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1.
古铜矿遗址围岩表层有害生物的防治   总被引:3,自引:0,他引:3  
铜绿山古铜矿遗址地处长江中游地区、空气湿度大、围岩表层有害生物成片生长蔓延,对遗址的长期保护造成极大威胁。对此采取了改变遗址的环境条件、喷涂消杀药品的方法,消除了围岩表层有害生物的危害。经过一年半的观察表明该方法是可行的。  相似文献   
2.
Prehistoric images are particularly versatile and difficult to grasp. In a few cases of historical continuity, local cultural glosses provide researchers with a rich corpus of data and help in the interpretation of the imagery. Such approaches contribute to the interpretation of the material in a frozen time perspective. Their impact on the development of archaeological methodologies enabling researchers to deal with strictly prehistoric image making traditions without any known descendant communities remains to be felt. This paper is an attempt to develop a subtle and robust archaeological methodology for the study of prehistoric images. The suggested approaches are replicable, and conclusions are falsifiable.Les images préhistoriques sont particulièrement versatiles, et leur sens difficile à cerner en raison de leur polysémie. Dans une poignée de cas, là ou il y a continuité historique, les chercheurs ont reussi à constituer une riche documentation sur les pratiques culturelles liées à l'utilisation des images. Ils/elles parviennent ainsi à des niveaux d'interpretation très detaillée, dans une conception paradoxalement réifiée des sociétés en question, conservant des pratiques culturelles inchangées pendant des millénaires. L'impact de telles approches sur l'élaboration de bonnes méthodes archéologique est négligeable. Dans la plupart des cas, les images et les vestiges matériels sont le uniques témoins des sociétés préhistoriques étudiées. Cet article s'efforce de developper des méthodes, à la fois subtiles et robustes, permettant une analyse systématique des images préhistoriques. Les méthodes proposées sont réplicables, et les conclusions refutables.  相似文献   
3.
This paper examines the rock art of the nyau secret society of eastern Zambia and central Malai. The art dates principally from the nineteenth and early twentieth centuries. It has been known to researchers since the 1970s but has given up few of its secrets. I examine the questions of why the art was made and why the tradition ceased. Key to answering these is the realization that the art belonged to a specific historical and geographic context: the era and area where nyau was forced to become an underground movement because of its suppression by Ngoni invaders, missions, and the later colonial government. The art provides us with detailed insights into the way nyau has served in the process of overcoming and manipulating the traumatic social changes faced by Chea society in the last few centuries.Cet article examine l'art rupestre de la société secrète de nyau au est du Zambia et Malai centrale. L'art date principalement aux dix-neuvième et bas vingtième siècles. Recherchers ont su l'art depuis les années soixante-dix, mais ils ont appris peu de ses secrets. J'examine les questions de pourquoi l'art était fabriquer et pourquoi la tradition a cessé. Pour résoudre ces questions c'est important à réaliser que l'art était à sa place dans un milieu spécifique d'histoire et géographie: au temps et place où nyau était forcer à devenir un mouvement clandestin à cause de sa répression par les envahisseurs Ngoni, les missions et, plus tard, le gouvernement colonial. L'art nous donne les aperçus détaillé sur comment nyau a servi dans le procès à surmonter et manipuler les changements traumatiques que la société Chea a bravé dans les siècles récents.  相似文献   
4.
Mauermanshoek Shelter, in the Korannaberg of the eastern Free State, has traditional San hunter–gatherer rock art together with white finger-painted horsemen of uncertain authorship. The excavated material dates to between 3500 bp and approximately 200 bp. The lithic assemblages show little change throughout, but ceramics, glass beads, and domesticated animal remains appear in the uppermost levels. The issue of most interest is that of the shelter's occupancy in the last few hundred years. Historical records show that the ethnic composition of the eastern Free State was complex during this time and that there were both aggressive and cooperative interactions between the various groups. Kora pastoralists were notorious stock raiders and the secure identification of other people on the landscape was complicated by a tendency for early writers to call all raiders Kora. A combination of archaeological and historical evidence suggests that San occupied the shelter for most of its history but that Kora herders may have been responsible for the finger-painted horsemen somewhere between 1837 and 1851 when a Wesleyan Mission Station, Merumetsu, served the Kora of Korannaberg.La grotte de Mauermanshoek, située dans le Korannaberg, à l'est de la province du Free State, contient des peintres rupestres de tradition San, réalisées par des chasseurs/bergers, ainsi que des cavaliers blancs, peint avec le doigt, d'une origine incertaine. Le matériel qu'on a trouvé dans les fouilles daté d'une période entre 3500 bp et approximativement 200 bp. L'industrie lithique est très homogène sur l'ensemble du site, mais des céramiques, des perles de verre et des restes d'animaux domestiques sont présents aux niveaux supérieurs. L'occupation de l'abri pendant les quelques centaines d'années passées est d'un inérêt tout particulier. Selon les archives historiques, la composition ethnique de la partie est du Free State était, à l'époque, complexe et il y avait les interactions à la fois agressifs et coopératifs entre les groupes différents. Les pasteurs Kora sont bien connus pour leur réputation d'attaquer les troupeaux mais l'identification certaine des autres peuplades est compliquée par le fait que les premiers écrivains rapportaient tous les aggresseurs comme des Kora. Une combinaison d'indices archeologiques et historiques suggère que les San occupèrent cette grotte pour la plus grande partie de son histoire mais que des bergers Kora pourraient être à l'origine des cavaliers peints avec le doigt, probablement entre 1837–1851, la période durant laquelle une mission Wesleyan servait le Kora de la région du Korannaberg.  相似文献   
5.
