Early Pleistocene marine deposits in southwestern Umbria (Orvieto–Allerona area, Italy) recently revealed the presence of more than forty carbonate conduits distributed over 2 km along the Paglia ...riverbed. In order to investigate their origins, analyses of their mineralogy, δ18O and δ13C stable isotopes, and organic geochemistry were conducted. All the carbonate conduits are made of euhedral microcrystals of dolomite with subordinate quartz, plagioclases, and micas. The stable carbon and oxygen isotope values of the bulk concretionary carbonates range from −0.57 to +4.79‰ (δ13C) and from +1.58 to +4.07‰ (δ18O), respectively. The lack of organic geochemical biomarkers of anaerobic methane oxidation (AOM) and the very low values of extractable organic matter suggest a non-biological origin for the dolomite precipitation. The latter is probably related to the rise of volcanic carbon dioxide due to the incipient Vulsini magmatism recorded in Early Pleistocene marine deposits all around the study site. The spatial distribution of the structures indicates that the upward migration of the CO2 was controlled by the fault system, while the vertical development of the conduits suggests that carbon dioxide degassing occurred, with multiple events. Carbon dioxide was probably stored in pockets within the clayey sediments until the pressure exceeded the eruptive threshold. These structures represent the first documentation of a volcanic carbon dioxide marine seepage event in the Umbria region.
Here we describe the first sauropod skeletal remains from the Italian peninsula that also represent the earliest record of titanosaurs in Southern Europe. Scattered bones, including an almost ...complete anterior caudal vertebra, were found in Cretaceous (Aptian–Albian) marine deposits, some 50 km East of Rome. The vertebra shows a bizarre and perhaps unique orientation of the zygapophyseal articular facets that renders their interpretation problematic. Phylogenetic retrofitting tests support the placement of the Italian titanosaur among basal lithostrotians. Palaeobiogeographic analysis based on the resulting phyletic relationships suggests an Afro-Eurasian route for the ancestors of the Italian titanosaur, a scenario compatible with the palaeogeographic evolution of the Italian microplates during the Cretaceous. Together with previously recorded titanosaurian-like ichnites from a Cenomanian locality in Latium, this new find suggests a quite long emersion for the Apenninic carbonate platform. We suggest that the Italian titanosaur was member of a population that crossed the western Tethys Sea through a “filtering bridge” composed of a chain of ephemeral islands and peninsulae, known as Periadriatic (Adria) carbonate platforms, that connected sporadically Africa and Europe since the Early Cretaceous.
Display omitted
•Referable to Titanosauria gen. et sp. indet., earliest record in southern Europe.•An Aptian–Albian basal titanosaurian with bizarre orientation of the zygapophyseal facets.•Further evidence of Early Cretaceous sporadic connection between Africa and Europe.
The occurrence of lunulite bryozoan assemblages in the Early Pleistocene of western Umbria, central Italy, is documented for the first time. Six species within the genera
Reussirella
,
Cupuladria,
...and
Discoporella
were recovered. Study sections encompass a wide range of marine coastal deposits varying from beachface to offshore, which developed in the area during the Early Pleistocene (Gelasian to Calabrian) and were locally influenced by river supply. Lunulite bryozoans mainly occur in infra- to circalittoral, bioclastic-rich sand to mud sediments deposited in locally vegetated paleoenvironments, characterized by moderate to low energy and ranging from lower shoreface to offshore. Based on grain-size analysis, coupled with evidence from benthic foraminiferan and mollusc associations, a main bathymetric range of 10–60 m can be inferred for lunulite distribution in the area, with a prevalence in the 30–50-m interval and a subordinate presence down to about 120 m. Lunulite growth was here also conditioned by a warm climate and a temporarily high sedimentation rate.
A rich decapod fauna from the Early Pleistocene (late Gelasian-early Calabrian) of Poggio i Sodi quarries (Siena, Tuscany, central Italy) is here reported. Integrated biostratigraphical, ...sedimentological and paleoecological analyses have been carried out, and some paleoenvironmental inferences are also proposed. The studied decapod community is herein assigned to the upper bathyal; several paleoenvironmental factors (cool water conditions at the sea floor, clay soft bottom, nutrients, very low environmental energy and sedimentation rate) influenced and promoted the crustacean settlement.
