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MorphoMuseuM, vol. 11, 3 p. Tabuce R. & Gernelle K. (2025).- 3D models related to the publication: European mammal turnover driven by a global rapid warming event preceding the Paleocene-Eocene Thermal Maximum.- This contribution contains the 3D models described and figured in the following publication: Tabuce R., Marandat B., Adnet S., Gernelle K., Girard F., Marivaux L., Solé F., Schnyder J., Steurbaut E., Storme J.-Y., Vianey-Liaud M., Yans J. (2025). European mammal turnover driven by a global rapid warming event preceding the Paleocene-Eocene Thermal Maximum. Geologia Acta, vol. 23, no. 12, 24 + I p. Nurlu N. (2025).- New evidence on the timing of southern Neotethys closure from geochronology and geochemistry of Harmanli region ophiolite (southeastern Anatolia) and Late Cretaceous granitic rocks.- The felsic-intermediate intrusions of the Harmanli region are situated in proximity to the Tauride thrust front in southeastern Turkey. The region containing intrusive and ophiolitic rocks plays a crucial role in understanding the magmatic framework of Late Cretaceous felsic-intermediate igneous rocks in the Adiyaman region of southeastern Anatolia. The geological evolution of southeastern Anatolia during the Late Cretaceous is unravelled through integrated field observations, whole-rock geochemical, petrographic analyses, U-Pb zircon geochronology, and mineral chemistry of granitic rocks that intrude the Harmanli region ophiolite. The intrusions consist of tonalite, granodiorite, and in places granite, with a subvolcanic phase represented by granophyre, aplite, and granite porphyry. Mafic rocks including gabbro and diorite are also present with microdiorite and diabase in the subvolcanic phase. The new, high-precision LA-ICP-MS U-Pb zircon data provides crystallization ages for the mafic rocks of the Harmanli ophiolite (gabbro) ranging from 83.8 to 81.7Ma, while the felsic intrusives (granodiorite) have yielded crystallization ages ranging from 80.8 to 79.5Ma. Geochemical data indicate calc-alkaline, I-type magmatism characteristic of a subduction zone environment, consistent with the northward-dipping subduction of the southern Neotethys beneath the Tauride platform. The magmatic arc environment is characterised by the presence of ocean-ridge granite-normalised multi-element patterns, tectonomagmatic discrimination, and the biotite geochemistry of the intruded rocks. The mafic rocks of Harmanli region ophiolite exhibit distinct characteristics, including i) depletion in Nb, ii) enrichment in LILEs (Ce, Rb, K, and Th) and iii) a nearly horizontal pattern of HFSEs (high field strength elements) compared to N-MORB. The results suggest that the magmatism occurred during the Late Cretaceous (Campanian), with the intrusions forming at moderate to shallow crustal depths. Acta Palaeontologica Romaniae, vol. 21, no. 02, p. 3-10 Felix Schlagintweit, Koorosh Rashidi & Reza Hanifzadeh.- Data on the unknown: The embryo of Iraqia simplex Henson, 1948 (larger benthic foraminifera; early Aptian, central iran).- Iraqia simplex Henson, the type-species of this orbitolinid genus, is classified among the Dictyoconinae Schubert that is principally defined by a simple megalospheric embryo. However, neither the original nor any later description of the taxon contained any specifications (or illustration) of this taxonomically important feature except that it should be situated eccentrically at the beginning of an early spiral stage. Abundant material from the early Aptian Taft Formation of Central Iran, that is in perfect conformity with Henson's Iraqi type-material, shows the presence of a simple embryo positioned centrically at the apex of the generally high-conical tests. Apart from other differences in the internal test structure, this feature therefore appears to represent a further distinguishing criterion to the allied genus Orbitolinopsis Henson. The available material also provides a relatively good overview of the so far unknown embryo's biometric variability. Among the Dictyoconinae, a centric embryo can be considered as the
exception rather than the rule. PalæoVertebrata, vol. 48, no. 1, 11 p. Lemierre A. & Orliac M.J.- Lissamphibians from Dams (Quercy, SW France): Taxonomic identification and evolution across the Eocene-Oligocene transition.- The locality of Dams (Quercy, southwestern France) has yielded two fossil assemblages, one from the late Eocene and another from the early Oligocene, making it one of the few localities with infillings across the Eocene-Oligocene transition. At least 24 taxa (13 mammals, 11 snakes) have been identified in this locality. Study of the lissamphibian remains from Dams yields an Eocene and an Oligocene assemblage, with a total of eight taxa. The Eocene assemblage includes two unnamed salamandrine species, one unnamed pelobatid species and one pyxicephalid species (Thaumastosaurus). The Oligocene assemblage includes two unnamed pleurodeline species, one salamandrine species (Salamandra sansaniensis) and an unnamed pelobatid species. Among the eight taxa from Dams, one Eocene salamandrine and one Oligocene pleurodeline are identified for the first time in the Quercy. A review of the lissamphibians from the Quercy area identifies eleven taxa for the Late Eocene (MP19) and eight taxa for Early Oligocene (MP22), with a major turnover at the Eocene-Oligocene transition. This turnover occurs in a time of major climatic changes, with a significant decrease in temperature and precipitation and concurrent increase in seasonality in Europe, likely affecting specialized taxa. Carnets Geol., vol. 25, no. 09 Stéphane Bersac & Didier Bert.