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Recent works documented Neogene to Quaternary dextral strike-slip tectonics along the Kuh-e-Sarhangi and Kuh-e-Faghan intraplate strike-slip faults at the northern edge of the Lut Block of Central Iran, previously thought to be dominated by sinistral strike-slip deformation. This work focuses on the evidence of Quaternary activity of one of these fault systems, in order to provide new spatiotemporal constraints on their role in the active regional kinematic scenario. Through geomorphological and structural investigation, integrated with optically stimulated luminescence dating of three generations of alluvial fans and fluvial terraces (at ~53, ~25, and ~6 ka), this study documents (i) the topographic inheritance of the long-term (Myr) punctuated history of fault nucleation, propagation, and exhumation along the northern edge of Lut Block; (ii) the tectonic control on drainage network evolution, pediment formation, fluvial terraces, and alluvial fan architecture; (iii) the minimum Holocene age of Quaternary dextral strike-slip faulting; and (iv) the evidence of Late Quaternary fault-related uplift localized along the different fault strands. The documented spatial and temporal constraints on the active dextral strike-slip tectonics at the northern edge of Lut Block provide new insights on the kinematic model for active faulting in Central Iran, which has been reinterpreted in an escape tectonic scenario.

""Data constraining the paleoenvironmental conditions during the Messinian evaporative drawdown of the. Mediterranean basin are still conflicting. Here we present a comprehensive paleoclimatic reconstruction. during Messinian halite deposition from several Italian sites. We performed fluid inclusion analyses to define. better both the composition of the Mediterranean water body and the paleotemperatures of the Messinian. brine during halite crystallization. We measured homogenization temperatures on 218 primary all-liquid fluid. inclusions in Messinian halite from the Volterra, Crotone, and Caltanissetta evaporite basins. These. measurements provided mean homogenization temperatures of 17–18C, with a range between 10–11C and. 28–29C, which should be close to the SST of the Mediterranean Sea during halite deposition. The occurrence. of major elements such as Cl, Na, Mg, S, Ca, and K within the halite fluid inclusions, together with the. presence of minerals such as pentahydrite, polyhalite, and Ca-, K-, and Mg-sulfates, indicates that these salt. bodies originated from mainly marine water. Taking into account both the present-day annual SST of the. Mediterranean Sea around the sampling sites, which ranges between 18 and 20C, and the lower latitude of. the Mediterranean Basin during the Messinian Salinity Crisis, our homogenization temperatures point to a. colder climate during the Messinian halite deposition compared to the present interglacial climate stage. This. conclusion is consistent with halite deposition during a Late Miocene glacial interval (TG12).""

""The geological mapping of the sheets 366 “Palombara Sabina” and 375 “Tivoli” (1: 50.000 scale; CARG Project; in preparation) allowed the revision of the structural setting of the westernmost portion of this part of the Neogene fold-and-thrust belt of the Central Apennines.. The area comprises the Cornicolani, Lucretili, eastern Sabini, Tiburtini, Ruffi and Prenestini Mts (Latium region). Most of the area (Cornicolani, Lucretili and Tiburtini Mts) is made of the pre-orogenic deposits (Upper Triassic-Serravallian) referred to the calcareous-marly-siliceous Sabina Succession, that were accumulated in the southern part of the Umbria-Marche-Sabina Pelagic Basin (Sabina Domain), proximal to the Latium-Abruzzi Carbonate Platform. In general, in the eastern areas, more proximal to the platform, coarser lithofacies crop out. Moreover, in the Cornicolani and western Lucretili Mts (Castelvecchio Mt) areally restricted outcrops of condensed pelagic carbonates (Bugarone Group and calcari dolomitici di S. Angelo Romano) document the occurrence of Jurassic intrabasinal structural highs evolved into Pelagic Carbonate Platforms. These structural highs were generated after the Early Jurassic rifting, that broke-up the pre-existing carbonate platform (Calcare Massiccio).. In the mapped area, the Latium - Abruzzi Platform is represented in the hangingwall of the Olevano-Antrodoco line only in the southern Prenestini Mts (Rocca di Cave), by upper Cretaceous shelf carbonates. Whereas in the footwall of the Olevano-Antrodoco line it crops out along the Aniene River valley.. Both Sabina and Latium - Abruzzi successions are overlain by upper Tortonian - lower Messinian marls and siliciclastic syn-orogenic deposits, best observed in the easternmost areas and inbetween the Ruffi and Prenestini Mts.. In their turn, the syn-orogenic deposits are unconformably overlain by post-orogenic Plio-Pleistocene marine clastic deposits and Quaternary volcanic and alluvial sediments. From a structural