Rendiconti online della Società Geologica Italiana, 2018
The carbonate succession cropping out in the Upper Aniene
Valley was studied since the last decad... more The carbonate succession cropping out in the Upper Aniene Valley was studied since the last decade of the XIX century. Before, only generic mentions to the fossil content of carbonate rocks were made. Since the year 1890 the interest of geologists for this part of Italy grew up, mostly due to the finding of an abundant rudist fauna from the Monte Affilano quarry (Central Apennines), where a high quality and very versatile lithoid material known as “Subiaco stone” was extracted; the remarkable well preserved rudist bivalves found in the quarry made possible the establishment of the new genus Sabinia and four species. Starting from this locality, the whole Mesozoic carbonate succession was then studied, leading in only a few years to the definition of an almost continue Upper Triassic/Upper Cretaceous succession. Subsequently, between 1920 and 1930, also the lack of Paleogene rocks was noticed, thus completing the typical picture of a Meso-Cenozoic carbonate succession including a wide Paleogenic hiatus; the first geological map of the area was therefore published only in 1939.
Rendiconti online della Società Geologica Italiana, 2018
It is a widely diffused opinion that the knowledge of the geologic features of the Calabrian terr... more It is a widely diffused opinion that the knowledge of the geologic features of the Calabrian territory may be referred to the early XX century; nevertheless, a thorough investigation carried out in the cartographic collection of the ISPRA Library, that preserves the historical heritage of the Geological Survey of Italy, allowed to access and analyze original XIX century maps of undoubted scientific interest. The precursor of all 'modern' geological studies in Calabria was Leopoldo Pilla, who analyzed the relationships between the intrusive units and sedimentary successions in the '30s, soon after followed by the German naturalist Rodolfo A. Philippi. Appended to a handwritten Italian translation of a paper of Philippi we have found some geological sketches of the Calabrian region; despite their uncertain attribution, they most likely represent preparatory drafts for a final publication, and are, to date, the first known geological maps of the region. After the mentioned pioneers, up to the '70s, only few authors dealt with the geology of Calabria, and a surprising finding of our research was the discovery of a map and a document drawn up by S. Giancossi, which was however almost ignored by the scientific community. The interest for the geology of Calabria was renewed in the '70s of the XIX century, first by Gerhard vom Rath and then by Vincenzo Rambotti. Subsequently and until the end of the XIX century, just prior to the publication of the Calabrian sheets of the official cartographic map at 1:100,000 scale of the Geological Survey of Italy, many projects of geological mapping were carried out by several geologists, including Carlo De Stefani, Renato Fucini, Giuseppe Seguenza and, above all, Domenico Lovisato. Between 1878 and 1881 Lovisato, appointed by the Royal Geological Committee, realized a geological map in 32 sheets of Northern Calabria on the 1:50,000 scale, that represents the first geological map of the region conceived in a modern way. Undoubtedly, this work was the milestone for the production of the official cartography, realized since 1895 under the direction of Emilio Cortese. "La Calabria […] merita una visita degli scienziati italiani e stranieri per la sua costituzione geologica vedendo noi laggiù, in quell'estremo lembo di terra continentale riprodotte le nostre Alpi settentrionali di Piemonte e Lombardia, con tali analogie nelle forme litologiche di quelle contrade che sono più varie che nella settentrionale Italia, da confonderne le une colle altre. (Estratto da "Relazione geologica sulla missione in Calabria, da Domenico Lovisato a Felice Giordano", 25 novembre 1880. Archivio Servizio Geologico d'Italia-ISPRA, Faldone 1880-1886). KEY WORDS: Calabria, history of geology, geological mapping. INTRODUZIONE La conoscenza moderna dei caratteri geologici della Calabria si fa risalire tradizionalmente alla fine del XIX secolo, quando venne avviata la realizzazione dei primi fogli della cartografia geologica ufficiale ricadenti nel territorio della regione. Per quanto riguarda il periodo precedente, sebbene con alcune eccezioni (Fabbi et al., 2017), solo qualche sporadico accenno alla geologia calabrese è ben noto alla comunità scientifica. Una ricerca effettuata presso l'Archivio e le Collezioni Cartografiche della Biblioteca ISPRA, che conserva il patrimonio storico del Servizio Geologico d'Italia, ha permesso di recuperare e analizzare materiale documentale e cartografico, edito e inedito, precedente l'attività di rilevamento finalizzato alla pubblicazione della Carta Geologica d'Italia alla scala 1:100.000 del R. Ufficio Geologico. LINEAMENTI GEOLOGICI DELLA CALABRIA La Calabria è una regione dalla geologia estremamente complessa. Essa costituisce una parte dell'Arco Calabro-Peloritano, che si frappone tra la catena appenninica e la catena maghrebide che si sviluppa in Sicilia (Amodio Morelli et al., 1976). La complessità della geologia calabrese è dovuta al fatto che in questa regione affiorano sia gli ultimi contrafforti meridionali della catena appenninica, costituiti essenzialmente da successioni carbonatiche mesozoiche, che unità altrove sconosciute in Italia a sud delle Alpi, quali porzioni di basamento paleozoico costituite da enormi plutoni granitoidi di età carbonifera e da una ricca varietà di rocce di ogni grado metamorfico, riferibili alla deformazione dell'orogene ercinico (Amodio Morelli et al., 1976). Oltre alle unità sopra citate, in Calabria affiorano metamorfiti e ofioliti ascrivibili all'orogenesi alpina (Amodio Morelli et al., 1976), e successioni sedimentarie mesozoiche non metamorfosate deposte sul margine europeo dell'oceano Tetide (Santantonio et al., 2016). A questo va aggiunto un enorme prisma sedimentario neogenico, deposto in bacini legati alla deformazione della catena appenninica, a sua volta coperto da un potente ciclo quaternario sia marino che continentale (Muto et al., 2014). In Calabria, quindi, si riscontrano evidenze di almeno tre fasi orogenetiche e affiorano rocce di età compresa tra il Paleozoico inferiore e l'Olocene. Il rapido sollevamento recente della regione è causa di una morfologia fortemente
Rendiconti Online della Società Geologica Italiana, 2019
We describe the first evidence of sclerobiont bryozoans found
loose in the pelagic Maiolica Fm. o... more We describe the first evidence of sclerobiont bryozoans found loose in the pelagic Maiolica Fm. of the Umbria-Marche Basin (Monte Acuto Massif, Northern Apennines, Italy). The material is represented by three small sub-circular colonies with tube-shaped zooecia radially developing from the centre. These characters are not enough for generic or specific classification, consequently, these cyclostomes have been only identified as belonging to the Suborder Tubuliporina. Calpionellid assemblages allow to constrain the bryozoan-bearing rock sample to the early Berriasian. The occurrence of isolated bryozoans in the Maiolica Fm. enriches the knowledge about the fauna of this unit in pure basinal settings, composed by radiolarians, calpionellids, dinoflagellate cysts and rare macrofossils (ammonites and aptychi), including very rare benthic organisms (gastropods, brachiopods and bivalves). Up to date, no sclerobiont organisms in ‘normal’ pelagic Maiolica facies were known, due to the lack of suitable substrates to be colonised. Encrustation of a planktonic or nektonic hard-shelled organism seems the most parsimonious hypothesis based on our material.
