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In the southern Central Pontides in northern Turkey the remnants of two Neotethyan oceanic basins, currently represented by the Intra-Pontide and the Izmir-Ankara-Erzincan sutures, and the interposing continental microplate (i.e., the Sakarya Composite Terrane) are completely dissected by the North Ana-tolian Shear Zone (NASZ). Within the resulting kilometre-scale, strike-slip fault-bounded blocks, several Late Cretaceous arc-type magmatic units have been detected. In this paper, we present new geochemical data from one of these magmatic units, the Yerkuyu Unit, that forms an ENE-WSW trending 30-km long and 10-km wide lens-shaped body surrounded by the splays of the NASZ.The studied igneous lithologies have a subduction-related magmatic geochemical signature matching with another lozenge-shaped magmatic block of the Tafano Unit. However, the tectono-magmatic characterization indicates that the Tafano Unit magmatism developed within a continental arc tectonic setting, while the volcanic rocks of the Yerkuyu Unit derived from oceanic arc magmatism. This finding indicates that the subducted oceanic lithosphere of the ?zmir-Ankara-Erzincan branch of the Neotethys Ocean produced oceanic volcanic arcs close to the subduction zone (i.e., the Yerkuyu Unit) and beneath the Sakarya continental microplate (i.e., the Tafano Unit).

The Anatolian peninsula is a key location to study the central portion of the Neotethys Ocean(s) and to understand how its western and eastern branches were connected. One of the lesser known branches of the Mesozoic ocean(s) is preserved in the northern ophiolite suture zone exposed in Turkey, namely, the Intra-Pontide suture zone. It is located between the Sakarya terrane and the Eurasian margin (i.e., Istanbul-Zonguldak terrane) and consists of several metamorphic and non-metamorphic units containing ophiolites produced in supra-subduction settings from the Late Triassic to the Early Cretaceous. Ophiolites preserved in the metamorphic units recorded pervasive deformations and peak metamorphic conditions ranging from blueschist to eclogite facies. In the non-metamorphic units, the complete oceanic crust sequence is preserved in tectonic units or as olistoliths in sedimentary mélanges. Geochemical, structural, metamorphic and geochronological investigations performed on ophiolite-bearing units allowed the formulation of a new geodynamic model of the entire “life” of the Intra-Pontide oceanic basin(s). The reconstruction starts with the opening of the Intra-Pontide oceanic basins during the Late Triassic between the Sakarya and Istanbul-Zonguldak continental microplates and ends with its closure caused by two different subductions events that occurred during the upper Early Jurassic and Middle Jurassic. The continental collision between the Sakarya continental microplate and the Eurasian margin developed from the upper Early Cretaceous to the Palaeocene. The presented reconstruction is an alternative model to explain the complex and articulate geodynamic evolution that characterizes the southern margin of Eurasia during the Mesozoic era. Keywords: Intra-Pontide suture zone, Central Pontides, Northern Turkey, Ophiolites, Neotethys Ocean, Geodynamics

A multidisciplinary approach combining multiscale geological-structural analyses (from field to microscale) and clay mineral transformations (clay mineralogy, illite and chlorite "crystallinity" and b cell dimension (b0) of K-white mica) was adopted to unravel the tectono-metamorphic evolution of low- and very low-grade tectono-metamorphic units from the Intra-Pontide suture zone in northern Turkey. The mineralogical study allowed to better evaluate the structural stacking outlined during the geological mapping, leading to distinguish three tectono-metamorphic units, two in epizone (Daday and Emirkoy units) and one in anchizone (Çifter Unit) metamorphic conditions. The mesostructural and microstructural analyses suggest a polyphase tectonic-metamorphic evolution. The different macroscopic features observed between the two units characterized by the same epizone metamorphism, can be justified by the evidence that these metamorphic conditions were acquired during the last stages of exhumation in the Daday Unit, while they constrained the metamorphic-peak conditions in the Emirkoy Unit. Contemporary analyses and comparison between structural and mineralogical data have thus proven to be a powerful tool to investigate the low-grade and very low-grade metamorphic environments, allowing at the same time to solve the apparent contradictions deriving from the mineralogical study and to significantly improve the detail of the geological mapping in the field.

