Geochemical prospecting in peat terrains.

Pilot studies on a field area in Sutherland served to establish collective procedures to be used in subsequent work. Detailed sampling of peat was undertaken in the Lake District over an area of copper-lead- zinc mineralisation related to Drygill and Roughtongill mineral lodea Conventional peat augers were found to be unsuitable for the collection of large samples required for research, so a new sampler was designed and constructed which enabled 13cm diameter cores of peat to be readily collected. Experiments were devised to compare the standard techniques used in peat analysis. Results snowed that dry ashing and subsequent acid digestion of the peat ash was the neatest and most efficient total method of analysis, and emphasised the variability in results obtained by different analytical methods. After analysis of the Lake District samples by the total method, the use of partial extractants as reagents for cold extractable analysis V7as investigated. The experiments indicated that molar hydrochloric acid could be used as an extractant in a cold extractable method which was compatible with at niic absorption and colorimetric estimation techniques. A selection of the Lake District samples were then analysed by this method and it was noted that although the new method did not enhance the anomalies indicated by the total methods it still enabled them to be easily identified. Standard cumulative frequency interpretation techniques failed to provide a method for filtering background noise from the data, but this was thought to be due to the type of data, A new method of interpretation involving trend surface and semivariance analysis was highly successful in filtering out the background variation, and also provided data on the strike and length of the mineral veins. Residuals from the trend surface analysis plotted on the sample grid, illustrated the dominant strike of the mineralisation, and semivariance ellipses derived from the variograms described is direction by their long axes.