This paper presents the results of a geological mapping project across the northern portion of th... more 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 postorogenic 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.
The sedimentary successions exposed in northeast Calabria document the Jurassic–Early Cretaceous ... more The sedimentary successions exposed in northeast Calabria document the Jurassic–Early Cretaceous tectonic– sedimentary evolution of a former segment of the European–Iberian continental margin. They are juxtaposed today to units representing the deformation of the African and Adriatic plates margins as a product of Apenninic crustal shortening. A complex pattern of unconformities reveals a multi-stage tectonic evolution during the Early Jurassic, which affected the facies and geometries of siliciclastic and carbonate successions deposited in syn-and post-rift environments ranging from fluvial to deep marine. Late Sinemurian/Early Pliensbachian normal faulting resulted in exposure of the Hercynian basement at the sea-floor, which was onlapped by marine basin-fill units. Shallow-water carbonate aprons and reefs developed in response to the production of new accommodation space, fringing the newborn islands which represent structural highs made of Paleozoic crystalline and metamor-phic rock. Their drowning and fragmentation in the Toarcian led to the development of thin caps of Rosso Ammonitico facies. Coeval to these deposits, a thick (N 1 km) hemipelagic/siliciclastic succession was sedimented in neighboring hanging wall basins, which would ultimately merge with the structural high successions. Footwall blocks of the Early Jurassic rift, made of Paleozoic basement and basin-margin border faults with their onlapping basin-fill formations, are found today at the hanging wall of Miocene thrusts, overlying younger (Middle/Late Jurassic to Late Paleogene) folded basinal sediments. This paper makes use of selected case examples to describe the richly diverse set of features, ranging from paleontology to sedimentology, to structural geology, which are associated with the field identification of basin-margin unconformities. Our data provide key constraints for restoring the pre-orogenic architecture of a continental margin facing a branch of the Liguria–Piedmont ocean in the Western Tethys, and for estimating displacements and slip rates along synsedimentary faults.
Re-sedimented deposits characterize different stratigraphical intervals in the pelagic succession... more Re-sedimented deposits characterize different stratigraphical intervals in the pelagic successions of the Umbria-Marche-Sabina Domain (Central and Northern Apennines, Italy). Three stratigraphic sections of the Maiolica and Marne a Fucoidi Formations, characterized by breccias and calcarenites embedded in pelagic sediments, were sampled across the Mt. Primo area (Umbria-Marche Ridge, Northern Apennines). Facies analysis indicates a gravity-driven origin for the clastic levels, interpreted as debris-flows, or turbidity flows. The massive lensoid-to-tabular levels are composed of loose shallow-water benthic material, sourced from an unknown carbonate platform, associated with: i) lithoclasts made of Lower Jurassic and Lower Cretaceous shallow-water carbonates; ii) Jurassic mudstones and wackestones referable to the pelagic succession; iii) calpionellid/radiolarian-rich soft pebbles (Maiolica-type facies). The compositional features of the studied detrital deposits imply submarine exposure and dismantling of portions of the stratigraphic succession older than the Barremian/Aptian, which had to be buried in the late Early Cretaceous. Such evidence led us to refer the investigated clastic event to an extensional tectonic phase. Our interpretation well fits with data coming from different geological settings of Italy, strongly suggesting the occurrence of a widespread extensional phase in the late Early Cretaceous.
The Montagna dei Fiori has received attention from geologists over the past decades because of bo... more The Montagna dei Fiori has received attention from geologists over the past decades because of both its Jurassic stratigraphy and its complex present-day structure. The latter is the result of multiple phases of deformation, from the Early Jurassic, during the opening of the Tethyan Ocean, to Neogene evolution of the Apennines fold-and-thrust belt. In this paper, we present a new stratigraphic interpretation of the Jurassic palaeogeography, based on a new geological mapping project in the area. Using this new stratigraphy, we constructed two forward models, using a combination of different fault/fold interactions, in order to unravel the kinematic evolution of the Montagna dei Fiori fault-related fold. The first model was constructed manually using the fault-bend and fault-propagation theories from an initial configuration which included previous extensional features, whereas the second model was constructed using the software 2DMove (Midland Valley) using the fault-bend and trishear fault-propagation folding theories and starting from a layer-cake stratigraphy. Both forward models involved the same main steps and provided a reasonable geological simulation of the geometry of the Montagna dei Fiori structure.
