| Title | Regional and local-scale gold grain and till geochemical signatures of lode Au deposits in the western Abitibi Greenstone Belt, central Canada |
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| Author | McClenaghan, M B |
| Source | Drift exploration in glaciated terrain/Drift exploration in glaciated terrain; by McClenaghan, M B (ed.); Bobrowsky, P T (ed.); Hall, G E M (ed.); Cook, S J (ed.); Geological Society, Special Publication 185, 2001 p. 201-224, https://doi.org/10.1144/gsl.sp.2001.185.01.09 |
| Year | 2001 |
| Alt Series | Geological Survey of Canada, Contribution Series 1999185 |
| Publisher | Geological Society of London |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Ontario; Quebec |
| NTS | 31L/10; 31L/11; 31L/14; 31L/15; 31M; 31N/11; 31N/12; 31N/13; 31N/14; 32C/03; 32C/04; 32C/05; 32C/06; 32C/11; 32C/12; 32C/13; 32C/14; 32D; 32E; 32F; 41P/09; 41P/10; 41P/11; 41P/12; 41P/13; 41P/14; 41P/15;
41P/16; 42A; 42H |
| Area | Timmins; Matheson; Kirkland Lake; Rouyn-Noranda; La Sarre; Val-d'Or; Matagami; Lake Abitibi; Otisse Lake; Peterlong Lake; Radisson Lake |
| Lat/Long WENS | -82.0000 -76.0000 50.0000 46.5000 |
| Subjects | geochemistry; surficial geology/geomorphology; economic geology; gold geochemistry; drift prospecting; till geochemistry; glacial deposits; gold, native; sampling methods; grain size analysis; dispersal
patterns; Archean; metavolcanic rocks; metasedimentary rocks; intrusive rocks; fracture filling deposits; inclusions; tills; glaciolacustrine deposits; till stratigraphy; peatlands; till samples; geochemical surveys; Wisconsinian glacial stage;
exploration methods; mineral exploration; drilling; geochemical analyses; till stratigraphy; quartz veins; sulphides; sediment transport; source rocks; anomalies; tholeiites; mafic rocks; pebble counts; sands; gravels; clays; silts; glaciofluvial
deposits; pyrite; volcanic rocks; diabases; mafic metavolcanic rocks; ultramafic metavolcanics; Abitibi Greenstone Belt; Destor-Porcupine fault zone; Larder Lake-Cadillac fault zone; Matheson Till; Owl Creek beds; Owl Creek gold deposit; Golden Pond
gold deposit; Pamour deposit; Matachewan golddeposit; Hislop deposit; Laurentide Ice Sheet; Lake Ojibway; Gowganda Formation; Young-Davidson gold deposit; dispersal trains; Quaternary; Precambrian |
| Illustrations | sketch maps; block diagrams; flow charts; secondary electron images; histograms; graphs; tables; profiles; photographs |
| Released | 2001 01 01 |
| Abstract | This paper is an overview of drift exploration methods for lode Au deposits in areas of thin and thick cover of glacial sediments within the Abitibi Greenstone Belt of central Canada. It summarizes a
large volume of data produced by government regional surveys and case studies as well as that from industry-led gold exploration programs. Regional till surveys can be used as targeting mechanisms for further Au exploration. Anomalies are defined by
a series of samples with elevated Au concentrations that lie along significant bedrock structures, occurring in clusters or as isolated samples in areas of low sample density. Thresholds between background and anomalous Au grain abundances or Au
concentrations are variable and depend on location within the Abitibi Greenstone Belt. Case studies around known deposits provide examples of geochemical and mineralogical signatures of Au deposits that can be expected in till down-ice. These serve
as sources of information on appropriate sampling methods and size fractions to analyse, and on ice flow patterns, local glacial stratigraphy and suitable till units for sampling. Two methods for measuring the Au content of till are commonly used:
(1) a count of visible Au grains and (2) geochemical elemental analysis. Close to source, till contains thousands to hundreds of thousands ppb Au and several hundred Au grains. The Au grains vary from coarse sand to silt sizes and have pristine
shapes. The presence of high Au concentrations in till indicates that the ore zones subcrop and that glacial processes have produced Au dispersal trains down-ice. |
| GEOSCAN ID | 210994 |
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