Average lead isotope growth curves for shale-hosted zinc-lead deposits, Canadian Cordillera

Re-Os systematics and age of pyrite associated with stratiform Zn-Pb mineralization in the Howards Pass district, Yukon and Northwest Territories, Canada

“…However, many ages obtained by this approach are much older than their respective host rocks, and therefore such global growth curves should not be used to calculate model Pb ages (Leach et al 2005). A better approach involves the application of terrane-specific Pb growth curves, as was done for deposits in northern Australia ) and the Selwyn Basin (Godwin and Sinclair 1982). However, the underlying assumption in building these curves is that mineralization formed by syngenetic processes.…”

Summary results of the Glens Falls CUSMAP project, New York, Vermont, and New Hampshire

“…In contrast, lead isotopic values of galenas from individual carbonate-hosted, basemetal deposits in Ireland exhibit little heterogeneity (although there may be large differences between deposits), and the values are relatively unradiogenic compared to the Carboniferous age of the host rocks (Caulfield and others, 1986). Some shale-hosted, exhalative deposits of Canada, however, show a wider range of lead isotopic values than do the sedex deposits of Ireland (Godwin and Sinclair, 1982 (Shanks and others, 1987) also show a similar spread in lead isotopic composition. The marble-hosted Balmat zinc ores in the Grenvillian province of New York State recently have been described as a metamorphosed MVT deposit (Whelan and others, 1984), and galenas from Balmat, like those from Lion Hill, are isotopically heterogeneous.…”

“…Average lead isotope growth curves for sedex-type mineral deposits have been empirically derived for a number of specific, well-defined tectonic environments. For example, Godwin and Sinclair (1982) have constructed an average lead isotope growth curve for shale-hosted, zinclead deposits of the Canadian Cordillera. The model has been used to date a number of sedex deposits in the Selwyn basin and in the Ogilvie, Richardson, Wernecke, and Mackenzie Mountains of western Canada.…”

Investigation of Past and Present Multi-metal Input along Two Highways of British Columbia, Canada, Using Lead Isotopic Signatures

“…Simonetti et al (2003) reported that isotopic ratios for lichens in western Canada (which ranged in location from the Arctic circle, all the way down to the Canada-USA border) could be grouped in a triangular area marked by the influence of American Pb ores, B.C. ores and natural isotopic signatures from the Canadian Cordillera (Godwin and Sinclair 1982). It can be seen that the authors proposed triangular area, reproduced in Fig.…”

“…American and Canadian gas values from Sturges and Barrie (1987). Natural Pb isotopic signatures according to values reported by Godwin and Sinclair (1982) isotopic composition ( 206 Pb/ 207 Pb ≤ 1.17). These results would put the majority of atmospheric and soil samples collected from the highway study sites in the anthropogenic-activity-influenced range.…”