Scientific studies dealing with the intimate relationship between
geology and First World War app... more Scientific studies dealing with the intimate relationship between geology and First World War appeared in Italy already during the conflict, or in the first decade after the end of hostilities. In this note we have focused on two leading Italian geologists, Enrico Fossa-Mancini and Federico Sacco which dealt with the possible use and importance of geology in military operations, from territorial defense, to detection of optimal areas for large troop movements. Despite the similarity of the subject, and the not excessive time interval between the scripts, the works of the two authors show a dramatically different approach and point of arrival. The analysis by Fossa-Mancini is more objective, detached and pragmatic, being carried out with a ‘clear mind’ after the end of the conflict. His study is polished and purposeful, identifying the actions required in time of peace to ‘geologically’ prepare a nation to a potential conflict. Differently, the analysis by Sacco does not take into account the real situation highlighted by Fossa-Mancini (e.g. the complete unpreparedness of the high Italians command in terms of military use of geology), and uses his writing to exalt the primacy of the Italian army in the consideration of geology in military conflicts. In Sacco, geology and the study of the Italian natural territory it is expertly used as a justification and reason for the war, which it is perceived by the author as necessary, of liberation and redemption.
“At war with the eagles” represents the first national event organized by the History of Geoscien... more “At war with the eagles” represents the first national event organized by the History of Geosciences Section, established in 2012 by the Italian Geological Society in order to recover and endorse the national geological culture. A century after the Italian intervention in the First World War, the meeting focuses on the role of geologists and cartographers on the alpine fronts, before, during and after hostilities. This short note briefly describes the history and purposes of the Geoitaliani project that aims to revitalize the importance of geology in the past as a basis for the future development of our Nation and the human journey on Planet Earth.
In the NE Simbruini Mountains, the “Brecce della Renga Fm.” is a clastic unit documenting sedimen... more In the NE Simbruini Mountains, the “Brecce della Renga Fm.” is a clastic unit documenting sedimentation controlled by late Miocene extensional tectonics.The unit has been subdivided into three lithofacies and six sublithofacies, based on the arenite/rudite/pelite ratio. Massive and coarser (up to megablock size) intervals are interpreted as rockfall deposits (likely induced by earthquakes) at the toe of steep submarine escarpments. By contrast, finer levels are interpreted as having been sedimented through avalanching and turbidity flows in more distal settings, and are partly lateral to basinal hemipelagites and siliciclastic turbidites. Pelite lenses, found at various stratigraphic levels, are the result of ponded sedimentation along the clastic margin. Calcareous nannofossils analyses have been performed for age determinations on 60 fossiliferous samples, which were collected in each sublithofacies of the “Brecce della Renga Fm.”. The unit ranges from early Tortonian (MNN8b) to e...
Cretaceous successions of the Latium-Abruzzi Carbonate Platform in the northern Simbruini Mts. (C... more Cretaceous successions of the Latium-Abruzzi Carbonate Platform in the northern Simbruini Mts. (Central Italy) are characterized by the abundance of rudist-bearing facies and easy accessibility of outcrops. An Upper Cretaceous composite stratigraphic section (∼ 20 m thick) has been reconstructed, to study inner platform deposits outcropping in the area of Marsia through integrated benthic foraminifers and rudists biostratigraphy, coupled with facies analysis. This preliminary study provides interesting data and is a starting point for considerations about some difficulties on studying Upper Cretaceous successions in the L-A Platform. The lower portion is a thin-bedded dolostone/limestone interval (wacke-to-packstone) containing an oligotypic fauna with Discorbidae sp. a, Discorbis cf. turonicus, miliolidae and ostracoda; this pass upwards to decimetrethick wacke-to-packstones with abundant rudist fragments and Nezzazatinella cf. aegyptiaca, that suggests a late Turonian p.p. age. Upwards, metre-thick rudist float-to-rudstones occur, with faunal assemblages dominated by Radiolites trigeri, occurring both in monospecific levels or associated with Durania arnaudi and Biradiolites angulosus, interbedded to fenestral-bindstone with Thaumatoporella parvovesiculifera and minor bioclastic pack-grainstone with black-pebbles. Moncharmontia cf. compressa and rotalidae are present within the floatstone, while bindstone is characterized by Nummuloculina cf. irregularis. Also the recently introduced new species Spirosigmoilina rajkae, described in the upper Turonian of the L-A Platform, occurs. The following interval is a thick-bedded float-to-rudstone with Biradiolites martellii monospecific association. The uppermost part of the succession is a floatstone/rudstone interval, whose rudist association is composed by Sauvagesia sp., Biradiolites martellii and Lapeirousella samnitica and rare large hippuritidae (Vaccinites sp.). Also sparse bioclastic lenses with nerineids are present. The associated microfacies is composed by Dicyclina schlumbergeri, Moncharmontia compressa, Nezzazatinella picardi, Pseudocyclammina sphaeroidea, Nummoloculina sp., Rotorbinella scarsellai. On the basis of paleontological data, this interval is Santonian. Other definitely Santonian deposits, observed in the area, are characterized by similar faunal assemblages, with also Accordiella conica, Eponides hemisphaericus, Murgeina apula and Reticulinella fleuryi. In conclusion the succession can be referred to the "Nezzazatinella cf. aegyptiaca and Nummoloculina cf. irregularis" and "Accordiella conica and Rotorbinella scarsellai" biozones, encompassing the late Turonian-Santonian interval. It is remarkable a certain difficulty on identifying the Coniacian stage, as is in most of the regional literature, probably due to its limited thickness (no more than 10 m estimated in our section) and the scarcity of unequivocal markers (the FO of Accordiella conica and Rotorbinella scarsellai mark the Coniacian base, but their LO is within the lower Campanian, and are in addition not always found in rudist-bearing facies). According to recent biostratigraphical schemes for the Central Apennines, the common foraminifer Nezzazatinella picardi (present in our section) is a marker of Santonian (albeit in literature it is commonly recognized since the Albian). A review of this taxon, and a more precise definition of its stratigraphic range and that of the similar N. aegyptiaca, could be in our opinion, a useful tool for the discrimination of Coniacian and Santonian stages in inner platform facies, characterized by oligotypic associations.
