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Ministry of Energy Mines and Responsible for Core Review

GeoFile 2018-5

Regional moss-mat-sediment survey in the Porcher Island, Grenville Channel, and Dundas Island area, central British Columbia coast

R.E. Lett


Geofile 2018-5 describes a reconnaissance-scale moss mat-sediment geochemical survey carried out in 2000, in the Porcher Island, Grenville Channel, and Dundas Island areas of coastal British Columbia (NTS 103G, 103H, 103J). Seventy five moss mat-sediment samples were analyzed by a combination of a HNO3-HCl-H2O (modified aqua regia) dissolution - inductively coupled plasma emission/mass spectrometry and instrumental neutron activation, resulting in a total of 65 analytes. They were also analyzed for F and loss on ignition. Water samples were analyzed for pH, SO4, F, and U. The moss mat-sediment analyses reveal scattered Au anomalies that may reflect Cu-Mo sulphide mineralization on Porcher Island. Stronger Cu-Ag-V-Fe and Ba-Mo-Zn anomalies in streams draining the northeast part of Porcher Island, the central part of Porcher Island and along Grenville Channel can be explained by northeast-trending, metavolcanic-hosted, exhalative style magnetite and sphalerite-chalcopyrite mineralization. Only background Au, Cu, Pb and Zn values were found in the moss mat sediments collected from Dundas, Dunira and Melville islands.




View GeoFile 2018-5 (PDF, 10.3 MB)


Download Appendices A-E (Zip, Excel, 0.1 MB)


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