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1.
As part of a preliminary geological characterization programme to assess the feasibility of an underground laboratory in granitic rock, a series of 17 deep boreholes (maximum depth, 900 m) was drilled by ANDRA in the Vienne district, France. A salinity gradient was demonstrated in the granitic waters with concentrations varying from approximately 1 g L?1 at 150 m depth at the top of the basement (beneath the sedimentary cover) to 10 g L?1 in the deeper part (from 400 to 600 m depth). Sr and B isotope ratios were measured in order to better understand the origin of the salinity and to evaluate the degree of water–rock interaction in the system. The results obtained were compared to those of mineral spring waters emerging from the granitic basement in the Massif Central. Evidence in support of a significant marine contribution include: (i) the Cl–Br investigations agree with a marine origin for the saline groundwaters without evolution from seawater; (ii) the 87Sr/86Sr ratio of the Vienne deep groundwaters (0.7078–0.7084) is in agreement with a palaeo‐seawater isotopic signature; (iii) measured δ11B values for the deepest brine samples are enriched in 11B (up to 36.1‰) relative to the granitic springs. The combined use of δ11B, Cl, B, Br, Sr contents and 87Sr/86Sr ratios makes it possible to define and quantify a mixing model between marine and crustal end‐members in order to explain the origin of the deep saline groundwaters in the Vienne granitic rocks.  相似文献   

2.
The relationship between fracturing and fracture filling in opening‐mode fractures in the Triassic Buntsandstein in the Lower Saxony Basin (LSB; NW Germany) has been studied by an integration of petrographic and structural analysis of core samples, strontium isotope analysis and microthermometry on fluid inclusions. This revealed the relationship between the timing of the fracturing and the precipitation of different mineral phases in the fractures by constraining the precipitation conditions and considering the possible fluid transport mechanisms. The core was studied from four different boreholes, located in different structural settings across the LSB. In the core samples from the four boreholes, fractures filled with calcite, quartz and anhydrite were found, in addition to pore‐filling calcite cementation. In boreholes 2 and 3, calcite‐filled fractures have a fibrous microstructure whereas in borehole 1, fractures are filled with elongate‐blocky calcite crystals. Anhydrite‐filled fractures have, in all samples, a blocky to elongate‐blocky microstructure. Fractures that are filled with quartz are observed in borehole 2 only where the quartz crystals are ‘stretched’ with an elongated habit. Fluid inclusion microthermometry of fracturing‐filling quartz crystals showed that quartz precipitation took place at temperatures of at least 140°C, from a fluid with NaCl–CaCl2–H2O composition. Melting phases are meta‐stable and suggest growth from high salinity formation water. Strontium isotopes, measured in leached host rock, indicate that, in boreholes 2 and 3, the fluid which precipitated the calcite cements and calcite‐filled fractures is most likely locally derived whereas in borehole 1, the 87Sr/86Sr ratios from the pore‐filling cements and in the elongate‐blocky calcite‐filled fracture can only be explained by mixing with externally derived fluids. The elongate‐blocky anhydrite‐filled fractures, present in boreholes 1, 3 and 4, precipitated from a mixture of locally derived pore fluids and a significant quantity of fluid with a lower, less radiogenic, 87Sr/86Sr ratio. Taking into account the structural evolution of the basin and accompanying salt tectonics, it is likely that the underlying Zechstein is a source for the less radiogenic fluids. Based on the samples in the LSB, it is probable that fibrous fracture fillings in sedimentary rocks most likely developed from locally derived pore fluids whereas elongate‐blocky fracture fillings with smooth walls developed from externally derived pore fluids.  相似文献   

3.
Human skeletons were recovered in two unmarked burials blown to the surface of a dune south‐west of Jebel al‐Emeilah in the Central Region of the Sharjah Emirate (UAE). Sasanian stamp seals were found associated with one of the individuals. A bone fragment of this individual provided a direct radiocarbon date placing it in the Middle Sasanian period. With the aid of strontium isotope analysis it was possible to determine that the two individuals were immigrants to the area that is now part of the UAE.  相似文献   

