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Carnets Geol., Article, vol. 26, no. 15 Federica Mulè, Simone Casati, Alice Pieri, Marco Merella, Andrea Di Cencio, Giovanni Bianucci & Alberto Collareta.- A sea of pufferfishes: New tetraodontid fossils from the Italian Pliocene shed light on an ongoing Mediterranean bioinvasion.- We report on new finds of pufferfish (Tetraodontiformes: Tetraodontidae) beak-like jaws from well-constrained stratal packages at seven Pliocene localities in Tuscany (central Italy). Although these specimens cannot be identified confidently below the family level, their broad distribution and abundance suggest that pufferfishes were established components of the Mediterranean ecosystems under the warm-water conditions that characterised most of the Pliocene Epoch. As some Pliocene intervals are regarded as robust analogues for near-future climate scenarios, our Tuscan fossils provide a deep-time perspective supporting the idea that continued warming may once again promote the invasion and expansion of tetraodontids and other thermophilic vertebrates in the region - a process already underway as the ongoing 'tropicalization' and 'Lessepsian invasion' drive a dramatic surge in Mediterranean pufferfish diversity and abundance.- DOI: https://doi.org/10.2110/carnets.2026.2615 Carnets Geol., Article, vol. 26, no. 14 Serge Ferry, Georges Truc & Jacques Brulhet.- Recent overdeepening of the middle Ouvèze riverbed (SE France) provides new data about the Pliocene infilling of the middle Rhône valley ria network.- Over 3.5 km south of Roaix village, the middle Ouvèze riverbed has undergone an incision of 5-9 m into its substratum since 1995. The local nesting of the river and erosion of its banks reveals a more complex geometry of exposed Pliocene deposits than previously recognised. The Pliocene stratigraphic succession includes, at the base of the classical Blue Marls, a prograding-aggrading stack of more or less nested, sigmoidal sandstone-marlstone cycles, each comprising an erosive sandstone wedge followed by a draping aggrading marlstone. Sedimentary features suggest that the main depositional mechanism for sandstone was high-velocity hyperpycnal bottom currents linked to river floods updip. These findings are presented in the context of the ria network of the Middle Rhône valley, including mostly unpublished data from the Andra (French Agency for Nuclear Waste Disposal) exploratory works in the lower Cèze valley in the 1990s. The combined data fail to support the idea of a so-called "Zanclean Deluge" during the reflooding of the Mediterranean basin after the Messinian salinity crisis.- DOI: https://doi.org/10.2110/carnets.2026.2614 Carnets Geol., Article, vol. 26, no. 13 Nicolae Trif.- On the first occurrence of Anoxypristis (Pristidae, Elasmobranchii) in the Paleogene of Romania and southeastern Europe.- This study provides the first record of the genus Anoxypristis in Romania and in the whole of southeastern Europe based on two isolated rostral spines discovered in Priabonian deposits of the Transylvanian Basin. Assessment of the validity of previously described Paleogene species of Pristidae emphasizes the need for more rigorous taxonomic criteria based on more than isolated rostral spines. The paleoecological implications of the Romanian Anoxypristis specimens, considering the habitat preferences of the extant species and the depositional environments represented by the fossiliferous strata, point to a coastal or estuarine setting.- DOI: https://doi.org/10.2110/carnets.2026.2613 Carnets Geol., Article, vol. 26, no. 12 Carles Ferràndez-Cañadell, Paula Granero & Telm Bover-Arnal.- Upper Eocene-Oligocene larger Foraminifera from the westernmost Tethys (Prebetic Range, SE Iberia). Revision of Austrotrillina and Risananeiza.- The study of upper Eocene-Oligocene larger foraminiferal assemblages in two sections of the Prebetic Range in south-eastern Iberia (Ibi and La Font Roja sections) revealed a rich diversity, including species previously known only from the Central Tethys, such as the Eocene Neorhipidionina cf. spiralis, and the Oligocene Pfendericonus globulus, Austrotrillina howchini, Idalina pignattii, and Archaias sp., as well as endemic forms such as Peneroplis peramplus, Spirolinella emmae, and Borelis sp. 1. The continuous record of Austrotrillina (Rupelian-Chattian) and Risananeiza (upper Chattian) showed evolutionary trends and allowed for a systematic revision. Austrotrillina asmariensis, A. striata, and A. brunni are considered morphotypes of a single species, A. striata, evolving anagenetically from the lower Rupelian A. paucialveolata, which originated from the Eocene A. eocaenica. The two known species of Risananeiza, R. crassaparies and R. pustulosa, were identified for the first time within the same stratigraphic section. They represent successive stages of an anagenetic species throughout the upper Chattian. The biostratigraphic results provide an improved characterization of Shallow Benthic zones SB 21 to 23 in the westernmost Tethys and allow the subdivision of SB 23 (upper Chattian) into two sub-biozones, 23A and 23B, based on the stratigraphic ranges of miogypsinids (Miogypsinella spp., Postmiogypsinella intermedia) and Risananeiza. The Priabonian-Chattian Neorotalia burdigalensis also exhibits evolutionary trends with potential biostratigraphic relevance. Overall, the biostratigraphic data obtained indicate diachronous, parallel evolution and extinction in several genera, improving our understanding of diversity patterns and migration pathways in Oligocene larger Foraminifera.