A fast method for the direct analysis of soils, namely solid sampling (SS) electrothermal vapourization inductively coupled plasma atomic emission spectrometry (ETV-ICP-AES), was validated through the accurate analysis of a soil standard reference material (SRM) using another soil SRM as a calibration standard and an Ar emission line as internal standard to compensate for sample loading effects on the plasma. Good agreement was obtained between the measured concentrations and certified values according to a Student’s t-test. The validated method was applied to the determination of the distribution of elements in depth profile soil samples from across the Talbot Lake VMS Cu-Zn prospect, in the Flin Flon-Snow Lake terrane, Manitoba, Canada. These profiles revealed that: Zn, P and Ag had anomalously high concentrations at 20–50 cm depth at 400 m, above where the easternmost part of the ore deposit is located along a 0–1000 m sampling line; Cu, Al, Ba, Pb and Hg were concentrated on the surface and at 40-cm depth mostly between 500 and 600 m; and Cl, Br and I were concentrated at depth at 400 m and over all depths at 600 m. As the geochemical anomaly is known to lie from 400 to 600 m, all these elements could be used to locate the ore. Good agreement was obtained with results by ICP mass spectrometry (ICP-MS) following aqua regia (AR) digestion, for those elements that could be determined by ICP-MS. In fact, not only is sample dissolution unnecessary but qualitative analysis by SS-ETV-ICP-AES is sufficient to obtain depth profiles, including for elements like Cl, which cannot be determined when AR is used for digestion.
- Geochemical exploration
- electrothermal vapourization (ETV)
- inductively coupled plasma atomic emission spectrometry (ICP-AES)
- solid sampling
- vertical element migration
- soil fraction
- geochemical anomaly
- Received July 30, 2013.
- Accepted August 30, 2013.
- © 2014 AAG/Geological Society of London