4.
Saltpetre constitutes one of the major ingredients of gunpowder, which was a driving force during the political changes in late medieval to early modern times in Japan. Two types of model saltpetre mineralization are studied. One represents efflorescent saltpetre formed as the byproduct of indigo dye manufacture, whereas the second is anthropogenic, derived from relict nitre‐beds. Here, oxygen and nitrogen isotopic analysis, as expressed by δ18O and δ15N notations, is applied. The calculated δ18O values for ambient water, responsible for the microbial‐mediated oxidation of ammonium into oxygen in nitrates, tended to have higher ranges than average local meteoric waters of the relevant regions. An overall trend could be seen, showing the apparent positive nitrogen isotopic fractionation during the microbial transformation from initial organic nitrogen into nitrate product. Dual isotopic analysis for industrial nitrates provides a useful tool for investigation of the provenance of historic gunpowder. Present anthropogenic saltpetre involves positive control over temperature–moisture regimes and oxygen fugacity during formation, the process being distinctive from those prevailed in British India and other European countries.  相似文献   

5.
The secondary production (working) of glass from imperial to early Byzantine times has been proven at the ancient city of Sagalassos (SW Turkey) by the existence of glass chunks, fuel ash slag and kiln fragments related to glass processing. It had been previously suggested that local green glass might have been recycled from two other locally found glass types (blue glass vessels and chunks and HIMT glass chunks). This paper provides analytical evidence for the recycling of glass next to the use of imported raw glass. The heterogeneous lead isotopic composition of the green and HIMT vessel glass at Sagalassos, with as end members on the one hand the isotopic composition of local blue glass vessels and chunks and on the other hand that of the HIMT glass chunks, could indicate the production of ‘recycled’ glass, although heterogeneous raw materials could have been used. However, the use of Sr-mixing lines confirms local recycling. It is clear that the Sr in the green and HIMT vessels is a mixture of the Sr in the aforementioned end members. It cannot be proved whether the green ‘recycled’ glass was produced from a mixture of chunks alone, or from a mixture of cullet and chunks. Suggestions are made towards the possible origin of the raw materials for the blue and HIMT glass on the basis of Sr isotopic signatures and absolute Sr contents in the glass.  相似文献   

6.
Human skeletal remains from the Neolithic sites BHS18 in the interior of the Sharjah Emirate and the Neolithic shell midden UAQ2 (Umm al‐Quwain) on the coast of the Persian Gulf (United Arab Emirates, UAE) were analysed for their isotope ratios of strontium (87Sr/86Sr) and oxygen (18O/16O). The results are not in agreement with earlier assumptions about a Neolithic nomadism between inland regions and the south‐eastern coast of the Persian Gulf. Existing evidence of nomadic movements of the people from BHS18 most possibly refers to transhumance within the mountains in the hinterland. The strontium isotope measurements on human skeletons from UAQ2 on the contrary indicate uninterrupted residence of this population on the coast. Nevertheless, evidence was found of individual mobility between inland regions and the coast.  相似文献   

7.
Bioarchaeology and biogeochemistry can elucidate aspects of individual life histories that are often lost in the archaeological record. Here, we use stable and radiogenic isotope analyses of enamel, bone and hair to reconstruct paleodiet and paleomobility in an adult male interred along a pre‐Columbian route connecting the northern Chilean coast to the inland Loa River Valley. Although this well‐preserved burial included mortuary goods typical of coastal cultures, it was discovered in a vast, uninhabited part of northern Chile's hyper‐arid Atacama Desert. Variation in carbon and nitrogen isotopes reflects dietary differences, while strontium and oxygen isotopes vary geologically and geographically. We use these data to examine paleodiet and paleomobility and to assess whether this was a coastal traveller seeking provisions from the interior or vice versa. Enamel stable isotope analysis is consistent with the consumption of a mixture of terrestrial and marine resources during the first years of life. Bone stable isotope analyses indicate habitual consumption of marine foodstuffs over the last 10–30 years of this individual's life. Interestingly, stable isotope analysis of hair samples provides more fine‐grained information on this individual, suggesting movements between the coast and highlands in the months before his death. Radiogenic strontium isotope data are consistent with residence on the coast or in the Atacama Desert, but are lower than strontium isotope values from higher altitudes. These dietary and geological patterns are reconcilable with coastal residency; the isotopic data are consistent with foodstuffs and textiles found with the burial. Therefore, we argue that this individual was regularly moving from the coast to inland areas, crossing the hyper‐arid Atacama Desert by following strategic interzonal routes that provided access to particular resources. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