point of view, the Sabina Domain is arranged into several thrust sheets verging toward the east, developed in middle-late Miocene-early Pliocene times. The early Pliocene Olevano-Antrodoco out-of-sequence thrust marks the eastern tectonic boundary of this structural domain where the pelagic and slope sediments overthrust the Latium - Abruzzi Carbonate Platform and its associated syn-orogenic deposits. In late Miocene-early Pliocene extensional tectonics down-threw the western border of this imbricated structure enhancing the marine ingression along the peri-Tyrrhenian margin. The western border of the region was also reactivated by N-S right-lateral strike-slip fault dissecting the earlier structures in Pleistocene times.. From top of the orogenic edifice three main tectonic units have been identified:. - Unit 1 (Morra Mt) made up of Upper Triassic to Lower Jurassic dolomite limestones (Dolomia Principale) and Calcare Massiccio, overthrust onto unit 2.. - Unit 2 (comprising Cornicolani Mts, western Lucretili Mts) made up of Dolomia Principale, Calcare Massiccio, Corniola detritica and, in the Cornicolani and western Lucretili Mts, Bugarone Group. Long wavelength upright folds mainly characterize this unit and faults with high angle cuts-offs prevail, and Jurassic structural highs occur (Cornicolani Mts, Castelvecchio Mt).. - Unit 3 (comprising Elci Mt, eastern Lucretili Mts and Tiburtini Mts) made up of most of the Sabina basin stratigraphic succession - from Corniola detritica Fm. to the Guadagnolo Member (marly lithofacies); the unit is characterized by NW to NE verging overturned to recumbent folds. - Unit 4 (comprising Prenestini Mts, Ruffi Mts and eastern Sabini Mts) made up of the upper portion of the basin succession between the Marne a Fucoidi and Upper Miocene siliciclastics and the Rocca di Cave carbonate platform succession.. This unit is made up by two sub-units, based on the deformation-style and stratigraphy: the sub-unit 4A (Granaro Mt, Colle Serviano and Arzillo Mt in the western Prenestini Mts), is mainly characterized by east-verging packed asymmetrical folds with sub-vertical axial-planes, and N-S striking dextral-transpressive faults. The sub-unit 4B (Castel Madama area, eastern and central Prenestini Mts, Ruffi Mts and eastern Sabini Mts) is characterized by a wide symmetrical anticline in the western portion, and by folds with very steep axial planes, and N-S to NNW-striking dextral transpressional faults.. The units are separated by low-angle thrusts or by high-angle transpressive faults: the stratigraphic successions characterizing each unit rejuvenate eastward.. The innermost unit 1 and unit 2, where massive or poorly stratified deposits are exposed, are mainly deformed by high angle faults. Whereas the more external unit 3 and unit 4 are composed by alternating carbonate, marls and siliciclastics, and are mostly characterized by east-verging slightly to strongly asymmetrical and overturned folds.. A new geometric and kinematic scenario for the Neogene evolution of the units preserved in the hangingwall of the Olevano-Antrodoco thrust is here outlined.. The revision of the stratigraphy and structural data put in evidence the presence of paleo-structures of the Tethyan passive margin not evidenced in the past cartography, their influence on Neogene compressive structures and the coexistence of non-coaxial structural trends in areas of limited extension."" ""Il rilevamento dei fogli geologici 366 “Palombara Sabina” e 375 “Tivoli” (Progetto CARG) ha comportato la revisione dell’interpretazione dell’assetto strutturale della porzione più occidentale dell’Appennino Centrale. L’area esaminata comprende i Monti Cornicolani, Lucretili, Sabini orientali, Tiburtini, Ruffi e Prenestini, caratterizzati dall’affioramento di depositi meso-cenozoici pre-orogenici di piattaforma carbonatica annegata, di bacino, di transizione (Dominio paleogeografico Sabino) e di piattaforma carbonatica persistente (Piattaforma Laziale-Abruzzese), e di depositi sin-orogenici silicoclastici miocenici. Le unità tettoniche del Dominio Sabino si accavallano su quelle della Piattaforma Laziale-Abruzzese lungo la Linea Olevano-Antrodoco Auctorum.. Il Dominio Sabino è stato suddiviso in quattro Unità tettoniche (partendo da quella superiore):. Unità 1 (M. Morra);. Unità 2 (Monti Cornicolani, Monti Lucretili occidentali);. Unità 3 (M. degli Elci, Monti Lucretili orientali, Monti Tiburtini);. Unità 4 (Monti Sabini orientali, Monti Ruffi, Monti Prenestini), in cui si distinguono la sub-unità 4A (Monti Prenestini occidentali) e la sub-unità 4B (Monti Sabini orientali, di Castel Madama, Ruffi e Prenestini centro orientali).. In questo assetto strutturale, le principali novità riguardano l’individuazione di paleostrutture giurassiche (in particolare un alto strutturale nei Monti Lucretili occidentali), la loro influenza sullo sviluppo della deformazione compressiva, e una più dettagliata definizione di trend compressivi non-coassiali già evidenziati nella presistente cartografia.""

