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1.
Most researchers in the Proterozoic eastern Mt Isa Block, NW Queensland, Australia, favour magmatic fluid and salt sources for sodic‐(calcic) alteration and iron oxide–copper–gold mineralization. Here we compare spatial, mineralogic and stable isotope data from regional alteration assemblages with magmatic and magmatic‐hydrothermal interface rocks in order to track chemical and isotopic variations in fluid composition away from inferred fluid sources. Tightly clustered δ18O values for magnetite, quartz, feldspar and actinolite for igneous‐hosted samples reflect high temperature equilibration in the magmatic‐hydrothermal environment. In contrast, these minerals record predominantly higher δ18O values in regional alteration and Cu–Au mineralization. This dichotomy reflects partial equilibration with isotopically heavier wallrocks and slightly lower temperatures. Increases in Si concentrations of metasomatic amphiboles relative to igneous amphiboles in part reflect cooling of metasomatic fluids away from igneous rocks. Variations in XMg for metasomatic amphiboles indicate local wallrock controls on amphibole chemistry, while variations in XCl/XOH ratios for amphiboles (at constant XMg) indicate variable aH2O/aHCl ratios for metasomatic fluids. Biotite geochemistry also reflects cooling and both increases and decreases in aH2O/aHCl for fluids away from plutonic rocks. Decreased aH2O/aHCl ratios for metasomatic fluids reflect in part scavenging of chlorine out of meta‐evaporite sequences, although this process requires already saline fluids. Local increases in aH2O/aHCl ratios, as well as local decreases in δ18O values for some minerals (most notably haematite and epithermal‐textured quartz), may indicate ingress of low salinity, low δ18O fluids of possible meteoric origin late in the hydrothermal history of the region. Taken together, our observations are most consistent with predominantly magmatic sources for metasomatic fluids in the eastern Mt Isa Block, but record chemical and isotopic variations along fluid flow paths that may be important in explaining some of the diversity in alteration and mineralization styles in the district.  相似文献   

2.
In the prehispanic Gran Canaria there are some anthropological differences between the coastal inhabitants who buried their dead mainly in tumuli, and those from the central mountains, mainly buried in caves. Some data, as the prevalence of auricular exostoses, and a different bone Ba/Sr ratio support the view that there were differences in economy and diet between both groups of islanders. Moreover, the proportion of carious teeth was significantly higher among the population buried in caves. In the present study we analysed the prevalence of dental calculus, periodontal disease and antemortem tooth loss in remains of 791 individuals belonging to the anthropological collection of the Museo Canario (Las Palmas). Calculus deposition was very frequent (88.51%), no differences existing between men and women or between those interred in tumuli or in caves. Age at death was the only parameter independently related to calculus deposition by stepwise multivariate analysis. Periodontal disease was observed in 66.78% of the population, significantly more in men (χ2 = 4.88, P = 0.027). No differences existed between individuals buried in tumuli and in caves. Antemortem teeth loss was observed in 64.73% of individuals, no differences existing between men and women or between those interred in tumuli or in caves. There was a significant association between calculus and periodontal disease (χ2 = 18.07, P < 0.0001). Both caries (χ2 = 8.40, P = 0.004) and periodontal disease (χ2 = 44.96, P < 0.0001) were associated with tooth decay. However, the proportion of teeth with calculus deposition (in relation to observed teeth) was significantly higher among the population buried in tumuli (Z = 3.18, P = 0.001), although no differences were observed when the proportion of antemortem lost teeth and alveoli with periodontal disease were compared among people buried in tumuli and in caves, but women showed significantly lower proportions of alveoli with periodontal disease and antemortem tooth decay. These data suggest that the population buried in caves had a different dietary pattern to that of those buried in tumuli, since calculus deposition -more frequent in the latter-may be related to the consumption of proteins. The results also point to the existence of differences in diet between men and women.  相似文献   