We report an unusual and rich decapod crustacean assemblage from the early Pliocene (Zanclean), recently collected during the excavations of the “La Serra” quarry, located in La Serra, near San ...Miniato, Pisa (Toscana, central Italy). The studied specimens have been assigned, as follows: Axius sp., Callianassa chalmasiiBrocchi, 1883, and Calliaxina cf. C. punica (de Saint Laurent and Manning, 1982) (infraorder Axiidea de Saint Laurent, 1979); Gebiacantha tuscia Garassino, Pasini, De Angeli and Charbonnier sp. nov. (infraorder Gebiidea de Saint Laurent, 1979); Pagurus alatusFabricius, 1775, and Pagurus sp. (infraorder Anomura MacLeay, 1838); Dromia neogenicaMüller, 1978, Dromia sp., Medorippe cf. M. ampla Garassino, De Angeli, Gallo and Pasini, 2004, Ilia nucleus (Linnaeus, 1758), Ristoria pliocaenica (Ristori, 1891), Pisa armata (Latreille, 1803), Macropodia sp., Maja squinado (Herbst, 1788), Derilambrus angulifrons (Latreille, 1825), Atelecyclus undecimdentatus (Herbst, 1783), Liocarcinus sp., Thalamita italica Garassino, Pasini, De Angeli and Charbonnier sp. nov., Pilumnus cf. P. hirtellus (Linnaeus, 1761), Eriphia cocchiiRistori, 1886, Goneplax rhomboides (Linnaeus, 1758), Goneplax sacciCrema, 1895, (infraorder Brachyura Linnaeus, 1758). Moreover, two specimens have been assigned to callianassideans sensu lato and 13 specimens to indeterminate axiideans. CalliaxinaNgoc-Ho, 2003, GebiacanthaNgoc-Ho, 1989, Ristoria Garassino, Pasini, De Angeli and Charbonnier gen. nov., and Macropodia Leach, 1814, are reported for the first time in the fossil record and the extant Pagurus alatus, Ilia nucleus, Pisa armata, Derilambrus angulifrons, and Pilumnus cf. P. hirtellus, are reported in the fossil record from the Pliocene. Everywhere “La Serra” quarry bio-community is very important, representing one of the richest and most diversified crustacean faunas from the Pliocene reported to date in the Mediterranean basin and worldwide, increasing notably the knowledge on the decapod populations and distribution during the early Pliocene. This community is indicative of a palaeoenvironment of shallow sublittoral water, with sandy-muddy and alternate hard shell bottom, partially covered or in proximity of seagrass, similar to the extant Mediterranean Posidonia beds, mainly inhabited by fossorial and benthonic decapods.
Nous décrivons un riche et exceptionnel assemblage de crustacés décapodes du Pliocène inférieur (Zancléen), récemment récolté durant les travaux de creusement de la carrière « La Serra » localisée à La Serra, près de San Miniato, Pise (Toscane, Italie centrale). Les spécimens étudiés ont été identifiés de la façon suivante : Axius sp., Callianassa chalmasiiBrocchi, 1883, et Calliaxina cf. C. punica (de Saint Laurent et Manning, 1982) (infra-ordre Axiidea de Saint Laurent, 1979) ; Gebiacantha tuscia Garassino, Pasini, De Angeli et Charbonnier sp. nov. (infra-ordre Gebiidea de Saint Laurent, 1979) ; Pagurus alatusFabricius, 1775, et Pagurus sp. (infra-ordre Anomura MacLeay, 1838) ; Dromia neogenicaMüller, 1978, Dromia sp., Medorippe cf. M. ampla Garassino, De Angeli, Gallo et Pasini, 2004, Ilia nucleus (Linnaeus, 1758), Ristoria pliocaenica (Ristori, 1891), Pisa armata (Latreille, 1803), Macropodia sp., Maja squinado (Herbst, 1788), Derilambrus angulifrons (Latreille, 1825), Atelecyclus undecimdentatus (Herbst, 1783), Liocarcinus sp., Thalamita italica Garassino, Pasini, De Angeli et Charbonnier sp. nov., Pilumnus cf. P. hirtellus (Linnaeus, 1761), Eriphia cocchiiRistori, 1886, Goneplax rhomboides (Linnaeus, 1758), Goneplax sacciCrema, 1895, (infra-ordre Brachyura Linnaeus, 1758). De plus, deux spécimens ont été attribués à des callinassidés sensu lato et 13 spécimens à des axiidés indéterminés. CalliaxinaNgoc-Ho, 2003, GebiacanthaNgoc-Ho, 1989, Ristoria Garassino, Pasini, De Angeli et Charbonnier gen. nov., et Macropodia Leach, 1814, sont signalés pour la première fois dans le registre fossile et les actuels