The Centenary of the 1920 Garfagnana-Lunigiana Earthquake provides the Apuan Alps Geopark with an opportunity to learn from the past to build a safer future

The Intra-Pontide suture zone is the northernmost ophiolite suture zone exposed in the Anatolian peninsula. It consists of several variably deformed and metamorphosed tectonic units derived from the Neo-Tethyan Intra-Pontide oceanic (IPO) basin, and its continental margins that are currently represented by the Istanbul-Zonguldak and the Sakarya terranes. Recent data suggests that the IPO was a wide supra-subduction oceanic basin whose closure began in the uppermost Early Jurassic by a north dipping intra-oceanic subduction that divided the IPO into two different oceanic areas, namely IPO1 and IPO2. The Saka Unit is a small tectonic unit exposed in the eastern portion of the Intra-Pontide suture zone in the Central Pontides, which is interpreted as a tectonic melange produced during the intra-oceanic subduction that led to the closure of IPO1. The unit was affected by polyphase deformation and epidote–amphibolite facies metamorphism peak conditions experienced during the uppermost Middle Jurassic. Metamorphic studies and thermodynamic investigations constrain the peak pressure conditions to T ≈ 650–700 °C and P ≈ 0.9–1.3 GPa. These conditions reveal a ‘hot’ and anomalous geothermal gradient (15–22 °C/km) with respect to those of the other ophiolite-bearing units of the Intra-Pontide suture zone involved in the subduction. This anomalous gradient was herein attributed to the thermal pulse produced by the subduction of the IPO1 mid-oceanic ridge. The final re-equilibration occurred under greenschist facies conditions during the Early Cretaceous exhumation, when the oceanic lithosphere of the IPO was completely consumed and the continental collision between the Istanbul-Zonguldak and Sakarya terranes occurred.

Way-marked trails along the Gothic Line in the Apuan Alps Geopark

At the beginning of 2019, the Apuan Alps UGGp produced a new leaflet that is meant to promote 9 geotrails celebrating the geological and cultural heritage of the Geopark. These geotrails are footpaths with varying travel times (from one hour or less, up to a maximum of one day) and difficulty rating (easy, moderate and difficult). They are suitable for both families with children and experienced hikers and are equipped with explanatory panels. The geotrails' locations are shown in a simplified map that offers visitors a comprehensive geographical awareness by highlighting the main geosites, main access roads and railway stations and other tourist points of interest. The geotrails can be divided according to their main geological and geomorphological meaning. All the described footpaths offer the possibility to discover places full of geology, culture and evocative landscapes in the wild nature of the Apuan Alps.

In northern Turkey, the Intra-Pontide suture zone is represented by an east–west trending belt of deformed and/or metamorphic units located at the boundary between the Istanbul–Zonguldak terrane to the north and the Sakarya terrane to the south. These units can be regarded as issued from the Intra-Pontide domain, whose geodynamic history is still a matter of debate. Along the Akpinar–Arac–Bayramoren geotraverse, located in central Turkey, an ophiolite-bearing melange known as the Arkot Dag Melange, is well-exposed along the Intra-Pontide suture zone. The Arkot Dag Melange plays a key role in the interpretation of the geodynamic history of the Intra-Pontide domain and can be described as a Late Santonian chaotic sedimentary deposit consisting of an up to 1000-m-thick succession of slide-blocks of different sizes and lithologies enclosed in a sedimentary matrix consisting of shales, coarse-grained arenites, pebbly mudstones and pebbly sandstones. The slide-blocks, from a few meters to hectometers in size, are represented by metamorphic rocks (mainly micaschists and gneisses), by ophiolites (peridotites, gabbros, IAT and BABB basalts and cherts) and by sedimentary rocks (cherts, neritic and pelagic limestone, marly limestone and ophiolite-bearing turbidites). The youngest age among the slide-blocks has been provided by the ophiolite-bearing turbidites where a late Coniacian nannofossil assemblage has been found. The cherts have provided a wide range of ages from the Middle Triassic to Late Cretaceous, whereas the fossils found in the limestone indicate Late Jurassic to Early Cretaceous ages. The matrix of the Arkot Dag Melange, even if unaffected by metamorphism, shows deformations represented by multiple meters-thick cataclastic shear zones at the boundaries of the melange slices or inside of them. According to its features, the source area of the Arkot Dag Melange was most likely a continental and oceanic thrust sheet emplaced in the Late Cretaceous onto a continental margin. The data collected from the different slide-blocks suggest that the Intra-Pontide domain was characterised by an oceanic basin opened at the latest in the Early Jurassic. The opening of the Intra-Pontide oceanic basin was followed by the development of a subduction zone with a subsequent opening of suprasubduction oceanic basin in the Middle Jurassic–Early Cretaceous. The convergence in this suprasubduction oceanic basin started at the Early/Late Cretaceous boundary by an obduction process, whereas its final closure can be regarded as Late Paleocene in age.