3.
The main objective of this paper is to suggest an alternative approach for the investigation of domestication in the Levant. First, basic data regarding domestication in the Levant are presented. Then the various traditional approaches towards domestication in the prehistoric Levant, labeled (1) environmental, (2) social and anthropological, and (3) cognitive, are briefly reviewed. This discussion forms the basis for a proposal of a “holistic approach,” in which domestication is regarded as a long-term, multidimensional and multirelational phenomenon, including many elements—such as plants, animals, humans, material culture and ancestors—with increasing human manipulation of these various constituents. After a presentation of the theoretical framework, a growth metaphor is used to reconstruct the process of domestication (ca. 20,000–6500 B.P.) as a number of phases: (1) germination in the Kebaran; (2) development in the Early Natufian; (3) retreat/dormancy in the Late/Final Natufian; (4) growth in the Pre-Pottery Neolithic A; (5) florescence in the Early- and Middle Pre-Pottery Neolithic B: (6) further development in the Late Pre-Pottery Neolithic B; (7) dispersal in the Final Pre-Pottery Neolithic B and the Pottery Neolithic. In each of these phases, relations between the various elements are dealt with, special attention being paid to symbolical relations, as evidenced by “art” and ritual.  相似文献   

4.
In order to interpret strontium and oxygen isotope values in Neolithic human skeletons analysed previously, we begin to map the biologically available strontium, carbon and oxygen isotopic signatures of prehistoric southern Germany by analysing tooth enamel of pigs from archaeological sites distributed around the region. The mapping shows a marked upland–lowland difference in biologically available 87 Sr/ 86 Sr values, ranging between 0.7086 and 0.7103 in the sedimentary lowlands, and from 0.710 to as high as 0.722 in the crystalline uplands of the Odenwald, the Black Forest and the Bavarian Forest. In addition, carbon isotopes in the carbonate fraction of pig enamel were generally about 1–2 more enriched in 13 C in the uplands. Despite the expected depletion of 18 O with altitude, oxygen isotopes in pig enamel showed little correlation with site altitude, although for pig samples not older than the Iron Age there was some geographical correlation withδ18O patterns in modern precipitation.  相似文献   

5.
Chuaria is widespread in Late Precambrian deposits throughout the world. In China it has been found in the Jingeryu Formation of Jixian County, Tianjin, and in its equivalents in eastern China including the Nanfen Formation of Liaoning and Jilin Provinces, and the Liulaobei Formation of Anhui Province. In the latter, Chuaria is associated with the genus Tawuia which Hofmann (in Hofmann & Aitken, 1979) described as algae of undertermined affinity and which is based on material from Canada. The glauconitic sandstone directly resting upon Chuaria-bearing greyish-green shale of the Jingeryu Formation in Jixian County has a K-Ar age of 0.899 Ga. This paper describes C. circularis Walcott, T. dalensis Hofmann and T. sinensis n. sp., and discusses the morphology, biological and taxonomic affinities, and age and geographic distribution of Chuaria. Because of the association of Chuaria and Tawuia in the Mackenzie Mountains, Canada, and also in the area of Shouxian County, Anhui Province, China, it is considered that Chuaria and Tawuia probably have close affinities. According to their general morphology and occurrence, both may be marine planktonic multicellular algae.  相似文献   

6.
Archaeologists frequently underestimate the importance of children as well as craft skill acquisition in the formation of archaeological assemblages. Perhaps even more often they conflate the terms “novice” and “child” in ways that oversimplify the factors that are involved in incorporating new producers into craft production. In particular, the skill acquisition involved in stone tool production is influenced by a variety of factors, including danger, raw material value, raw material availability, and raw material recyclability, as well as a variety of social factors. This paper examines the influence of each of these factors and also suggests patterns useful in recognizing and distinguishing between novices and children in the archaeological record.
Jeffrey R. FergusonEmail:
  相似文献   

