Portal de Periódicos da CAPES

Fifty-one chemical elements in till from the Oppdal region, Mid-Norway: relation to mineralization, Quaternary and bedrock geology

2018; Zoological Society of London; Volume: 18; Issue: 3 Linguagem: Inglês

10.1144/geochem2017-096

2041-4943

Malin Andersson, Ola A. Eggen, Deta Gasser, Clemens Reimann, Fredrik Høgaas, Bjørgunn H. Dalslåen,

Hydrocarbon exploration and reservoir analysis

The study presents data from a geochemical till survey conducted in the Oppdal/Berkåk area of Central Norway. Using a 1 × 2.5 km grid, 877 samples were taken to cover a 2000-km 2 survey area (one site per 2.2 km 2 ). The samples were air dried, sieved to <2 mm and analysed for 51 elements following an aqua regia extraction. A number of geochemical anomalies, related to lithology, a prominent fault zone, mineralization or environmental processes, are delineated for a large number of elements. Four main anomalies are outlined. A large, elongated (40 km long) multi-element anomaly is associated with normal faults and adjacent rhyolitic-andesitic rocks occurring in the area. Elements associated with gold (As, Sb) form an anomaly on the central high-altitude area just to the east of the fault related anomaly. Two further areas that display high concentrations for many elements are located around Orkelsjøen and Soknedal. Climatic/topographic conditions have a strong influence on the Hg and Se distribution. Several areas that display geochemical anomalies, where more detailed studies could be conducted were also identified. Supplementary material: Geochemical maps for all elements, boxplots showing till samples grouped in tectonic units, and boxplots showing till samples grouped by main lithologies are available at https://doi.org/10.6084/m9.figshare.c.4038950