Since the first discovery of ultrahigh pressure (UHP) rocks 30 years ago in the Western Alps, the mechanisms for exhumation of (U)HP terranes worldwide are still debated. In the western Mediterranean, the presently accepted model of synconvergent exhumation (e.g., the channel-flow model) is in conflict with parts of the geologic record. We synthesize regional geologic data and present alternative exhumation mechanisms that consider the role of divergence within subduction zones. These mechanisms, i.e., (i) the motion of the upper plate away from the trench and (ii) the rollback of the lower plate, are discussed in detail with particular reference to the Cenozoic Adria-Europe plate boundary, and along three different transects (Western Alps, Calabria-Sardinia, and Corsica-Northern Apennines). In the Western Alps, (U)HP rocks were exhumed from the greatest depth at the rear of the accretionary wedge during motion of the upper plate away from the trench. Exhumation was extremely fast, and associated with very low geothermal gradients. In Calabria, HP rocks were exhumed from shallower depths and at lower rates during rollback of the Adriatic plate, with repeated exhumation pulses progressively younging toward the foreland. Both mechanisms were active to create boundary divergence along the Corsica-Northern Apennines transect, where European southeastward subduction was progressively replaced along strike by Adriatic northwestward subduction. The tectonic scenario depicted for the Western Alps trench during Eocene exhumation of (U)HP rocks correlates well with present-day eastern Papua New Guinea, which is presented as a modern analog of the Paleogene Adria-Europe plate boundary.

Catalogo della mostra didattica "L'alluvione del 1996 tra Versilia e Garfagnana: Rains & Ruins in the Apuan Alps"

OBJECTIVE. To describe the occurrence of CRKP infections in a tertiary care hospital and to analyse the allelic profiles of the clinical strains involved and the most frequent carbapenemases. DESIGN. The study analyzed cases of infection due to CRKP in the period 2013-2014. 147 cases of CRKP infection were recorded most of which (82.31%) were in-hospital infections. SETTING. One hospital in northern Italy. METHODS. We retrospectively collected: data on patient characteristics, microbiological characteristics of CRKP. The isolates from 72 of the-hospital cases underwent molecular typing (MLST); in addition, in each isolate, a procedure for the detection of the blaKPC gene was carried out. RESULTS: The in-hospital death rate was 24.0% in 2013 and 37.5% in 2014. However, the difference between these two values did not prove statistically significant (P> .05). Analysis of mortality revealed that bloodstream infections were more frequently associated with death than other infections (CHI2=14.57, P, Journal of Preventive Medicine and Hygiene, Vol 57, No 3 (2016): 2016573

This paper presents the results of multidisciplinary studies performed on the Intra-Pontide suture zone (Central Pontides, Northern Turkey) by an Italian-Turkish team. The investigations started in 2010 thanks to the funds provided by Progetti di Rilevante Interesse Nazionale (prin) project, provided by Italian Ministry of Education, University and Scientific Research (Ministero dell'Istruzione, dell'Università e della Ricerca scientifica, miur), and by Darius Programme, sponsored by a network of oil companies. All the data collected during these researches indicated that the Intra-Pontide suture zone preserves remains of an oceanic basin, known as Intra- Pontide oceanic basin, probably opened in the Middle Triassic. Since Late Jurassic, the basin has experienced a subduction-related tectonics until its final closure in the Middle Paleocene. On the whole, the main results of these researches are the assessment that the Intra-Pontide suture zone really derived from the closure of the Intra-Pontide oceanic basin. This basin represents a paleogeographic element that has played an important role in the geodynamics history of the Eastern Mediterranean area.

This paper describes the main activities and actions that the Apuan Alps Geopark has undertaken for many years with the aim of improving the knowledge of its geological heritage as well as taking advantage of the protection of the environment as a driving force to boost sustainable tourism. These actions were object of an important international recognition, which resulted, in September 2011, in the admission of the Apuan territory to the European and Global Geoparks Network, under the auspices of UNESCO, as a Apuan Alps. Geopark.

Il presente contributo illustra i principali risultati di uno studio, promosso dall'Ente Parco Regionale delle Alpi Apuane nell'ambito del Protocollo d'intesa con l'Istituto di Geoscienze e Georisorse del CNR per lo sviluppo delle conoscenze geologiche e per la tutela e la valorizzazione della geodiversità delle Alpi Apuane, che ha per oggetto l'interpretazione di un blocco di marmo di possibile origine glaciale ubicato in località Rondinella nel Comune di Vagli Sotto.