ABSTRACT This paper presents the results of a geological mapping project across the Mt. Primo rid... more ABSTRACT 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 Resedimented calcarenites and hybrid arenites are commonly found interbedded with variou... more ABSTRACT Resedimented calcarenites and hybrid arenites are commonly found interbedded with various Upper Miocene terrigenous units (hemipelagic marls, “brecce della Renga fm.”, and siliciclastic turbidites) across the Simbruini Mts. and neighbouring areas of Central Apennines. Their distribution provides evidence for a complex, and rapidly evolving, paleogeography across a region that was experiencing the transition from foreland to accretionary wedge conditions during the Tortonian and Messinian. The bio-sedimentological features of the calcarenites indicate deposition through gravity flows (turbidity currents) sourced by areas of active benthic, heterozoan-type carbonate production, locally lying at photic depth. Thin-section analysis of >130 samples revealed that the resedimented levels are mainly composed by bioclastic calcarenites, with fragments of bivalves, echinoids, bryozoans, balanids, benthic foraminifera, anellids and red algae, along with subordinate planktonic foraminifera. The calcareous turbidites in the hemipelagic marls (“argilloso-marnosa unit”) are characterized by the presence of Heterostegina sp., and their main source area was probably lying east, on the undeformed foreland. In contrast, evidence from field mapping, their common association with cretaceous and miocene carbonate lithoclasts, and the age of the encasing units, all suggest that the calcarenites in the “brecce della Renga fm.” and in the siliciclastic turbidites (“complesso torbiditico altomiocenico laziale-abruzzese”) could most likely have a different source. The presence of a carbonate ridge, corresponding today to the NW sector of the Simbruini range, bordered by normal faults exposing the cretaceous substrate is proven by mappable paleoescarpment tracts onlapped by clastic and hemipelagic deposits. This ridge could have fed surrounding deeper areas with a mixture of lithoclasts and loose bioclastic material, produced through erosion of exposed bedrock coupled with export of sediment that was being produced topping and fringing the footwall blocks and their marginal downsteps. Carbonate production was apparently able to survive for a limited time in small productive areas until the early Messinian, shedding sediment into the siliciclastic foredeep.
Rendiconti online della Società Geologica Italiana, 2018
The carbonate succession cropping out in the Upper Aniene
Valley was studied since the last decad... more The carbonate succession cropping out in the Upper Aniene Valley was studied since the last decade of the XIX century. Before, only generic mentions to the fossil content of carbonate rocks were made. Since the year 1890 the interest of geologists for this part of Italy grew up, mostly due to the finding of an abundant rudist fauna from the Monte Affilano quarry (Central Apennines), where a high quality and very versatile lithoid material known as “Subiaco stone” was extracted; the remarkable well preserved rudist bivalves found in the quarry made possible the establishment of the new genus Sabinia and four species. Starting from this locality, the whole Mesozoic carbonate succession was then studied, leading in only a few years to the definition of an almost continue Upper Triassic/Upper Cretaceous succession. Subsequently, between 1920 and 1930, also the lack of Paleogene rocks was noticed, thus completing the typical picture of a Meso-Cenozoic carbonate succession including a wide Paleogenic hiatus; the first geological map of the area was therefore published only in 1939.
Rendiconti online della Società Geologica Italiana, 2018
It is a widely diffused opinion that the knowledge of the geologic features of the Calabrian terr... more It is a widely diffused opinion that the knowledge of the geologic features of the Calabrian territory may be referred to the early XX century; nevertheless, a thorough investigation carried out in the cartographic collection of the ISPRA Library, that preserves the historical heritage of the Geological Survey of Italy, allowed to access and analyze original XIX century maps of undoubted scientific interest. The precursor of all 'modern' geological studies in Calabria was Leopoldo Pilla, who analyzed the relationships between the intrusive units and sedimentary successions in the '30s, soon after followed by the German naturalist Rodolfo A. Philippi. Appended to a handwritten Italian translation of a paper of Philippi we have found some geological sketches of the Calabrian region; despite their uncertain attribution, they most likely represent preparatory drafts for a final publication, and are, to date, the first known geological maps of the region. After the mentioned pioneers, up to the '70s, only few authors dealt with the geology of Calabria, and a surprising finding of our research was the discovery of a map and a document drawn up by S. Giancossi, which was however almost ignored by the scientific community. The interest for the geology of Calabria was renewed in the '70s of the XIX century, first by Gerhard vom Rath and then by Vincenzo Rambotti. Subsequently and until the end of the XIX century, just prior to the publication of the Calabrian sheets of the official cartographic map at 1:100,000 scale of the Geological Survey of Italy, many projects of geological mapping were carried out by several geologists, including Carlo De Stefani, Renato Fucini, Giuseppe Seguenza and, above all, Domenico Lovisato. Between 1878 and 1881 Lovisato, appointed by the Royal Geological Committee, realized a geological map in 32 sheets of Northern Calabria on the 1:50,000 scale, that represents the first geological map of the region conceived in a modern way. Undoubtedly, this work was the milestone for the production of the official cartography, realized since 1895 under the direction of Emilio Cortese. "La Calabria […] merita una visita degli scienziati italiani e stranieri per la sua costituzione geologica vedendo noi laggiù, in quell'estremo lembo di terra continentale riprodotte le nostre Alpi settentrionali di Piemonte e Lombardia, con tali analogie nelle forme litologiche di quelle contrade che sono più varie che nella settentrionale