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Xabier Pontevedra-Pombal Tim M. Mighall Juan C. Nóvoa-Muñoz Eva Peiteado-Varela José Rodríguez-Racedo Eduardo García-Rodeja Antonio Martínez-Cortizas 《Journal of archaeological science》2013
The analysis of environmental archives from across the world has demonstrated that human perturbation of the geochemical cycles of trace metals and the resultant atmospheric metal contamination date back, at least, several millennia. However, an understanding of the local processes and timing of changes in trace metal deposition is also essential for a proper global interpretation. The Iberian Peninsula was a major mining area since prehistoric times and the analysis of environmental archives provides a good opportunity to improve our understanding of the history of mining and metallurgy in Europe. We present the results from three 14C dated peat cores from the Xistral Mountains (NW Iberia). These records are used to reconstruct past atmospheric deposition of Ni, Zn, As, and Cd. The chronology of the changes in concentrations and metal accumulation rates was found to be concordant in the three bogs, and showed great similarity to total Pb, Hg, and Pb isotope ratios as determined in previous investigations. They present a consistent view of changes in atmospheric pollution and the importance of metals in the development of human societies, especially: i) the first evidence of atmospheric metal pollution 3400 years ago, which is simultaneous with the expansion of the Atlantic Bronze Koine; ii) a pollution event between 2350 and 2150 years ago, associated to the development of so-called Celtic culture (local Late Iron Age); iii) a dramatic increase of metal fluxes in Roman times; iv) a severe and rapid increase in the last 250 years corresponding to the beginning of the industrial revolution in Europe, reflecting the emergence of the new dominant sources of pollution, and v) the increase of long range atmospheric transport of pollutants. Our data suggest that all detected ancient (until ca. 1450 cal BP) periods of enhanced Ni, Zn, As, and Cd accumulation may have had an anthropogenic origin, related to the onset and development of mining and metallurgy. 相似文献
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JOHAN HENRIK SCHREINER. Hellanikos, Thukydides, and the Era of Kimon. Aarhus, Denmark: Aarhus University Press, 1997; dist. Oakville, Conn.: David Brown Book Company. Pp. 135. $26.95 (US); GEORGE CAWKWELL. Thucydides and the Peloponnesian War. London and New York: Roudedge, 1997. Pp. ix, 162. $18.99 (US). Reviewed by Tim Duff 相似文献
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Thomas H. Rich Katarzyna J. Piper David Pickering Sean Wright 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1):133-140
The youngest members of the Ektopodontidae, an enigmatic family of Phalangeroidea, are reported from southwestern Victoria. Four isolated teeth are described as Ektopodon paucicristata sp. nov. (from the ?mid-?late Pliocene, and early Pliocene) and two isolated Pleistocene teeth are assigned to Darcius duggani Rich, 1986. Previously, the youngest known ektopodontid was early Pliocene. 相似文献