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The San Potito area in central Apennines (Italy), enclosed within the Latium‐Abruzzi carbonate platform, exposes anomalously pelagic carbonates filling an intraplatform basin formed during Jurassic rifting. Oriented obliquely to the regional NW‐SE trend of Cenozoic thrusts and extensional faults, the basin's eastern boundary fault system, striking N‐S, played a pivotal role in structuring orogenic and post‐orogenic features. Large tracts of the fault experienced double reactivation: positive inversion during Miocene shortening, and negative during post‐orogenic extension. Double reactivation is evidenced by older‐on‐younger extensional contacts, and by the change in orientation of thrusts and recent extensional faults from NW‐SE to NNW‐SSE, the latter being consistent with the trend of Jurassic rift‐related structures of the area. This structural interplay highlights the importance of Jurassic faults and their ability in forcing the structural trends, by surviving across multiple deformation stages, even controlling active extensional seismicity. [ABSTRACT FROM AUTHOR]

During the sampling of a stratigraphic section along the shore of the Fiastra Lake (Carg Project - Sheet 313 “Camerino” of the Geological Map of Italy at 1:50 000 scale), a small rock boulder with partially exposed bony material was discovered at the base of a small cliff at the northern termination of the Sibillini Mts. In this area, the classical facies of Umbria-Marche stratigraphic succession are well-exposed. The Oligocene-Miocene portion of the succession is represented by the ~200 m-thick Scaglia Cinerea Formation, passing upwards to the ~100 m-thick Bisciaro Formation. The microfossil assemblage has allowed the specimen to be constrained to the lower Burdigalian. The skeletal remains were examined using a CT-SCAN, a non-invasive method that has proven to be highly performing. The analysis revealed some articulated vertebrae, deformed by lithostatic compaction, which are attributed to a shark of the order Lamniformes. Subsequently, the vertebrae were digitally isolated, extracted from the surrounding matrix, and rendered into three-dimensional prints. Through digital retro-deformation, the body length of the lamniform shark was estimated to be approximately 4 metres. Further considerations on the vertebrae allowed us to infer that the studied shark had similarities to either Isurus oxyrinchus Rafinesque, 1810 or Carcharodon carcharias Linnaeus, 1758. The development of a dead-fall microbial community likely facilitated the preservation of the vertebrae. The studied specimen represents the first occurrence of a lamniform shark in the Lower Miocene of the Umbria-Marche Domain and represents one of the very rare recorded occurrences of lamniforms from the Lower Miocene of Italy [ABSTRACT FROM AUTHOR]

Between the years 1913 to 1914 the De Filippi Expedition, led by the Italian explorer and mountaineer Filippo De Filippi (1869–1938), traversed the Himalayan Range from Kashmir to Baltistan and Xinjiang. Exploring mostly unknown territories, traveling more than 2000 kilometers, and equipped with advanced instruments for geodetic and meteorological measurements, the expedition members surveyed, mapped and collected rocks and fossils including from the remote Aksai Chin region. After almost two years, the expedition returned to Italy, however, publication of the findings was delayed due to the outbreak of the First World War. The fossil material and syntheses of the geology and stratigraphy of the area represented unique documents on this sector of Western Tibet, with the Cretaceous Period being documented by the expedition for the first time in the whole Trans-Himalayan Range. The Aksai Chin region remains poorly explored even today, and the De Filippi collection which is housed in the Natural History Museum of the University of Florence now represents one of the few records available for reconstructing the stratigraphy of the area. It constitutes a valuable resource regarding the history of the scientific exploration and understanding of the geology and paleontology of the region, providing a unique window into a very remote and fascinating part of the world. [ABSTRACT FROM AUTHOR]

Mem Soc Geol Ital. 1972; 11: 309-341 11 Innamorati G, Santantonio M. Evidence for extended Hercynian basement and a preserved Jurassic basin-margin tract in Northern Calabria (Southern Italy): the Longobucco Basin. The stratigraphic succession of the Longobucco Basin, exposed along the northeastern slopes of the Sila Mountains in northern Calabria, documents the evolution of a portion of the European/Iberian continental margin of the Tethys which is today part of the so-called Calabria-Peloritani Terrane. 2020; 139: 30-53. 10.3301/IJG.2019.16 19 Santantonio M, Muraro C. Bottom currents on a pelagic carbonate platform: mounds and sediment drifts in the Jurassic succession of the Sciacca Plateau, Western Sicily. [Extracted from the article]

