments from nearby emerged lands consisting of early Paleozoic volcanic arcs and pre-Paleozoic sequences. The chemical composition of metasediments is characterized by negative Sr anomaly and depletion in heavy rare earth elements (HREE) and Y as compared to the upper crust. Normalized to chondrite values, the paragneiss shows a steep REE pattern with light-REE enrichment, negative Eu anomaly and flat heavy-REE pattern. All these features suggest a derivation form older active continental margins or island arcs. Detrital zircon ages cover a very large time span (3151 + 97 Ma to 465 + 8 Ma) and reveal a complex history of inheritance and recycling. The oldest ages obtained on relic cores and/or magmatic stages, mostly enriched in Hf (Zr / Hf ratios: 45-24) and devoid of Y, indicate a contribution from granitoid rocks of mainly crustal origin. The ages of detrital zircons highlight a derivation of the sedimentary supply from the Sahara craton and/or the Arabian-Numidian shield along the northeastern margin of Gondwana. This fit well with derivation of early Paleozoic metasedimentary formations in southern Sardinia and northern Apennine, pointing out a common origin and location of these sedimentary basins along the northern margin of Gondwana at the early Paleozoic. As regards the Variscan orogeny, the common middle Ordovician age of Lula paragneiss and nearby Lode orthogneiss highlight the role of Variscan tectonics in the assembly of different blocks of early-middle Paleozoic margin.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44825001","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":"Stratigraphic and structural reconstruction of an offshore sector of the Hyblean Foreland ramp (southern Italy)","authors":"S. Distefano, F. Gamberi, A. Stefano","doi":"10.3301/IJG.2019.12","DOIUrl":"https://doi.org/10.3301/IJG.2019.12","url":null,"abstract":"Through the seismo-stratigraphic analysis of new high- resolution seismic data acquired along the southwestern offshore of the Hyblean Plateau, this work aims to improve the knowledge about the stratigraphic and structural setting in the marine area connecting the Hyblean Plateau Foreland to the Gela-Catania Foredeep.Two main goals have motivated the acquisition of new seismic profiles along the southern coastline of Sicily, in the Marina di Ragusa offshore:(i) to obtain a better comprehension of the Cenozoic stratigraphic and structural setting of the area, with a particular attention to the characterization of the Pliocene-Holocene sedimentary deposits and their areal distribution;(ii) to identify, in the offshore area, the possible prolongation of the main structural lineaments outcropping in the hinterland (Scicli-Ragusa-Irminio Line), and verify the presence of structures, responsible for the tectonic activity affecting the area.Our model shows that an extensional fault system, characterized by a main NE-SW orientation, affects the highly deformed Oligo-Miocene, or older, substratum, originating structural highs and down-faulted sectors. These faults are inferred to record the early history of the Scicli Line and of the polyphase kinematic evolution of the N50° oriented regional fault systems.The Gessoso-Solfifera deposits (Messinian, Late Miocene) have been recognized in several sectors of the study area, showing a very peculiar seismic facies, and occupying deep erosional channels probably resting within down-faulted sectors. This feature is in good agreement with isolated onshore areas of the Hyblean Plateau (Licodia Eubea and south Vittoria villages) where the Gessoso-Solfifera deposits are associated to normal faults, thus documenting that Messinian evaporites are not restricted to compressive tectonic setting, such as the marginal sub-basins and the thrust top mini-basins of the Appennine-Maghrebian belt.A peculiar seismic facies has been associated to the Trubi Fm., unconformably lying upon the older succession.The undeformed seismic units, onlapping the older substratum, has been associated to the post-Trubi-Holocene deposits, arranged into seven seismic units that reflect the youngest depositional evolution of the nearby Catania-Gela Foredeep. These deposits, generally represented by plane-parallel seismic facies, are in turn separated by an unconformity highlighted by an onlap termination of the yougermost terms upon the older. In some cases they are interrupted by gas rising from the deeper succession that reaches, at times, also the seafloor.