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Historical Archaeology - 相似文献
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Joseph R. Desloges 《The Canadian geographer》1990,34(2):98-109
Changes in the grain-size distribution and the lithologi-cal I mineralogical properties of sandy-gravel sediments are used to discriminate between sources for the alluvial valley-fill of Bella Coola River, coastal British Columbia. Spatially variable bedrock sources, ranging from highly resistant quartz monzonites to easily weathered basalts, yield sediments that reflect parent rock characteristics. Local increases in the D95 fraction of bulk gravel samples and the D50 fraction of sand samples can be related to inputs from steeper, heavily glaciated tributaries, or those underlain by fractured basalts of the Fraser Plateau. Where there are similarities in the grain-size properties of the source and the sampled deposit, however, grain-size information alone cannot be used to discriminate between sources. The lithology of Bella Coola alluvium shows a close correspondence with the general distribution of rock types in the basin, suggesting proportional contributions from most tributary sources over the long term. However, sand samples from the floodplain have a mostly volcanic affinity, indicating the dominance of sediment derived from headwater tributaries underlain by this rock type. Admixture of plutonic source sediments is evident in lower Bella Coola River adjacent to alluvial fans, heavily glaciated tributary creeks or rock walls comprised mainly of quartz monzonite. Les changements dans la granulometrie et les proprietes lithologiques et mineralogiques des sediments de gravel sablonneux servent d differencier les sources des depéts alluviaux de la Riviere Bella Coola sur la céte de la Colombie-Britannique. La variation spatiale des sources fondamentales donnent des sediments qui refletent les caracteristiques de la roche-mbe variant des quartz rnonzonites très résistants aux basaltes superficiellement altérés par les agents atmospheriques. Les augmentations locales dans la fraction D95 des echantillons de gravel et la fraction D50 des echantillons de sable peuvent être reliees la contribution des tributaires aux pentes plus escarpees et fortement glaciaires ou ceux qui traversent les basaltes fractures du Plateau Fraser. Cependant, quand il y a des similitudes dans la granulometrie de la source et le dépôt-échantillon, l'information granulometrique seule ne peut pas 6tre employee pour differencier les sources. La lithologie des alluvions de Bella Coola montre une correspondance avec la distribution générale des types de roches dans le bassin, suggérant des contributions proportionnelles des sources tributaires a long terme. Cependant, les échantillons de sable des plaines sujettes à inondations ont en grande part une affinité volcanique, indiquant que la dominance du sédiment provient des tributaires qui traversent ce type de roche. Une addition de sediments de sources plutonique est evidente dans le bas de la Riviere Bella Coola adjacent aux eventails alluviaux, aux ruisseaux tributaires affect& par une forte glaciation, ou aux murs de roches qui comprennent principalement des quartz monzonites. 相似文献
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Leith Deacon Silvia Sarapura Wayne Caldwell Sara Epp Miranda Ivany Jacob Papineau 《The Canadian geographer》2023,67(4):460-469
COVID-19 has caused enormous economic and social disruptions that may have lasting effects on employment, income, and working conditions. Critically, these disruptions often have a negative impact on mental health. While significant research has examined the relationship between COVID-19 and mental health, most of these studies focus on urban centres. This paper presents results from a pilot study conducted in two rural counties in Ontario, Canada on the experiences of residents from small and rural communities related to COVID-19. Based on 3496 survey results, this study quantifies the negative impact of COVID-19 on overall mental health and the confounding role of gender, income, and age. Results must be used to expand the dialogue around rural mental health and to ensure appropriate programs and policies are developed. 相似文献
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Joseph Shapiro 《政策研究杂志》1994,22(1):123-132
The Americans with Disabilities Act was pushed through Congress with far less attention from the media than has accompanied other major civil rights bills. This was part of a deliberate and unconventional strategy by disability rights lobbyists who believed that media portrayals of disability were so cliched that journalists would impede, not further, the public's understanding of disability rights issues. Despite the success of the strategy, there is a price to pay for having been a 'stealth' civil rights movement: Now that the law is in place, disabled people face a backlash from Americans who neither understand the ADA nor the need for civil rights protection for disabled people. 相似文献