- The Deshayesitidae (Ammonoidea, Ancyloceratina) in the lower Aptian (Lower Cretaceous) of the Les Ferres Aptian Basin (southeastern France).- In the present work, we study 335 specimens of Deshayesitidae (Ammonoidea) from the vicinity of the village of Les Ferres (SE France). The Deshayesitidae is the current key family for the ammonite biostratigraphy of the lower Aptian (Lower Cretaceous). Despite poorly preserved, the studied material could have been identified at species rank in most cases and allowed establishing the biostratigraphic frame of the lower Aptian of the study area. The results are as follows: (1) the studied samples range from the Deshayesites forbesi Zone to the Dufrenoyia furcata Zone; (2) their ontogenetic sequence is described; (3) their evolutionary patterns are consistent with those observed in other samples of Deshayesitidae; (4) no dimorphism is conspicuous; (5) the identified taxa are, from earliest to latest: Deshayesites sp. (Deshayesites forbesi Zone, rounded ventral area probably without smooth siphonal band), Deshayesites multicostatus Swinnerton, 1935 (index of subzone, intermediate smooth siphonal band then rounded ventral area), Deshayesites grandis Spath, 1930 (index of subzone, longer smooth siphonal band then subtabulate ventral area on phragmocone), Dufrenoyia furcata (J. de C. Sowerby, 1836) (index of subzone and zone, even longer smooth siphonal band then subtabulate ventral area, onset of rounded to claviform latero-ventral tubercles in inner whorls) and Dufrenoyia dufrenoyi (Orbigny, 1841) (index of subzone, even more longer smooth siphonal band, latero-ventral tubercles claviform only). The Sedimentary Record, vol. 23, no. 1, p. 43-64 Rivera T., Malone D.H., Biek R.F., Lesmann S.R., Stevens G., Hacker D., Braunagel M.J., Griffith W.A. & Rowley P.D. (2025).- The Growth and Collapse of a Volcanic Field: Detrital Zircon U/Pb Geochronology and Provenance of the Oligocene Bear Valley Formation, Southwest Utah, USA.-The Bear Valley Formation (Fm.) is a distinctive eolian sandstone interbedded with thick volcanic rocks of the Marysvale volcanic field of southwest Utah, the southern part of which failed during eruptive activity along three mega-scale gravity slides. The formation is as thick as 300 m and extends over an area of >2,500 km2 in the Black Mountains and Markagunt Plateau. The Bear Valley Fm. is composed of tuffaceous sandstone interbedded with tuff, conglomerate, and polymict volcanic mudflow breccias. The sandstone beds are lithic arenite and lithic wacke that occur as massive beds with large-scale cross bedding. The Bear Valley Fm. occurs in the upper plate of the Markagunt gravity slide and is in both the upper and lower plates of the Black Mountains gravity slide. We used laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to acquire U/Pb dates of detrital zircons (N = 3, n = 346) from the autochthonous Bear Valley Fm. at Kane Spring and Jako Wash in the Black Mountains and the allochthonous Bear Valley at Sandy Wash in the central Markagunt Plateau. All samples are dominated by Oligocene zircons with maximum likelihood ages for deposition ranging from 23.6 to 24.0 Ma. The western-most sample from Jako Wash also preserves a slightly older group of zircons, indicating derivation from either the underlying Wah Wah Springs Fm. or another unit erupted from the Indian Peak caldera complex to the west. Thus, the upper Bear Valley Fm. was deposited within ~400 kyr before the emplacement of the Markagunt gravity slide at 23 Ma, reflecting accelerated uplift of the northern Marysvale complex that ultimately resulted in collapse and slide emplacement. Geologia Acta, vol. 23, no. 11, 19 p. Martín-Closas C., Albalat D., Colombo F., Vilà M., Vicente A., Ossó À., Vicedo V. & Bover-Arnal T. (2025).- A refugium for charophytes during the maximum post-Palaeozoic sea-level highstand in the Turonian of Tarragona (Catalonia, Spain).- During the Cenomanian-Turonian interval, Europe was largely submerged under a shallow tropical sea within the Cretaceous Tethyan Archipelago, limiting non-marine lacustrine habitats to a few coastal lakes on the islands. This study reports an island refugium for charophytes in the Upper Cretaceous of Tarragona located at the palaeo-shores of the former Ebro Massif. The Upper Cretaceous of Tarragona comprises three carbonate formations that record a Cenomanian-Turonian transgressive-regressive sequence. This sequence is represented by a shallow marine platform to pelagic facies at the base, overlain by lacustrine and palustrine facies at the top. These non-marine deposits are newly attributed to the Turonian, based on the stratigraphic context and the presence of the species Atopochara trivolvis var. multivolvis. In addition to this dominant species, the charophyte assemblage contains a clavatoroidean species, represented by the thallus Munieria grambastii forma