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2019.12","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46106580","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":"Neogene volcanism in Elazig-Tunceli area (eastern Anatolia): geochronological and petrological constraints","authors":"S. Agostini, M. Y. Savaşçın, P. D. Giuseppe, Flavio Di Stefano, Ö. Karaoǧlu, M. Lustrino, P. Manetti, Y. Ersoy, S. Kürüm, A. Önal","doi":"10.3301/IJG.2019.18","DOIUrl":"https://doi.org/10.3301/IJG.2019.18","url":null,"abstract":"The Elazig and Tunceli provinces in eastern Anatolia host a complex succession of Miocene-Pleistocene effusive and explosive volcanic rocks, divided into four distinct volcanic phases. The most abundant and widespread products are the calcalkaline Mazgirt volcanic rocks, characterized by wide Sr isotope variations (87Sr/86Sr ~0.7054-0.7077) and narrower 143Nd/144Nd (~0.51246-0.51260) and Pb isotopes (e.g., 206Pb/204Pb ~18.89-19.13). New 40Ar-39Ar ages indicate that Mazgirt volcanic activity occurred between ~16.3 and 15.1 Ma. The other three volcanic phases are represented by the Tunceli mildly alkaline basaltic lavas (~11.4-11.0 Ma), the Pliocene Karakocan (~4.1 Ma) and Pleistocene Elazig (~1.9-1.6 Ma) Na-alkali basaltic lavas with clear OIB-like geochemical signature.Mazgirt volcanics can be subdivided on the base of mode of emplacement into lava flows and lava domes units characterized by petrographic, chemical and isotopic differences: lava flows are calcalkaline, whereas lava domes mostly belong to a high-K calcalkaline series and are, on average, more LREE- and 87Sr-enriched. Lava domes are more porphyritic, with a phenocryst assemblage dominated by amphibole, whereas plagioclase and clinopyroxene are the most abundant phenocryst phases in lava flows, pointing out that evolution of dome magmas occurred in conditions of slightly higher pressure, favouring the crystallization of hydrous phases.The Karabakir Formation, previously reported as late Miocene- Pliocene, encloses Mazgirt volcanics and is capped by Tunceli basalts. These new age data constrain the Karabakir Formation emplacement from early to late Miocene.The evolution of this igneous activity mirrors the geodynamic framework of the region: the early-middle Miocene Mazgirt volcanics represent arc volcanism related to Eurasia-Arabia convergence. The late Miocene Tunceli basalts postdate the onset of post-collisional tectonics in Eastern Anatolia, whereas the Karakocan and Elazig volcanic rocks were emplaced after the initiation of strike-slip motion on the North Anatolian and East Anatolian Fault systems.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2019.18","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48873658","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":"Insights on the Capo d'Orlando flysch (NE Sicily) by means of geomechanics and sedimentology","authors":"S. Mineo, G. Pappalardo, C. Casciano, A. Stefano, S. Catalano, Marco Gagliano","doi":"10.3301/IJG.2019.13","DOIUrl":"https://doi.org/10.3301/IJG.2019.13","url":null,"abstract":"A multidisciplinary integrated approach for the study of heterogeneous rock masses is presented herein with the aim of providing a characterization of one of the widest flysch formations of northeastern Sicily. The Capo d'Orlando Flysch is indeed affected by a geotechnical heterogeneity arising from the alternation of sandstone banks and siltstone layers occurring in different proportions and showing peculiar features. This is the main responsible of the uneven mechanical strength offered by these different lithological compartments and deserves an in-depth study. To this purpose, an integrated sedimentological-geomechanical study is the focus of this research, which was initially carried out through rock mass surveys aimed at recognizing the different facies associations and their distribution along selected outcrops. Sedimentological logs were followed by rock mass geomechanical surveys for the assessment of the quality of the rock and its discontinuities. All these elements concurred in the definition of the Geological Strength Index, which is preparatory for the estimation of the main mechanical properties of the rock mass through the Hoek and Brown failure criterion. Results show that the lithological compartments occurring within flysch rock masses strongly condition their mechanical attitude. In fact, sandstone portions behave as massive/fractured rock mass characterized by specific geomechanical properties, which are lowered by the presence of siltstone layers. For this reason, the definition of the facies associations (F.A.) affecting the rock mass, along with their geomechanical characterization, is a useful integrated activity to avoid overestimating or underestimating the mechanical attitude of flysch rock masses, especially when engineering geological works have to be designed.