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排序方式: 共有323条查询结果,搜索用时 15 毫秒
61.
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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Alzira is situated in a cut-off meander loop of the Rio Júcar. Geo-archaeological study shows that the Islamic city wall was built during the second quarter of the 11th century AD, at a time when the river had a low-amplitude and low-energy flood regime. After mid-century, overbank silts began to invade the city as peak flood discharge increased, with a spate of destructive floods reflected by high-energy deposits during the late 11th century. Urban expansion within the city wall is dated to the later 11th or early 12th century, interrupted by local abandonment and moderate-energy flood silts. Major construction during the mid-12th century was followed by protracted abandonment (after a siege in AD 1171?) and further, moderate-energy flood silts that redistributed occupation and collapse debris. Reoccupation, during the late 14th century, was terminated by catastrophic floods in 1517 and 1571, after which much of the western end of Alzira was not rebuilt. Following further flood catastrophes during the 17th century, parts of the central walled city remained abandoned until the 19th century. with new occupation atop flood sands of yet another disaster in 1864. The change in flood regime after 1150 was a result of deforestation of the watershed, but progradation of a downstream tributary fan after 1517 created an unstable, aggrading floodplain increasingly prone to severe flooding. Climatic anomalies were responsible for periods of recurrent severe floods, archaeologically verified during the 11th and 12th centuries, and historically documented, beginning in 1318. The geo-archaeological methodology illuminates the constructional and settlement history of Alzira, allows distinction of fluvial and cultural components, and provides the necessary microstratigraphic detail and dating control to document the true complexity of alluvial processes during the last 1000 years. 相似文献
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Juan R.I. Cole Nikki R. Keddie William Millward Mehrdad R. Izady 《Iranian studies》1989,22(2-3):189-194
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João Marreiros Juan Gibaja Nuno Bicho 《Archaeological and Anthropological Sciences》2018,10(3):631-645
During the Upper Paleolithic, lithic variability is one of the most important keys to recognize hunter-gatherer behavior, technology, ecology, and social dynamics. The origin and expansion of Gravettian populations in Eurasia has been seen as one of the most critical episodes in human evolution, argued to be the first clear evidence of the so-called polymorphism among modern human populations. In the case of southern Iberian Peninsula, recent data have shown a new regional and diachronic organization for the Gravettian occupation in this region. Therefore, the interpretation of such variability is one of the most important questions, and functional analysis is a fundamental proxy to recognize human technological, settlement and ecological adaptations as major factors for this polymorphism. This study focused on lithic use-wear analysis of the Early Gravettian of Vale Boi (southern Portugal), in order to understand lithic technological organization and variability within and between occupations at the site. Results show similar patterns between assemblages, showing that different materials were worked at the site, although showing reduced time of work, low variability and percentage of pieces used. Unlike other Gravettian contexts in southern Iberia, the Early Gravettian from Vale Boi is characterized by some variability of backed points, marked by the predominance of bipointed double-backed bladelets. Functional analysis of the Early Gravettian lithic industries of Vale Boi provide a new insight to interpret human technology and settlement strategy during the onset of Upper Paleolithic industries in western Eurasia. 相似文献
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山西古村镇类型及社会记忆符号系统研究 总被引:1,自引:0,他引:1
社会记忆是依附于社会群体产生的一种趋同性的社会文化符号。本研究利用结构主义符号学的分析方法,通过“要素体-因子层-属性脉”的三维层次构建社会记忆的符号系统,基于中国传统社会生产、生活方式的视角,从地脉、人脉、文脉的“三脉”属性对古村镇的类型及特征进行解读,发现:①“农”型古村镇社会记忆的宜农宜居、望族乡贤、天人合一的三脉属性符号特征明显;②“商”型古村镇具有对外通达的地脉记忆,精致讲究的文脉记忆和名商名士的人脉记忆;③“军”型古村镇的社会记忆在据险扼要、防御之上、将军传奇的三脉属性特征更加突出;④“工”型古村镇具有矿藏丰富、炉旺风顺、匠人传奇的特色社会记忆的符号特征。 相似文献