Search results for "Prove"

Uneven Data Quality and the Earliest Occupation of Europe—the Case of Untermassfeld (Germany)

2017

AbstractThe database regarding the earliest occupation of Europe has increased significantly in quantity and quality of data points over the last two decades, mainly through the addition of new sites as a result of long-term systematic excavations and large-scale prospections of Early and early Middle Pleistocene exposures. The site distribution pattern suggests an ephemeral presence of hominins in the south of Europe from around one million years ago, with occasional short northward expansions along the western coastal areas when temperate conditions permitted. From around 600,000-700,000 years ago Acheulean artefacts appear in Europe and somewhat later hominin presence seems to pick up, w…

Regional provenance of dolerite prehistoric objects through mineral analysis

2016

Abstract A methodology based on the mineral analysis determination has been developed to identify the origin of dolerite stone outcrops collected to fabricate lithic objects during the Prehistoric period. The method is based on the use of inductively coupled plasma mass spectrometry (ICP-MS) to analyse rare earth elements (REE) and trace elements. Additionally a no destructive geochemical analysis based on X-ray fluorescence (XRF) was employed for major elements analysis. The aforementioned methodologies were applied to samples from different archaeological fields or natural outcrops located in the Mediterranean area of Spain, between Valencia and Alicante. Principal component analysis (PCA…

Tectonic evolution of the northern Austral-Magallanes basin in the Southern Patagonian Andes from provenance analysis

2019

We studied the northern tip of the Austral-Magallanes basin in the Southern Patagonian Andes, between the Buenos Aires Lake and the Mayer River at 46°35′ SL and 48°35′ SL, respectively. Proposed objectives were: i) to differentiate Mesozoic-Cenozoic tectonostratigraphic units and, ii) to characterize the different deformational events that took place in the area linked to a variable regional geodynamic context. Sandstones provenance analysis was performed on the Aptian - Albian compressive retroarc deposits and Cenozoic foreland deposits. Studied samples were classified using tectonic discrimination diagrams which show: i) for Cretaceous rocks a dominant sediment source from a recycled orog…

2020

Skeletal remains in archaeological strata are often assumed to be of similar ages. Here we show that combined Sr and O isotope analyses can serve as a powerful tool for assessing fish provenance and even for identifying fossil fish teeth in archaeological contexts. For this purpose, we established a reference Sr and O isotope dataset of extant fish teeth from major water bodies in the Southern Levant. Fossil shark teeth were identified within Iron Age cultural layers dating to 8–9th century BCE in the City of David, Jerusalem, although the reason for their presence remains unclear. Their enameloid 87Sr/86Sr and δ18OPO4 values [0.7075 ± 0.0001 (1 SD, n = 7) and 19.6 ± 0.9‰ (1 SD, n = 6), res…

Micro-PIXE/PIGE analysis of Palaeolithic mammoth ivory: Potential chemical markers of provenance and relative dating

2014

Abstract Micro-Proton Induced X-ray and Gamma-ray Emission (micro-PIXE/PIGE) provide non-destructive methods for the evaluation of the major, minor and trace element compositions of archaeological material. The current study applies micro-PIXE/PIGE analysis to mammoth ivory artefacts from four Palaeolithic sites (Abri Castanet, Vogelherd Cave, Grottes de la Verpilliere I and II) in France and Germany in order to assess the effectiveness of this approach to material older than 30,000 y BP. It has thus far not been established whether such methods of analysis can yield results of scientific and archaeological interest on ivory material that has undergone such extended periods of diagenesis. T…

The metamorphic rocks of the Nunatak Viedma in the Southern Patagonian Andes: Provenance sources and implications for the early Mesozoic Patagonia-An…

2019

The Nunatak Viedma within the Southern Patagonian Icefield has been considered as a volcanic center based on its geomorphologic features, despite the fact that field explorations by Eric Shipton determined its metamorphic nature 70 years ago. We carried out fieldwork to characterize this isolated outcrop and performed the first U-Pb dating in detrital zircons from the basement rocks located inside the Southern Patagonian Icefield. We recognized very-low grade metamorphic rocks, corresponding principally to metapelites and metapsammites, and scarce metabasites. Detrital zircons in three metapsammitic samples (composite group of 240 grains) yielded prominent age population peaks at ∼1090, ∼96…

Detrital-zircon geochronology and provenance of the El Oro Metamorphic Complex, Ecuador: Geodynamic implications for the evolution of the western Gon…

2019

Abstract The El Oro Metamorphic Complex (EOMC) in SW Ecuador has been the subject of debate for several decades. While previous studies have focused on the metamorphic and deformation history of the complex to determine its geodynamic evolution, the pre-metamorphic history and its association to units in the north-central Andes remains poorly understood. Here we present a U-Pb detrital zircon provenance study to provide insights into the depositional history and the geodynamic setting of the EOMC. Our results imply that the southern portion of the EOMC (the Tahuin division) is composed of an older Palaeozoic (pre-Famatinian) sequence in the south (El Tigre unit; c. 525-510 Ma), and younger …

Microalgae, old sustainable food and fashion nutraceuticals.

2017

8 p.-1 fig.

Take a Trip Through the Plant and Fungal Transportome of Mycorrhiza

2016

International audience; Soil nutrient acquisition and exchanges through symbiotic plant–fungus interactions in the rhizosphere are key features for the current agricultural and environmental challenges. Improved crop yield and plant mineral nutrition through a fungal symbiont has been widely described. In return, the host plant supplies carbon substrates to its fungal partner. We review here recent progress on molecular players of membrane transport involved in nutritional exchanges between mycorrhizal plants and fungi. We cover the transportome, from the transport proteins involved in sugar fluxes from plants towards fungi, to the uptake from the soil and exchange of nitrogen, phosphate, p…

Synthesis of habitat restoration impacts on young-of-the-year salmonids in boreal rivers

2019

River restoration offers the potential to enhance biological integrity, often measured as fish population changes. We used a meta-analytical approach to synthesize density responses to in-stream habitat restoration by young-of-the year (YOY) brown trout and Atlantic salmon in 28 rivers (overall 32 restoration projects) in Finland. We also examined which local and watershed-scale factors most influenced restoration success. Finally, we conducted an expert survey to obtain an independent estimate of a sufficient density enhancement for restoration to be considered successful. Despite strong context-dependency, habitat restoration had an overall positive effect on YOY salmonid density. When co…