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The article presents a case study on the influence of meltwater percolation on the seasonal isotopic signals in snow-pit sites located on Leffert Glacier, Prince of Wales Island, Nanavut, Canada. It investigates the evolution of snow temperature, water content, density and stable water isotopes of the area during early-season melt. Also provided are positive degree-day calculations to relate the amount of melt at the low-elevation snow-pit sites to the firn-core site.

The article discusses a study that aims to examine the effect of temperature and vapour trajectory controls on the stable-isotope signal in the winter snowpacks of the Rocky Mountains in Canada. The researchers used alpine snow-pit data from two alpine field sites at the Haig Glacier, Alberta and the Opabin Glacier in British Columbia. The snow pits that were taken from three different seasons were used to assess the effect of temperature. The study found that separation is driven by the mean temperature of each class and not a direct result of vapour pathway.

Fifty new Nd isotope analyses are presented from the North Bay area of the Grenville Province in Ontario. These data are used to map the extent of an allochthonous Grenvillian terrane which is an outlier of the Allochthonous Polycyclic Belt of the Grenville Province. Amphibolite facies orthogneisses from the allochthonous terrane have depleted mantle Nd model ages (T[subDM]) below 1.8 Ga, whereas the gneisses of the structurally underlying parautochthon, almost invariably have model ages above 1.8 Ga. The distribution of model ages is consistent with the distribution of distinct types of metabasic rock, used by other researchers as the criterion for recognizing rocks of the allochthonous and parautochthonous belts of the Grenville Province. The agreement between these different types of evidence demonstrates that Nd isotope mapping is a reliable and powerful tool for mapping terrane boundaries in high-grade metamorphic belts. [ABSTRACT FROM AUTHOR]