| Title | Regional-scale lake-sediment sampling and analytical protocols with examples from the Geological Survey of Canada |
| Download | Not digitized yet. Request a scan of publication |
| |
| Author | Bourdeau, J E ;
Dyer, R D |
| Source | Geological Survey of Canada, Open File 8980, 2023, 41 pages, https://doi.org/10.4095/331911  Open Access |
| Image |  |
| Year | 2023 |
| Publisher | Natural Resources Canada |
| Document | open file |
| Lang. | English |
| Media | on-line |
| Related | NRCan
photo(s) in this publication |
| File format | pdf |
| Province | Canada; Canada; British Columbia; Alberta; Saskatchewan; Manitoba; Ontario; Quebec; New Brunswick; Nova Scotia; Prince Edward Island; Newfoundland and Labrador; Northwest Territories; Yukon;
Nunavut |
| NTS | 1; 2; 3; 10; 11; 12; 13; 14; 15; 16; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 52; 53; 54; 55; 56; 57; 58; 59; 62; 63; 64; 65;
66; 67; 68; 69; 72; 73; 74; 75; 76; 77; 78; 79; 82; 83; 84; 85; 86; 87; 88; 89; 92; 93; 94; 95; 96; 97; 98; 99; 102; 103; 104; 105; 106; 107; 114O; 114P; 115; 116; 117; 120; 340; 560 |
| Lat/Long WENS | -141.0000 -50.0000 90.0000 41.7500 |
| Subjects | geochemistry; mineralogy; lake sediments; geochemical surveys; stream sediment geochemistry; stream sediment samples; geological research |
| Illustrations | figures; schematic representations; photographs; schematic sections; tables; screen captures; schematic diagrams; profiles; plots |
| Program | GEM-GeoNorth: Geo-mapping for Energy and Minerals GEM Program Coordination |
| Released | 2023 07 04 |
| Abstract | Regional-scale lake sediment surveys have been successfully used since the 1970s as a means for reconnaissance geochemical exploration. Lake sediment sampling is typically performed in areas with a lack
of streams and an overabundance of small-sized (=5 km across) lakes. Lake sediments are known to have major, minor and trace element concentrations that reflect the local geology. Overall, lake sediment surveys are planned and conducted following
four distinct stages: 1) background research, 2) orientation survey, 3) regional survey, and 4) detailed survey. At the Geological Survey of Canada, samples are usually collected from a helicopter with floats. Sample density ranges from 1 sample per
6 - 13 km2. Samples are collected from the centre of the lake using a gravity torpedo sampler which corresponds to a hollow-pipe, butterfly bottom-valved sampler attached by a rope to the helicopter. Collected sediment samples are then placed in
labelled bags and left to air dry. Detailed field notes and additional samples (field duplicates), for the purpose of an adequate quality assurance and quality control program, are also taken. Samples are then milled and sent to analytical
laboratories for element determination. Commonly used analytical methods include: X-ray fluorescence (XRF), atomic absorption spectroscopy (AAS), inductively coupled plasma-atomic emission spectrometry (ICP-AES) and -mass spectrometry (ICP-MS),
instrumental neutron activation analysis (INAA), and/or determination of volatile compounds and organic carbon using Loss on Ignition (LOI). Analytical data is first evaluated for quality (contamination, accuracy and precision). Numerous options for
the analysis of lake sediment data exist, ranging from simple basic element concentration maps and statistical graphical displays together with summary statistics, to employing multivariate methodologies, and, more recently, using machine learning
algorithms. By adopting the set of guidelines and examples presented in this manual, scientific researchers, exploration geologists, geochemists and citizen scientists will be able to directly compare lake sediment datasets from anywhere in Canada.
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| Summary | (Plain Language Summary, not published)
Regional-scale lake sediment surveys have been successfully used since the 1970s for geochemical exploration. Lake sediment sampling is typically
performed in areas with a lack of streams and an overabundance of small-sized (=5 km across) lakes. Lake sediments are known to have element concentrations that reflect the local geology. At the Geological Survey of Canada, samples are usually
collected from a helicopter with floats. Sample density ranges from 1 sample per 6 - 13 km2. Samples are collected from the centre of the lake using a sampler attached by a rope to the helicopter. Collected sediment samples are then placed in
labelled bags and left to air dry. Samples are then milled and sent to analytical laboratories for element determination. Analytical data is first evaluated for quality (contamination, accuracy and precision) and then interpreted using a number of
available methods. By adopting the set of guidelines and examples presented in this manual, scientific researchers, exploration geologists, geochemists and citizen scientists will be able to directly compare lake sediment datasets from anywhere in
Canada. |
| GEOSCAN ID | 331911 |
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