Pagurus alatus, Ilia nucleus, Pisa armata, Derilambrus angulifrons, et Pilumnus cf. P. hirtellus sont signalés dans le registre fossile dès le Pliocène. La communauté de la carrière « La Serra » constitue un ensemble très important représentant l’une des faunes de crustacés les plus riches et les plus diversifiées du Pliocène du Bassin méditerranéen et même du monde. Elle augmente considérablement la connaissance des populations de décapodes et leur distribution au cours du Pliocène inférieur. Cette communauté est l’indicateur d’un paléoenvironnement sublittoral peu profond, avec un fond sablo-boueux alternant avec des coquilles dures, partiellement couvert d’un herbier ou très proche d’un herbier. Ce paléoenvironnement est très comparable aux prairies àPosidonia de la Méditerranée actuelle qui sont principalement habitées par des décapodes benthiques et fouisseurs.
La comunità di decapodi del Pliocene inferiore (Zancleano) della cava “La Serra” (San Miniato, Pisa, Toscana, Italia centrale): sedimentologia, sistematica e implicazioni paleo-ambientali. Viene descritta una inusuale e ricca fauna a crostacei decapodi del Pliocene inferiore (Zancleano), recentemente raccolta durante i lavori di scavo industriale della cava “La Serra”, posta in località La Serra presso San Miniato, Pisa (Toscana, Italia centrale). I campioni studiati provengono da un livello di argille sabbiose di spessore limitato (0.50–0.70m) esposto su un fronte di circa 50m lungo la parte sommitale della cava, frammisti a una ricca malacofauna. Le analisi sedimentologiche e lo studio delle macro-microfaune hanno permesso di interpretare la complessa successione stratigrafica trasgressiva, e di ricostruire un modello articolato dell’antico ambiente costiero. In particolare le osservazioni micro-paleontologiche hanno consentito una datazione dei livelli fossiliferi al Pliocene inferiore (Zancleano). I resti dei decapodi sono generalmente conservati come modelli all’interno di concrezioni subnodulari indurite in veri noduli di piccole dimensioni o, più raramente, inglobati nel sedimento. La fauna è indicativa di un ambiente marino sublitorale poco profondo in presenza di fondali sabbioso-fangosi, con aree composte da substrato più solido derivato in prevalenza da accumuli di gusci frammentari di molluschi e, probabilmente, ricoperti da praterie algari simili alle attuali praterie a Posidonia, abitato in prevalenza da decapodi fossatori e bentonici. I decapodi studiati sono stati assegnati a: Axius sp., Callianassa chalmasiiBrocchi, 1883 e Calliaxina cf. C. punica (de Saint Laurent & Manning, 1982) (infraordine Axiidea de Saint Laurent, 1979); Gebiacantha tuscia Garassino, Pasini, De Angeli & Charbonnier sp. nov. (infraordine Gebiidea de Saint Laurent, 1979); Pagurus alatusFabricius, 1775 e Pagurus sp. (infraordine Anomura MacLeay, 1838); Dromia neogenicaMüller, 1978, Dromia sp., Medorippe cf. M. ampla Garassino, De Angeli, Gallo & Pasini, 2004, Ilia nucleus (Linnaeus, 1758), Ristoria pliocaenica (Ristori, 1891), Pisa armata (Latreille, 1803), Macropodia sp., Maja squinado (Herbst, 1788), Derilambrus angulifrons (Latreille, 1825), Atelecyclus undecimdentatus (Herbst, 1783), Liocarcinus sp., Thalamita italica Garassino, Pasini, De Angeli & Charbonnier sp. nov., Pilumnus cf. P. hirtellus (Linnaeus, 1761), Eriphia cocchiiRistori, 1886, Goneplax rhomboides (Linnaeus, 1758) e Goneplax sacciCrema, 1895 (infraordine Brachyura Linnaeus, 1758). Due esemplari sono stati attribuiti a callianassidi sensu lato e tredici a axiidi indeterminati. Prima dello studio carcinologico de “La Serra”, i crostacei decapodi della Toscana erano rappresentati da 14 famiglie, comprendenti 24 generi con 22 specie. Lo studio della ricca associazione a crostacei decapodi de “La Serra” ha permesso di incrementare le conoscenze finora acquisiste. Allo stato attuale si conoscono infatti 16 famiglie che comprendono 19 generi con 22 specie. I dati raccolti da questo studio