7.
The “coupes-à-socle” (footed cups) are ceramics which can be found in domestic Neolithic contexts in Brittany (Castellic, Auzay-Sandun), but more generally in non-domestic areas. Their ceremonial function has often been evoked, in particular as a perfume burner. The analysis by GC and GC/MS of two samples from the “Hougue Bie” (Jersey) passage graves showed the presence of vegetable fatty acids, degraded n-alkanes and terpenoïds, biomarkers of birch bark tar. The presence of such substances could be explained either by the use of the “coupes-à-socle” for burning birch bark tar as an odoriferous product or their use as an everyday vessel for heating and increasing tar plasticity. However, the limited occurrence of this type of ceramic in habitat sites supports the former utilisation. This first report of the presence of birch bark tar in “coupes-à-socle” thus suggests use of this tar as an odoriferous product, in addition to its numerous, previously recognised, more technical uses.  相似文献   

8.
Early to Middle Tournaisian conodont faunas with Siphonodella from ten sections in eastern Australia, between Gloucester in New South Wales and Rockhampton in Queensland, may be referred to the following ‘standard’ zones; 1 sulcata, 2 upper duplicata, 3 sandbergi, 4 lower crenulata and 5 isosticha-upper crenulata, in ascending order. In eastern Australia the first occurrences of Gnathodus cuneiformis, G. delicatus, G. typicus and Protognathodus cordiformis, near the base of the lower crenulata zone, are significantly earlier than in Europe and North America. Consequently the base of the isosticha-upper crenulata zone in eastern Australia is defined by the first appearance of G. punctatus rather than that of G. delicatus. On the present evidence it is difficult to reconcile some brachiopod and conodont occurrences in the Early-Middle Tournaisian of eastern Australia.

Seventeen discrete conodont species are discussed, four of which are described informally: Dinodus sp. nov. A, Dinodus sp. nov. B, Pinacognathus sp. nov. A, and a species of Siphonodella transitional between S. cooperi and S. crenulata.  相似文献   

9.
This study presents the results of an isotopic analysis of nine naturally mummified individuals—three adults, two adolescents, one juvenile, and three infants—recovered from the Hets Mountain Cave site in southern Mongolia, where they had been secondarily deposited. All of the individuals show evidence of violent perimortem trauma, but no skeletal indicators of nutritional or disease-related stress. Multi-isotopic data (δ13C, δ15N, δ18O, 87Sr/86Sr, and 20nPb/204Pb) were characterized in multiple tissues from each individual when possible, in order to reconstruct diet composition and residential origin at different points in life. Specifically, δ13C and δ15N in bone carbonate and collagen (N = 8) and hair keratin (N = 4) were coupled with enamel carbonate δ18O and δ13C (N = 3) and enamel 87Sr/86Sr, and 20nPb/204Pb (N = 3) to assess diet and residential mobility in relation to skeletal indicators of health and trauma. Results are consistent with a persistence of mixed C3/C4 pastoral subsistence and general stability of diet composition over the life course, in contrast to contemporary accounts of widespread famine and a dependence on grains imported from China throughout the region. However, results also suggest that at least some individuals may have migrated to this region of southern Mongolia from elsewhere during life, meaning that their dietary isotopic profiles may not represent local subsistence patterns near the Hets Mountain Cave site. Overall, these results speak to the utility of life course oriented multi-isotopic analysis in complementing more top-down historical analyses in understanding variation in subsistence, nutrition, and migration in regions undergoing significant political and economic turmoil.  相似文献   

10.
A review of archaeobotanical data, together with new, still unpublished data, from Roman sites in conventus Bracaraugustanus suggests the Romanization of the northwest Iberia brought little changes to the agricultural strategies of local communities in indigenous-type settlements. The main crops remain the same as in the Iron Age: Triticum aestivum/durum, Panicum miliaceum, Hordeum vulgare subsp. vulgare, Triticum turgidum subsp. dicoccum and T. aestivum subsp. spelta, Avena and Vicia faba. The first secure reference for the cultivation of Secale cereale in the region comes from a Roman context, suggesting that it was introduced in this period, although it probably remained a minor crop.  相似文献   

