Organic Centre-Lake Sediments-Application in the Geochemical Exploration for Gold in the Canadian Shield of Saskatchewan

Special Volume, Vol. SV 24, No. 1982, 1982

Preliminary investigations indicate that organic lake sediments offer some potential for gold exploration within the Canadian Shield of northwestern Saskatchewan. It is also apparent that certain precautions must be taken. Gold is primarily related to the organic fraction of the lake sediments, which, although giving consistant Au contents to those sediments, may restrict the dispersion of Au within the lake itself. It may be necessary to carry out selective extractions on the lake sediments to differentiate between Au related to organic sequestration, indicative of hydromorphic and/ or chemical dispersion, and Au related to inorganics, indicative of mechanical dispersion. Lake sediments are probably only of use for very detailed exploration (i.e. every lake). One to three samples per lake should be appropriate, although a single centre-lake organic-rich sediment sample may be adequate in very small lakes. Each lake sediment sample should be analyzed at least twice and the analytical data carefully monitored and evaluated. The use of As in lake sediments as a pathfinder element for gold is applicable in the search for certain types of gold occurrences. Following detailed lake sediment sampling, basal till sampling can possibly be used to localize areas of potential gold with or without base metal mineralization.

Keywords: gold, gold mining, Organic Centre-Lake Sediments-Application, geochemical exploration, Canadian Shield, Lake sediments