Search results for "Miocene"
showing 10 items of 116 documents
Efficient recycling of nutrients in modern and past hypersaline environments
2019
The biogeochemistry of hypersaline environments is strongly influenced by changes in biological processes and physicochemical parameters. Although massive evaporation events have occurred repeatedly throughout Earth history, their biogeochemical cycles and global impact remain poorly understood. Here, we provide the first nitrogen isotopic data for nutrients and chloropigments from modern shallow hypersaline environments (solar salterns, Trapani, Italy) and apply the obtained insights to ¿ 15 N signatures of the Messinian salinity crisis (MSC) in the late Miocene. Concentrations and ¿ 15 N of chlorophyll a, bacteriochlorophyll a, nitrate, and ammonium in benthic microbial mats indicate that…
Microwear textures associated with experimental near-natural diets suggest that seeds and hard insect body parts cause high enamel surface complexity…
2022
In mammals, complex dental microwear textures (DMT) representing differently sized and shaped enamel lesions overlaying each other have traditionally been associated with the seeds and kernels in frugivorous diets, as well as with sclerotized insect cuticles. Recently, this notion has been challenged by field observations as well as in vitro experimental data. It remains unclear to what extent each food item contributes to the complexity level and is reflected by the surface texture of the respective tooth position along the molar tooth row. To clarify the potential of seeds and other abrasive dietary items to cause complex microwear textures, we conducted a controlled feeding experiment wi…
Allopolyploidisation in a geological collision zone: on the origin of the tetraploid Anthemis cupaniana Nyman (Compositae, Anthemideae) in Sicily
2022
AbstractThe genus Anthemis has a circum-Mediterranean distribution and comprises c. 175 annual, biennial, and perennial species with polyploid species and species complexes found in its section A. sect. Hiorthia. In Sicily, the genus is represented by 13 species, one of these being the tetraploid A. cupaniana, which is endemic to the island and is distributed throughout the limestone mountains at elevations between 500 and 1800 m a.s.l. Discordant positions in phylogenetic trees based on two plastid regions (psbA-trnH and trnC-petN) and on one nuclear marker (nrDNA ITS1 + 5.8S + ITS2) reveal that the species is of allopolyploid origin, with the maternal parent from the species group around …
Thermomineral waters of Greece: geochemical characterization
2020
Estratigrafía y petrología del subsuelo precuaternario del sector SW de la depresión de Barcelona (Cadenas Costeras Catalanas, NE de Iberia)
2008
Juan.Usera@uv.es Las numerosas obras de Ingeniería Civil que se han realizado en los últimos años en la depresión de Barcelona (ampliación del aeropuerto, ampliación del metro y AVE fundamentalmente) han permitido recabar mucha información sobre el subsuelo de esta área. En este trabajo se caracterizan las distintas unidades de subsuelo precuaternarias que aparecen en los numerosos sondeos realizados recientemente en la zona SW de la depresión de Barcelona. Se ha identificado un sustrato triásico formado por areniscas del Buntsandstein y dos unidades de edad Miocena, una basal de carácter continental y otra superior depositada en un ambiente marino. Todas estas unidades fueron fracturadas d…
Un nuevo suido con dientes yugales tubulidentados e hipselorrizos del Mioceno inferior de Córcoles, España
2018
[EN] Excavations at Córcoles, Guadalajara, Spain (MN 4) in October 1987, yielded a mandible and several isolated teeth of a strange suiform with tubulidentate cheek teeth, initially interpreted to be the remains of Tubulidentata. The specimens are complete enough to remove any doubt about which Order (Artiodactyla) and Superfamily (Suoidea) they belong to. They are here attributed to the Family Doliochoeridae, being related to the genera Bransatochoerus (MP 30) and Lorancahyus (MN 2) both of which have hypsorhizic cheek teeth, the latter with tubules in the teeth, but not to the fully-expressed extent seen in the fossils from Córcoles and the molars retain a distinct and large pulp cavity, …
Tiburones de aguas profundas en el Mioceno medio de Alicante: implicaciones para la recuperación de los ecosistemas abisales mediterráneos después de…
2017
El estudio de la localidad clásica de El Chorrillo del Mioceno Medio (Serravaliense) en la Provincia de Alicante, ha permitido la recuperación de una interesante asociación de microrestos de tiburones caracterizada por al menos siete taxones (Deania calcea, ¿Isistius triangulus, ¿Squaliolus cf. schaubi, ¿Paraetmopterus sp., Pristiophorus sp., Scyliorhinus sp. y un Squaliforme indeterminado) pertenecientes a tres órdenes diferentes (Squaliformes, Pristiophoriformes y Carcharhiniformes). Asociados a estos microrestos se han identificado también macrodientes pertenecientes a Cosmopolitodus hastalis, Isurus sp., Hemipristis serra, Odontaspis sp., Carcharhinus spp. y ¿Otodus (Megaselachus) megal…
Major palaeohydrographic changes in Alpine foreland during the Pliocene - Pleistocene
2008
International audience; The changing palaeogeographical pattern of Alpine deposits across the European forelands can be traced by identifying mineral assemblages and establishing the chronology of Pliocene-Pleistocene deposits in Alpine foreland. In the late Miocene, the upper courses of the Rhine and the Aar flowed east from the Swiss molasse plain towards the Danube. In the early Pliocene (Brunssumian, 5-3.2 Ma), these same rivers headed north-wards towards the Rhine Graben of Alsace. In the early Reuverian, these streams were captured south of the Rhine Graben by the Doubs. They ceased their northward flow and headed west to feed the Bresse Graben. This phase is dated to the Lower and Mi…
Las costas rocosas del Migjorn de Menorca: acantilados y calas
2017
[spa]La zona meridional de Menorca (Migjorn) se caracteriza por ser una plataforma carbonatada desarrollada en un ambiente arrecifal durante el Mioceno superior. Está surcada por una serie de cursos torrenciales fuertemente encajados que en su desembocadura al mar dan lugar a una forma de bahía denominada “cala” que está delimitada por paredes de elevada pendiente. La fracturación y la diaclasación penetrativa que afecta a la alternancia de materiales calcareníticos y calcisiltiticos miocenos, junto con la distribución de éstos, es el principal factor que condiciona el trazado de los cursos fluviales, así como el desarrollo de los procesos de tipo kárstico asociados a la circulaci…
Structural highs formation and their relationship to sedimentary basins in the north Sicily continental margin (southern Tyrrhenian Sea): implication…
2005
Two high-penetration seismic profiles across the continental margin of north Sicily (southern Tyrrhenian Sea) have been interpreted to construct a crustal section across the margin and to provide a three-dimensional perspective on the upper crustal setting of the Solunto High and its structural relationships with the adjacent Cefalù Basin. Crystalline rocks of the Kabilian-Calabrian Units (KCU) are recognized in the Solunto High region and farther to the north. The KCU body is tectonically superimposed onto sedimentary rocks pertaining to the Sicilian-Maghrebian Units (SMU) and the Solunto High corresponds to the thrust sheet culmination. Its occurrence in the Solunto High demonstrates that…