Search results for "FAC"
showing 10 items of 36366 documents
The response of a shallow lake and its catchment to Late Glacial climate changes — A case study from eastern Poland
2015
In this study we investigate how climate fluctuation in the Late Glacial period influenced the development of a lake and its catchment located in the East European Plain. We analyzed the sediments of the lake for pollen, subfossil Cladocera, macrofossils and chemical composition. We aimed at disentangling: (1) the climate changes and their limno-ecological responses, (2) temperature dynamics with the use of Cladocera-based transfer function (MJT) and macrofossil-based reconstruction of mean minimum July temperature (MMJT), (3) timing of the response of different proxies to environmental changes. The results of multiproxy analyses explicitly suggest that the main driver for changes in aquati…
North Atlantic Oscillation recorded in carbonate δ18O signature from Lagunillo del Tejo (Spain)
2016
Abstract Oxygen (δ18O) and carbon (δ13C) isotope compositions of authigenic carbonates measured in Lagunillo del Tejo sediment document precipitation variability during the last millennium in the Iberian Range. Modern water samples show that Lagunillo δ18O and δD plot below the Global Meteoric Water Line (GMWL). Sediment samples show a covariant trend between carbonate δ18O and δ13C, indicating that the precipitation/evaporation ratio has largely controlled the isotopic composition of this lake. This covariant trend is used to extract information about past lake level changes. Humid periods occurred around AD 1300–1450, AD 1620–1775 and AD 1950–1980, while the driest periods were concentrat…
Shell sclerochronology and stable isotopes of the bivalve Anomalocardia flexuosa (Linnaeus, 1767) from southern Brazil: Implications for environmenta…
2017
Abstract This study presents the first stable isotopic and sclerochronological calibration of the bivalve Anomalocardia flexuosa (Linnaeus, 1767) in relation to environmental variables in a subtropical coastal area of southern Brazil. We investigate incremental shell growth patterns and δ18O and δ13C values of modern specimens collected alive from the Laguna Lagoonal System (LLS). Shells of Anomalocardia flexuosa are also one of the main biological components of pre-Columbian archaeological shell mounds and middens distributed along the Brazilian coastline. We therefore selected archaeological specimens from a local late Holocene shell mound (Cabecuda) to compare their stable carbon and oxy…
Debitage by fracturing in the osseous industry of Cova del Parpalló (Gandía-Valencia, Spain): A preliminary study
2016
Abstract The excavations carried out by L. Pericot from 1929 to 1931 in the Cova del Parpallo documented the Gravettian in the base, a Solutrean layer, and a Magdalenian. This sequences comprise an exceptional assemblage of portable art because of the number of plaquets/objects and the great chronological amplitude. With all this information, Parpallo was included in the reduced list of reference sites to organize the European Upper Paleolithic sequence in the first half of the 20th century. The Magdalenian layers were organized in four phases, following H. Breuil's classical proposal. Changes in bases morphology and decorative topics on osseous points permitted this correlation, identifyin…
The Solutrean - Magdalenian Transition: a view from Iberia
2012
The paper examines the Upper SolutreaneArchaic Magdalenian/Badegoulian succession on the base of lithic and bone tool production, chrono-stratigraphic data and radiocarbon dates from the Cantabrian and Mediterranean regions of Iberia, mainly the areas of Asturias and Valencia (Spain). The discussion considers a reduced number of variables (characteristic stone tools, bone points and decoration techniques) and highlights the elements in common. The analysis concerning the transformation of lithic production at Cova del Parpallo provides new data for the Upper SolutreaneArchaic Magdalenian/ Badegoulian transition.
Experimental basis in lithic arrows usage and hafting at the end of the last glaciation in the French Alps
2017
Abstract To identify lithic arrowheads from Prehistoric sites is very difficult because there is a great variability in their morphology and in the ways of hafting and throwing them. Variables playing in their use are numerous. Some experimental approaches try to explain traces in prehistorical lithic points by mean of paying attention at some of these variables. Many researchers have used morphological parameters to distinguish spear from arrowheads, showing which characteristics define the potential of each type of weapon in ethnographical examples. However, only an accurate use-wear analysis that pays attention on macro and micro-wear traces and which is grounded on systematically experi…
Firewood and hearths: Middle Palaeolithic woody taxa distribution from El Salt, stratigraphic unit Xb (Eastern Iberia)
2017
Abstract Spatial analyses of Palaeolithic sites typically defined by hearth-related assemblages have been mostly based on lithic and faunal remains. By using spatial analysis methods in conjunction with analytical units with higher temporal resolution than typical stratigraphic units, synchronic and diachronic relationships between artifacts deposited during successive occupation events have been elucidated. Spatial analyses applied to archaeobotanical remains are scarce, and when available, are typically focused on carpological remains (seeds and fruits). The lack of spatial indicators among anthracological remains hampers obtaining significant data linked to the relationships established …
Mineral soil composition interfacing archaeology and chemistry
2016
Abstract In the last decade, different soil types have been analysed to evaluate the effect of human activities from an archaeological point of view. In particular, in the last few years, tremendous advances have been made in sample preparation and analytical methods used in archaeological soil analyses. However, there is still a need to set standardized protocols to achieve different archaeological goals. Therefore, in this study, the analytical methods available to study archaeological soils have been reviewed together with a critical discussion on the challenging archaeological questions, which could be answered by determining their mineral composition. Data on trace elements and rare ea…
Bird consumption in the final stage of Cova Negra (Xátiva, Valencia)
2016
This paper publishes the results of the study of bird remains from Cova Negra level IIIb, a level with Middle Palaeolithic industry that corresponds to the upper part of the sequence, where 247 bird remains from 18 species have been found. Doves and corvidae, particularly choughs (Pyrrhocorax sp.), are the species most frequently found. A substantial part of the remains analyzed displays human manipulation and consumption evidence, a clear indication of bird hunting and consumption by Neardental populations. The manipulation process and consumption of birds, in the context of Neanderthals' predatory activity during the final period of occupation of the site, is described in this paper. Furt…
Dental wear at macro- and microscopic scale in rabbits fed diets of different abrasiveness: A pilot investigation
2020
To differentiate the effects of internal and external abrasives on tooth wear, we performed a controlled feeding experiment in rabbits fed diets of varying phytolith content as an internal abrasive and with addition of sand as an external abrasive. 13 rabbits were each fed one of the following four pelleted diets with different abrasive characteristics (no phytoliths: lucerne L; phytoliths: grass G; more phytoliths: grass and rice hulls GR; phytoliths plus external abrasives: grass, rice hulls and sand GRS) for two weeks. At the end the feeding period, three tooth wear proxies were applied to quantify wear on the cheek teeth at macroscopic and microscopic wear scales: CT scans were obtained…