8.
We analyzed stable carbon and nitrogen isotope ratios of human and animal remains from the Ando shell midden, South Korea. The Ando site is a rare Incipient Chulmun (Neolithic) site (ca. 6000–5000 BC), which contains well-preserved human and animal bones in shell mounds. The stable isotope results for humans (average δ13C = −13.5 ± 0.5‰ and δ15N = 15.2 ± 0.5‰) indicate that Ando people in the Incipient Chulmun period strongly depended on marine resources. There were no isotopic differences between humans of different sex and age at this site. We compared our data with other previous published isotopic data from the Chulmun sites and found that the Ando people had similar isotope values to the southern Chulmun people (Tongsamdong and Daepo), but different isotopic ratios than the western Chulmun people (Daejukri and Konamri). These results indicate that marine foods were the main food resources in the southern coastal regions, but not in the western coastal regions in Chulmun Korea.  相似文献   

9.
The Finnish student magazine Ylioppilaslehti has been an important publication in the Finnish public sphere. This article studies the role of Ylioppilaslehti in creating the Finnish public sphere in the post-war decades. On the one hand, this was a period in which the political position of Finland was unstable, but, on the other, the students experienced ‘a hunger for culture’. The article is also interested in what role Ylioppilaslehti played in creating the Finnish elite. The magazine is an institution, which has been an arena for the Finnish cultural and political elite throughout the 20th century, and the 1950s was a particularly significant period for its participation in the Finnish process of social construction.  相似文献   

10.
Studies of the relationship between the strontium content of human bone and past diet are still in an experimental stage. Because of the low frequency of carnivore remains at most archaeological sites and the absence of information on local strontium levels, it has been difficult to (1) estimate dietary intake for a prehistoric population, and (2) to compare prehistoric populations from spatially disparate areas. However, examination of strontium/calcium ratios in a modern herbivore may help to alleviate these problems. Bones from modern white-tailed deer (Odocoileus virginianus) were compared with deer diet in Wisconsin. An observed ratio between deer bone and diet in terms of a strontium/calcium index was calculated at 0204, which compares favourably with observed ratios reported for other mammals. Prehistoric white-tailed deer are used in the analysis of two Late Archaic sites in the midwestern U.S.A. The strontium levels in deer can be used as a baseline for comparison between sites. The prehistoric subsistence patterns are generally comparable, with hunting accounting for the bulk of the diet.  相似文献   

11.
Yelang (夜郎), a mysterious state located in the south‐western area of early China and dating from the Bronze Age to the Early Iron Age (1300 bc – ad 25), is a cultural interactive junction between the Yunnan–Guizhou Plateau and the Yangtze River Basin. The Zhongshui Basin in Weining County, Guizhou Province, was one of the important distribution areas of the Yelang civilization. This area, which includes sites at Jigongshan (鸡公山; 1300 – 800 bc ), Hongyingpan (红营盘; 700 – 400 bc ) and Yinzitan (银子坛; 400 bc – ad 25), has provided a very integrated chronology, spanning from the Bronze Age to the Early Iron Age in the eastern Yunnan – western Guizhou area. To investigate human migration and horse‐trading at these Yelang sites, we conducted a strontium isotopic analysis on the teeth enamel of humans and horses unearthed from these three sites. The results indicated the following: (1) people at the earlier sites (Jigongshan and Hongyingpan) were all indigenous, whereas in the Yinzitan cemetery, there was a more immigrant population, and all the people who were buried in an upper limb flexed supine position were non‐local; and (2) most of the horses found at the Jigongshan and Yinzitan sites show different provenances, probably related to the famous Dian (滇) and Zuo (筰) horses recorded in historical documents, providing more clues for further study on horse‐trading in South‐West China during the Bronze Age and the Early Iron Age.  相似文献   