"Classic" field mapping in sedimentary successions, where lithostratigraphy, biostratigraphy and sedimentology meet, still has potential for producing answers to long‐standing problems in basin analysis. In the Northern Apennines of Italy, constraints on the slip rates of Early Jurassic rift faults, related to the embryonic separation of Eurasia and Gondwana, are provided by sedimentology and ammonite biostratigraphy, coupled with the field mapping of exposed tracts of the submarine escarpments and of the clinoform slopes which bordered carbonate footwall blocks. Slip rates of 600–1,000 m/Myr are here computed for Tethyan rift faults, producing >1 km of palaeostructural relief in ~2 million years (earliest Sinemurian: Bucklandi p.p. – Semicostatum p.p. zones). [ABSTRACT FROM AUTHOR]

The Mt Nerone area hosts a Jurassic-Cretaceous Pelagic Carbonate Platform (PCP)-basin succession in the Umbria-Marche Domain (Central Italy). Despite being studied thoroughly on sedimentological and geological aspects, wide-spectrum palaeocological studies are currently missing for this peculiar setting. While several studies on the invertebrate fauna of PCP system are available, the vertebrate fauna remained for a long time mostly unknown. Recently a renewed interest has been directed to vertebrate remains of the region. To date, an articulated dentition and some other tooth fragments of hybodont sharks and neoginglymodian actinopterygians have been described from the Jurassic of the Mt Nerone area. These taxa indicate the existence of diverse durophagous ecological niches available for durophagous fauna in the PCP system, linked to the abundant hard-shelled invertebrate fauna inhabiting the structural highs. In the present contribution we report and describe remains of neoselachians Synechodontiformes from five localities of the Mt Nerone area. The new material, represented by several isolated teeth and referred to as Sphenodus spp., testifies an additional trophic level for the Jurassic palaeoecology in the Umbria-Marche Domain, throwing new light on the peculiar PCP-basin ecosystem. [ABSTRACT FROM AUTHOR]

The upper Miocene dominantly terrigenous succession cropping out at Monte San Fabrizio (Simbruini Mts.) shows peculiar, previously unreported bio‐sedimentological features, which bring fresh elements in a regional palaeogeographic/palaeotectonic key. Overlying the regional foredeep succession, an array of different lithofacies either form mappable outcrops or occur as clasts, remarkably not referable to any stratigraphic units already known in the Central Apennines. These lithologies, which include coral‐bearing siliciclastic sediments, mixed carbonate/siliciclastic deposits with benthic macrofaunas, rhodalgal facies, and conglomerates, essentially made of Mesozoic pelagic lithoclasts, are here grouped in a comprehensive informal unit, called Monte San Fabrizio Unit (MSFU). The most striking feature of the MSFU is a coralgal facies characterized by the occurrence of zooxanthellate (z) corals (Porites and Siderastrea crenulata). While the age of these deposits is not directly determinable due to the lack of biostratigraphic markers, their composition and field relationships clearly place their origin within a late‐orogenic setting: only the uplift, subaerial exposure, and erosion of large portions of the pre‐orogenic stratigraphy, also belonging to different geological domains, and subsequent sediment transport by rivers, can account for the heterogeneous composition of the conglomerates. Their sedimentological characters (i.e., shape and size of the clasts) suggest reworking of the pebbles in a shore environment. A shallow marine photic environment is confirmed by the presence of z‐corals, red algae, and abundant macrofauna. The occurrence of Porites and Siderastrea crenulata represents the first occurrence of corals subsequent to the drowning of the bryozoan limestone carbonate factory, being the youngest occurrence of corals in the Central Apennines and the first ever post‐Burdigalian z‐corals described in the region. This also constrains the age of the MSFU as early–middle (pre‐evaporitic) Messinian, due to the almost total demise of z‐corals known in the Mediterranean in response to the Messinian Salinity Crisis. In conclusion, sedimentology, palaeobiology, and field geology all point to a shallow‐water environment, close to a shoreline, for the MSFU. This unit can be interpreted as representing the vestiges of an ephemeral depositional environment, such as a small wedge‐top basin, an evidence that this portion of the Apennine chain was already structured in the early–middle Messinian. [ABSTRACT FROM AUTHOR]