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42568566","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":"Syn-kinematic sedimentary systems as constraints on the structural response of thrust belts: re-examining the structural style of the Maghrebian thrust belt of Eastern Sicily","authors":"R. Butler, R. Maniscalco, P. Pinter","doi":"10.3301/IJG.2019.11","DOIUrl":"https://doi.org/10.3301/IJG.2019.11","url":null,"abstract":"We are indebted to the generosity of the late Fabio Lentini. While he may not have agreed with our findings, he nevertheless openly and cheerfully shared his mapping and insight of Sicilian geology. This work also builds upon many years’ collaboration between us, initiated by the late Mario Grasso (the Pantagruelian Master of Speranza et alii, 2018). The mapping of Lentini, Grasso and colleagues represents a remarkable resource for future geologists. We dedicate this contribution to their memory. We thank Sveva Corrado and an anonymous referee for constructive comments on an earlier draft of this paper. Butler’s Sicilian field research has been variously funded by the UK’s Natural Environment Research Council and the Royal Society. Maniscalco acknowledges “Fondi per la Ricerca di AteneoPiano per la Ricerca 2016/2018”. Pinter was supported through a PhD grant funded by the BG Group (now Shell) and Brazil’s National Council for Scientific and Technological Development (CNPq).","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43700611","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":"Neogene stratigraphic evolution of a tectonically controlled continental shelf: the example of the Lampedusa island","authors":"S. Distefano, F. Gamberi, N. Baldassini, A. Stefano","doi":"10.3301/IJG.2019.17","DOIUrl":"https://doi.org/10.3301/IJG.2019.17","url":null,"abstract":"Lampedusa Island represents a key-area due to its central position within the Sicily Channel and the whole Mediterranean region. The acquisition and interpretation of sixteen “sparker-system” seismic lines allowed a refined reconstruction of the sedimentary architecture of the Lampedusa continental shelf and the detailed timing of its tectonic evolution, providing a contribution to the geodynamic processes affecting this sector of the Sicily Channel.The offshore profiles show five seismic facies, which have been compared with the onshore succession. The older seismic unit (S1) was correlated with the pre-rift Cala Pisana Mb. of the Lampedusa Fm., separated by the overlain Capo Grecale Mb. (=S2) by an erosional surface, identified with the offshore TU (=Tortonian Unconformity) horizon, passing upward to the Vallone della Forbice Mb. (=S3) through a gradual, concordant boundary (Upper Tortonian Boundary=UTB). Capo Grecale and Vallone della Forbice Mbs., and thus the S2 and S3 units, represent the syn-rift deposits, recording the Late Miocene extensional tectonic activity. The effects of the strong erosional phase connected with the Mediterranean Salinity Crisis of Messinian age, are visible in all the seismic lines coinciding with a high impedance irregular surface (MH=Messinian Horizon), above which a further seismic unit (S4) develops. This latter, constituted by reflections onlapping the substratum, in the lower part, and prograding in the upper one, does not find an onshore correspondence, but has been attributed to the post-Messinian (Zanclean) transgression, followed by the subsequent regressive phase (Piacenzian-Gelasian). The uppermost seismic unit (S5), unconformably covering the older substratum, through the Early Pleistocene Unconformity (=EPU horizon) corresponds to the Pleistocene-Holocene onshore deposits. The seabed (top of S5) shows regular morphologies in the southern sector, while in the northern sector it is cut by erosive channels connected to strong streams on the bottom.From a structural point of view, the southern sector recorded an extensional tectonic phase, giving rise to normal faults involving units from S1 to S3, sutured by the MH and the overlain deposits. In the northern sector, the tectonic phase continued until the Pliocene, also involving the S4 unit.The reconstructed tectonic setting well fits the more general setting of the Sicily Channel Rift Zone, where main WNW-ESE faults were active during the Late Miocene and until the Pliocene age, generating small depositional areas, bounded by second-order NNW- SSE normal faults.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2019.17","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43823156","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":"Tectonics control on Quaternary sedimentary processes and basin infill from the coastal area to the basin plain: examples from the Capo d'Orlando Basin (Southeastern Tyrrhenian Sea)","authors":"F. Gamberi","doi":"10.3301/IJG.2019.10","DOIUrl":"https://doi.org/10.3301/IJG.2019.10","url":null,"abstract":"Tectonic activity can affect every single segment of a sedimentary system and the various environments within a basin react in specific ways to tectonic forcing. However, the outcomes of tectonic activity on one environment have important consequences on the sedimentary processes in adjacent ones. In this paper, I evaluate the relationships between tectonic activity