sarda, and is associated with freshwater gastropods. A. trivolvisvar. multivolvis had a wide distribution in the Northern Hemisphere at a palaeolatitude of around 40°N, occurring in the United States, Spain, France, and Armenia. The European localities suggest that the island charophyte flora in the Cretaceous Tethyan Archipelago was an impoverished version of the pre-highstand Early Cretaceous flora, which was dominated by clavatoraceans. This contrasts with coeval floras from the mainland (Chinese and Argentinian basins), where Turonian charophyte communities were diverse and already dominated by modern characean genera. The island lakes acted as refugia for the last clavatoracean-dominated charophyte communities before their complete replacement by modern characean communities during the latest Cretaceous. Carnets Geol., vol. 25, no. 08 Olev Vinn, Magdy El Hedeny, Mansour I. Almansour, Saleh Alfarraj & Ursula Toom.- The first record of a possible 'priapulid' from the lower Cambrian (Series 2) of Estonia.- The Yunnanpriapulus? sp. can be divided into three distinct parts: an anterior introvert, a slightly constricted elongated neck, and a slightly bulbous elongated posterior trunk. The fossil is preserved as a three-dimensional cast in the fine-grained sandstone and is oriented parallel to the bedding plane. Rapid burial helped protect the organism from scavengers and decay and provided the opportunity for fossilization via pyritization. The preservation of the specimen on a bedding plane resulted from the post-mortem transportation of the dead animal, likely due to a storm event. The priapulid likely hunted other worms for food. The similarity of the Estonian specimen to the Chinese species suggests that there may have been some faunal exchange between the remote continents of Baltica and South China in the early Cambrian. Geologia Acta, vol. 23, no. 10, 32 + III p. Larena Z., Arenas C., Ortiz J.E., Sanjuan J., Pascual A., Larraz M., Murelaga X. & Baceta J.I. (2025).- Quaternary tufas of the Inglares River valley: An example of changing slope stepped fluvial system, Álava, N Spain.- This study examines the factors that controlled the formation of Quaternary calcareous tufa deposits along the valley of the Inglares River (Álava, north Spain), currently fed by a karst-carbonate aquifer. It is based on stratigraphic, chronological (Amino Acid Racemisation, AAR), sedimentological, and δ13C and δ18O analyses, complemented by palaeontology (molluscs, ostracods and charophytes). The examined deposits occur as isolated bodies in the uppermost and downmost stretches of the valley, reaching45 and 25m in thickness, respectively. AAR dating classified them into two groups: Middle-Late Pleistocene (MIS 5e) and Middle and Late Holocene (MIS 1). The former only occurred in the downstream stretch. Up to eleven carbonate facies and minor allochthonous coarse detrital facies have been characterised and arranged into four distinct facies associations. Their features and bedding geometries suggested two main depositional settings: a low- to moderate-slope stepped stretch with small barrage cascades, dammed areas, and abundant palustrine zones (downstream system) and a high-slope stretch with steep stepped cascades and pools (upstream system). These settings respond to bedrock lithology and structural changes throughout the valley, which appear to be the principal factors controlling the tufa depositional architecture. Based on δ13C, an increase in aridity was inferred from the Middle-Late Pleistocene to Holocene. The isotopic differences between the upstream and downstream Holocene tufa might reflect the spatial evolution of δ13Cand δ18O in stream water through the approximately 8km long surveyed transect. Erosion due to sudden changes in water discharge may have caused the stratigraphic gap between the two tufa groups. Geologica Belgica, vol. 28, no. 1-2, p. 47-71 Coen-Aubert M.- Description of some Middle Devonian rugose corals from the Ma'der (eastern Anti-Atlas, Morocco).- Twelve species and four forms of Middle Devonian rugose corals from Morocco are described and illustrated. The material comes from four localities of the Ma'der Basin whose age from the Late Eifelian to the base of the middle Givetian is based on conodonts. Three taxa are new: Marennophyllum kaufmanni n. sp., Stringophyllum pedderi n. sp. and Siphonophrentis subaequalis n. sp. Heliophyllum moghrabiense Le Maître, 1947 is the only taxon common to the four outcrops and it suggests an Eastern North American influence at the level of the genus. Siphonophrentis cantabrica Birenheide, 1978, first described from Spain, is also a North Gondwanan species whereas Stringophyllum acanthicum (Frech, 1885), Acanthophyllum heterophyllum (Milne-Edwards & Haime, 1851), A. vermiculare (Goldfuss, 1826) and Spinophyllum blacourti (Rohart, 1988) are interesting for correlations with Western Europe and sometimes with Eastern Europe. Enallophrentis corniformis (Gürich, 1896) was defined in Poland, also in the Old World Realm. Farther to the east, there is a link with China where Siphonophrentis cantabrica is present. Finally, it must be mentioned that Australophyllum Stumm, 1949 is observed for the first time in Morocco. | |
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