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1.
Although characterized by low seismicity, the Monferrato area of north‐western Italy was affected by earthquakes, of magnitude M5.1 and M4.8, in 2000 and 2001. At the same time, marked changes were recorded in water temperature and chemistry in several wells within the epicentral area. In May 2004, an automatic network for the continuous monitoring of groundwater was installed in selected wells to study the phenomenon. Here, we report on data collected during a 3‐year period of groundwater monitoring. During the first year, episodes of water heating (by up to 20°C) were observed in one monitored well. The temporal analysis of the seismic activity recorded in the area revealed as almost all seismic events occurred during the period of elevated water temperatures. The similar timing of earthquakes and groundwater‐temperature anomalies suggests that both may be triggered by the same processes acting in the crust.  相似文献   

2.
傅敏 《安徽史学》2015,(3):100-107
中国代表权问题不仅是美苏为首的两大阵营对抗的最重要的冷战问题之一,而且是美国阵营内部歧见纷呈的问题。朝鲜战争爆发后,维护台湾在联合国的中国代表权符合美国的战略利益,但是英国并不紧随美国的指挥棒合拍地起舞。台湾利用美苏阵营的尖锐对抗,以小搏大,竭力争取美国支持直接否决反对台湾在联合国的中国代表权的方案。台美英三方均有各自的立场与考量,有时限的“缓议案”是三方博弈后的产物。随着美苏阵营对抗的渐趋缓和,台湾当局所能做的必定越来越多的是妥协与退让。  相似文献   

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The concentrations of H2, O2, CO2, and concentrations and isotopic composition of the noble gases (including 222Rn), N2, CH4, and higher hydrocarbons dissolved in 4000 m deep‐seated fluids from a 12‐month fluid production test in the KTB pilot hole were analyzed. This determination of the gas geochemistry during the test in combination with the knowledge of the hydraulic data provides relevant information about the fluid hydraulics of the deep system. All gas concentrations and isotopic signatures, except for 222Rn, showed constancy during the course of the test. This, in combination with large fluid flow rates at a moderate water table drawdown, imply an almost infinite fluid reservoir in 4000 m depth. From the change in 222Rn‐activity as a function of pump rate, the contribution of smaller and wider pores to the overall fluid flow in an aquifer can be deduced. This 222Rn‐activity monitoring proved therefore to be a valuable instrument for the qualitative observation of the scavenging of pore and fracture surfaces, a hydraulic feature invisible to standard hydraulic testing tools. The observance of this scavenging effect is due to (i) the continuous on‐line geochemical monitoring, (ii) the durability of the test, (iii) a change in pump rate during the course of the test, and (iv) due to the short half‐life of 222Rn. The fluids have a 5.9% mantle He component, and a δ21Ne excess of 14%, and a noble gas model age of about (5.5–6.2) ± 2.0 Myr. The mean N2/Ar‐ratio of 516 and δ15N‐data of about +1.5‰ indicates sedimentary or metamorphic origin of N2. The hydrocarbons, amounting to 33 vol.% in the gas phase, are derived from thermal decomposition of marine organic matter of low maturity. But a key question, the identification of the potential source region of the fluids and the migration pathway, is still unidentified.  相似文献   

5.
ABSTRACT In common with Aboriginal groups around Australia, the indigenous people, or Nyungars, of Perth adopt a holistic attitude towards groundwater resources. Of cultural significance are lakes, springs, soaks and watercourses that feature in Dreamtime creation narratives. Perth is experiencing major water shortages and many Nyungars feel that the degradation of the freshwater supply is a result of mismanagement and unsustainable development by non‐Aboriginal people. Proposals for dealing with the issue are seen as equally out of balance with the natural order of things. Water regulators have much to learn from indigenous Australians about water and environmental management. Although water continues to be central to Nyungar identity, the study on which this article is based found evidence of attenuated knowledge about the Dreaming, with discontinuities evident in the way significance is increasingly being read in everyplace rather than in specific ‘story places’.  相似文献   