Il Complesso carsico dell'Antro del Corchia è un geosito/geomorfosito già considerato di interesse scientifico nazionale o mondiale, attraverso un breve e sommario procedimento di valutazione. Il suo valore è qui sottoposto a diversi metodi di valutazione quantitativa, al fine di verificare queste opinioni consolidate e ridurre la loro soggettività. Sono stati usati differenti indicatori tesi alla valutazione non solo del valore scientifico (rarità, rappresentatività, conoscenza, ecc.), ma di altri valori aggiunti (culturale, estetico, ecologico, ecc.) e/o di valore d'uso (accessibilità, servizi, limitazioni, ecc.) e/o di valore di tutela/conservazione (integrità, vulnerabilità, ecc.). I risultati ottenuti da questo geosito/geomorfosito si posizionano al di sopra o all'estremità superiore dell'intervallo di variabilità degli indicatori relativi ad esempi di confronto. Questo approccio conferma i valori distinti e complessivi del Complesso carsico e il suo probabile interesse di livello internazionale in campo scientifico, nonostante i limiti dei metodi di valutazione quantitativa di geositi/geomorfositi.

Editing new hiking and geotourist maps is one of the projects that the Apuan Alps Geopark included among its 2011-2015 objectives after its official entry in the European and Global Geoparks Network, under the auspices of UNESCO. The Hiking and Geotourist Map represents the best tool to familiarize the general public with the geological heritage of the Apuan Alps and thus allowing to appreciate its great scientific and environmental value during trekking activities. The footpaths managed by the Alpine Club of Italy (CAI) have been completely redrawn and geographically referred on the most detailed available topographic base (the Technical Map of the Tuscany Region). The basic geological information is provided by polygons with different colors. The distinction of these areas follows two main parameters: the age of the outcropping rocks (Paleozoic Era and Periods for post-Paleozoic ages) and their basic classification (sedimentary rocks vs. metamorphic rocks). A further geological/geomorphological content is represented by the surveyed geosites. The tourist facilities are also highlighted; a special label is reserved for facilities certified by the Geopark for their eco-friendly choices. The Map was developed within a GIS project and printed at 1:20.000 scale with legends in two languages (Italian and English). The further development of the project will create a dynamic and interactive map available via web that will allow each user to benefit from a wealth of information through the activation of additional hyperlinks.

In the Central Pontides (Northern Turkey), south of Tosya, a tectonic unit consisting of not-metamorphic volcanic rocks and overlying sedimentary succession is exposed inside a fault-bounded elongated block. It is restrained within a wide shear zone, where the Intra-Pontide suture zone, the Sakarya terrane and the Izmir-Ankara-Erzincan suture zone are juxtaposed as result of strike-slip activity of the North Anatolian shear zone. The volcanic rocks are mainly basalts and basaltic andesites (with their pyroclastic equivalents) associated with a volcaniclastic formation made up of breccias and sandstones that are stratigraphically overlain by a Marly-calcareous turbidite formation. The calcareous nannofossil biostratigraphy points to a late Santonian-middle Campanian age (CC17-CC21 Zones) for the sedimentary succession. The geochemistry of the volcanic rocks reveals an active continental margin setting as evidenced by the enrichment in Th and LREE over HFSE, and the Nb-enriched nature of these lavas relative to N-MORB. As highlighted by the performed arenite petrography, the occurrence of continent-derived clastics in the sedimentary succession supports the hypothesis of a continental arc-derived volcanic succession. Alternative geodynamic reconstructions are proposed, where this tectonic unit could represent a slice derived from the northern continental margin of the Intra- Pontide or Izmir-Ankara-Erzincan oceanic basins.

The palaeogeography of Neotethys during its closure is still a matter of debate. This study provides new insights into the Neotethys closure by the discovery in the Intra-Pontide Suture Zone (Turkey) of an accretionary complex that recorded a Late Jurassic ( c . 163 Ma) amphibolite-facies metamorphism. Results are discussed in the framework of the accretionary events that occurred at the southern margin of Laurasia. The resulting picture supports a new model in which the Vardar suture zone, in the Balkans, and the Intra-Pontide Suture Zone, in Anatolia, represent remnants of the same elongate oceanic basin. Supplementary material: Analytical procedures, representative mineral compositions, geothermobarometric estimates, step-heating and in situ 40 Ar− 39 Ar data and backscattered-electron photomicrographs showing the distribution of laser spot ages on rock chips are available at www.geolsoc.org.uk/SUP18759.