- DOI: https://doi.org/10.2110/carnets.2026.2612 Geologica Acta, vol. 23, no. 13, 48 p. Casas J.M., Díez-Montes A., Pujol-Solà N., Beranoaguirre A., Proenza J.A., SÁnchez-García T., Álvaro J.J. & Murphy J.B. (2025).- From the Upper Ordovician unconformity to the core-mantle boundary: A review of the Ordovician events in the Canigò massif, Pyrenees.- We present a review of the stratigraphical, structural, geochemical, isotopic and geochronological data that document Ordovician events in the Canigò massif, eastern Pyrenees. Voluminous felsic magmatism, 15-20my in duration, occurred in the Mid to Late Ordovician, in two magmatic pulses that produced several laccolithic bodies, up to ca. 2000m in thickness, which became the protoliths of the various lithologies of the Canigò gneisses. There is also evidence of coeval basalt (now metabasites) with E-MORB affinities. Mid Ordovician uplift and erosion produced an Upper Ordovician (Sardic) unconformity. Synchronous extensional faults built propagation cleavage-free folds affecting a pre-Upper Ordovician succession and caused the erosion of up to 1500m of the underlying Cambrian-Lower Ordovician succession. Early Late Ordovician synsedimentary normal faults produced significant thickness variations in the Upper Ordovician successions. Compiled data match the Ordovician evolution described in Sardinia, Mouthoumet and Montagne Noire (Occitan Domain), but differs from the evolution of neighbouring areas, such as the Iberian, Armorican and Bohemian massifs, where thermal doming and magmatism developed earlier, in Furongian-Early Ordovician times, linked to the Toledanian unconformity. In the study area, uplift, erosion and extensional tectonics argue for a lithospheric uplift coeval with the development of felsic and basaltic (with E-MORB affinities) magmatism, and strongly suggests Mid to Late Ordovician plume activity beneath this segment of NW Gondwanan. The proposed plume would be one of a cluster of plumes impacting the Gondwana periphery that probably migrated inwards into Gondwana. Plume activity may be related to an early Palaeozoic superplume event, that contributed to the birth and development of the Rheic Ocean throughout the Gondwana margin breakup. Geologica Acta, vol. 23, no. 14, 15 p. Corradini C., Corriga M.G., Pondrelli M., Spalletta C., Zocchi C. & Corradetti A. (2025).- Record of a sea level drop in the lower Mississippian limestones near Passo di Monte Croce Carnico (Carnic Alps, Italy).- The lower Carboniferous succession of the Carnic Alps represents the best-preserved example of such stratigraphic interval within the Alps, thus providing crucial insights for paleogeographic and paleoclimatic reconstructions. This research focuses on the combined biostratigraphic and sedimentological analyses of a stratigraphic section near Passo di Monte Croce Carnico (central Carnic Alps). The presence of two polygonal sedimentary structure-bearing levels suggests a sea level drop. Conodont biostratigraphy places these events within the lower part of the Gnathodus interregnum, correlating with the latest Tournaisian. These data, combined with insights from coeval sedimentary records within the Carnic Alps and from other basins worldwide, indicate that higher-frequency sea-level fluctuations, superimposed on an overall regressive trend, influenced the late Tournaisian evolution of the Carnic Basin. Geologica Acta, vol. 23, no. 15, 16 p. Mancini, A., Brandano, M., Gaglianone, G., Mannetta, D. & Ferràndez-Cañadell, C. (2025).- Coralgal buildup in a mixed carbonate-siliciclastic succession of the upper Eocene Sant Martí Xic Formation (Orís, Vic, SE Ebro Basin, Spain).- Coralgal buildups from the mixed carbonate siliciclastic succession of the upper Eocene Sant Martí Xic Formation (Orís, Vic, SE Ebro Basin, Spain) were studied. During the upper Eocene, the sedimentation in the Orís area was strongly influenced by global and local factors associated with the evolution of the Ebro Basin. The stratigraphic series in Orís shows first a transgressive sedimentary sequence characterized by floatstone to rudstone limestone with Discocyclina and Nummulites, which developed in a deeper and oligophotic environment and in a general context of humid climate conditions. The second sequence is formed by progradational deltaic deposits rich in Nummulites and developed under more arid climate conditions. Coralgal buildups occur interdigitated with these deltaic deposits forming two different lens-shaped bioherms that resulted in a coalescent buildup, with coral colonies sparse in a skeletal matrix of different grain-size. Corals grew in the mesophotic zone of the deltaic system affected by light fluctuations during periods of low siliciclastic input. The coralgal buildups of Sant Martí Xic Formation were thus influenced both by climatic changes and by the local detrital input from a deltaic system, associated with the uplift of the Catalan Coastal Range, highlighting the resilience of Eocene corals to environmental change. Geologica Acta, vol. 23, no. 16, 31 p. Oskay R.G. (2025).