12.
K. LI  C. CAI  H. HE  L. JIANG  L. CAI  L. XIANG  S. HUANG  C. ZHANG 《Geofluids》2011,11(1):71-86
Petrographic features, isotopes, and trace elements were determined, and fluid inclusions were analyzed on fracture‐filling, karst‐filling and interparticle calcite cement from the Ordovician carbonates in Tahe oilfield, Tarim basin, NW China. The aim was to assess the origin and evolution of palaeo‐waters in the carbonates. The initial water was seawater diluted by meteoric water, as indicated by bright cathodoluminescence (CL) in low‐temperature calcite. The palaeoseawater was further buried to temperatures from 57 to 110°C, nonluminescent calcite precipitated during the Silurian to middle Devonian. Infiltration of meteoric water of late Devonian age into the carbonate rocks was recorded in the first generation of fracture‐ and karst‐filling dull red CL calcite with temperatures from <50°C to 83°C, low salinities (<9.0 wt%), high Mn contents and high 86Sr/87Sr ratios from 0.7090 to 0.7099. During the early Permian, 87Sr‐rich hydrothermal water may have entered the carbonate rocks, from which precipitated a second generation of fracture‐filling and interparticle calcite and barite cements with salinities greater than 22.4 wt%, and temperatures from 120°C to 180°C. The hydrothermal water may have collected isotopically light CO2 (possibly of TSR‐origin) during upward migration, resulting in hydrothermal calcite and the present‐day oilfield water having δ13C values from ?4.3 to ?13.8‰ and showing negative relationships of 87Sr/86Sr ratios to δ13C and δ18O values. However, higher temperatures (up to 187°C) and much lower salinities (down to 0.5 wt%) measured from some karst‐filling, giant, nonluminescent calcite crystals may suggest that hydrothermal water was deeply recycled, reduced (Fe‐bearing) meteoric water heated in deeper strata, or water generated from TSR during hydrothermal water activity. Mixing of hydrothermal and local basinal water (or diagenetically altered connate water) with meteoric waters of late Permian age and/or later may have resulted in large variations in salinity of the present oilfield waters with the lowest salinity formation waters in the palaeohighs.  相似文献   

13.
The management and conservation of animal species should be based upon a long-term analysis that considers its geographical distribution and feeding patterns. The study of carbon and nitrogen stable isotopes on skeletal remains provides a quantitative approach to the paleodietary reconstructions and constitutes a potent tool for comparing behavioral aspects of the fauna. In this paper we present the first set of isotopic values for modern and archaeological samples of Huemul (Hippocamelus bisulcus) from the forests of Central-western Patagonia, Chile. Contrary to initial expectations, our analysis indicates that there is no evidence of an important incidence of the canopy effect on the δ13Ccollagen values, which we suggest is due to an ecological selection that drives the huemul to focus its predation on open sectors within the forest. On the other hand, a wide range of δ15Ncollagen values for huemul was verified. This could reflect the N impoverishment of the forest soils and provide an interesting ecological indicator. The long-term information offered by the archaeological record provides the necessary context for decision-making conducive towards the preservation of Hippocamelus bisulcus in Patagonia.  相似文献   

14.
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   

15.
The reasons why the Western Mediterranean, especially Carthage and Rome, resisted monetization relative to the Eastern Mediterranean are still unclear. We address this question by combining lead (Pb) and silver (Ag) isotope abundances in silver coinage from the Aegean, Magna Graecia, Carthage and Roman Republic. The clear relationships observed between 109Ag/107Ag and 208Pb/206Pb reflect the mixing of silver ores or silver objects with Pb metal used for cupellation. The combined analysis of Ag and Pb isotopes reveals important information about the technology of smelting. The Greek world extracted Ag and Pb from associated ores, whereas, on the Iberian Peninsula, Carthaginians and Republican‐era Romans applied Phoenician cupellation techniques and added exotic Pb to Pb‐poor Ag ores. Massive Ag recupellation is observed in Rome during the Second Punic War. After defeating the Carthaginians and the Macedonians in the late second century bce , the Romans brought together the efficient, millennium‐old techniques of silver extraction of the Phoenicians, who considered this metal a simple commodity, with the monetization of the economy introduced by the Greeks.  相似文献   

16.
The boron stable isotope ratio δ11B of 12 water samples representative of three chemical facies (fresh Na‐bicarbonate, brackish Na‐chloride, saline, and brine Ca‐chloride) has been analyzed. Interpretation of the δ11B data, along with the chemical compositions, reveals that Na‐carbonate waters from the Northern Apennine are of meteoric origin, with boron contributions from clay desorption and mixing with seawater‐derived fluids of Na‐chloride or Ca‐chloride compositions. The comparison of our new results with the literature data on other sedimentary basins of Mediterranean, and worldwide, confirms the contribution of Na‐bicarbonate waters to the genesis of mud volcano fluids. The Na‐chloride sample of Salvarola (SAL), which may represent the end‐member of the mud volcanoes, and the Ca‐chloride brine water from Salsomaggiore (SM) indicate boron release from clays compatible with the diagenetic process. The empirical equation: relating boron concentration and the stable isotope composition of the fluids observed in this study and the literature is proposed to trace the effect of diagenesis in sedimentary basins. A geothermometer associated to the diagenetic equation is also proposed: The application of this equation to obtain reservoir temperatures from δ11B compositions of waters should be carefully evaluated against the results obtained from other chemical and isotopic geothermometers from other basins around the world.  相似文献   