Dans ce travail, les ostracodes trouv´es dans dix complexes coralliens du Mioc`ene sup´erieur construits par Siderastrea, Tarbellastrea et Porites, localis´es dans la plaine de Messara (zone m´eridionale du bassin de l’Iraklion, Cr`ete centrale) sont ´etudi´es et illustr´es. Cinq diff´erentes associations caract´eristiques des divers environnements marins ont ´et´e reconnues par : (1) association des couches silteuses basales, caract´eris´ee par des esp`eces typiques des eaux marines du domaine infralittoral sup´erieur, parmi lesquelles Cyamocytheridea meniscus, Cyamocytheridea obstipa, Cyamocytheridea dertonensis, Cytheretta semiornata et Nonurocythereis seminulum sont tr`es repr´esent´ees ; (2) association des couches r´ecifales avec Grinioneis haidingeri, Aurila cicatricosa, Cimbaurila diecii, Tenedocythere cruciata, Pokornyella italica et Callistocythere quadrangula dominants qui indiquent un environnement marin infralittoral sup´erieur stable, caract´eris´e par des eaux chaudes et bien oxyg´en´ees ; (3) association des couches silteuses interpos´ees entre les complexes coralliens, parmi lesquelles Neomonoceratina laskarevi, Cytheridea acuminata, Phlyctenophora farkasi, Aurila albicans Callistocythere spp., Xestoleberis communis et X. dispar sont dominants. Ces esp`eces indiquent des eaux peu profondes avec v´eg´etation aquatique ; (4) association des couches silteuses sup´erieures, domin´ee par la pr´esence du genre Xestoleberis, caract´eristique des environnements marins moins profonds et tr`es riches en flore aquatique et (5) association des couches argilosilteuses terminales, domin´ee par Hemicytherura defiorei, Ostracods from ten Late Miocene coral reef complexes built by Siderastrea, Tarbellastrea and Porites, cropping out in the Messara Plain (southern Iraklion basin, central Crete), have been investigated and five assemblages have been recognised, which point to different marine environments: (1) assemblage from the basal sandy silts, dominated by very shallow inner-infralittoral species, such as Cyamocytheridea meniscus, Cyamocytheridea obstipa, Cyamocytheridea dertonensis, Cytheretta semiornata and Nonurocythereis seminulum; (2) assemblage from the coral reef complexes within which Grinioneis haidingeri, Aurila cicatricosa, Cimbaurila diecii, Tenedocythere cruciata, Pokornyella italica and Callistocythere quadrangula are dominant and point to a stable inner-infralittoral environment characterised by warm, quiet and well-oxygenated waters; (3) assemblage from the silts intercalated among the coral reef complexes, mainly characterised by Neomonoceratina laskarevi, Cytheridea acuminata, Phlyctenophora farkasi and Aurila albicans together with Callistocythere spp., Xestoleberis communis and Xestoleberis dispar, which points to a very shallow marine environment rich in aquatic vegetation; (4) assemblage from the upper silts, which records the absolute dominance of Xestoleberis species, reflecting a very shallow and highly-vegetated environment and (5) assemblage from the uppermost silty clays, dominated by Hemicytherura defiorei, Xestoleberis spp. and Palmoconcha dertobrevis, accompanied by Acanthocythereis hystrix, Cytherella scutulum, Bairdoppilata conformis, Semicytherura spp., Krithe sp., Cytheropteron alatum, Bythocypris sp. and Pseudocythere caudata, which suggest deeper marine environments probably located in the outer infralittoral/inner-circalittoral zones. The studied section has been dated by means of calcareous nannoplankton to be not younger than Zone MNN9 (Early Tortonian), which is the biostratigraphical datum recorded in the fine-grained deposits that overlie the coral reef complexes. An age not older than Tortonian can be inferred by the stratigraphical distribution of the recognized ostracods. Thus, the coral reef complexes have been tentatively referred to the Early Tortonian.

