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Abstract: This paper explores different conceptual and policy spaces of wellbeing. The increasing use of wellbeing in contemporary health debates affords geographers of health new arena in which to explore the processes that promote, remedy or regenerate health and ill-health. The paper first critically reviews the theoretical approaches and challenges for operationalizing the concept of wellbeing in both research and policy. We then present a framework of the spaces of wellbeing to provoke discussion and research amongst geographers of health. The paper concludes with proposals for future research orientations. 相似文献
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新疆西准噶尔地区塔斯特岩体锆石LA-ICPMS年龄及其意义 总被引：3，自引：17，他引：3
西准噶尔萨吾尔地区地处新疆阿勒泰地区吉木乃县及塔城地区和丰县。酸性侵入岩在区内较发育,其研究对于准噶尔地区后碰撞构造-岩浆演化时限的厘定具有重要的意义。塔斯特岩体是萨吾尔地区重要的复式花岗岩体,与区内铜、金矿化关系密切。塔斯特岩体锆石 LA—ICPMS 年龄为337±4Ma(1σ),形成于早石炭世。结合已有的地球化学特征研究,这一年龄显示西准噶尔地区在早石炭世已处于后碰撞环境。本文获得的塔斯特岩体成岩年龄是目前在准噶尔地区获得的最老的后碰撞花岗岩锆石 U—Pb 年龄之一,为准噶尔地区后碰撞构造-岩浆演化时限的厘定提供了新的证据。 相似文献
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The oceanic substratum of Northern Luzon: Evidence from xenoliths within Monglo adakite (the Philippines) 总被引：2，自引：0，他引：2
Betchaida D. Payot Sebastien Jego Rene C. Maury Mireille Polve Michel Gregoire Georges Ceuleneer Rodolfo A. Tamayo Jr Graciano P. Yumul Jr Herve Bellon Joseph Cotten 《Island Arc》2007,16(2):276-290
Abstract A 8.65 Ma adakitic intrusive sheet exposed near Monglo village in the Baguio District of Northern Luzon contains a suite of ultramafic and mafic xenoliths including in order of abundance: spinel dunites showing typical mantle-related textures, mineral and bulk rock compositions, and serpentinites derived from them; amphibole-rich gabbros displaying incompatible element patterns similar to those of flat or moderately enriched back-arc basin basalt magmas; and amphibolites derived from metabasalts and/or metagabbros of identical affinity. A single quartz diorite xenolith carrying a similar subduction-related geochemical signature has also been sampled. One amphibolite xenolith provided a whole-rock K–Ar age of 115.6 Ma (Barremian). We attribute the origin of this suite to the sampling by ascending adakitic magmas of a Lower Cretaceous ophiolitic complex located at a depth within the 30–35 km thick Luzon crust. It could represent an equivalent of the Isabela-Aurora and Pugo-Lepanto ophiolitic massifs exposed in Northern Luzon. 相似文献
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Roberto Urrutia Alberto Araneda Fabiola Cruces Laura Torres Luis Chirinos Hans C. Treutler Nathalie Fagel Sebastien Bertrand Ingrid Alvial Ricardo Barra Emmanuel Chapron 《Limnologica》2007,37(1):49-62
Several lakes in Chile are near important volcanic areas where eruption impacts can limit the quality of lacustrine sediments for reconstructing past environmental changes. In this study, we report changes in diatoms, pollen, and chironomids assemblages after a tephra deposition in Lake Galletué (Chilean Andes). A sediment core obtained from Lake Galletué (40 m water depth) was sliced in 1 cm intervals and subsamples were taken to analyze each proxy. 210Pb and 137Cs activities were measured to obtain the geochronology and mineralogical analyses were performed to determine the mineral composition of the tephra. Diatom species composition and productivity were modified when the lake received the tephra; Aulacoseira granulata decreased and was later replaced by Cyclotella af. glomerata. After the tephra input, Aulacoseira granulata abundance increased to pre-disturbance levels and Cyclotella af. glomerata decreased. These changes seem to suggest a momentary increase in lake nutrient levels after the tephra deposition. Chironomid assemblages also decreased in head capsules just after the tephra deposition, but the most important change was the replacement of Ablabesmyia by Parakiefferiella, probably due to the sedimentological changes produced by the input of coarse tephra grains. Furthermore, unlike other studies, chironomid assemblages in Lake Galletué did not show a decrease drastically in diversity within the tephra layer. The pollen analysis indicated that, prior to the volcanic event, the vegetal community was dominated by Nothofagus sp., Araucaria araucana, and Blechnum sp.-type. After the tephra deposition, the same taxa are dominant, indicating that the volcanic event seems not produce changes in the vegetation. Nevertheless, within the tephra layer it is possible to see an increase in Poaceae, which represent – due to the percolation process – the effect of eruption on the vegetation. According to our results, diatoms were the most sensitive proxy for describing the changes produced by tephra deposition into the aquatic ecosystem and, despite the noticeable changes in its sedimentological properties; the lake seems to have a high resilience capacity, allowing it to return to pre-tephra input conditions. 相似文献
