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Burgos, Spain

Gomez-Olivencia A.,University of the Basque Country | Gomez-Olivencia A.,Ikerbasque | Gomez-Olivencia A.,French Natural History Museum | Gomez-Olivencia A.,Complutense University of Madrid | And 9 more authors.
Quaternary Science Reviews | Year: 2015

The period between the end of the Early Pleistocene and the mid-Middle Pleistocene (roughly between 1.0 and 0.4MaBP) is of great interest in Western Europe. It witnessed several climatic oscillations and changes in the fauna, the demise of a hominin species and the appearance of another, along with important cultural and technological changes. Thus, the few available sites with these chronologies is vital to the understanding of the tempo and mode of these changes. Middle Pleistocene sites in the Northern Iberian Peninsula are very rare. Here we present the study of the site found at the Punta Lucero Quarry (Biscay province, Northern Iberian Peninsula), which includes for the first time the complete collection from the site. The fossil association from this site includes several ungulates, such as a Megacerine deer, Cervus elaphus, large bovids (likely both Bos primigenius and Bison sp. are present), Stephanorhinus sp., and carnivores, such as Homotherium latidens, Panthera gombaszoegensis, Canis mosbachensis and Vulpes sp. This association is typical of a middle Middle Pleistocene chronology and would be the oldest macro-mammal site in the Eastern Cantabrian region. This site would likely correspond to a chronology after Mode 1 technological complex and before the arrival of Mode 2 technology in this region. Thus, it offers a glimpse into the paleoecological conditions slightly prior to or contemporaneous with the first Acheulian makers in the northern fringe of the Iberian Peninsula. © 2015 Elsevier Ltd.

Constantin S.,The Emil Racovita Institute of Speleology | Robu M.,The Emil Racovita Institute of Speleology | Munteanu C.-M.,The Emil Racovita Institute of Speleology | Petculescu A.,The Emil Racovita Institute of Speleology | And 9 more authors.
Quaternary International | Year: 2014

The Urşilor Cave (NW Romania) is a famous cave bear paleontological site hosting an important Late Pleistocene faunal assemblage and subject to systematic excavation works. To better understand the origin of fossil assemblages, the sedimentary history of the cave must be reconstructed. We conducted a series of investigations on various cave deposits which included sedimentology and grain-size analyses, U-series dating of speleothems, OSL dating of sediments, and AMS radiocarbon dating of fossil remains. The results allowed for the identification of several major chronological controls for the evolution of the cave during the last 300,000 years. Five evolutionary stages or key-moments were dated, and a tentative speleogenetic scenario is presented. The combined numerical dates and sedimentological study show that the evolution of the cave was more complex than previously thought. In particular, the fossil accumulation was related to a succession of rapid flooding events at ~47-40ka. Alternating depositional and erosional phases have occurred since at least 210ka complicating the sediment structures. The results suggest that the upper and lower levels of the cave may have been functioned occasionally as hydrologically separated karst systems and that the animal populations from what is now a single cave system may not necessarily be synchronous. This case study shows that reconstructing sedimentary history of a given cave is crucial for the correct understanding of its thanatocenosis. © 2013 Elsevier Ltd and INQUA.

Scholz D.,University of Mainz | Hoffmann D.L.,CENIEH | Hoffmann D.L.,University of Bristol | Hellstrom J.,University of Melbourne | Bronk Ramsey C.,University of Oxford
Quaternary Geochronology | Year: 2012

Speleothems, such as stalagmites and flowstones, can be dated with unprecedented precision in the range of the last 650,000 a by the 230Th/U-method, which is considered as one of their major advantages as climate archives. However, a standard approach for the construction of speleothem age models and the estimation of the corresponding uncertainty has not been established yet.Here we apply five age modelling approaches (StalAge, OxCal, a finite positive growth rate model and two spline-based models) to a synthetic speleothem growth model and two natural samples. All data sets contain problematic features such as outliers, age inversions, large and abrupt changes in growth rate as well as hiatuses.For data sets constrained by a large number of ages and not including problematic sections, all age models provide similar results. In case of problematic sections, the algorithms provide significantly different age models and uncertainty ranges.StalAge, OxCal and the finite positive growth rate model are, in general, more flexible since they are capable of modelling hiatuses and account for problematic sections by increased uncertainty. The spline-based age models, in contrast, reveal problems in modelling problematic sections.Application to the synthetic data set allows testing the performance of the algorithms because the 'true' age model is available and can be compared with the age models. OxCal and StalAge generally show a good performance for this example, even if they are inaccurate for a short section in the area of a hiatus. The two spline-based models and the finite positive growth rate model show larger inaccurately modelled sections. © 2012 Elsevier B.V.

Turrero M.J.,CIEMAT | Garralon A.,CIEMAT | Sanchez L.,CIEMAT | Ortega A.I.,CENIEH | And 3 more authors.
Environmental Earth Sciences | Year: 2015

Drip-water chemistry in karstic caves can vary at seasonal to interannual scales in response to climatic factors such as temperature, rainfall, and seasonality, which determine changes in the hydrological and hydrochemical processes of the percolating waters in their paths from the atmosphere to the cave. In this paper the characterization of stalagmite forming drip-waters based on longterm (years) time-series data is presented as a key task for understanding the geochemical behavior of a specific system, the Kaite Cave (N Spain). The work focuses on the relationships between rainfall, drip rates, drip-water calcium concentration, and drip-water trace elements amount (e.g., Mg and Sr); as indicators of hydrologic processes defining the karst system and controlling speleothem growth and composition patterns. © Springer-Verlag Berlin Heidelberg 2015.

Rodriguez J.,CENIEH | Mateos A.,CENIEH | Martin-Gonzalez J.A.,University of Burgos | Rodriguez-Gomez G.,CENIEH
Quaternary International | Year: 2015

Beneath the hot debate about the tempo and mode of the first human colonization of Europe is the perception that the record of human presence in the Early Pleistocene is sparse and fragmented. As a result, it is often implicitly assumed that hominins, if present, were scarce in the Early Pleistocene European ecosystems. Here we present a quantitative assessment of the rarity and commonness of the European large mammal species during the 1.4-0.8. Ma period, including hominins. Considering the palaeontological record only, Homo was not one of the most common species in Europe, but it may not be considered a rare species. In contrast, taking into consideration the archaeological record, hominins exhibit a wide geographical distribution and a high frequency of occurrence (occupancy) in comparison with other large mammals. It is speculated that hominins were frequent but not abundant in Europe during the late Early Pleistocene. © 2015 Elsevier Ltd and INQUA.

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