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111.
ESR geochronology of the Minjiang River terraces at Wenchuan, eastern margin of Tibetan Plateau, China 总被引:1,自引:0,他引:1
Chun-Ru Liu Gong-Ming Yin Hui-Ping Zhang Wen-Jun Zheng Pierre Voinchet Fei Han Duo Wang Wei-Juan Song Jean-Jacques Bahain 《Geochronometria》2013,40(4):360-367
The Minjiang River terrace along the Longmen Shan fault zone near Wenchuan, at the eastern margin of the Tibetan Plateau, China, provides archives for tectonic activity and quaternary climate change. However, previous studies were not able to provide ages older than 100 ka due to the limitations of dating material or/and methods applied to date the fluvial sediments. In this study, we used the ESR signal of the Ti-Li center in quartz to obtain the ages of four higher terraces (T3–T6). According to the results, the terraces T3 to T6 were formed at 64±19 ka, 101±15 ka, 153±33 ka, and 423±115 ka, respectively. Combined with previous studies, these results indicate that the formations of all terraces correspond to glacial/interglacial transition periods, such as, T1-T5 being correlated to MIS2/1, MIS4/3, MIS5d/5c, and MIS6/5e respectively, while T6 probably to MIS12/11. According to these data, it is found that the average incision rate was significantly higher over the last 150 ka than that previous 100 ka (250 to 150 ka). As both tectonics and climate have affected the formation of these terraces, in addition to the overall uplifting of Tibetan Plateau, the regional uplift due to isostasy would be an additional tectonic factor in the formation of river terraces in the eastern margin of Tibetan plateau. 相似文献
112.
Australia is currently negotiating a framework treaty with the European Union (EU) that aims at closer cooperation on a wide range of shared policy goals. The treaty is not expected to include trade-liberalisation commitments. This article queries why this is, given the importance of trade and business relations with the EU for Australia, and the fact that the EU exerts international influence primarily as a trade power, rather than a foreign and security policy power. Since 2006, the EU has also been negotiating ‘new-generation’ bilateral free trade agreements (FTAs), focusing on tariffs and regulatory non-tariff trade barriers. It has now committed itself to FTA negotiations with many of Australia's trade partners in Asia and the Organisation for Economic Co-operation and Development. An FTA and a complementary framework treaty were concluded with South Korea in 2010, and the EU is currently negotiating a similar package with Canada. As Australia and Canada are comparable trade partners for the EU, the article argues that an FTA on the EU–Canada model could be a more effective avenue for Australia to achieve deeper engagement with the EU. 相似文献
113.
Cécile Tannier Isabelle Thomas Gilles Vuidel Pierre Frankhauser 《Geographical analysis》2011,43(2):211-227
Fractal geometry can be used for determining the morphological boundaries of metropolitan areas. A two‐step method is proposed here: (1) Minkowski's dilation is applied to detect any multiscale spatial discontinuity and (2) a distance threshold is located on the dilation curve corresponding to a major change in its behavior. We therefore measure the maximum curvature of the dilation curve. The method is tested on theoretical urban patterns and on several European cities to identify their morphological boundaries and to track boundary changes over space and time. Results obtained show that cities characterized by comparable global densities may exhibit different distance thresholds. The less the distances separating buildings differ between an urban agglomeration and its surrounding built landscape, the greater the distance threshold. The fewer the buildings that are connected across scales, the greater the distance threshold. 相似文献
114.
There has been relatively little comparative research undertaken on sub‐national cultural policy. This article aims to contribute to the development of sub‐national comparative studies by assessing the utility of national cultural policy approaches for comparative research at the sub‐national level in Canada. Drawing on studies of national cultural policy, the authors develop three main approaches to cultural policy and administration – the French, British and hybrid approaches – and explore their applicability to the origin and evolution of cultural policy and administration in the Canadian provinces of Québec and Ontario. This exploratory research suggests there is room for optimism in drawing on national‐level experiences to undertake sub‐national comparative cultural policy research, particularly for comparisons over broad time periods. The study also suggests that it will be important in subsequent research to further elaborate the models for present‐day comparative analysis and to refine and adapt them to reflect specificities at the provincial level of analysis. 相似文献
115.
116.
José-Miguel Tejero Marianne Christensen Pierre Bodu 《Journal of archaeological science》2012,39(2):332-346
In technological approaches to prehistoric industries, there is currently a renewed interest in the transformation of osseous materials. This approach requires the construction of a technical reference base of manufacturing stigmata, as well as of the procedures and methods used to produce tool blanks.One of the better known processes for the production of blanks in the Upper Palaeolithic is extraction by a double longitudinal groove, observed only in the Gravettian. Aurignacian artefacts indicate that during this period blanks were obtained through a procedure of longitudinal fracturing (splitting) or diffuse percussion fracturing. The manner of implementing these procedures is, however, still poorly known.In order to better characterise this stage in the manufacturing of blanks for antler points, we conducted an experimental study. Based on a thorough analysis of the Spanish archaeological materials, we tested the procedure of fracturing by indirect percussion on deer antler. The results provide new criteria for the identification of blanks and their manufacturing processes. They also emphasize the possibility of predetermining the size of the blank and, consequently, the size of future projectile point. 相似文献
117.
118.
This article surveys the legislation concerning the residence of colonial slaves and nonwhites in general in eighteenth-century France. On the one hand, it shows an increasing concern with race on the part of the elite, heavily influenced by colonial attitudes, leading to laws increasingly reminiscent of apartheid; on the other hand, it reveals the state's inability to enforce its own regulations in the context of privilege, resulting in a legal confusion typical of late ancien-ŕegime law. 相似文献
119.
Geostatistical methods have rarely been applied to area-level offense data. This article demonstrates their potential for improving the interpretation and understanding of crime patterns using previously analyzed data about car-related thefts for Estonia, Latvia, and Lithuania in 2000. The variogram is used to inform about the scales of variation in offense, social, and economic data. Area-to-area and area-to-point Poisson kriging are used to filter the noise caused by the small number problem. The latter is also used to produce continuous maps of the estimated crime risk (expected number of crimes per 10,000 habitants), thereby reducing the visual bias of large spatial units. In seeking to detect the most likely crime clusters, the uncertainty attached to crime risk estimates is handled through a local cluster analysis using stochastic simulation. Factorial kriging analysis is used to estimate the local- and regional-scale spatial components of the crime risk and explanatory variables. Then regression modeling is used to determine which factors are associated with the risk of car-related theft at different scales. 相似文献
120.