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Detecting co-seismic displacements in glaciated regions: An example from the great November 2002 Denali earthquake using SPOT horizontal offsets 总被引：1，自引：0，他引：1
Michael H. Taylor Sebastien Leprince Jean-Philippe Avouac Kerry Sieh 《Earth and Planetary Science Letters》2008,270(3-4):209-220
We use SPOT image pairs to determine horizontal offsets associated with the Mw 7.9 November 2002 Denali earthquake in the vicinity of Slate Creek, AK. Field measurements and aerial photographs are used to further characterize the geometry of the surface rupture. Aerial photographs show that shear localization occurs where the rupture trace is linear, and distributed off-fault deformation is common at fault bends and step-overs, or at geologic contacts between rock, glacial sediments, and ice. The displacement field is generated using a sub-pixel cross correlation technique between SPOT images taken before and after the earthquake. We identify the effects of glacier motion in order to isolate the tectonic displacements associated with the Denali earthquake. The resulting horizontal displacement field shows an along-strike variation in dextral shear, with a maximum of approximately 7.5 m in the east near 144° 52′W, which decreases to about 5 m to the west near 145° 45′W. If the November 2002 earthquake represents the long-term behavior of the Denali fault, it implies a westward decrease in the long-term dextral slip rate. A possible mechanism to accommodate the westward decreasing slip on the Denali fault is to transfer fault slip to adjacent east-trending contractional structures in the western region of the central Alaskan Range. 相似文献
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Alexandra Carriere Caroline Le Bouteiller Gregory E. Tucker Sebastien Klotz Mohamed Naaim 《地球表面变化过程与地形》2020,45(5):1085-1099
While it is well recognized that vegetation can affect erosion, sediment yield and, over longer timescales, landform evolution, the nature of this interaction and how it should be modeled is not obvious and may depend on the study site. In order to develop quantitative insight into the magnitude and nature of the influence of vegetation on catchment erosion, we build a landscape evolution model to simulate erosion in badlands, then calibrate and evaluate it against sediment yield data for two catchments with contrasting vegetation cover. The model couples hillslope gravitational transport and stream alluvium transport. Results indicate that hillslope transport processes depend strongly on the vegetation cover, whereas stream transport processes do not seem to be affected by the presence of vegetation. The model performance in prediction is found to be higher for the denuded catchment than for the reforested one. Moreover, we find that vegetation acts on erosion mostly by reducing soil erodibility rather than by reducing surface runoff. Finally, the methodology we propose can be a useful tool to evaluate the efficiency of previous revegetation operations and to provide guidance for future restoration work. © 2019 John Wiley & Sons, Ltd. 相似文献
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Fred Jourdan Sebastien Nomade Michael T. D. Wingate Ela Eroglu Al Deino 《Meteoritics & planetary science》2019,54(10):2573-2591
The Australasian tektites are quench melt glass ejecta particles distributed over the Asian, Australian, and Antarctic regions, the source crater of which is currently elusive. New 40Ar/39Ar age data from four tektites: one each from Thailand, China, Vietnam, and Australia measured using three different instruments from two different laboratories and combined with published 40Ar/39Ar data yield a weighted mean age of 788.1 ± 2.8 ka (±3.0 ka, including all sources of uncertainties) (P = 0.54). This age is five times more precise compared to previous results thanks, in part, to the multicollection capabilities of the ARGUS VI noble gas mass spectrometer, which allows an improvement of almost fourfold on a single plateau age measurement. Diffusion experiments on tektites combined with synthetic age spectra and Monte Carlo diffusion models suggest that the minimum temperature of formation of the Thai tektite is between 2350 °C and 3950 °C, hence a strict minimum value of 2350 °C. 相似文献