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961.
Kenneth J. McNamara John P. Rexilius Neil G. Marshall Robert A. Henderson 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):163-168
The first known ammonite from the Maastrichtian of the Perth Basin, a single, incomplete specimen of Grossouvrites gemmatus (Huppé, 1854), is described from core material from the Lancelin No. 1 borehole. Foraminiferal and nannoplankton evidence date the ammonite as middle Maastrichtian; its age is also assessed on the basis of dinoflagellate assemblages from this section, but these give a less precise dating. The position of the ammonite with respect to a mid-Maastrichtian disconformity, which probably extended along much of the Western Australian margin is discussed. 相似文献
962.
K. Gilliland I.A. Simpson W.P. Adderley C.I. Burbidge A.J. Cresswell D.C.W. Sanderson R.A.E. Coningham M. Manuel K. Strickland P. Gunawardhana G. Adikari 《Journal of archaeological science》2013,40(2):1012-1028
We identify and offer new explanations of change in water management infrastructure in the semi-arid urban hinterland of Anuradhapura, Sri Lanka between ca. 400 BC and AD 1800. Field stratigraphies and micromorphological analyses demonstrate that a complex water storage infrastructure was superimposed over time on intermittently occupied and cultivated naturally wetter areas, with some attempts in drier locations. Our chronological framework, based on optically stimulated luminescence (OSL) measurement, indicates that this infrastructure commenced sometime between 400 and 200 BC, continued after Anuradhapura reached its maximum extent, and largely went into disuse between AD 1100 and 1200. While the water management infrastructure was eventually abandoned, it was succeeded by small-scale subsistence cultivation as the primary activity on the landscape. Our findings have broader resonance with current debates on the timing of introduced ‘cultural packages’ together with their social and environmental impacts, production and symbolism in construction activities, persistent stresses and high magnitude disturbances in ‘collapse’, and the notion of post ‘collapse’ landscapes associated with the management of uncertain but essential resources in semi-arid environments. 相似文献
963.
964.
Roberto J. González 《Anthropology today》2012,28(2):21-25
This article reflects upon the methodological challenges posed by the study of secretive organizations and programmes. In particular, it examines the question: when participant‐observation is not a feasible option, what techniques can anthropologists use to shed light upon covert military and intelligence agencies and the corporations that they contract? After reviewing anthropological research on secret societies from the late 18th and early 19th century, the author turns to contemporary anthropological work on bureaucratic institutions and initiatives that operate in secret. The author's own research into the US Army's Human Terrain System serves as an illustration. By adapting Laura Nader's suggestions for ‘studying up, down, and sideways’, the article suggests that documentary analysis (of both openly accessible and classified documents), interviews, and ‘self‐analysis’ provide a fruitful combination of methods for an anthropology of the covert. 相似文献
965.
966.
This paper examines 20th-century environmental change in the subhumid southwestern Canadian Plains, specifically in relation to the dominant agricultural landscape and to the climate of the past millennium as reconstructed from proxy data. Anthropogenic landscape change in the last century has been dominated by the conversion of grasslands to ranchland and cropland. This has heightened landscape vulnerability to climatic fluctuations, especially drought. Instrumental climate records, extending back to the 1880s, highlight the variability of precipitation in this region. Proxy environmental records, derived from lake cores and tree-ring analysis, extend this picture into the last millennium and show that drought has been a recurring theme of the Prairie climate. Tree-ring records suggest that some droughts in the last millennium may have exceeded in severity any in the instrumental record. The sustainability of Prairie agriculture depends on adaptation to the amplitudes of climatic change and variability evident in these proxy records. Dans cet article nous examinons les changements environnementaux qui sont survenus pendant le 20ème siècle dans les plaines canadiennes sèches du sud-ouest, spécifiquement par rapport au paysage agricole dominant et au climat du dernier millénaire qui a été déterminéà partir de données de procuration. La transformation des prairies en ranchland et cropland est le changement du paysage le plus important dont l'homme est responsable, pour le dernier siècle. À cause de ce changement, le paysage est plus vulnérable aux fluctuations climatiques - à la sécheresse en particulier. Les enregistrements instrumentaux de climat, qui reculent jusqu'aux années 1880, mettent en évidence la variabilité des précipitations dans cette région. Les enregistrements environnementaux de procuration, dérivés d'échantillons pris dans les lacs et de la dendroanalyse, étendent cette image dans le dernier millénaire et prouvent que le thème de la sécheresse est apparu souvent dans les analyses du climat du prairie. Les enregistrements de boucles d'arbre suggèrent que, dans le dernier millénaire il y avait des sécheresses qui étaient peut-être si sévères que les instruments n'ont pas pu les enregistrer. Si l'agriculture veut survivre comme entreprise dans les prairies, il faudra qu'elle s'adapte aux amplitudes de changement et de variabilité du climat qui ont été constatées dans les données de procuration. 相似文献
967.
An Egyptian metal vase from the Ptolemaic period was investigated metallurgically and fractographically. The metal is nearly pure silver. Despite its high purity (in archaeological terms) it is severely embrittled and cracked, mainly along grain boundaries. Factors contributing to this damage are work-hardening and residual microstructural deformation (slip and twinning), corrosion along slip lines and twin boundaries, corrosion in bauds that are the remains of coring, large equiaxed grains, externally applied forces and internal residual stresses. The metal is now friable. This must be taken into account during any further restoration of the vase: a procedure is suggested. 相似文献
968.
969.
The energy dispersive X-ray fluorescence technique was employed to study non-destructively the surface of 66 samples of Chinese porcelain, of different periods and origins, and determine the contents of 13 chemical elements, namely, Ti, Mn, Fe, Co, Ni, Cu, Zn, Ga, Pb, Rb, Sr, Y and Zr. Principal components analysis was performed on these 13 variables, and scatter plots, incorporating the first, second and third principal components, used to study the clustering behaviour of the data. Based on these results, discriminant analysis was then performed on the data, and discriminant functions established for attributing the period and origin of the porcelains. 相似文献
970.
To date, there has not been a sustained attempt to bring the philosophy of the Third Way into foreign policy. In order to fill this gap, the authors turn to the idea of 'good international citizenship' pioneered by the former Australian Foreign Minister, Gareth Evans. It is argued that good international citizenship provides a conceptual rationale for an ethical foreign policy as well as a standard for judging the priority accorded to the goals of security, trade and human rights. Through an examination of a number of cases, the authors conclude that Britain's record as a good international citizen has been uneven and argue—against Labour's critics—that the government has set a new course for Britain's way in the world. More importantly, it has encouraged a public debate about the meaning and priority accorded to the promotion of different values. 相似文献