- Coal properties of Carboniferous Kurtköy coals (Zonguldak, NW Türkiye): Emphasis on rank, provenance of minerals and hydrocarbon generation potential- Late Carboniferous coal seams in the Zonguldak Basin (NW Türkiye) underwent several tectonic movements after the Late Permian; hence, these seams exhibit rank variations. This study presents initial insights into coal rank, mineralogical compositions, and hydrocarbon generation potential of Serpukhovian-Bashkirian coals within the Alacaagzi Formation from the south-easternmost part of the Basin. The examined seams are of bituminous C rank, and Tmax (442–445°C) and HI (221–288mg HC/g TOC) values indicate that they are at the set of oil generation. However, the low PI (0.01–0.02), BI (0.03–0.06), and QI (2.2–2.9) values and the possible presence of preserved cytoplasm spore-filling within the sporinite grains may indicate that the studied coals have only gas-generation potential. The results also show that the studied coals display relatively lower random vitrinite reflectance (%Rr 0.75–0.82%) and calculated Tpeak values (113–123ºC) using %Rr and micro-Raman spectra than their counterparts in the northern parts of the Basin (%Rr 1.18–1.52% and 173–206ºC). This difference seems to be related to the shallower burial depths of the studied coals or to the fact that they experienced relatively lower maximum attained temperatures than the northern parts of the Basin. Furthermore, the coal petrography and SEM-EDS data also suggest that the post-coalification tectonic deformation in the study area created space for circulating Ca- and Si-rich solutions within the coal seams and controlled epigenetic mineralization. Nevertheless, the redox conditions and clastic influx into the palaeomires also controlled syngenetic mineral formations, similar to the other parts of the Basin. Geologica Acta, vol. 23, no. 17, 22 p. Skelton P.W. & Gili E. (2025).- Myths and models of rudist ecology- Characterizing the ecology of rudist bivalves has long proved challenging, given their baroque shell shapes and the inconvenience of their extinction. Contrasting interpretations have taken hold in the literature via two different approaches. On the one hand, the appealing but simplistic hypothesis of ‘rudist reefs’ based on analogy with recent tropical coral reefs has been uncritically accepted by many, ignoring both the contrasts between the organisms concerned and the differing effects on sedimentation of icehouse versus greenhouse patterns of sea-level change. Worse, untested speculations have been spun on this suspect foundation, including the hypotheses of widespread photosymbiosis in rudists and of their competitive displacement of corals. On the other hand, opposed to such myth-making is an approach that respects the primacy of evidence. Here, synthetic interpretative models of rudist formations are built up from all circumstantial considerations and iteratively tested for compliance with field and laboratory observations. This process involves collating evidence ranging from well-supported inferences concerning rudist and coral palaeobiology, and growth fabrics and sedimentological contexts, to larger scale reconstructions of facies anatomy. The picture that commonly emerges –in contrast to the classic actualistic barrier-reef model– is of opportunistic settlements of usually low relief on flat-topped, tabular-bedded platforms distally grading into flanking clinoforms, without distinct intervening reefal edifices. Opportunities to test such synthetic models are provided by exceptional outcrops that display the full panorama of facies relationships. The latter is one of many achievements of detailed field studies over many years by the ‘Ramon Salas School’ in the Maestrat Basin. Geologica Acta, vol. 23, no. 18, 26 p. Ossò A., Artal P., Bakel B.W.M. van & Ferrer O. (2025).- Decapod fauna from the lower Aptian in the Valencian sector of the Maestrat Basin (NE Iberia)- The Forcall Formation in the Morella and Orpesa sub-basins of the Valencian sector of the Maestrat Basin has yielded a diverse assemblage of decapod crustaceans. A total of thirteen taxa are documented, representing the infraorders Achelata, Astacidea, Glypheidea, Axiidea, Anomura and Brachyura. Among these, one new genus, three new species, and one new taxonomic combination are proposed: Viapagurus covavidrensis n. sp., Eomunidopsis rigolleti n. sp., Morellosia maestratensis n. gen., n. sp., and Distefania pimientai n. comb. Comparisons with decapod faunas from other sub-basins of the Maestrat Basin reveal a notable degree of faunal homogeneity across the region. Furthermore, the palaeobiogeographic implications of these assemblages provide new insights into the distribution and diversity of Aptian decapod crustaceans. The findings highlight a significant faunal similarity with coeval basins such as the Garraf and Basque-Cantabrian basins and underscore the potential role of the Maestrat Basin as a biogeographic corridor linking decapod faunas of the Tethyan and Boreal realms. Overall, this study contributes to a more comprehensive understanding of the decapod assemblages of the Forcall Fm. and their relationships with contemporaneous faunas in the western Maestrat Basin and beyond. | |
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