An indicator mineral and geochemical case study was carried out around the Sisson W–Mo deposit to test modern indicator mineral and analytical methods and document glacial and fluvial dispersal from a significant W–Mo source. Indicator minerals in the 0.25 – 2.0 mm non-ferromagnetic heavy mineral fraction of till and stream sediments include the primary ore minerals scheelite, wolframite and molybdenite, as well as chalcopyrite, joseite, native Bi, bismutite, bismuthinite, galena, sphalerite, arsenopyrite, pyrrhotite and pyrite. Indicator minerals in c. 12 – 14 kg samples define glacial dispersal of at least 10 km down ice (SE) of the deposit and fluvial dispersal at least 4 km downstream. The presence of very coarse (0.5 – 2.0 mm) indicator minerals in till and stream sediments marks proximity (<1 km) to the mineralized source. Indicator elements for the deposit in the <0.063 mm fraction of till, the <0.177 mm fraction of stream sediments, and in stream water include W and Mo, and various combinations of pathfinder elements Ag, As, Bi, Cd, Cu, In, Pb, Te and Zn. This list of elements is more extensive than previously identified for the Sisson deposit or other studies around W mineralization in glaciated terrain. The study demonstrates that indicator mineral methods, so well known for diamond and gold exploration, have a broader application that includes W–Mo exploration.

A till composition study was carried out around the Sisson W-Mo deposit, one of the largest W deposits in the world, as part of the Geological Survey of Canadamp;gt;'s (GSC) Targeted Geoscience Initiative 4 (TGI-4), a collaborative federal geoscience program with a mandate to provide industry with the next generation of geoscience knowledge and innovative techniques that will result in more effective targeting of buried mineral deposits. This till geochemical study is one of the first detailed studies around a major W deposit in glaciated terrain. The &amp;lt;0.063 mm fraction of till clearly defines glacial dispersal at least 14 km down-ice of the deposit and this size fraction of till is recommended for W-Mo exploration in the region. Indicator elements for this type of W-Mo deposit include the ore elements W and Mo, and pathfinder elements Sn, Bi, Cu, Zn, Pb, Ag, In, As, Cd, Zn, and Te. A total digestion method, such as the one used in this study (lithium meta/tetraborare fusion/ICP-MS), is required to report the total concentration of W and Sn in till and aqua regia is suitable for determining the other pathfinder elements. Glacial dispersal of W and Mo from the Sisson deposit is detectable at a regional scale at least 14 km down-ice (southeast) using surface till sampling. A 2 km till sample spacing would be sufficient to detect the W dispersal train from a W-Mo deposit of this size.

Stream sediment and water samples were collected around the Sisson W-Mo deposit as part of the Geological Survey of Canada's (GSC) Targeted Geoscience Initiative 4 (TGI-4). The TGI-4 Program is a collaborative federal geoscience program with a mandate to provide industry with the next generation of geoscience knowledge and innovative techniques that will result in more effective targeting of buried mineral deposits. The stream sampling is part of an indicator mineral case study around the Sisson deposit to document indicator mineral signatures of the deposit in bedrock as well as surficial media (till and stream sediments). Stream sediments have been eroded from till, not from the Sisson deposit, thus patterns in stream sediments reported here reflect both glacial transport and fluvial transport. Indicator elements of the deposit in the &amp;lt;0.1 77 mm fraction of stream sediment are the main ore elements W and Mo and pathfinder elements include As, Bi, Ag, Cu, Zn, In, Tl, and Cd. A total analysis method (INAA) is required to determine the total concentration of W and Mo in stream sediments. Aqua regia/ICPMS is a suitable method for determining the content of the other pathfinder elements. Indicator/pathfinder elements in stream waters include As, Cd, Cu, Cs, W, and Zn. Indicator minerals of the deposit in the &amp;lt;2.0 mm heavy mineral fraction of stream sediments are the main ore minerals scheelite, wolframite, and molybdenite as well as other minerals including chalcopyrite, sphalerite, arsenopyrite, and pyrite. Fluvial dispersal of scheelite and wolframite from the deposit is detectable in stream sediments at least 4 km downstream from the north end of the deposit and 5 km southeast of the deposit in streams that drain the southeast-trending glacial dispersal train. Additional stream sediment sampling would be required to fully document the nature of dispersal of scheelite downstream from the deposit. Molybdenite is not a useful indicator mineral in stream sediments around the Sisson deposit because it is too soft to survive glacial and subsequent fluvial transport. A 2 km (4 km2) spacing of stream sediment samples is recommended to detect the W dispersal train from the Sisson deposit or similar styles of W-Mo mineralization.

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An indicator mineral case study was carried out around the Sisson W-Mo deposit, one of the largest W deposits in the world. The work was carried out as part of the Geological Survey of Canada's (GSC) Targeted Geoscience Initiative 4 (TGI-4), a collaborative federal geoscience program with a mandate to provide industry with the next generation of geoscience knowledge and innovative techniques that will result in more effective targeting of buried mineral deposits. This indicator mineral study is the first case study around a major W-Mo deposit in glaciated terrain. It is also the first indicator mineral case study in any terrain to identify a broad range of indicator minerals for this deposit type, in addition to the commonly known minerals scheelite and molybdenite. Indicator minerals for the Sisson W-Mo deposit include the primary ore minerals scheelite, wolframite, and molybdenite, as well as secondary ore minerals chalcopyrite, joseite, native Bi, bismutite, bismuthinite, galena, sphalerite, arsenopyrite, pyrrhotite, and pyrite. Indicator minerals in 10 kg till samples clearly define glacial dispersal at least 10 km down-ice (southeast) of the deposit. The presence of coarse (0.5-2.0 mm) indicator minerals indicates proximity (&amp;lt;1 km) to the source. Thus, the use of heavy mineral sampling in regional exploration programs for W-Mo deposits is recommended. A 2 km spacing of surface till samples is likely sufficiently dense to detect the glacial dispersal train from the Sisson deposit, as well as its polymetallic nature.