| Autor: |
Sarala, P., Rossi, S., Peuraniemi, V., Ojala, V. J. |
| Předmět: |
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| Zdroj: |
Transactions - Institution of Mining & Metallurgy. Section B. Applied Earth Science; Mar2007, Vol. 116 Issue 1, p22-36, 15p, 3 Diagrams, 1 Graph, 5 Maps |
| Abstrakt: |
In glaciated terrains, the knowledge of Quaternary geology is essential for successful exploration. In Finland, the bedrock is almost completely covered by till of variable composition, thickness and stratigraphy, as well as various types of moraine formations from recent glaciations. In this study, the morphological, stratigraphical and compositional investigations of till and moraines in southern Finnish Lapland were combined with heavy mineral and geochemical studies to trace mineralised sources in the bedrock. In the study area, the glacial morphology is composed of an assemblage of transversal ribbed moraines and longitudinal drumlins and flutings with gently undulating till cover in between. In places, weathered bedrock remnants are preserved beneath the till cover and can be useful sampling media for exploration. The ribbed moraine ridges are the most favourable moraine type for exploration. Short glacial transportation of debris and boulders in the upper till and surface of the ridges is advantageous for tracing the ore indicators. Local bedrock indication is another aspect that makes sampling easy and minimises costs. In the areas of drumlins, flutings and thin till cover, transport distances are usually long and the possibility of complex glacial transportation increases. If weathered bedrock material is mixed in the till, it makes an interpretation of till geochemical data difficult; background values are usually elevated and anomalous values coming from fresh bedrock sources might be obscured. However, the sampling of the weathered bedrock provides indications of the local geochemical features in the bedrock. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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