Italia, da confonderne le une colle altre. (Estratto da "Relazione geologica sulla missione in Calabria, da Domenico Lovisato a Felice Giordano", 25 novembre 1880. Archivio Servizio Geologico d'Italia-ISPRA, Faldone 1880-1886). KEY WORDS: Calabria, history of geology, geological mapping. INTRODUZIONE La conoscenza moderna dei caratteri geologici della Calabria si fa risalire tradizionalmente alla fine del XIX secolo, quando venne avviata la realizzazione dei primi fogli della cartografia geologica ufficiale ricadenti nel territorio della regione. Per quanto riguarda il periodo precedente, sebbene con alcune eccezioni (Fabbi et al., 2017), solo qualche sporadico accenno alla geologia calabrese è ben noto alla comunità scientifica. Una ricerca effettuata presso l'Archivio e le Collezioni Cartografiche della Biblioteca ISPRA, che conserva il patrimonio storico del Servizio Geologico d'Italia, ha permesso di recuperare e analizzare materiale documentale e cartografico, edito e inedito, precedente l'attività di rilevamento finalizzato alla pubblicazione della Carta Geologica d'Italia alla scala 1:100.000 del R. Ufficio Geologico. LINEAMENTI GEOLOGICI DELLA CALABRIA La Calabria è una regione dalla geologia estremamente complessa. Essa costituisce una parte dell'Arco Calabro-Peloritano, che si frappone tra la catena appenninica e la catena maghrebide che si sviluppa in Sicilia (Amodio Morelli et al., 1976). La complessità della geologia calabrese è dovuta al fatto che in questa regione affiorano sia gli ultimi contrafforti meridionali della catena appenninica, costituiti essenzialmente da successioni carbonatiche mesozoiche, che unità altrove sconosciute in Italia a sud delle Alpi, quali porzioni di basamento paleozoico costituite da enormi plutoni granitoidi di età carbonifera e da una ricca varietà di rocce di ogni grado metamorfico, riferibili alla deformazione dell'orogene ercinico (Amodio Morelli et al., 1976). Oltre alle unità sopra citate, in Calabria affiorano metamorfiti e ofioliti ascrivibili all'orogenesi alpina (Amodio Morelli et al., 1976), e successioni sedimentarie mesozoiche non metamorfosate deposte sul margine europeo dell'oceano Tetide (Santantonio et al., 2016). A questo va aggiunto un enorme prisma sedimentario neogenico, deposto in bacini legati alla deformazione della catena appenninica, a sua volta coperto da un potente ciclo quaternario sia marino che continentale (Muto et al., 2014). In Calabria, quindi, si riscontrano evidenze di almeno tre fasi orogenetiche e affiorano rocce di età compresa tra il Paleozoico inferiore e l'Olocene. Il rapido sollevamento recente della regione è causa di una morfologia fortemente
Rendiconti Online della Società Geologica Italiana, 2019
We describe the first evidence of sclerobiont bryozoans found
loose in the pelagic Maiolica Fm. o... more We describe the first evidence of sclerobiont bryozoans found loose in the pelagic Maiolica Fm. of the Umbria-Marche Basin (Monte Acuto Massif, Northern Apennines, Italy). The material is represented by three small sub-circular colonies with tube-shaped zooecia radially developing from the centre. These characters are not enough for generic or specific classification, consequently, these cyclostomes have been only identified as belonging to the Suborder Tubuliporina. Calpionellid assemblages allow to constrain the bryozoan-bearing rock sample to the early Berriasian. The occurrence of isolated bryozoans in the Maiolica Fm. enriches the knowledge about the fauna of this unit in pure basinal settings, composed by radiolarians, calpionellids, dinoflagellate cysts and rare macrofossils (ammonites and aptychi), including very rare benthic organisms (gastropods, brachiopods and bivalves). Up to date, no sclerobiont organisms in ‘normal’ pelagic Maiolica facies were known, due to the lack of suitable substrates to be colonised. Encrustation of a planktonic or nektonic hard-shelled organism seems the most parsimonious hypothesis based on our material.
This paper presents the results of a geological mapping project across the northern portion of th... more 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 postorogenic 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.
The sedimentary successions exposed in northeast Calabria document the Jurassic–Early Cretaceous ... more The sedimentary successions exposed in northeast Calabria document the Jurassic–Early Cretaceous tectonic– sedimentary evolution of a former segment of the European–Iberian continental margin. They are juxtaposed today to units representing the deformation of the African and Adriatic plates margins as a product of Apenninic crustal shortening. A complex pattern of unconformities reveals a multi-stage tectonic evolution during the Early Jurassic, which affected the facies and geometries of siliciclastic and carbonate successions deposited in syn-and post-rift environments ranging from fluvial to deep marine. Late Sinemurian/Early Pliensbachian normal faulting resulted in exposure of the Hercynian basement at the sea-floor, which was onlapped by marine basin-fill units. Shallow-water carbonate aprons and reefs developed in response to the production of new accommodation space, fringing the newborn islands which represent structural highs made of Paleozoic crystalline and metamor-phic rock. Their drowning and fragmentation in the Toarcian led to the development of thin caps of Rosso Ammonitico facies. Coeval to these deposits, a thick (N 1 km) hemipelagic/siliciclastic succession was sedimented in neighboring hanging wall basins, which would ultimately merge with the structural high successions. Footwall blocks of the Early Jurassic rift, made of Paleozoic basement and basin-margin border faults with their onlapping basin-fill formations, are found today at the hanging wall of Miocene thrusts, overlying younger (Middle/Late Jurassic to Late Paleogene) folded basinal sediments. This paper makes use of selected case examples to describe the richly diverse set of features, ranging from paleontology to sedimentology, to structural geology, which are associated with the field identification of basin-margin unconformities. Our data provide key constraints for restoring the pre-orogenic architecture of a continental margin facing a branch of the Liguria–Piedmont ocean in the Western Tethys, and for estimating displacements and slip rates along synsedimentary faults.