indicano che più dell’80% dei generi e circa il 75% delle specie precedentemente conosciute nel Pliocene della Toscana sono presenti per la prima volta nello stesso paleoambiente de “La Serra”, rappresentando la più abbondante e diversificata fauna carcinologica del Pliocene inferiore dell’area mediterranea. La grande quantità e la perfetta conservazione degli esemplari raccolti ha inoltre permesso d’individuare e di descrivere il nuovo genere Ristoria Garassino, Pasini, De Angeli & Charbonnier gen. nov. e al tempo stesso di discutere e chiarire la posizione sistematica di Ilia pliocaenica Ristori, 1891. Lo studio della fauna carcinologica de “La Serra” ha inoltre permesso di stabilire che CalliaxinaNgoc-Ho, 2003, GebiacanthaNgoc-Ho, 1989, Ristoria Garassino, Pasini, De Angeli & Charbonnier gen. nov., e Macropodia Leach, 1814 sono segnalati per la prima volta nel record fossile mentre Pagurus alatus, Ilia nucleus, Pisa armata, Derilambrus angulifrons e Pilumnus cf. P. hirtellus sono riportati per la prima volta nel record fossile del Pliocene inferiore. Due specie, già note nel Miocene, Dromia neogenica e Medorippe cf. M. ampla, e tre specie, precedentemente segnalate nel Pleistocene, I. nucleus, P. armata e D. angulifrons, sono aggiunte al record fossile del Pliocene del bacino Mediterraneo. Axius sp., Calliaxina cf. C. punica, P. alatus, D. neogenica, I. nucleus, P. armata, D. angulifrons, Atelecyclus undecimdentatus (Herbst, 1783) e Pilumnus cf. P. hirtellus, sono segnalate per la prima volta nel Pliocene Italiano. Inoltre Axius sp., Calliaxina cf. C. punica, P. alatus, D. neogenica, I. nucleus, P. armata, Maja squinado (Herbst, 1788), D. angulifrons, A. undecimdentatus e Pilumnus cf. P. hirtellus sono segnalate per la prima volta nel Pliocene della Toscana. In conclusione, il particolare ambiente e l’eccezionale bio-diversità della fauna rinvenuta a “La Serra” è estremamente importante in quanto rappresenta una delle più ricche e differenziate associazioni di decapodi sinora note nel Pliocene del bacino Mediterr
This paper presents an overview of the geophysical activities for the seismic microzonation of 138 municipalities belonging to four Italian regions (Abruzzo, Lazio, Marche and Umbria) that were ...severely damaged by the seismic sequence of Central Italy (August 2016–January 2017). This study is the result of a collaborative effort between research Institutions and professional geologists with the support of local Administrations and the Italian Civil Protection Department and sets an unprecedented large-scale example of geophysical investigations supporting detailed seismic microzonation studies. This manuscript presents the methodological approach adopted for the geophysical activities, including the technical protocols and procedures, the best practices, the final products and the results supporting a detailed microzonation study of III level. The first step of the study was the collection and critical review of all available geophysical and geological information for planning the new geophysical surveys (specifically their type and location), in order to assess the subsoil geometry and the seismic characterization of the areas under investigation. Integration with the newly acquired geophysical data allowed the identification of zones with homogeneous local seismic hazard as well as the reference seismo-stratigraphy for each area, defining for each geological unit the ranges of the relevant properties in seismic amplification studies: layering and thicknesses, density, P-wave and S-wave seismic velocity. We also present a few representative case studies illustrating the geophysical investigation for different geomorphological situations. These examples, together with the findings of the entire project, are discussed to point out the strength points and the criticalities, as well as the necessary requirements in the application of geophysical methods to detailed microzonation studies.
PDF