6.
In recent years, the 'regional scale' within the European Union (EU) has become more central within academic and policy debates. In particular, there has been an increased focus upon the importance of so-called 'institutional thickness' for regional development within the EU. Furthermore, the fact that in several European countries, regionalist political parties have made significant electoral gains has ensured that the 'regional question' in Europe has become even more prevalent. This paper explores the linkages between institutions and regionalist political parties by focusing upon the situation in Italy where the resurgence of political regionalism, centred on the Lega Nord (LN) or Northern League political party, has been particularly strong. In particular, the paper focuses upon the development of the LN in a particular province of Northern Italy, Varese. This section explores the ways in which the LN has developed institutionally and electorally and indeed whether the party has been able to develop a specific political sub-culture to replace the previous one associated with the Christian Democrat (DC) party, which was the main party in Varese before the landmark changes that took place in Italian politics in the early 1990s.  相似文献   

7.
This paper discusses the relationship between agricultural activity and ritualized/religious practices in England from the middle Bronze Age to the early medieval period (c.1500 BC–AD 1086). It is written in the context of the ERC‐funded, Oxford‐based ‘English Landscapes and Identities project’ (EngLaId), which involved the compilation of an extensive spatial database of archaeological ‘monuments’, finds and other related data to chart change and continuity during this period. Drawing on this database alongside documentary and onomastic evidence, we analyze the changing relationship between fields, ritual and religion in England. We identify four moments of change, around the start of the middle Bronze Age (c.1500 BC), in the late Bronze Age (c.1150 BC), the late Iron Age (c.150 BC) and the middle/late Anglo‐Saxon period (c.800 AD). However, despite changes in both agricultural and ritual/religious practices during this extensive timeframe, a clear link between them can be observed throughout.  相似文献   

8.
Recent research in Paleolithic archeology has stressed the importance of temporal issues in assemblage interpretation. Archeological assemblages are temporal constructs, formed by the addition of an unknown number of depositional events. This temporal dimension is also evident at the artifactual level, since single artifacts may undergo different events of modification and/or uses over time. The recycling of previously discarded blanks for tool production is one of the best examples of the temporal nature of artifacts. The aim of this paper is to evaluate the importance of recycling in a Late Upper Paleolithic site, examining a type of artifact – burned tools – that has up to now been little used to approach this issue. Our results suggest that recycling was probably a significant component of Upper Paleolithic provisioning behavior, with important implications in site formation processes and the typological variability of assemblages. The expedient or curated character of recycling is also discussed.  相似文献   

9.
We have made a multivariate morphometric study of the fossils ofMegantereonfrom the Apollonia-1 site at the Mygdonia Basin (Macedonia, Greece), using discriminant functions. Results obtained indicate that these specimens belong to the African speciesMegantereon whiteiBroom, which is also found in the Lower Pleistocene of Dmanisi (East Georgia, Caucasus) and Orce (Southern Spain). Morphofunctional studies ofM. whiteisuggest that this saber-toothed felid was an ambush predator with great killing capability in relation to its food requirements, thus leaving enough meat to be scavenged by both hyaenas and hominids.M. whiteimay have played an important ecological role making the first dispersal ofHomoto Eurasia the Lower Pleistocene possible.  相似文献   

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The water vole, genus Arvicola, is characterised by a broad geographic distribution throughout Europe and is widespread during the late Middle and Upper Pleistocene. This genus is used as a major biostratigraphic tool within the Quaternary. Specific determinations using the Schmelzband-Differenzierung-Quotient or SDQ have identified many chronospecies within the fossil species Arvicola cantiana (Hinton, 1910). As SDQ calculation remains limited, this study reappraises the Arvicola genus in terms of morphodiversity and morphospace using outline analysis which takes into account the tooth as a whole. Outline analysis suggests that one single species of Arvicola, A. cantiana, was present during the Pleistocene. This species shows great variability with no trends or patterns in morphospace. Thus, these results call into question the reliability of SDQ for specific determinations and throw doubt on the biochronological framework based on Arvicola.  相似文献   