Re-sedimented deposits characterize different stratigraphical intervals in the pelagic succession... more Re-sedimented deposits characterize different stratigraphical intervals in the pelagic successions of the Umbria-Marche-Sabina Domain (Central and Northern Apennines, Italy). Three stratigraphic sections of the Maiolica and Marne a Fucoidi Formations, characterized by breccias and calcarenites embedded in pelagic sediments, were sampled across the Mt. Primo area (Umbria-Marche Ridge, Northern Apennines). Facies analysis indicates a gravity-driven origin for the clastic levels, interpreted as debris-flows, or turbidity flows. The massive lensoid-to-tabular levels are composed of loose shallow-water benthic material, sourced from an unknown carbonate platform, associated with: i) lithoclasts made of Lower Jurassic and Lower Cretaceous shallow-water carbonates; ii) Jurassic mudstones and wackestones referable to the pelagic succession; iii) calpionellid/radiolarian-rich soft pebbles (Maiolica-type facies). The compositional features of the studied detrital deposits imply submarine exposure and dismantling of portions of the stratigraphic succession older than the Barremian/Aptian, which had to be buried in the late Early Cretaceous. Such evidence led us to refer the investigated clastic event to an extensional tectonic phase. Our interpretation well fits with data coming from different geological settings of Italy, strongly suggesting the occurrence of a widespread extensional phase in the late Early Cretaceous.
The Montagna dei Fiori has received attention from geologists over the past decades because of bo... more The Montagna dei Fiori has received attention from geologists over the past decades because of both its Jurassic stratigraphy and its complex present-day structure. The latter is the result of multiple phases of deformation, from the Early Jurassic, during the opening of the Tethyan Ocean, to Neogene evolution of the Apennines fold-and-thrust belt. In this paper, we present a new stratigraphic interpretation of the Jurassic palaeogeography, based on a new geological mapping project in the area. Using this new stratigraphy, we constructed two forward models, using a combination of different fault/fold interactions, in order to unravel the kinematic evolution of the Montagna dei Fiori fault-related fold. The first model was constructed manually using the fault-bend and fault-propagation theories from an initial configuration which included previous extensional features, whereas the second model was constructed using the software 2DMove (Midland Valley) using the fault-bend and trishear fault-propagation folding theories and starting from a layer-cake stratigraphy. Both forward models involved the same main steps and provided a reasonable geological simulation of the geometry of the Montagna dei Fiori structure.
Scientific studies dealing with the intimate relationship between
geology and First World War app... more Scientific studies dealing with the intimate relationship between geology and First World War appeared in Italy already during the conflict, or in the first decade after the end of hostilities. In this note we have focused on two leading Italian geologists, Enrico Fossa-Mancini and Federico Sacco which dealt with the possible use and importance of geology in military operations, from territorial defense, to detection of optimal areas for large troop movements. Despite the similarity of the subject, and the not excessive time interval between the scripts, the works of the two authors show a dramatically different approach and point of arrival. The analysis by Fossa-Mancini is more objective, detached and pragmatic, being carried out with a ‘clear mind’ after the end of the conflict. His study is polished and purposeful, identifying the actions required in time of peace to ‘geologically’ prepare a nation to a potential conflict. Differently, the analysis by Sacco does not take into account the real situation highlighted by Fossa-Mancini (e.g. the complete unpreparedness of the high Italians command in terms of military use of geology), and uses his writing to exalt the primacy of the Italian army in the consideration of geology in military conflicts. In Sacco, geology and the study of the Italian natural territory it is expertly used as a justification and reason for the war, which it is perceived by the author as necessary, of liberation and redemption.
“At war with the eagles” represents the first national event organized by the History of Geoscien... more “At war with the eagles” represents the first national event organized by the History of Geosciences Section, established in 2012 by the Italian Geological Society in order to recover and endorse the national geological culture. A century after the Italian intervention in the First World War, the meeting focuses on the role of geologists and cartographers on the alpine fronts, before, during and after hostilities. This short note briefly describes the history and purposes of the Geoitaliani project that aims to revitalize the importance of geology in the past as a basis for the future development of our Nation and the human journey on Planet Earth.
In the NE Simbruini Mountains, the “Brecce della Renga Fm.” is a clastic unit documenting sedimen... more In the NE Simbruini Mountains, the “Brecce della Renga Fm.” is a clastic unit documenting sedimentation controlled by late Miocene extensional tectonics.The unit has been subdivided into three lithofacies and six sublithofacies, based on the arenite/rudite/pelite ratio. Massive and coarser (up to megablock size) intervals are interpreted as rockfall deposits (likely induced by earthquakes) at the toe of steep submarine escarpments. By contrast, finer levels are interpreted as having been sedimented through avalanching and turbidity flows in more distal settings, and are partly lateral to basinal hemipelagites and siliciclastic turbidites. Pelite lenses, found at various stratigraphic levels, are the result of ponded sedimentation along the clastic margin. Calcareous nannofossils analyses have been performed for age determinations on 60 fossiliferous samples, which were collected in each sublithofacies of the “Brecce della Renga Fm.”. The unit ranges from early Tortonian (MNN8b) to e...
