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211.
When Britain assumed responsibility for the French Colonies in North America (1763) the French (francophones) were concentrated in the St. Lawrence Lowlands. Subsequent settlements by British and American colonists (anglophones) were guided by government policy, economic opportunities, and political events. The outcome was a mixture of anglophone settlers initially, as intended, developing around the lowland French but subsequently evolving to a peripheral location. Crowded conditions forced the francophones to move into this peripheral area as well. Through these processes a cultural zone of transition evolved between Quebec and her neighbouring provinces. Contact between the two ethnic groups within this zone, however, has not led to integration but moreso to a cultural division. In this situation it has been generally the francophone who has accommodated to the anglophone for required social and vocational interaction. Through the application of the index of language intensity assessment of the impact of recent sociopolitical policies upon this traditional pattern has been made. In the past decade anglophones have been leaving Quebec at an accelerated rate. Those remaining have an opportunity to increase the processes of interaction and integration with the francophone society and, it is theorized, will do so if a negative attitude among the youth toward a future in the province can be overcome.  相似文献   
212.
Determination of Horizontal Aquifer Anisotropy with Three Wells   总被引:2,自引:0,他引:2  
Existing methods for the determination of horizontal aquifer anisotropy by means of pumping tests require a minimum of four wells, one for water withdrawal and three for drawdown observations. This paper shows how the same methods can be used to determine anisotropy with as few as three wells, if at least two of them can be pumped in sequence. A field example is included. A method of analyzing data from more wells than the above minimum, by least squares, is also described.  相似文献   
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In recent decades, significant changes of Arctic sea ice have taken place. These changes are expected to influence the surface energy balance of the ice-covered Arctic Ocean. To quantify this energy ba...  相似文献   
217.
Journal of Seismology - Site response is a critical consideration when assessing earthquake hazards. Site characterization is key to understanding site effects as influenced by seismic site...  相似文献   
218.
This article presents a methodological model for the study of the space‐time patterns of everyday life. The framework utilizes a wide range of qualitative and quantitative sources to create two environmental stages, social and built, which place and contextualize the daily mobilities of individuals as they traverse urban environments. Additionally, this study outlines a procedure to fully integrate narrative sources in a GIS. By placing qualitative sources, such as narratives, within a stage‐based GIS, researchers can begin to tell rich spatial stories about the lived experiences of segregation, social interaction, and environmental exposure. The article concludes with a case study utilizing the diary of a postal clerk to outline the wide applicability of this model for space‐time GIS research.  相似文献   
219.
A key requirement for any model of mantle evolution is accounting for the high 3He/4He ratios of many ocean island basalts compared to those of mid-ocean ridge basalts. The early, popular paradigm of primitive, undegassed mantle stored in a convectively isolated lower mantle is incompatible with geophysical constraints that imply whole mantle convection. Thus it has been suggested more recently that domains with high 3He/U ratios have been created continuously from the bulk mantle throughout Earth history. Such models require that the 3He/4He ratio of the convecting mantle was at least as high as the highest values seen in OIB at the time the OIB source was generated. These domains must also be created with sufficient He to impart distinctive He isotopic signatures to ocean island basalts. However, the He isotope evolution of the mantle has not been consistently quantified to determine if such scenarios are plausible.

Here a simple model of the He evolution of the whole mantle is examined. Using a wide range of possible histories of continental extraction and He degassing, the bulk convecting mantle was found to have had 3He/4He ratios as high as those seen in the Iceland hotspot only prior to 3 Ga. Such high 3He/4He ratios can only be preserved if located in domains that are not modified by convective mixing or diffusive homogenisation since that time. Further, there are difficulties in producing, with commonly invoked magmatic processes, domains with sufficiently high 3He/U ratios and enough 3He to be able to impart this signature to ocean island basalts. The results are consistent with models that store such He signatures in the core or a deep layer in the mantle, but are hard to reconcile with models that continuously generate high 3He/4He domains within the mantle.  相似文献   

220.
Wireline logs and vertical seismic profile data were acquired in two boreholes intersecting the main mineralized zone at the Cu–Au New Afton porphyry deposit, Canada, with the objectives of imaging lithological contacts, fault zones that may have acted as conduits that channelled the mineralization, and alteration zones. Log data provide physical rock properties for the main lithologies and alteration zones. Calliper logs reveal many faults and caved-in zones generally indicating rocks with low integrity at the borehole wall. The preponderance of these zones, as indicated by the logs, suggests that their response may dominate the seismic-reflection wavefield. Outside fault zones, compressional and shear-wave velocities exhibit significant variability due to porosity, the heterogeneity of volcanic fragmental rocks and alteration. Distributed acoustic sensing was used to acquire vertical seismic profiling data in the two boreholes surveyed with wireline logs. Straight and helically wound fibre-optic cables housed standard fibres and a fibre engineered to increase the intensity of backscattering at the distributed acoustic sensing interrogator. Standard and engineered optical fibres placed in the two boreholes were daisy-chained together to form two 5-km-long continuous fibres that were interrogated at once with two interrogators. A new generation of interrogator connected to the engineered fibres provided field data with lower noise level and higher signal-to-noise ratio. These data with higher signal-to-noise ratio from straight fibre-optic cable were processed and used for depth imaging. Depth images benefitted from new migration weights that account for the directional sensitivity of the straight fibre-optic cable and limit the extent of migration artefacts. Migration results show several reflectors with shallow dips to the northwest, some explained by faults intersecting the surveyed boreholes. The main sub-vertical lithological and alteration contacts at New Afton generated downgoing reflections that were not considered in the migration.  相似文献   
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