17.
ABSTRACT In this paper an attempt is made to measure the cultural industries in a cross‐national context. The paper starts with a discussion of the definition and delineation of the term the ‘cultural industries’. It is argued that a large range of goods and services may be considered to be cultural industry products and that it is important to place the production and exchange of such products in the context of an industrial systems approach. Following this the concept is operationalised using data on employment and firm activity from Denmark, Finland, Norway and Sweden. Results are presented which suggest that overall growth in both employment and firm numbers has been especially strong in the cultural industries. However, interesting differences between the countries emerged from the data. Thus regional dimensions are then examined resulting in the finding that in all four countries cultural industries have a strong attraction to urban areas but an even stronger propensity to agglomerate. It is suggested that the spatial dynamics observed may be key to the development of the industries' competencies and success. In summary the paper presents results of extensive data analysis that show the cultural industries' important contribution to Scandinavian economies and labour markets.  相似文献   

18.
Organic fertilizers have the capacity to alter the nitrogen isotopic composition of plants. Camelid dung and seabird guano are two potentially important fertilizers in the agricultural systems of western South America, particularly Peru and Chile. This paper presents isotopic data (δ13C and δ15N) from field grown plants (maize, Zea mays) fertilized with the following four treatments: CO (control, no fertilizer applied), AS (ammonium sulfate, a chemical fertilizer), DU (camelid dung), and SG (seabird guano). Plants were grown in experimental plots in the Virú Valley, northern Peru. Plants fertilized with the chemical fertilizer presented very similar isotopic compositions compared to the control. Conversely, the camelid dung fertilized plants were characterized by higher δ15N values compared to the control plants (by 1.8 to 4.2‰ depending on the plant part). The seabird guano fertilized plants were greatly enriched in 15N in comparison to the control plants (by 11.3 to 20.0‰). The results of this study have important implications for the reconstruction of human diet using isotopic data derived from bone collagen and related tissues, particularly in the prehispanic Andes, but also in Europe and North America during the 19th century, when Peruvian seabird guano was used extensively. Specifically, the interpretation of the relative contributions of plant and animal protein to the diet on the basis of bulk isotopic compositions of bone collagen (or similar tissues) may be confounded by camelid dung fertilization if the carbon isotopic compositions of the two sources are similar. Likewise, the interpretation of the relative contributions of maize and marine protein may be confounded by seabird guano fertilization.  相似文献   

19.
The carbon and oxygen isotopic composition of the mineral phase of tooth enamel is linked to diet and environment. Enamel is not remodelled once formed. Several studies of intra‐tooth isotopic variability in hypsodont mammal teeth have involved sequential sampling of enamel in order to detect changes in diet and environment during tooth formation. The possibility of exploring individual history opens the door to many applications, particularly in palaeoenvironment and herd management reconstruction. However, previous histological investigations have shown that enamel mineralization is a progressive and discontinuous process. The goal of the present study is to determine if this pattern significantly influences the time resolution of an intra‐tooth sequential sampling. Isotopic analyses (δ13C) were performed on tooth enamel from steers (Bos taurus) that had changed from a C3 plant‐based diet to a C4 plant‐based diet with very different carbon isotopic compositions. The change of diet was reflected in the mineral phase of enamel. The pattern of intra‐tooth isotopic variation suggests that completion of enamel mineralization required six to seven months. Such a lag in enamel mineralization will decrease the time resolution of enamel sequential sampling. The effects of prolonged mineralization of enamel have to be considered when interpreting patterns of intra‐tooth isotopic variations. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

20.
Recently, a new program of territorial study was launched in the area of Wadi Takarkori (Wadi Takarkori Project, hereafter WTP), located in south-western Libya at the border with Algeria in a strategic position between the Tassili and Acacus Mountains. The core of this program was the excavation of a rock shelter together with the systematic mapping and selected excavations of stone structures in the wadi area, mainly tumuli, a typical Saharan feature.  相似文献   

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