and sedimentary processes in several distinct environments, and in different times within the last sea- level cycle, in the submarine part of a single sedimentary system: the Capo d'Orlando Basin. The study area is located in the southeastern Tyrrhenian Sea along the northern Sicilian margin and is affected by active tectonics. A multibeam bathymetric coverage, chirp and regional sparker profiles are available over the study area. In the shelf, the Caronia Horst controls the thickness of the high stand systems tract and the character and the preservation potential of the coastal deposits of the transgressive systems tract. Coastal physiography, due to differential vertical movements, affects offshore current strength and pattern of sediment transport, causing the sand-mud line to move offshore. In the upper slope, tilting increases sediment instability and the accumulation of landslide deposits. Uplift, responsible for the local shallower depth of the shelf edge, favoured the connection between canyon heads and river mouths during the last sea-level low stand. More importantly, some of the canyon heads are still close to the coast and can receive sediment from rivers or offshore currents even during the present-day high stand. The Naso and the Calava Channels have fault-controlled courses and an asymmetric profile, which controls the location of overbank flows, sediment failures and landslide deposition. In the basin plain, the continued activity of the major faults has created subtle topography and the turbidite lobes do not present a compensational stacking pattern but remain fixed in fault-controlled lows; differential compaction in the separate fault blocks also contribute to differences in turbidite thickness. Landslides are present at the base of the fault-controlled basin-bounding escarpments and punctuate the otherwise turbidite-dominated succession. The analysis of the Capo d'Orlando Basin illustrates the range of effects that tectonic structures have on sedimentary processes going from the continental shelf to the basin plain. More importantly, although in a qualitative way, this research shows how the tectonic influence on up-dip processes is also responsible for the nature of the depositional record in the deeper part of the basin.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42342741","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":"The ancient quarrying areas of the sandstones used in the UNESCO historical centre of Urbino (Marche, Italy) as inferred from geological, petro-chemical and physical-mechanical investigations","authors":"P. Santi, F. Veneri, G. Tonelli, A. Renzulli, F. Antonelli, M. Tramontana","doi":"10.3301/IJG.2019.15","DOIUrl":"https://doi.org/10.3301/IJG.2019.15","url":null,"abstract":"Many buildings of the historical centre of Urbino (Marche, Central Italy), included in the UNESCO World Heritage List, are characterized by portals consisting of sedimentary rocks such as limestones or sandstones. In order to identify the possible quarries of provenance of sandstones used for architecture, we addressed our research to the Sant'Ippolito area (20 km ESE of Urbino), where historical stonemasons have been extensively documented since the 14th century. Few traces of ancient exploitation indicate some extraction sites. All the investigated rocks (both from monumental portals of Urbino and geological outcrops) consist of fine- to medium- grained sandstones with a variable content of bioclasts. Two different groups were recognized (using the petrographic Q-F-R classification diagram): (i) lithic arenites belonging to the Colombacci Formation; and (ii) feldspathic lithic arenites referable to the Tripoli Unit. In particular, petrographic data indicate that the sandstones used in the historical buildings of Urbino, come from the arenitic lithofacies of the Messinian p.p. Colombacci Formation of the Sant'Ippolito area. In addition, comparative geochemical studies of whole rock major and trace elements point out three outcrops of the above formation, as possible sites of ancient extraction. Sandstones of the Tripoli Unit and the Marnoso-Arenacea Formation, widespread in the study area and near Urbino respectively, are ruled out as source rocks, based on both petrographic and geochemical data.Anomalously high values of some heavy elements such as Pb, Zn and As, recognized in some of the portals, likely derive from a combination of various anthropogenic sources of pollution close to the investigated monuments, such as domestic heating and emissions from road traffic in the past.From a mechanical point of view, the uniaxial compressive strength tests, carried out on a representative number of selected samples of the Colombacci Formation lithic arenites, yelded low values and high variability. Other investigated physical parameters also indicate that the stones used for the portals did not represent a good choice as building material. This implies that the stonemasons of Sant’Ippolito chose local raw materials for their availability, aesthetic qualities and good workability, rather than structural properties.