11.
ABSTRACT

This essay surveys responses to Macpherson’s Ossian in Irish literature, alongside analysis of the development of literary Celticism. Despite being a key text behind the development of Celticism in Irish writing, Ossian is consciously rejected in Irish Romanticism and in the Celtic Revival. However, Ossian becomes a symbol of literary recycling and mental fragmentation in Irish Modernism. Texts studied in this essay include Owenson’s The Wild Irish Girl, Joyce’s Finnegans Wake, and Beckett’s Murphy.  相似文献   

12.
Three new species of the Araucariaceae are described from leaf remains, Araucaria readiae from the Early Eocene Regatta Point flora, A. hastiensis from the Middle-Late Eocene Hasties flora, and Agathis tasmanica from the Early Oligocene-Early Miocene Little Rapid River flora. Additionally, emended diagnoses are presented for Araucarioides linearis and A. annulata. A. readiae is the first organically preserved species in the section Eutacta described from Tasmania, A. hastiensis is the first record of a species not in section Eutacta in Tasmania, and A. tasmanica is the first record of Agathis in Tasmania. These species, along with other records from south-eastern Australia indicate the presence of a high diversity of araucarian species in the region in the Early-Middle Tertiary, although no species survive there today. Climatic change and competition from angiosperms may have led to their demise in that region.  相似文献   

13.
Resulted from different causes, the majority of traditional cities in modern China underwent a decline in various degrees. The causes of the decline of Suzhou, Hangzhou, and Yangzhou which have started to develop their new industry and commerce since mid-Qing Dynasty lies in such aspects as: the lose of transportation superiority in modern China; the fatal destruction caused by Taiping Revolution; the affects of the rising of Shanghai; the recession of traditional economy and slowed development of new economy; and the conservatism in thinking and ideas etc. Translated by Huang Bangfu from Xinan Minzu Daxue Xuebao 西南民族大学学报 (Journal of Southwest University for Nationalities), 2007, (4): 1–11  相似文献   

14.
ABSTRACT

Mary Darby Robinson is well known for writing her final volume of poems, the Lyrical Tales (1800), as a direct answer, sometimes poem by poem, to Wordsworth and Coleridge’s 1798 Lyrical Ballads. What has been less studied is how deliberately hybrid in style and allusions her response-poems are in the Tales, especially how prominently they foreground Gothic imagery, theatricality, and hyperbole in poems that also ape the emerging “romantic” mode of the Ballads themselves. Part of that “cheekiness,” I argue, stems from the condemnation of the Gothic that both Wordsworth and especially Coleridge had articulated in print, while also echoing it, albeit in highly modified ways, in their poetry. Most of what Robinson attempts with her hybrid Tales, though, develops the penchant in Gothic for symbolizing deep and unresolved ideological conflicts in Western culture. Her answers to Wordsworth and Coleridge, which I exemplify with selected Robinson Tales, therefore, bring out those very conflicts underlying, haunting, and even tormenting the speakers and the subject-matter in the original Lyrical Ballads.  相似文献   

15.
Abstract

The results of an analysis on plant remains (fruit, seeds, pollen and wood) found in sediments in a Roman well in Vada Sabatia (Vado Ligure, Liguria, Italy), dated between the first and fourth centuries AD are presented. The remains are well preserved and constitute an exceptional record of the Ligurian area. Five layers have been recognised: three corresponding to the well when in use and two to the well when it was no longer in use. The vegetational cover of the area has been found to be similar to that observed in the coastal plain near Albingaunum (Albenga) pertaining to the same period. Moreover, the two superficial layers have cumulated a large amount of macroremains related to the period in which the well was no longer in use. The principal tree and vegetable crops and cereals of the coastal plain were present, due to the influence of maritime and mercantile trade, as were the prevailing ruderal and weed species and the tree cover. The presence of carpological remains of Castanea sativa, Secale cereale, Beta vulgaris and Cucumis sativus is reported for the first time in the Roman Age in Liguria. The influence of the arrival of the Romans can be seen from new crops, such as Prunus persica, and the introduction of exotic fruit like Phoenix dactylifera and Ziziphus jujuba. Several wooden artefacts, for example, a rack for drying lucerne and a tool handle, made of Cornus or Viburnum and Viburnum cf. lantana respectively, have been found. The well has proved to be an ideal location for the preservation of plant remains compared with other studied archaeological situations in Liguria and in Southern France, as it presents a higher variety of cultivated fruits, vegetables and cereals.  相似文献   