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A number of recent papers have argued that summed probability distributions of radiocarbon dates calibrated with the CALPAL software package can be used to identify population trends in prehistory. For instance, Gamble et al. (Gamble, C., Davies, W., Pettitt, P., Richards, M., 2004. Climate change and evolving human diversity in Europe during the last glacial. Philosophical Transactions of the Royal Society of London, Series B 359, 243–254; Gamble, C., Davies, W., Pettitt, P., Richards, M., 2005. The archaeological and genetic foundations of the European population during the Late Glacial: implications for 'agricultural thinking'. Cambridge Archaeological Journal 15, 193–223.) have demonstrated that during the European Late Glacial, demography was more variable than hitherto acknowledged. Building on this work, this paper presents evidence that the large, but so far largely ignored eruption of the Laacher See-volcano, located in present-day western Germany and dated to 12,920 BP, had a dramatic impact on forager demography all along the northern periphery of Late Glacial settlement and precipitated archaeologically visible cultural change. In Southern Scandinavia, these changes took the form of technological simplification, the loss of bow-and-arrow technology, and coincident with these changes, the emergence of the regionally distinct Bromme culture. Groups in north-eastern Europe appear to have responded to the eruption in similar ways, but on the British Isles and in the Thuringian Basin populations contracted or relocated, leaving these areas largely depopulated already before the onset of the Younger Dryas/GS-1 cooling. Demographic models are used to link these changes to the Laacher See-eruption and this research demonstrates that we cannot sideline catastrophic environmental change in our reconstructions of prehistoric culture history.  相似文献   

14.
The elemental fluxes and heat flow associated with large aquifer systems can be significant both at local and at regional scales. In fact, large amounts of heat transported by regional groundwater flow can affect the subsurface thermal regime, and the amount of matter discharged towards the surface by large spring systems can be significant relative to the elemental fluxes of surface waters. The Narni‐Amelia regional aquifer system (Central Italy) discharges more than 13 m3 sec?1 of groundwater characterised by a slight thermal anomaly, high salinity and high pCO2. During circulation in the regional aquifer, groundwater reacts with the host rocks (dolostones, limestones and evaporites) and mixes with deep CO2‐rich fluids of mantle origin. These processes transfer large amounts of dissolved substances, in particular carbon dioxide, and a considerable amount of heat towards the surface. Because practically all the water circulating in the Narni‐Amelia system is discharged by few large springs (Stifone‐Montoro), the mass and energy balance of these springs can give a good estimation of the mass and heat transported from the entire system towards the surface. By means of a detailed mass and balance of the aquifer and considering the soil CO2 fluxes measured from the main gas emission of the region, we computed a total CO2 discharge of about 7.8 × 109 mol a?1 for the whole Narni‐Amelia system. Finally, considering the enthalpy difference between infiltrating water and water discharged by the springs, we computed an advective heat transfer related to groundwater flow of 410 ± 50 MW.  相似文献   

15.
Strontium isotope ratio analysis of human dental enamel and bone is applied to investigate a highly debated question of population movement and cultural discontinuity in Prehistoric Aegean Archaeology. The Late Minoan IB (ca. 1490/1470 BC) destructions on Crete are succeeded by cultural upheaval. The novel cultural features that appear at Knossos (Crete) in this period have forerunners in the Mainland. In Cretan context, the Linear B writing system, the funerary architecture and burial practices of the Mainland style are interpreted as evidence of an actual “Mycenaean” long-term settlement and political domination of Knossos. Human skeletal material from tombs that are associated with non-locals from the Mainland based upon the material culture is analysed to measure 87Sr/86Sr. The results of the analysis show that all the examined individuals from the Knossos tombs were born locally.  相似文献   