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2019.15","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44733978","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":"Tectonic controls on sedimentary system along the continental slope of the central and southeastern Tyrrhenian Sea","authors":"F. Gamberi, G. Valle, M. Marani, A. Mercorella, S. Distefano, A. Stefano","doi":"10.3301/IJG.2019.08","DOIUrl":"https://doi.org/10.3301/IJG.2019.08","url":null,"abstract":"Continental margins are often characterised by wide slope sectors with complex topography due to seafloor deformation linked with mobile shale or salt, or local tectonics. Within the resulting slope environments, sedimentary systems can be complex and often structured in variously connected, separate intraslope basins. In this paper, we investigate how the diverse arrangement of sedimentary systems on topographically complex slopes relate to regional differences in extensional tectonic setting. Our study is carried out through the analysis of bathymetric data in the central and southeastern portion of the Tyrrhenian Sea, a back-arc basin that displays wide slope sectors, surrounding the deep Marsili and Vavilov basin plains. A “connected tortuous corridor” forms in the Latium-Campanian slope, where extensional faults are parallel to the margin. Here, tectonic structures are important in controlling the relative extent of dip and strike sectors as well as depositional and erosional segments of submarine drainage networks. Confined, margin-parallel troughs, such as the Capo d’Orlando and the Paola Basins, form respectively landward from volcanic edifices and mud remobilisation ridges. Their depositional setting is mainly the result of the relationships between the basin dip and the site of major sediment input. An unconfined trough parallel to the margin forms when its edge coincides with down-to the basin extensional faults, such as in the case of the Gioia Basin. Its axis is the site of a longitudinal slope valley that shows morphologic variations controlled by tectonic structures. Transverse troughs cutting the entire slope form when tectonic structures are perpendicular to the margin, such as in the Cilento slope. Here, the pattern of extensional faulting is the major control on the degree of connection of successive basins and the eventual development of a drainage system. Throughgoing slope valleys form in graded slope, where sedimentary packages are thick enough to heal the relief associated with tectonic structures. They have planforms, relief and erosional or depositional attitude that is controlled by slope steps connected with faults. As a general outcome, our research provide a valid framework that illustrates the range of possible architectures of sedimentary systems and of their constituents in extensional continental margins.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49199772","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":"Facies analysis in the Second Cycle Messinian evaporites predating the early Pliocene reflooding: the Balza Soletta section (Corvillo Basin, central Sicily)","authors":"R. Maniscalco, C. Casciano, S. Distefano, F. Grossi, A. Stefano","doi":"10.3301/IJG.2019.06","DOIUrl":"https://doi.org/10.3301/IJG.2019.06","url":null,"abstract":"The thick evaporitic deposits cropping out widely in central Sicily are subdivided into First and Second Cycle Evaporites, separated by a regional unconformity, and are spectacularly exposed in the Balza Soletta section of the Corvillo Basin, one of the main depocenters of the Caltanissetta Basin. Here, the evaporitic succession mainly consists of Second Cycle fan-delta conglomerates and gypsarenites, onlapping the First Cycle Evaporite units.A detailed sedimentological analysis of the whole succession, coupled with the study of the microfossil content (foraminifers, calcareous nannofossils and ostracods) of selected samples representative of the different facies, indicates that the deltaic deposits of the Second Cycle record a continuous overall fining- and deepening-upward trend with a waning clastic input, likely registering a gradual reflooding. The microfossil associations (mainly ostracods and benthic foraminifers) agree with the existing data on the microfauna populating the upper Messinian Lago-Mare in Sicily before the early Pliocene reflooding, supporting the sedimentological interpretation and the hydrodynamic connection with the Paratethys.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2019.06","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45445442","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}