È stata misurata la radioattività naturale (NRD) di tre successioni stratigrafiche del Messiniano nella Maiella nord-occidentale (Trovigliano-Abbateggio, PE). Complessivamente, le tre successioni analizzate (cava Buzzi-Unicem; cava Lafargessi; cava Colle di Votta) comprendono tutto il Messiniano evaporitico e la base di quello postevaporitico. I differenti valori di radioattività misurati corrispondono alle principali litofacies che caratterizzano la Formazione Gessoso- Solfifera affiorante nell’area di studio. In particolare, il profilo dell’emissione gamma, acquisito sul terreno, mostra picchi di attività in corrispondenza delle argille euxiniche, alla base della successione evaporitica, e in corrispondenza degli orizzonti sapropelitici intercalati alle bancate di gesso. All’interno di queste ultime, la bassa radioattività tende ad aumentare in presenza di componente carbonatica, che può costituire la matrice delle bancate di gesso e/o può essere presente in livelli o strati. I valori maggiori di radioattività sono stati misurati nei depositi messiniani post-evaporitici, in corrispondenza di marne laminate di colore marrone e di calcari brecciati. Il contributo dei radioelementi naturali (238U, 232Th e 40K) varia nelle diverse litofacies analizzate. In particolare, mentre i sapropel sono caratterizzati da rapporti Thppm/Uppm ≥ 1, i gessi e le facies carbonatiche hanno rapporti Thppm/Uppm <

Recenti lavori per la costruzione, nella città di Roma, del Passante a Nord-Ovest (Galleria Giovanni XXIII) hanno permesso di raccogliere nuovi dati circa la stratigrafia e l’assetto tettonico del settore dei Monti della Farnesina, in riva destra del F. Tevere. Le gallerie naturali del Passante a Nord-Ovest hanno attraversato la successione plio-pleistocenica di Monte Mario, che è stata suddivisa in due formazioni: la formazione di Monte Vaticano e la formazione di Monte Mario. Quest’ultima, poggiante in discordanza stratigrafica al disopra della formazione di Monte Vaticano (Marne Vaticane Auct.), è stata distinta in cinque membri: 1) Limi di Farneto; 2) Sabbie grigie ad Arctica islandica; 3) Sabbie gialle con panchina; 4) Sabbie gialle con intercalazioni limose; 5) Argille, sabbie e limi con Cerastoderma. La forte troncatura erosiva osservata al top della formazione di Monte Vaticano suggerisce la presenza di un’ampia lacuna stratigrafica erosivo-deposizionale, tra questa e i soprastanti depositi della formazione di Monte Mario. Le analisi biostratigrafiche e paleoecologiche condotte in questo studio hanno messo in evidenza differenze sostanziali tra la formazione di Monte Vaticano (Marne Vaticane Auct.) e i soprastanti Limi di Farneto. Le Marne Vaticane Auct. campionate lungo il Passante a Nord-Ovest hanno fornito associazioni di plancton calcareo riferibili allo Zancleano inferiore (3.85-3.58 Ma). L’analisi paleoecologica condotta sulle ostracofaune indica, per le Marne Vaticane Auct., un ambiente batiale superiore, con paleoprofondità comprese tra –200 e –350 m. Per quanto emerso dall’analisi dei nannofossili calcarei, i Limi di Farneto sono collocabili al disopra della FO di medium Gephyrocapsa (Santerniano inferiore). Inoltre, per la sostanziale assenza di C. macintyrei e per la presenza di B. etnea, è possibile limitare l’età dei Limi di Farneto all’interno dell’intervallo 1,60-1,49 Ma (Santerniano superiore). L’analisi paleoecologica dell’orizzonte basale dei Limi di Farneto ha fornito indicazioni di un ambiente infralitorale esterno, con paleoprofondità di circa –40 m e un abbassamento relativo del livello del mare di almeno 160 m. Tale abbassamento relativo ha un’origine prevalentemente tettonica, dal momento che le Marne Vaticane Auct. risultano interessate da sistemi di faglie estensionali suturate dalla soprastante formazione di Monte Mario. All’interno della formazione di Monte Mario, l’analisi paleoecologica condotta sulle ostracofaune ha consentito di riconoscere due diverse sequenze deposizionali, separate da una superficie di discontinuità, legata ad un momento di abbassamento relativo del livello del mare, che definisce il limite Sabbie gialle con panchina\Sabbie gialle con intercalazioni limose. La base delle Argille, sabbie e limi con Cerastoderma corrisponde ad un secondo evento trasgressivo, riconosciuto all’interno della formazione di