Italian Journal of Geosciences最新文献

{"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":null,"pages":null},"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":null,"pages":null},"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":null,"pages":null},"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":null,"pages":null},"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":null,"pages":null},"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":null,"pages":null},"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":null,"pages":null},"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}

{"title":"In search of the Burdigalian GSSP: new evidence from the Contessa Section (Italy)","authors":"Alessio Fabbrini, N. Baldassini, C. Caricchi, L. Foresi, L. Sagnotti, J. Dinarès‐Turell, A. Stefano, F. Lirer, M. Menichetti, A. Winkler, S. Distefano","doi":"10.3301/IJG.2019.07","DOIUrl":"https://doi.org/10.3301/IJG.2019.07","url":null,"abstract":"The Contessa Section is a reference section for the early Miocene in the Mediterranean. Along this 36 m thick section 115 samples were collected and analysed for an integrated bio-magnetostratigraphic study through the Scaglia Cinerea and Bisciaro formations. Planktonic foraminifera were analysed semi-quantitatively, while calcareous nannofossils were examined using the standard quantitative method. A reliable biozonation for both fossil groups was then accomplished. The paleomagnetic analyses identified a sequence of magnetozones, then correlated with the ATNTS using the calcareous plankton bioevents. The investigated interval extends from foraminiferal Zone P22 (Chattian) to MMi2c (Burdigalian) and from calcareous nannofossils Zone MNP25a to MNN3a, thus from Chron C7An to C5En. Therefore, the section chronologically spans from 24.80 Ma to18.10 Ma. Three hiatuses were recognised along the section: H1 at 0.63 m from the base (comprising a minimum time interval from 24.36 Ma to 23.38 Ma), H2 at 12.33 m (between 21.80 Ma and 21.35 Ma) and H3 at 34.03 (between 19.21 Ma and 18.40 Ma). All three hiatuses were correlated with regional megahiatuses identified in the North Atlantic Ocean and in the Paratethys area. Furthermore, the First Occurrenceof the calcareous nannofossil Helicosphera ampliaperta is recognised within Chron C6An.2n at 19.77 m from the base (6 m above the volcaniclastic Raffaello Level). This event provisionally defines the Aquitanian/Burdigalian boundary according to the literature. Thus, the Contessa Section is a possible candidate for the definition of theBurdigalian Global Stratigraphic Section and Point. Finally, the age of the Raffaello Level (a regional marker horizon for the early Miocene) is discussed in this new integrated stratigraphic framework, falling in Chron C6AAn and dated between 21.09 Ma and 21.08 Ma.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2019.07","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45997551","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 origin of gas seeps in the Northern Adriatic Sea","authors":"F. Donda, U. Tinivella, E. Gordini, G. Panieri, V. Volpi, D. Civile, E. Forlin, L. Facchin, M. Burca, A. Cova, G. Ferrante","doi":"10.3301/IJG.2018.34","DOIUrl":"https://doi.org/10.3301/IJG.2018.34","url":null,"abstract":"A multidisciplinary approach has been used for the first time to study the widespread occurrence of hydrocarbon seeps in the northern Adriatic Sea. Geological, geophysical and geochemical analyses were performed to identify and characterize the gas-charged fluids occurring throughout the Plio-Quaternary succession, and to date the shallow gas seeping at three leakage sites. The analysis of CHIRP, morpho-bathymetric and multichannel seismic data allowed us toidentify different types of gas-related features, which occur within the whole Plio-Quaternary succession up to the seafloor and to the water column. Quantitative analyses of CHIRP data were conducted to better define, characterize and quantify the gas occurrence within the uppermost stratigraphic succession. CHIRP data also allowed the identification of the gas leakage sites. Three gas seepage areas were sampled with the aim to determine the gas composition and origin.The isotopic analyses revealed that seep gases are microbial in origin, and are primarily composed of methane, mostly formed within relatively laterally persistent Late Pleistocene peat layers, which are widely distributed throughout the northern Adriatic Sea and represent the main source of organic matter feeding the seeping gases.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2018.34","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48962859","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":"Low-angle normal faults record Early Permian extensional tectonics in the Orobic Basin (Southern Alps, N Italy)","authors":"A. Zanchi, S. Zanchetta, L. Berio, F. Berra, F. Felletti","doi":"10.3301/IJG.2018.35","DOIUrl":"https://doi.org/10.3301/IJG.2018.35","url":null,"abstract":"Well-preserved SSE-dipping low-angle normal faults (LANF) active during the Early Permian (Cisuralian) were recognized along the northern margin of the Orobic Basin (central Southern Alps, N Italy). These faults, which escaped most of the Alpine deformations, exhumed the Variscan basement during the deposition of the upperpart of the Lower Permian succession (Pizzo del Diavolo Formation).Fault planes show evidence of frictional processes typical of the upper crust associated with hydrothermal circulation, responsible for the deposition of cm to m thick tourmalinite and Uranium mineralization.The recognized LANFs interacted with high-angle normal faults producing half grabens that stored the Lower Permian deposits, where synsedimentary fault activity in their hangingwall is testified by abrupt vertical and lateral facies changes, thickness variations and by soft-sediment deformations. Mesoscopic structures, exposed in the hangingwall of a major LANF (the Aga-Vedello Fault system) along a synthetic high-angle normal fault, include conjugate normal faults, horst-and-graben, domino-style planar and listric faults, which clearly record synsedimentary deformations testified by liquefaction and dewatering structures, typical of pre-consolidation hydroplastic conditions. This exceptional record indicates deformations at shallow crustal level which occurred during the Early Permian along high-angle normal faults soling into the LANFs, forming the northern boundary of the Orobic Basin.The outcrop continuity, the perfectly preserved relationships among high- and low-angle normal faults together with the synsedimentary record of fault activity and the occurrence of mesoscopic faults developed during the deposition of the sediments, make this case-study an excellent reference for the analysis of extensional tectonics in synsedimentary conditions.In addition, the occurrence of large LANF systems, typical of a stress regime characterized by a vertical s1, suggests that the Lower Permian Orobic Basin was dominated by pure extension at least in the study area, alternatively to existing interpretations, which favor a transtensional origin of the basin. Strike-slip tectonics can be responsible for a later partial tectonic inversion of the basin, as testified by the angular unconformity with the overlying Upper Permian succession (Verrucano Lombardo), marking a Middle Permian stratigraphic gap.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45093045","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}