6.
The Krafla geothermal system is located in Iceland's northeastern neovolcanic zone, within the Krafla central volcanic complex. Geothermal fluids are superheated steam closest to the magma heat source, two‐phase at higher depths, and sub‐boiling at the shallowest depths. Hydrogen isotope ratios of geothermal fluids range from ?87‰, equivalent to local meteoric water, to ?94‰. These fluids are enriched in 18O relative to the global meteoric line by +0.5–3.2‰. Calculated vapor fractions of the fluids are 0.0–0.5 wt% (~0–16% by volume) in the northwestern portion of the geothermal system and increase towards the southeast, up to 5.4 wt% (~57% by volume). Hydrothermal epidote sampled from 900 to 2500 m depth has δD values from ?127 to ?108‰, and δ18O from ?13.0 to ?9.6‰. Fluids in equilibrium with epidote have isotope compositions similar to those calculated for the vapor phase of two‐phase aquifer fluids. We interpret the large range in δDEPIDOTE and δ18OEPIDOTE across the system and within individual wells (up to 7‰ and 3.3‰, respectively) to result from variable mixing of shallow sub‐boiling groundwater with condensates of vapor rising from a deeper two‐phase reservoir. The data suggest that meteoric waters derived from a single source in the northwest are separated into the shallow sub‐boiling reservoir, and deeper two‐phase reservoir. Interaction between these reservoirs occurs by channelized vertical flow of vapor along fractures, and input of magmatic volatiles further alters fluid chemistry in some wells. Isotopic compositions of hydrothermal epidote reflect local equilibrium with fluids formed by mixtures of shallow water, deep vapor condensates, and magmatic volatiles, whose ionic strength is subsequently derived from dissolution of basalt host rock. This study illustrates the benefits of combining phase segregation effects in two‐phase systems during analysis of wellhead fluid data with stable isotope values of hydrous alteration minerals when evaluating the complex hydrogeology of volcano‐hosted geothermal systems.  相似文献   
7.
Ritual landscapes at sea are marked in the cognitive world of coastal people by a primary antagonism between sea and land. This contrast is negotiated by liminal 'foreign' agents, selected for their symbolic adherence to either part. The primary source of maritime culture is fishing as a survival of past hunter-gatherer societies. Forms of religious or magical management of this contrast are manifold, from recent superstitious magic to powerful symbols in ancient worship, objects, art, architecture and cult. Also described are ways of using the sea on land as a magic metaphor and a fundamental point of reference. Related dichotomies and ways of negotiating them, such as the liminal agent, exist elsewhere in the cognitive world of pre-industrial societies, so these ideas could have applications in archaeology.
© 2005 The Nautical Archaeology Society  相似文献   
8.
探索和研究表明,岩画断代问题仍然是困扰岩画研究的难题之一,其主要原因是岩画本身不能够提供可供断代的直接依据。本文综述了目前岩画断代研究中经常使用的自然科学和考古学方法及其存在的问题,提出应用AMS14C是今后研究我国岩绘画断代问题的首选方法,解决岩刻画的断代问题则主要有赖于微腐蚀方法。  相似文献   
9.
岩画意义的解释经常会出现望图生义或者恣意猜度的现象,导致学术界对岩画的解释产生了偏见。为了避免这种情况,在解读岩画的时候应当充分考虑各种可能的因素,如岩画所处的环境,岩画自身之间的关联,岩画产生地所呈现出来的地方性知识,其他学科的支持等。  相似文献   
10.
D. BROSETA  N. TONNET  V. SHAH 《Geofluids》2012,12(4):280-294
The various modes of acid gas storage in aquifers, namely structural, residual, and local capillary trapping, are effective only if the rock remains water‐wet. This paper reports an evaluation, by means of the captive‐bubble method, of the water‐wet character in presence of dense acid gases (CO2, H2S) of typical rock‐forming minerals such as mica, quartz, calcite, and of a carbonate‐rich rock sampled from the caprock of a CO2 storage reservoir in the South‐West of France. The method, which is improved from that previously implemented with similar systems by Chiquet et al. (Geofluids 2007; 7 : 112), allows the advancing and receding contact angles, as well as the adhesion behavior of the acid gas on the mineral substrate, to be evaluated over a large range of temperatures (up to 140°C), pressures (up to 150 bar), and brine salinities (up to NaCl saturation) representative of various geological storage conditions. The water‐receding (or gas‐advancing) angle that controls structural and local capillary trapping is observed to be not significantly altered in the presence of dense CO2 or H2S. In contrast, some alteration of the water‐advancing (or gas‐receding) angle involved in residual trapping is observed, along with acid gas adhesion, particularly on mica. A spectacular wettability reversal is even observed with mica and liquid H2S. These results complement other recent observations on similar systems and present analogies with the wetting behavior of crude oil/brine/mineral systems, which has been thoroughly studied over the past decades. An insight is given into the interfacial forces that govern wettability in acid gas‐bearing aquifers, and the consequences for acid gas geological storage are discussed along with open questions for future work.  相似文献   
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