16.
Radiocarbon and U-series methods (230Th/U and 231Pa/235U) for absolute age determination have been applied to some fossil samples from Grotta Juntu, in North Eastern Sardinia (Italy). The remains belong to the endemic deer species Praemegaceros cazioti, which is here represented by an almost complete skeleton. The three dating methods lead to concordant ages of about 7500 years BP, indicating that the skeleton was maintained as closed system after burial. Taking into consideration these results, Praemegaceros cazioti from Grotta Juntu is now the youngest representative of this species in Sardinia.  相似文献   

17.
X‐ray fluorescence (XRF), X‐ray diffraction (XRD) and Raman spectroscopy were employed to analyse the chemical compositions and phase structures of nine pieces of jade artefacts unearthed from Sujiacun, a Longshan Culture (2400–2000 bce ) site in coastal Shandong, eastern China. The results of the analyses indicated these samples were primarily made from multiple raw mineral materials, including antigorite, actinolite, clinochlore, turquoise and muscovite. No nephrite was recovered from the Sujiacun site. This is strikingly different from other top‐ranking settlements of Longshan Culture, such as Dantu, Liangchengzhen and Xizhufeng, in which nephrite was the main material of jade artefacts. This may reflect the distinctions in the supply system of jade raw materials among different rankings of Longshan period sites. In addition, laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) was used to analyse the composition of the rare earth elements of serpentine jade. These preliminary results were compared with published data on the composition of serpentine jade and it was found that the Sujiacun serpentine jade artefacts were likely sourced from the Taishan jade deposit.  相似文献   

18.
The Upper Palaeolithic skeleton from Vado all'Arancio (Italy), dated to about 11,330 BP, exhibits a severe ankle fracture healed with residual deformation. Following recovery, this young hunter‐gatherer continued to walk for an extended period of time, albeit in a mechanically altered manner. While right‐left differences in external lower limb bone measurements are relatively low, biomechanical analysis of femur and tibia indicates unusually pronounced asymmetry in all cross‐sectional measures of diaphyseal strength. Asymmetry results primarily from normal side endosteal hypertrophy, and not from hypotrophy of the injured limb, suggesting that this individual resumed active life following recovery. This pattern of asymmetry underscores the role of physical activity in maintaining bone mass. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

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Certain trace elements may accumulate in bone in relation to dietary habits, so some of them are of interest in paleodietary analysis. This is the case with strontium (Sr) and barium (Ba), whose potential value as paleodietary indicators is enhanced by their relatively inert metabolic behaviour. The presence of carious lesions may indicate consumption of sugar and vegetables, whereas the etiology of dental calculus deposition is multifactorial, although some authors consider this as an indicator of protein consumption. Based on these facts we analysed (1) Ba, Sr, and calcium (Ca) content of inner cortical bone obtained from the ramus mandibularis, by atomic absorption spectrophotometry, (2) presence of teeth with carious lesions, and (3) presence of teeth with calculus deposition in 62 mandibles. All samples were obtained from the church La Concepción, an 18th century burial place in Tenerife. Gender was assessed by analysing genetic expression of amelogenin in some cases (14), and by inspection of pelvic bones when available (41 cases). We found (1) Carious lesions in 32 cases, and dental calculus, in 39; no association was observed between sex and presence of dental caries or calculus deposition, nor between the sex and the proportion of carious teeth nor the proportion of teeth with calculus deposition; (2) people buried near the altar (priests and individuals of the highest social class) showed a significantly higher proportion of teeth with dental calculus deposition (χ2 = 5.36, p = 0.021); (3) bone Sr and bone Ba were significantly higher than the values observed in a control group of 10 modern omnivorous individuals; the lowest Sr values were observed among people buried near the altar; and (4) the Ba/Sr ratio was directly related with the proportion of teeth with carious lesions. These data suggest that there were differences in dietary pattern among the individuals belonging to different social classes; overall, consumption of vegetables was widespread, as shown by the high proportion of carious lesions, in relation with raised Ba/Sr ratio, whereas consumption of marine products was scarce.  相似文献   

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