The Apuan Alps Geopark has planned and created ApuanGeoLab, an interactive museum aimed to disseminate knowledge about concepts in the Earth Sciences and to improve the understanding of the connection between the local geological evolution and global processes. Along the visit trail every visitor is a "geologist for a day", starting on a journey that provides an explanation of the physical and chemical mechanisms that shaped and modified the planet Earth in geologic time, from global to local, from "Gaia" to "Apua". ApuanGeoLab, opened to the public in May 2013, is located in the village of Equi Terme, in the northern sector of the Apuan Alps Geopark. ApuanGeoLab is therefore a new structure that increases the attractiveness of the Cultural Park of the Equi Terme Caves, an existing network of tourist facilities based on nearby geosites and archeosites.

In the BoyalI area, northern Turkey, the tectonic units of the Istanbul-Zonguldak Terrane and the IntraPontide suture zone are thrust over the deposits at the top of the Sakarya Terrane, known as TaraklI Flysch. It consists of Early Maastrichtian-Middle Paleocene turbidite and mass-gravity deposits, whose source mainly corresponds to the Istanbul-Zonguldak Terrane, and, with a lesser extent, to the IntraPontide suture zone. These deposits were sedimented in a foredeep basin developed during the convergence between Sakarya and Eurasian continental microplates. In the Late Paleocene-Early Eocene time span, the TaraklI Flysch was deformed (D1 phase) during the closure of the foredeep basin. In the Miocene time, the strike-slip tectonics (D2 phase) related to the North-Anatolian fault produced further deformations of the TaraklI Flysch.

È stato intrapreso uno studio geologico-strutturale alla meso e microscala su un blocco di marmo di diverse migliaia di m3 di volume, localizzato in località Rondinella, estendendo le ricerche all'area circostante corrispondente alla zona di Vagli Sopra, in provincia di Lucca. L'obiettivo dello studio è quello di utilizzare metodologie alternative al classico approccio geomorfologico con il fine di apportare un contributo alla discussione sulla natura o meno di masso erratico del blocco studiato, interpretazione che comporta evidenti ricadute sui modelli proposti per il glacialismo apuano. L'analisi geologico-strutturale ha permesso di individuare con ragionevole certezza due possibili aree di derivazione del blocco, a seconda delle quali possono essere ipotizzati diversi processi di messa in posto del masso della Rondinella. In entrambi i casi, l'interpretazione del blocco di marmo come masso erratico, il cui trasporto e messa in posto siano cioè da attribuire esclusivamente all'azione di un ghiacciaio, sembra comunque poco plausibile.

The Ayli Dag ophiolites occur as an independent tectonic unit within the Intra-Pontide suture zone, central-northern Turkey. They crop out, together with the other units of the Intra-Pontide suture zone, at the top of the Late Cretaceous-Middle Paleocene foredeep sediments of the Sakarya Terrane. The Ayli Dag ophiolites sequence include in its lower part a mantle sequence consisting of not less than 2-3 km-thick peridotites, topped by 500-600 m-thick layered gabbros with alternating, dm- to m-thick layers of spinel-bearing dunites, melatroctolites, troctolites, ol-gabbros and leucogabbros. The gabbro sequence is overlain by a sheeted dyke complex, that shows a transition to 100-200 m-thick massive basaltic lava flows followed by 600-800 m-thick massive and pillow lavas and breccias alternating with ophiolite-bearing arenites and cherts. Geochemical evaluation of the mafic lavas and dykes reveals three distinct chemical groups that reflect melt generation within an intra-oceanic subduction system. Among these, the first group shows island-arc tholeiite (IAT)-like features, showing very-depleted characteristics (very high Zr/Nb, low Zr/Y and Nb/Y) ratios coupled with light rare-earth (LREE)-depleted chondrite-normalized patterns. The second group is more akin to back-arc basin basalts (BABB); it displays normal mid-ocean ridge basalt (N-MORB)-like high-field strength element (HFSE) distribution except for depletion in Nb, and flat REE patterns. The third group is somewhat similar to the second one, displaying BABB-like characteristics, but it is more enriched in terms of absolute trace element abundances. The radiolarian cherts sampled from the top of the pillow lavas yielded less-diverse but characteristic radiolarian assemblages indicating the middle Bathonian to early Callovian ages. The Ayli Dag Ophiolite is the first finding of back-arc type oceanic lithosphere in the Intra-Pontide suture zone. Together with previous data obtained from basalts in the mélange from the Intra-Pontide suture zone, this finding represents a proof that an intra-oceanic subduction within the Intra-Pontide oceanic basin occurred in the Middle Jurassic time.