Search results for " pliocene"
showing 10 items of 17 documents
Growth-increment characteristics and isotopic (delta O-18) temperature record of sub- thermocline Aequipecten opercularis (Mollusca: Bivalvia): evide…
2021
Abstract The shell δ18O of young modern Aequipecten opercularis from the southern North Sea provides an essentially faithful record of seasonal variation in seafloor temperature. In this well-mixed setting, A. opercularis shell δ18O also serves as a proxy for seasonal variation in surface temperature. Individuals from less agitated (e.g. deeper) settings in a warm climate would not be expected to record the full seasonal range in surface temperature because of thermal stratification in summer. Such circumstances have been invoked to explain cool isotopic summer temperatures from early Pliocene A. opercularis of eastern England. Support for a sub-thermocline setting derives from high-amplitu…
Petrography and carbonate isotope stratigraphy from MIS AND-1B core, Antarctica: Evidence of the early Pliocene warming event
2011
Abstract A large portion of ANDRILL (ANtarctic geological DRILLing) core AND-1B recovered in the Western Ross Sea and spanning the early Pliocene has been investigated in order to obtain a detailed carbonate isotope record from Antarctic margin sediments through the early Pliocene warming event. Petrographic observations and mineralogical analyses reveal the authigenic nature of the carbonate and small proportions of Fe and Mg incorporated within the calcite lattice. High productivity conditions testified by ~ 80 m-thick diatomite interval (383 to 460 mbsf) well fit with the composite nature of the authigenic carbonate generally characterizing organic matter-rich sediments. As is known, sed…
Witnesses of the early Pliocene sea-level rise in the Manilva Basin (Málaga, S Spain)
2020
The Sierra de la Utrera, a relief in the Manilva Basin (Malaga, SW Spain), shows bored surfaces at different heights above present-day sea level, from 96 m to 287 m. Borings occur in the eastern, central, and western parts of the Canuto de la Utrera, a prominent gorge in the central southern part of the relief excavated in Mesozoic limestones, as well as on the western end of the Canuto Chico, a smaller canyon in the northern part. Pliocene marine deposits fossilized the bored surfaces. Bored boulders of the substrate are embedded in the Pliocene sediments. The traces Gastrochaenolites ispp., Entobia ispp., Caulostrepsis ispp., Circolites kotoucensis, and Ericichnus asgaardi have been ident…
Stratigraphic frame work of the type locality of Pirro Nord Mammal Faunal Unit (Late Villafranchian, Apricena south-eastern Italy)
2013
The fossiliferous karst deposits of the typical Pirro Nord Faunal Unit recently revived interest for the lithic tools documenting the human occurrence in southern Italy at Early Pleistocene. Therefore, a revision of the Pliocene to lowermost Pleistocene stratigraphic succession was needed. It was carried on with a twofold aim: to detail the stratigraphic architecture and the structural-depositional evolution of the “Apricena horst”, and to verify the chronostratigraphic constraints for the Pirro Nord F.U. in the type area of Apricena. The stratigraphic record has been subdivided in four units bounded by ubiquitous unconformity surfaces, often associated to evidence of sub-aerial exposure. F…
THE GARGANO TERRE ROSSE INSULAR FAUNAS: AN OVERVIEW
2010
After forty years from its discovery, the history of the field surveys and of the researches on the fossiliferous deposits on Gargano is briefly reported. The Gargano fauna belongs to the Abruzzo-Apulian Palaeobioprovince (including also Scontrone and Palena, Abruzzo). The fossil assemblage comprehends all the classes of terrestrial vertebrates: Reptilia, Amphibia, Aves and Mammalia. The faunal composition is unbalanced and presents the features of a typical insular endemic fauna. The bulk of the assemblage is composed of small mammals and birds. Based on literature, we report the most characteristic features, phylogenetic relationships, and evolutionary remarks on a list of mammals, focusi…
Pliocene sapropels in the northern Adriatic area: chronology and paleoenvironmental significance
1997
Abstract A detailed stratigraphic and paleoenvironmental study was carried out ona marine section from the Marecchia Valley in the Northern Apennines. The section consists predominantly of deep-water hemipelagic clays intercalated with 15 thick, laminated sapropels (M1–M15). Based on biostratigraphic (calcareous nannoplankton and planktonic foraminifera) and magnetostratigraphic results, the Marecchia Valley section is interpreted as being middle to late Pliocene in age, extending from the upper part of the Gauss Chron to the lower part of the Matuyama Chron. The high resolution stratigraphy allows us to correlate, for the first time, these northern Italian sapropels with sapropels previous…
Reconstruction of the paleoenvironmental changes around the Messinian-Pliocene boundary along a W-E transect across the Mediterranean
2004
Tectono-sedimentary evolution of the Pliocene to Lower Pleistocene succession of the Apricena-Lesina-Poggio Imperiale quarrying district (western Gar…
2010
The post-Miocene marine succession of the «Apricena horst» is described with the purpose to verify the chronostratigraphic constraints for the type-locality of the Pirro Nord Faunal Unit. The stratigraphic succession has been subdivided in four units bounded by ubiquitous unconformities with evidence of subaerial exposure. The two basal units (dated late Zanclean to at most early Piacenzian) are formally grouped in the Lago di Varano Fm. that on the whole consists of sediments ranging from lagoonal to circalittoral environments. Within the lowermost unit, a megabreccia is interpreted as the product of a tsunami event. The third unit, Gelasian in age, is informally cited as Calcari a Briozoi…
Late Pliocene and Pleistocene small mammal chronology in the Italian peninsula
2007
The abundant documentation of small mammals in the Italian peninsula, collected over recent years, furnishes a detailed biochronological sequence mainly from the Late Pliocene onwards. An updated stratigraphic framework is here presented, based on the European small mammal biozonation. The Early Villanyian is characterized by Mimomys hassiacus, M. stehlini, and, later, poorly documented M. polonicus. The Late Villanyian localities are well characterized with M. pliocaenicus, M. pitymyoides and M. tigliensis. The older part of the Early Biharian is documented by assemblages containing Microtus (Allophaiomys) ex gr. pliocaenicus, M. pusillus, M. cf. ostramosensis and M. tornensis, while the l…