Cretaceous successions of the Latium-Abruzzi Carbonate Platform in the northern Simbruini Mts. (C... more Cretaceous successions of the Latium-Abruzzi Carbonate Platform in the northern Simbruini Mts. (Central Italy) are characterized by the abundance of rudist-bearing facies and easy accessibility of outcrops. An Upper Cretaceous composite stratigraphic section (∼ 20 m thick) has been reconstructed, to study inner platform deposits outcropping in the area of Marsia through integrated benthic foraminifers and rudists biostratigraphy, coupled with facies analysis. This preliminary study provides interesting data and is a starting point for considerations about some difficulties on studying Upper Cretaceous successions in the L-A Platform. The lower portion is a thin-bedded dolostone/limestone interval (wacke-to-packstone) containing an oligotypic fauna with Discorbidae sp. a, Discorbis cf. turonicus, miliolidae and ostracoda; this pass upwards to decimetrethick wacke-to-packstones with abundant rudist fragments and Nezzazatinella cf. aegyptiaca, that suggests a late Turonian p.p. age. Upwards, metre-thick rudist float-to-rudstones occur, with faunal assemblages dominated by Radiolites trigeri, occurring both in monospecific levels or associated with Durania arnaudi and Biradiolites angulosus, interbedded to fenestral-bindstone with Thaumatoporella parvovesiculifera and minor bioclastic pack-grainstone with black-pebbles. Moncharmontia cf. compressa and rotalidae are present within the floatstone, while bindstone is characterized by Nummuloculina cf. irregularis. Also the recently introduced new species Spirosigmoilina rajkae, described in the upper Turonian of the L-A Platform, occurs. The following interval is a thick-bedded float-to-rudstone with Biradiolites martellii monospecific association. The uppermost part of the succession is a floatstone/rudstone interval, whose rudist association is composed by Sauvagesia sp., Biradiolites martellii and Lapeirousella samnitica and rare large hippuritidae (Vaccinites sp.). Also sparse bioclastic lenses with nerineids are present. The associated microfacies is composed by Dicyclina schlumbergeri, Moncharmontia compressa, Nezzazatinella picardi, Pseudocyclammina sphaeroidea, Nummoloculina sp., Rotorbinella scarsellai. On the basis of paleontological data, this interval is Santonian. Other definitely Santonian deposits, observed in the area, are characterized by similar faunal assemblages, with also Accordiella conica, Eponides hemisphaericus, Murgeina apula and Reticulinella fleuryi. In conclusion the succession can be referred to the "Nezzazatinella cf. aegyptiaca and Nummoloculina cf. irregularis" and "Accordiella conica and Rotorbinella scarsellai" biozones, encompassing the late Turonian-Santonian interval. It is remarkable a certain difficulty on identifying the Coniacian stage, as is in most of the regional literature, probably due to its limited thickness (no more than 10 m estimated in our section) and the scarcity of unequivocal markers (the FO of Accordiella conica and Rotorbinella scarsellai mark the Coniacian base, but their LO is within the lower Campanian, and are in addition not always found in rudist-bearing facies). According to recent biostratigraphical schemes for the Central Apennines, the common foraminifer Nezzazatinella picardi (present in our section) is a marker of Santonian (albeit in literature it is commonly recognized since the Albian). A review of this taxon, and a more precise definition of its stratigraphic range and that of the similar N. aegyptiaca, could be in our opinion, a useful tool for the discrimination of Coniacian and Santonian stages in inner platform facies, characterized by oligotypic associations.
ABSTRACT This paper presents the results of a geological mapping project across the Mt. Primo rid... more ABSTRACT 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 Resedimented calcarenites and hybrid arenites are commonly found interbedded with variou... more ABSTRACT Resedimented calcarenites and hybrid arenites are commonly found interbedded with various Upper Miocene terrigenous units (hemipelagic marls, “brecce della Renga fm.”, and siliciclastic turbidites) across the Simbruini Mts. and neighbouring areas of Central Apennines. Their distribution provides evidence for a complex, and rapidly evolving, paleogeography across a region that was experiencing the transition from foreland to accretionary wedge conditions during the Tortonian and Messinian. The bio-sedimentological features of the calcarenites indicate deposition through gravity flows (turbidity currents) sourced by areas of active benthic, heterozoan-type carbonate production, locally lying at photic depth. Thin-section analysis of >130 samples revealed that the resedimented levels are mainly composed by bioclastic calcarenites, with fragments of bivalves, echinoids, bryozoans, balanids, benthic foraminifera, anellids and red algae, along with subordinate planktonic foraminifera. The calcareous turbidites in the hemipelagic marls (“argilloso-marnosa unit”) are characterized by the presence of Heterostegina sp., and their main source area was probably lying east, on the undeformed foreland. In contrast, evidence from field mapping, their common association with cretaceous and miocene carbonate lithoclasts, and the age of the encasing units, all suggest that the calcarenites in the “brecce della Renga fm.” and in the siliciclastic turbidites (“complesso torbiditico altomiocenico laziale-abruzzese”) could most likely have a different source. The presence of a carbonate ridge, corresponding today to the NW sector of the Simbruini range, bordered by normal faults exposing the cretaceous substrate is proven by mappable paleoescarpment tracts onlapped by clastic and hemipelagic deposits. This ridge could have fed surrounding deeper areas with a mixture of lithoclasts and loose bioclastic material, produced through erosion of exposed bedrock coupled with export of sediment that was being produced topping and fringing the footwall blocks and their marginal downsteps. Carbonate production was apparently able to survive for a limited time in small productive areas until the early Messinian, shedding sediment into the siliciclastic foredeep.