Here we describe a number of articulated teeth of a hybodont shark from Upper Jurassic deposits of the Monte Nerone Pelagic Carbonate Platform, in the Umbria‐Marche‐Sabina Palaeogeographic Domain (Northern Apennines, Central Italy). The material has been referred to as Asteracanthus cf. A. magnus, a quite well‐known taxon already reported from Middle to Upper Jurassic deposits of Europe. Teeth indicate an extreme crushing feeding behaviour, suggesting as putative prey both infaunal and epifaunal hard‐shelled invertebrates dwelling the sea‐floor, such as large bivalves, brachiopods, gastropods as well as vagile crustaceans. The finding represents, to date, the first formal report of hybodont shark in the Umbria‐Marche‐Sabina Domain, throwing further light on the ecology within Pelagic Carbonate Platform settings, and on the occurrence of Asteracanthus in the Late Jurassic of the Western Tethys. [ABSTRACT FROM AUTHOR]

This paper presents the results of a geological mapping project across the eastern Simbruini Mts. and the higher Roveto Valley (Central Apennines). The study area belongs to the Latium-Abruzzi Domain, which is characterized by a Cretaceous and Miocene carbonate platform succession followed by a thick upper Miocene terrigenous succession. A unique feature of the study area is the existence of a thick clastic unit, the 'brecce della Renga fm.'; this unit was produced by the dismantling of the margins of a large pre-orogenic extensional structural high, which rose within the foredeep basin starting in the early Tortonian. Following the Messinian-Pliocene Apennine chain building phase, the area was subjected to post-orogenic Quaternary extension, related to the opening of the Tyrrhenian sea. A geological map on the 1:20,000 scale illustrates the main stratigraphic and structural features of the area. [ABSTRACT FROM AUTHOR]

This paper presents the results of a geological mapping project across the northern portion of the Simbruini Mts. (Latium-Abruzzi Domain – Central Apennines), where a thick Cretaceous and Miocene carbonate succession, followed by a thick upper Miocene terrigenous foredeep succession, is exposed. The terrigenous succession also includes a peculiar lithoclastic unit (‘brecce della Renga fm.’), whose sedimentation is linked to pre-orogenic (Tortonian-Messinian) extensional tectonics. The study area experienced late Messinian-early Pliocene compression, which is the Apennine chain building phase, followed by Quaternary post-orogenic extension, related to the opening of the Tyrrhenian basin. A geological map, at 1:20,000 scale, illustrates the main stratigraphic and structural features of the area. [ABSTRACT FROM AUTHOR]

This paper presents the results of a geological mapping project across the Mt. Primo ridge and neighbouring areas (Umbria-Marche Domain – Northern Apennines), where a thick Meso-Cenozoic carbonate succession is exposed. A geological map on the 1:15,000 scale, illustrates the main stratigraphic, paleogeographic and structural features of the area. The geometries of Jurassic stratigraphic units, were mainly controlled by the complex submarine topography resulting from an Early Jurassic extensional phase. The three-dimensional distribution of Jurassic rocks in turn conditioned the structural evolution of this part of the Apennines during the chain building phase. [ABSTRACT FROM AUTHOR]

In the Central Apennines, a Tertiary-Present eastward-vergent fold and thrust belt, thrusting mainly occurred in-sequence, cutting across a Mesozoic to Early Neogene succession, deposited in rifted (Early Jurassic) to passive continental margin, to foredeep (late Miocene) conditions. However, the Simbruini Mts were characterized by the occurrence of regional out-of-sequence thrusts (the Vallepietra-Filettino-Monte Ortara thrust fault) and ofTertiary prethrusting normal faults, associated with the deposition of thick breccia deposits (Brecce della Renga, Tortonian-early Messinian). A direct link between these two features is here proposed. Evidence for a prethrusting normal faulting origin for the Brecce della Renga is amply discussed. Although evidence for subduction-related normal faulting is growing in the Apennines literature, nowhere in the region are known extensional systems so vast and their syn-tectonic deposits so thick as in the Simbruini area. We propose that the Simbruini prethrusting normal faults were subduction related, i.e., they developed in the foreland due to anomalous bending of the lithosphere subducting in Late Tertiary time under the Apennines in the Simbruini Mts area. The associated breccia deposits were subsequently deformed during the development of the Simbruini Mts thrust front. We speculate that the prethrusting normal faults allowed the penetration of fluids within the subducting crust and possibly also in the mantle, weakening this part of the subducting plate. As a consequence, the weaker plate was anomalously down-bent, leading to a subcritical state of the Apennines wedge. The regional scale out-of-sequence thrust faults developed in order to bring the Apennines wedge back to the critical state. [ABSTRACT FROM AUTHOR]