16.
Stable isotope analysis of charred archaeobotanical cereal grains has the potential to provide direct evidence of crop growing conditions in the past and to refine palaeodietary predictions. If isotope values of archaeobotanical material are to be considered robust, it is necessary to characterise the compositional changes associated with their charring and burial. This study used a suite of analytical techniques, including FT-IR and solid state 13C NMR, to characterise changes in the biochemical composition of modern einkorn grains with heating at 230 °C for 2 h, 4 h, 8 h and 24 h, encompassing conditions that replicate their undistorted ancient counterparts. The biochemical composition of archaeobotanical charred einkorn grains was also investigated by FT-IR and solid state 13C NMR in order to assess the changes in composition which occur during burial. Results of FT-IR and solid-state 13C NMR show that heating of modern einkorn grains resulted in Maillard reactions between cereal proteins and starch, forming high molecular weight melanoidins, which contain both alkyl and aromatic carbon. Loss of low molecular weight carbon and nitrogen-containing volatiles resulted in a slight but non-systematic increase in the δ13C values and a systematic increase of 0.8‰ in the δ15N values of the charred einkorn grains. Solid-state 13C NMR shows that the ancient charred einkorn grains consisted entirely of aromatic carbon and retained a similar proportion of nitrogen to their modern 24 h charred counterparts, despite a significantly lower concentration of amino acids. This indicates that the amino acid nitrogen in the ancient charred grains was retained in the stable melanoidins whose polymeric structure makes them resistant to subsequent degradation.  相似文献   

17.
This article focuses on two disparate figures in the French colonial period in Africa, the ex-poet Arthur Rimbaud and the ex-soldier Charles de Foucauld. Between 1883 and 1884, each lived in Africa in self-imposed exile of a sort, and undertook rigorous exploration of the region to which he had relocated himself. Both composed reports on their regions of the ‘dark continent,’ and both reports were submitted to, and recognized by, the Société de Géographie back in Paris. The two geographical texts – Rimbaud's Rapport sur l'Ogadine and de Foucauld's Reconnaissance au Maroc – are watersheds of life-writing, as much as they are representations of colonial Africa observed by Frenchmen. Through comparing the two desert narratives, and considering the two authors' African lives, I argue that the process of writing about the desert actually evokes the essential character of each writer's voice, a voice to which he only found access in the desert. Finally, these voices in turn provide valuable information about the relationship between France and Africa, colonial force and colony, and about the various forms of resistance to each of those roles.  相似文献   

