Search results for "Logic"
showing 10 items of 33629 documents
Revision of the genus Anasibirites Mojsisovics (Ammonoidea): An iconic and cosmopolitan taxon of the late Smithian (Early Triassic) extinction
2016
34 pages; International audience; The family Prionitidae Hyatt represents a major component of ammonoid faunas during the Smithian (Early Triassic), and the genus Anasibirites Mojsisovics is the most emblematic taxon of this family. Its stratigraphical range is restricted to the beginning of the late Smithian (Wasatchites distractus Zone). The genus is also characterized by an unusual cosmopolitan distribution, thus contrasting with most earlier Smithian ammonoid distributions that were typically restricted by latitude. Because the late Smithian witnessed an extinction of the nekton (e.g. ammonoids, conodonts) whose amplitude is equal to or larger than that of the end-Permian crisis, the nu…
Trilobites from the Red Fauna (latest Emsian, Devonian) of Hamar Laghdad, Morocco and their biodiversity
2018
36 pages; International audience; Trilobites are widespread in Early Devonian deposits of north Gondwana; some of the most emblematic ones were collected from the famous latest Emsian (Early Devonian) mudmound locality Hamar Laghdad in south-eastern Morocco. This locality is famous for its trilobites, especially for the conspicuous red-coloured remains of phacopid trilobites with often greenish eyes. Here, we present a taxonomic revision of the previously described trilobites from the so-called Red Fauna of Hamar Laghdad. We introduce the new taxa Harpes hamarlaghdadensis n. sp. and Morocops davidbrutoni n. sp. Phacopids dominate the trilobite assemblage from the Red Cliff at Hamar Laghdad …
Raw material, gestures, artefacts. An approach to the work of bone and ivory in the Iron Age in the Iberian peninsula
2018
Abstract This work seeks to give visibility to the industry of hard animal materials that is documented during the Iron Age in the Iberian peninsula. We focus on the analysis of three common artefacts within the bone and ivory industry in the Iberian culture (between the 6th to the 1st Century BC): pins, perforated plates and combs. We have studied these objects from a technological point of view, thanks to a series of experimental work carried out in order to meet different operational chains, necessary to manufacture each one of these items and tools that could be used for this purpose. So, we searched the archaeological tool models to work bone and ivory, and whenever it has been possibl…
Annually resolved δ<sup>2</sup>H tree-ring chronology of the lignin methoxyl groups from Germany reflects averaged Wester…
2019
Abstract. Stable hydrogen isotopes ratios of lignin methoxyl groups (expressed as δ2HLM) of wood have been shown to reflect the climate-sensitive δ2H values of precipitation (expressed as δ2Hprecip) modulated by a large uniform negative isotope fractionation. However, a detailed calibration study among temporal variabilities of δ2HLM in tree-ring series, site-specific δ2Hprecip and climate parameters has not been performed yet. Here, we present annually resolved δ2HLM values from nine tree-ring series (derived from four Fagus sylvatica L. trees) collected near stations of the Global Isotope Network of Isotopes in Precipitation (GNIP) and the Deutsche Wetterdienst (DWD) meteorological observ…
A new species ofPlesiodimylus(Dimylidae, Eulipotyphla, Mammalia) from the Early Miocene of Spain
2017
AbstractWe report a new dimylid species, Plesiodimylus ilercavonicus sp. nov., from the Early Miocene locality of Mas d’Antolino B-5 (Ribesalbes-Alcora, Castello, Spain). This new species of Plesiodimylus is an amblyodont form of the genus and exhibits some primitive characters. The phylogenetic and palaeoenvironmental implications of this southern occurrence of Plesiodimylus in Lower Miocene sediments are discussed.urn:lsid:zoobank.org:act:EB5435A4-EECE-4B88-B5AC-4B77E2E13029
Carbon, nitrogen and oxygen isotope fractionation during food cooking: Implications for the interpretation of the fossil human record.
2017
13 pages; International audience; ObjectivesStable isotope data provide insight into the reconstruction of ancient human diet. However, cooking may alter the original stable isotope compositions of food due to losses and modifications of biochemical and water components.MethodsTo address this issue, carbon, nitrogen and oxygen isotope ratios were measured on meat aliquots sampled from various animals such as pork, beef, duck and chicken, and also from the flesh of fishes such as salmon, European seabass, European pilchard, sole, gilt-head bream, and tuna. For each specimen, three pieces were cooked according to the three most commonly-known cooking practices: boiling, frying and roasting on…
Introducing the Human Factor in Predictive Modelling: a Work in Progress
2012
International audience; In this paper we present the results of a study into integrating socio-cultural factors into predictive modelling. So far, predictive modelling has largely neglected the social and cultural dimensions of past landscapes. To maintain its value for archaeological research, therefore, it needs new methodologies, concepts and theories. For this study, we have departed from the methodology developed in the 1990s during the Archaeomedes Project. In this project, cross-regional comparisons of settlement location factors were made by analyzing the environmental context of Roman settlements in the French Rhône Valley. For the current research, we expanded the set of variables…
High-resolution clay mineralogy as a proxy for orbital tuning: example of the Hauterivian-Barremian transition in the Betic Cordillera (SE Spain).
2012
11 pages; International audience; The response of clay mineral assemblages to potential orbital forcing is tested in Mesozoic hemipelagic marl- limestone rhythmites of the Río Argos section (Betic Cordillera, Southeastern Spain). Along the section, marls are pervasively enriched in kaolinite and illite, whereas limestones are enriched in smectite-rich illite/smectite mixed-layers, suggesting that marl-limestone alternations are produced by cyclic high-frequency fluctuations of continental runoff. Spectral analyses show that clay mineral assemblages evolve accordingly to precession, obliquity and eccentricity cycles. Durations of ammonite zones are assessed at 535 kyr for the Late Hauterivia…
The end of the Messinian salinity crisis: Evidences from the Chelif Basin (Algeria).
2007
How did the Messinian Salinity Crisis end is a matter of intense debate between two opposite concepts i.e., the generalised dilution event, the so-called Lago–Mare, followed by the sudden restoration of the marine conditions at the base of the Zanclean, or the early partial or complete marine refill that would have happened earlier during the upper Messinian. The Chelif Basin of Northwestern Algeria, one of the greatest Messinian marginal basins of the Mediterranean, provides an exceptional opportunity to study in detail how this major paleoenvironmental change occurred through continuous sedimentary records of the Miocene–Pliocene boundary. Five sections representative of both the central …
Bats from the classical site of Venta del Moro (Late Miocene, Eastern Spain)
2017
The presence of bat fossils in localities of fluvio-lacustrine origin is quite uncommon, and usually these remains are poorly preserved or not studied in detail. In the present work we study the ba...