Review of till geochemistry and indicator mineral methods for mineral exploration in glaciated terrain

Appendix 5-Photo 1. Photograph of mountainous terrain in Fraser Plateau of south-central British Columbia, in western Canada. In this type of terrain, till can be sampled at higher elevations from thin till veneers (Tv) and thicker till blankets (Tb) on valley walls and from thick sediment sequences in valleys filled with till and alluvium (A), using overburden drilling. Appendix 5-Photo 2. Oblique photo showing an area affected by marine incursion near Baker Lake in Arctic Canada. The thick black dashed line indicates the inland limit of marine incursion. Till unmodified by wave action can be collected above this limit (west side of photo). Till surfaces topographically lower than this limit may be significantly reworked and winnowed by waves and be overlain by a bouldery mantle or beach shingles of poorly sorted debris (washed till). Raised beach sediments derived from winnowed till are not suitable sample sites because of significant reworking of till and significant transport distances of sediment in longshore currents. To the right side of the photo, where glaciomarine sediments are thick, till samples must be collected from beneath the cover sediments by digging holes or using deeper till sampling methods. Appendix 5-Photo 3. Oblique photo showing an area affected by glaciomarine incursion within the boreal forest near Gillam in central Canada. The white dashed line indicates the limit of glaciomarine incursion. Till unmodified by wave action can be collected above this limit (west side of photo). Till surfaces topographically lower than the marine limit may be significantly reworked and wave-washed and be overlain by a bouldery mantle, or beach shingles of poorly sorted debris (washed till). To the right side of the photo, where glaciomarine sediments are thick, till samples must be collected from beneath the sediments by digging holes or using other deeper till sampling methods. Photo by Michelle Gauthier.