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81.
Globalisation is manifested in the Mekong Region both through processes and discourses that reflect the ideology of a borderless world allowing easy passage of capital and commodities, and through resistance to such processes in an increasingly transnationalised civil society movement. However, more immediately significant supranational integrative agendas take the form of regionalisation, a process that has received less attention but which raises analogous concerns of re-scaled governance. The Asian Development Bank (ADB) has been a catalysing force for regionalisation amidst a host of regional processes and initiatives; as such it has found itself the object of critique as an institution and through the specific projects it has supported that have impacted on local communities and ecosystems. Meanwhile, local and NGO voices associated with the emergence of a vibrant civil society in Thailand and nascent civil society responses in neighbouring countries have challenged claims on resources made in the name of national development and regional integration.
This paper considers some key issues of re-scaling resource and environmental politics in the Mekong Region, and the extent to which challenges have been recast from national to regional development agendas. Politics of environment are shown to exist as a general rather than exceptional response to the region's development direction, and it is suggested that equitable and sustainable development increasingly needs to address simultaneously the re-scaling and reconfigurations of power in both environmental politics and the "infrapolitics" of environment. The paper is illustrated with case studies of dams in Laos and Thailand.  相似文献   
82.
Short-wave infrared reflectance spectra obtained from a Portable Infrared Mineral Analyser (PIMA) have been used to define alteration zones adjacent to base metal sulfide ore bodies at the Elura Mine, Cobar, Australia. The spectroscopic work identified white mica (sericite), chlorite and carbonates of hydrothermal origin in the alteration zones associated with the ore bodies. Weathering, alteration and ore zones can be discriminated by variations in the intensity and wavelength of relevant absorption features. Hydrothermal alteration is classified into four principal types, namely sericitic, silicic, chloritic and carbonate alteration. The first three types comprise overprinting hydrothermal assemblages of quartz, sericite, chlorite, ankerite, siderite, calcite and sulfides developed in strongly altered metasiltstone and slate of Early Devonian age, adjacent to the zinc–lead–silver mineralisation. An extensive zone of carbonate alteration, manifested as porphyroblasts of siderite in the host metasediments, is recognised beyond the zones of strong alteration. Spectral analysis is consistent with the mineralogical data obtained from XRD and XRF analyses and defines the limits of the alteration zones to distances of about 80 m around the ore bodies. The study demonstrates the potential for spectral analysis to assist with drill hole logging and the identification of alteration zones as part of mineral exploration and development programs.  相似文献   
83.
Diatom dissolution in saline lakes represents an important obstacle to the quantitative reconstruction of water chemistry and climate from lake sediment archives. This problem is here approached experimentally by artificially dissolving diatom-bearing core sediment from Lake Manyara, Tanzania. Manyara holds one of the longest continuous palaeolimnological records from tropical Africa although its interpretation is based on a fragmentary diatom record due to frustule dissolution. These experiments have revealed clear changes in assemblage composition as dissolution operated differentially with respect to diatom taxa. Differential dissolution has considerable impact on the water chemistry estimates derived from transfer functions. Taphonomy, rather than environmental change, may have been responsible for minor fluctuations in the diatom assemblages from Manyara, although major palaeohydrological changes during the Late Pleistocene and Early Holocene can be identified. Particularly well represented by MANE-87 is a period of intermediate lake level between 27 500 and 23 000 14C yr BP which has regional palaeohydrological significance.  相似文献   
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86.
Gravity anomalies and crustal shortening in the eastern Mediterranean   总被引:1,自引:0,他引:1  
Crustal shortening of the ocean floor in the eastern Mediterranean is recognized by a marked thickening of the sedimentary layer seaward of the Hellenic and Calabrian island arcs. Steep gradients and large negative free-air anomalies in the gravity field along with a highly uniform, low regional heat flow are manifestations of the thickened crust. Bodies of recently deformed sediment in and seaward of the Hellenic Trough reveal the style, polarity, and dynamics of the thickening mechanism.

A linear buried anticlinal structure, inferred from analysis of surface ship gravity profiles, may mark the site of contemporary intrabasinal underthrusting. The distribution of earthquakes beneath the Mediterranean Ridge supports the interpretation that the Anaximander, Ptolomy, and Strabo Mountains are features comparable to large basement nappes. Cyprus is one such structure, offset to the south, where the oceanic crust and part of the upper mantle have been involved in the décollement.  相似文献   

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88.
An 840-g specimen of the Bruderheim chondrite was subjected to magnetic and heavy-liquid mineral separation procedures, resulting in a number of chemically distinct samples. These samples were analyzed for cosmogenic Al26 by non-destructive gamma-gamma coincidence counting. The observed Al26 specific activities were correlated with the chemical composition of potential target elements by a weighted least-squares fitting technique. The calculated Al26 production rates, in dpm per kilogram of target element, are: Al, 1130 ± 190; Si, 245 ± 31; S, 133 ± 11; Mg, 28 ± 30. Production rates from Ca and Ni + Fe were estimated to be 24 and 2.2 dpm/kg, respectively, from spallation systematics.  相似文献   
89.
The 1928 eruption of Etna, Sicily, although the largest such event this century, has not been studied in detail. In this paper the nature of the eruption, the destruction it caused – including the complete devastation of the town of Mascali (pre-eruption population 2,000) – and emergency responses of the authorities to it are reviewed in the context of fascist politics and planning priorities. It is contended that, although at one level the response to the 1928 eruption was successful, at another fascism merely continued and enhanced a reactive, propitiatory approach to hazard mitigation. We argue that this legacy was not successfully overcome until the middle of the nineteen eighties. Finally contemporary Italian moves towards a more proactive approach to disaster planning, both generally and in the context of Etna, are discussed.  相似文献   
90.
The concentrations of major and trace elements have been determined in igneous rocks from Apollo 15. All materials analyzed have typical depletions of Eu except for minerals separated from sample 15085. Four samples have concentrations of trace elements that are similar to those of KREEP. The samples of mare basalt from Apollo 15 have higher concentrations of FeO, MgO, Mn, and Cr and lower concentrations of CaO, Na2O, K2O, and rare-earth elements (REE) as compared to the samples of mare basalt from Apollos 11, 12, and 14. The samples can be divided into two groups on the basis of their normative compositions. One group is quartz normative and has low concentrations of FeO while the other is olivine normative and has high concentrations of FeO. The trace element data indicate that the samples of olivine normative basalt could be from different portions of a single lava flow. At least two and possible three parent magmas can be identified from the samples of the quartz normative group on the basis of their concentration ratios of Sm to Eu. Within each group, the compositions of the samples appear to be related by crystallization of olivine or pyroxene. Significant variations of the ratio of concentration of Sm to Eu cannot be produced without plagioclase-liquid equilibrium. The source material of mare basalt may be depleted in Eu. Alternatively, the magmas may have assimilated a small volume of material similar to KREEP.Paper dedicated to Prof. Harold C. Urey on the occasion of his 80th birthday on 29 April 1973.  相似文献   
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