18.
G. Etiope  A. Ionescu 《Geofluids》2015,15(3):438-452
Metal‐catalysed CO2 hydrogenation is considered a source of methane in serpentinized (hydrated) igneous rocks and a fundamental abiotic process germane to the origin of life. Iron, nickel, chromium and cobalt are the catalysts typically employed in hydrothermal simulation experiments to obtain methane at temperatures >200°C. However, land‐based present‐day serpentinization and abiotic gas apparently develop below 100°C, down to approximately 40–50°C. Here, we document considerable methane production in thirteen CO2 hydrogenation experiments performed in a closed dry system, from 20 to 90°C and atmospheric pressure, over 0.9–122 days, using concentrations of non‐pretreated ruthenium equivalent to those occurring in chromitites in ophiolites or igneous complexes (from 0.4 to 76 mg of Ru, equivalent to the amount occurring approximately in 0.4–760 kg of chromitite). Methane production increased with time and temperature, reaching approximately 87 mg CH4 per gram of Ru after 30 days (2.9 mgCH4/gru/day) at 90°C. At room temperature, CH4 production rate was approximately three orders of magnitude lower (0.003 mgCH4/gru/day). We report the first stable carbon and hydrogen isotope ratios of abiotic CH4 generated below 100°C. Using initial δ13CCO2 of ‐40‰, we obtained room temperature δ13CCH4 values as 13C depleted as ?142‰. With time and temperature, the C‐isotope separation between CO2 and CH4 decreased significantly and the final δ13CCH4 values approached that of initial δ13CCO2. The presence of minor amounts of C2‐C6 hydrocarbons is consistent with observations in natural settings. Comparative experiments at the same temperatures with iron and nichel catalysts did not generate CH4. Ru‐enriched chromitites could potentially generate methane at low temperatures on Earth and on other planets.  相似文献   

19.
The state of a group of glaciers in the northern Mackenzie Mountains across the Yukon‐Northwest Territories border was investigated over a period of three decades, using Landsat TM and OLI imagery from 1987, 1994, 1999, 2004, 2013, and 2017 to examine changes in glacier extents. A thresholded red/shortwave infrared band ratio image was used to delineate glacier boundaries. The total area of 74 glaciers in the study area decreased from 52.78 ± 1.32 km2 in 1987 to 24.89 ± 0.62 km2 in 2017, a loss of 27.89 ± 1.39 km2 or 52.8 ± 2.6%, with a mean rate of reduction of 1.8% · a?1. Smaller glaciers experienced larger relative changes in area. In this study, the rates of reduction are high compared to decreases reported for other glaciers in the region in the late 20th century. Based on linear extrapolation of the trend in values of total glacier area, it is predicted—subject to uncertainties in how glaciers diminish in size and eventually disappear—that the study area could be free of visible glacier cover within three decades.  相似文献   

20.
Monazite (CePO4) and xenotime (YPO4) are important accessory minerals in metasediments. They host significant rare earth elements (REE) and are useful for geochronology and geothermometry, so it is essential to understand their behavior during the metasomatic processes that attend high‐grade metamorphism. It has been proposed that F‐bearing fluids enhance solubility and mobility of REE and Y during high‐grade metamorphism. We assessed this possibility by determining the solubility of synthetic CePO4 and YPO4 crystals in H2O–NaF fluids at 800°C and 1 GPa. Experiments used hydrothermal piston‐cylinder and weight‐loss methods. Compared to the low solubilities of CePO4 and YPO4 in pure H2O (0.04 ± 0.04 and 0.25 ± 0.04 millimolal, respectively), our results indicate an enormous increase in the solubility of both phosphates with increasing NaF concentration in H2O: CePO4 solubility reaches 0.97 molal in 20 mol.% NaF, and YPO4 shows an even stronger solubility enhancement to 0.45 molal in only 10 mol.% NaF. The greatest relative solubility increases occur at the lowest NaF concentration. The solubilities of CePO4 and YPO4 show similar quadratic dependence on NaF, consistent with possible dissolution reactions of: CePO4 + 2NaF =  CeF2+ + Na2PO4? and YPO4 + 2NaF = YF2+ + Na2PO4?. Solubilities of both REE phosphates are significantly greater in NaF than in NaCl at equivalent salt concentration. A fluid with 10 mol.% NaCl and multiply saturated with fluorite, CePO4, and YPO4 would contain 1.7 millimolal Ce and 3.3 millimolal Y, values that are respectively 2.1–2.4 times greater than in NaCl‐H2O alone. The results indicate that Y, and by extension heavy rare earth elements (HREE), can be fractionated from LREE in fluorine‐bearing saline brines which may accompany granulite‐facies metamorphism. The new data support previous indications that REE/Y mobility at these conditions is enhanced by complexing with F in the aqueous phase.  相似文献   

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