The microscale mechanisms of hydrocarbons movement along faults and fault zones, the potential carriers of hydrocarbons toward the productive geological traps, remain largely unknown. The majority of previous studies inferred the hydraulic behavior of faults with respect to hydrocarbon movements without providing meso and microstructural observations from faults permeated by hydrocarbons. To fill this gap, we document meso-structures together with the first fossil microstructural portraits of hydrocarbon flow and pathways along two hydrocarbon-bearing carbonate-hosted normal faults exposed in the central Apennines, Italy. In particular, we show that hydrocarbons cyclically move within tectonically active carbonate normal faults possibly during interseismic and coseismic phases of the seismic cycle. Channelized structures, injection features, and clast-cortex grains suggest the occurrence of transient and localized pulses of pressurized hydrocarbons during coseismic slip. In particular, clast-cortex grains are very similar to microstructures that develop along fault planes for slip velocities between 0.0001 and 1 m/s. Patches of hydrocarbon-bearing breccias/cataclasites with lobate and irregular boundaries, crackle breccias filled by hydrocarbons, and hydrocarbons arrested against hydrocarbon-free discrete fault planes suggest hydrocarbon flow during the interseismic phases with hydrocarbon (over)pressure dissipation after coseismic phases. Fault permeability is created during the coseismic phase and hydrocarbons penetrate the most permeable and uncemented uncohesive fault rocks within the damage zone and arrest against and/or within low-permeability and cemented fault cores. Results are consistent with previous numerical simulations on hydrocarbon movements along faults and time-lapse seismic-reflection imaging, suggesting that the movement of hydrocarbon occurs during interseismic periods within tectonically active faults and along permeable zones cyclically created by seismic activity. Results from this paper are crucial for modelling the hydraulic behavior of carbonate fault damage zone, which have progressively gained popularity as targets of hydrocarbon exploration and production and for CO 2 or H storage. • Hydrocarbon movement along carbonate normal fault is strongly heterogeneous. • Hydrocarbons permeate fault rocks based on local permeability. • Hydrocarbons move during coseismic and interseismic phases. • Transient and local pressurized hydrocarbons can occur during the coseismic phase. [ABSTRACT FROM AUTHOR]

The reconstruction of the hydrocarbon migration and entrapment history is fundamental for reducing risks and identifying traps and migration pathways during oil exploration and exploitation in fold-and-thrust belts, which host 14% of the world's discovered oil reserves. Within fold-and thrust belts, faults and folds have fundamental roles in controlling hydrocarbon migration, entrapment, and/or leakage. Past studies have mainly focused on the role of syn-orogenic thrusts, tear faults, and folds in controlling hydrocarbon migration and entrapment. On the contrary, little attention has been dedicated to the role of normal faults in hydrocarbon remobilization during the post-orogenic extension. We combine field and subsurface data with geological evidence from the Ripi oil field, central Apennines (Italy), and propose a conceptual model for hydrocarbon remobilization along post-orogenic normal faults and potential entrapment within shallow reservoirs. Results show that post-orogenic normal faults promoted up-dip hydrocarbon remobilization from oil traps generated during fold-and-thrust belt development. Where pre-orogenic deposits are still covered by syn-orogenic deposits, hydrocarbons moved up-dip along post-orogenic normal faults and impregnated high-porosity sandstone lenses, generating discontinuous and heavy oil reservoirs. On the contrary, where syn-orogenic deposits were eroded in response to orogenic uplift, hydrocarbons leaked at the Earth's surface. Results from this study can be applied to reduce risks during hydrocarbon exploration and appraisal in similar tectonic settings, such as Hellenides and Carpathian fold-and-thrust belts, as well as the southern Apennines of Italy, where the Tempa Rossa and Monte Alpi oil fields, two of the largest onshore oil fields in Western Europe, were discovered in the last decades. [Display omitted] • Post-orogenic extension controlled hydrocarbon remobilization from deep traps. • Hydrocarbons migrated up-dip along post-orogenic normal faults. • Remobilized hydrocarbons entrapped into high-porosity sandstones. • Where seal was eroded, hydrocarbons leaked to the Earth's surface. • Heavy oil is expected in reservoirs charged by post-orogenic normal faults. [ABSTRACT FROM AUTHOR]