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Papers by Simone Fabbi
Valley was studied since the last decade of the XIX century. Before,
only generic mentions to the fossil content of carbonate rocks were
made. Since the year 1890 the interest of geologists for this part of
Italy grew up, mostly due to the finding of an abundant rudist fauna
from the Monte Affilano quarry (Central Apennines), where a high
quality and very versatile lithoid material known as “Subiaco stone”
was extracted; the remarkable well preserved rudist bivalves found in
the quarry made possible the establishment of the new genus Sabinia
and four species. Starting from this locality, the whole Mesozoic
carbonate succession was then studied, leading in only a few years to
the definition of an almost continue Upper Triassic/Upper Cretaceous
succession. Subsequently, between 1920 and 1930, also the lack of
Paleogene rocks was noticed, thus completing the typical picture of
a Meso-Cenozoic carbonate succession including a wide Paleogenic
hiatus; the first geological map of the area was therefore published
only in 1939.
loose in the pelagic Maiolica Fm. of the Umbria-Marche Basin (Monte
Acuto Massif, Northern Apennines, Italy). The material is represented
by three small sub-circular colonies with tube-shaped zooecia radially
developing from the centre. These characters are not enough for
generic or specific classification, consequently, these cyclostomes
have been only identified as belonging to the Suborder Tubuliporina.
Calpionellid assemblages allow to constrain the bryozoan-bearing rock
sample to the early Berriasian. The occurrence of isolated bryozoans
in the Maiolica Fm. enriches the knowledge about the fauna of this
unit in pure basinal settings, composed by radiolarians, calpionellids,
dinoflagellate cysts and rare macrofossils (ammonites and aptychi),
including very rare benthic organisms (gastropods, brachiopods and
bivalves). Up to date, no sclerobiont organisms in ‘normal’ pelagic
Maiolica facies were known, due to the lack of suitable substrates to
be colonised. Encrustation of a planktonic or nektonic hard-shelled
organism seems the most parsimonious hypothesis based on our
material.
geology and First World War appeared in Italy already during the
conflict, or in the first decade after the end of hostilities. In this note we
have focused on two leading Italian geologists, Enrico Fossa-Mancini
and Federico Sacco which dealt with the possible use and importance of
geology in military operations, from territorial defense, to detection of
optimal areas for large troop movements. Despite the similarity of the
subject, and the not excessive time interval between the scripts, the
works of the two authors show a dramatically different approach and
point of arrival. The analysis by Fossa-Mancini is more objective,
detached and pragmatic, being carried out with a ‘clear mind’ after the
end of the conflict. His study is polished and purposeful, identifying the
actions required in time of peace to ‘geologically’ prepare a nation to a
potential conflict. Differently, the analysis by Sacco does not take into
account the real situation highlighted by Fossa-Mancini (e.g. the
complete unpreparedness of the high Italians command in terms of
military use of geology), and uses his writing to exalt the primacy of the
Italian army in the consideration of geology in military conflicts. In
Sacco, geology and the study of the Italian natural territory it is expertly
used as a justification and reason for the war, which it is perceived by
the author as necessary, of liberation and redemption.
Valley was studied since the last decade of the XIX century. Before,
only generic mentions to the fossil content of carbonate rocks were
made. Since the year 1890 the interest of geologists for this part of
Italy grew up, mostly due to the finding of an abundant rudist fauna
from the Monte Affilano quarry (Central Apennines), where a high
quality and very versatile lithoid material known as “Subiaco stone”
was extracted; the remarkable well preserved rudist bivalves found in
the quarry made possible the establishment of the new genus Sabinia
and four species. Starting from this locality, the whole Mesozoic
carbonate succession was then studied, leading in only a few years to
the definition of an almost continue Upper Triassic/Upper Cretaceous
succession. Subsequently, between 1920 and 1930, also the lack of
Paleogene rocks was noticed, thus completing the typical picture of
a Meso-Cenozoic carbonate succession including a wide Paleogenic
hiatus; the first geological map of the area was therefore published
only in 1939.
loose in the pelagic Maiolica Fm. of the Umbria-Marche Basin (Monte
Acuto Massif, Northern Apennines, Italy). The material is represented
by three small sub-circular colonies with tube-shaped zooecia radially
developing from the centre. These characters are not enough for
generic or specific classification, consequently, these cyclostomes
have been only identified as belonging to the Suborder Tubuliporina.
Calpionellid assemblages allow to constrain the bryozoan-bearing rock
sample to the early Berriasian. The occurrence of isolated bryozoans
in the Maiolica Fm. enriches the knowledge about the fauna of this
unit in pure basinal settings, composed by radiolarians, calpionellids,
dinoflagellate cysts and rare macrofossils (ammonites and aptychi),
including very rare benthic organisms (gastropods, brachiopods and
bivalves). Up to date, no sclerobiont organisms in ‘normal’ pelagic
Maiolica facies were known, due to the lack of suitable substrates to
be colonised. Encrustation of a planktonic or nektonic hard-shelled
organism seems the most parsimonious hypothesis based on our
material.
geology and First World War appeared in Italy already during the
conflict, or in the first decade after the end of hostilities. In this note we
have focused on two leading Italian geologists, Enrico Fossa-Mancini
and Federico Sacco which dealt with the possible use and importance of
geology in military operations, from territorial defense, to detection of
optimal areas for large troop movements. Despite the similarity of the
subject, and the not excessive time interval between the scripts, the
works of the two authors show a dramatically different approach and
point of arrival. The analysis by Fossa-Mancini is more objective,
detached and pragmatic, being carried out with a ‘clear mind’ after the
end of the conflict. His study is polished and purposeful, identifying the
actions required in time of peace to ‘geologically’ prepare a nation to a
potential conflict. Differently, the analysis by Sacco does not take into
account the real situation highlighted by Fossa-Mancini (e.g. the
complete unpreparedness of the high Italians command in terms of
military use of geology), and uses his writing to exalt the primacy of the
Italian army in the consideration of geology in military conflicts. In
Sacco, geology and the study of the Italian natural territory it is expertly
used as a justification and reason for the war, which it is perceived by
the author as necessary, of liberation and redemption.