Monte Mario, che ha portato alla deposizione di argille marine di ambiente infralitorale, come la base dei Limi di Farneto, caratterizzate, ancora, dalla presenza di medium Gephyrocapsa. L’analisi strutturale e le indicazioni del fabric magnetico, indicano che l’alto di Monte Mario si è strutturato in due fasi tettoniche estensionali distinte: 1) una prima fase, sviluppata su piani NE-SW, collocabile prima della deposizione della formazione di Monte Mario (pre Santerniano superiore); 2) una seconda fase sviluppata su piani NW-SE, in un intervallo temporale compreso tra 750-600 ka. Infine, i caratteri paleomagnetici delle formazioni di Monte Mario e di Monte Vaticano mostrano componenti di polarità inversa ben definite, attribuite sulla base dei dati biostratigrafici, rispettivamente, all’epoca MATUYAMA ed alla parte superiore dell’epoca GILBERT.

La successione tardo messiniana di Fonte dei Pulcini (FPA) (Maiella sud-orientale), deposta in un bacino di avampaese, ha registrato numerose variazioni paleoambientali in termini di paleoprofondità, paleosalinità, apporto detritico, evaporazione/precipitazione e aridità/umidità. Queste variazioni paleoambientali sono state messe in evidenza attraverso l’analisi integrata di dati paleontologici, geochimici e mineralogici. L’analisi della suscettività magnetica nella successione di FPA ha permesso di effettuare una calibrazione astrocronologica delle variazioni paleoambientali e paleoclimatiche, vincolando la sezione tra 5,394 e 5,335 Ma. Confrontando la curva dell’insolazione con le variazioni paleoambientali registrate dalla sezione FPA è stato messo in evidenza un ritardo di 5-8 ka tra la causa astronomica della variazione climatica e la risposta del bacino sedimentario.

A high-resolution stratigraphic model for the uppermost Messinian deposits of the Mediterranean basin is here proposed. The model provides new constraints for calibrating the time and space distribution of palaeoenvironmental proxies of the final phase of the Messinian salinity crisis (MSC), characterized, after the main phase of massive evaporite precipitation, by the progressive and generalized establishment of brackish to freshwater aquatic environments throughout the Mediterranean basin (‘Lago Mare event’). The corresponding stratigraphic unit, bounded by the intra-Messinian unconformity (MES) at the base (~5.6 Ma) and the M/P boundary at top (5.33 Ma) is split into two sub-units by a minor unconformity marking a sharp facies change. The lower sub-unit (p-ev1) is localized in deepest and/or strongly subsiding basins and is commonly characterized by ‘regressive’ depositional trends. It records the transition from hyper- to hypohaline conditions over a short time span characterized by an acceleration of tectonic processes in many Mediterranean geodynamic contexts. The upper sub-unit (p-ev2) is more basin-wide distributed and records the generalized periodic activation of catastrophic flood-dominated fluvio-deltaic depositional systems, indicating important modifications in the drainage areas and/or in fluvial runoff. In this sub-unit four to five precessional cycles are usually recognized below the Miocene/Pliocene boundary, allowing basin-wide correlations and suggesting to place its basal age at around 5.42 Ma. While p-ev1 records the local and ephemeral development of Lago Mare environments with low-diverse, pioneer taxa, p-ev2 is marked by the diffusion of conspicuous brackish to freshwater fossil assemblages of increasing diversity and complexity upwards. The change is best approximated by the boundary between the two sub-units. No clear evidence of normal marine conditions established before the Zanclean flooding have been recognized. Converging sedimentary evolution and paleontologic record suggest that the last MSC phase was characterized by a dilution of the surface waters of a large, residual Mediterranean water body with strongly reduced ocean connections. These conditions likely resulted from a positive feedback loop between processes (increase of fluvial runoff, generalized subsidence, base-level rise, enlargement of shelf areas) promoting the establishment of progressively larger, more stable intra-basinal connections and water exchanges with the Paratethyan basins, up to the final full reopening of the Atlantic gateways.