MINERAL EXPLORATION BENEATH TEMPERATE FORESTS - THE INFORMATION SUPPLIED BY TREES

Plants have a remarkable ability to select, use and store metals deriv ed from the substrate. Each species is unique in its requirements for and tolerances to the full spectrum of chemical elements in the Period ic Table. Studies to define the chemical characteristics of common tre es and shrubs of the temperate forest are providing insight to their u se for exploration, i.e., biogeochemical exploration. Examples of surv eys over gold deposits in British Columbia show the effectiveness of s ampling various tissues from different species in a range of biogeocli matic environments. At the Nickel Plate mine in the Montane-Spruce zon e, outer bark of Lodgepole pine was effective in defining a large area of metal enrichment; at the Carolin mine in the zone of Coastal Mount ain Hemlock, analysis of twigs of western hemlock and Pacific silver f ir provided an exploration target considerably larger than that define d by lithogeochemistry; at the Mount Washington gold deposit in the Mo untain Hemlock zone, twigs of mountain hemlock and rhododendron were u sed to outline the mineralization; and in the Interior Douglas-fir zon e at the QR deposit analysis of Douglas-fir tops collected by helicopt er provided a rapid and effective method of identifying a gold-rich ar ea.