Radiogenic heat production analysis of Fennoscandian Shield and adjacent areas in Sweden

Show full item record



Permalink

http://hdl.handle.net/10138/303226

Citation

Veikkolainen , T H K , Kukkonen , I T & Näslund , J-O 2019 , ' Radiogenic heat production analysis of Fennoscandian Shield and adjacent areas in Sweden ' , Geophysical Journal International , vol. 218 , no. 1 , pp. 640-654 . https://doi.org/10.1093/gji/ggz186

Title: Radiogenic heat production analysis of Fennoscandian Shield and adjacent areas in Sweden
Author: Veikkolainen, Toni Henri Kristian; Kukkonen, Ilmo Tapio; Näslund, Jens-Ove
Contributor: University of Helsinki, Department of Geosciences and Geography
University of Helsinki, Department of Geosciences and Geography
Date: 2019-07
Language: eng
Number of pages: 15
Belongs to series: Geophysical Journal International
ISSN: 0956-540X
URI: http://hdl.handle.net/10138/303226
Abstract: In northern Europe, radiogenic heat production of surface rocks has been extensively studied in Finland and Norway alike. This paper presents a heat production analysis of Sweden, based on a rock outcrop data compilation obtained from the Geological Survey of Sweden (SGU). The study area comprises Precambrian Shield, Caledonian and platform cover areas. Altogether 39933 samples with uranium, thorium and potassium concentration (C-U, C-Th and C-K) and density () data were available. Heat production (HP) was calculated using raw point data, binning on a regular grid, and averaging by bedrock units in the geological map. Methods based on raw point data and grid-based binning resulted in HP values of 2.5 +/- 4.1 and 2.5 +/- 5.6 Wm(-3), respectively, while averaging by lithology produced a lower value of 2.4 +/- 1.7 Wm(-3). Limiting the lithology-based averaging to Precambrian bedrockareas resulted in heat production of 2.4 +/- 1.6 Wm(-3). Due to the small geographic extent of area covered by sediments, this is similar to the Precambrian-only value. Regardless of the calculation method, heat production in Sweden is considerably higher than the corresponding value for Finland. The Swedish platform cover had apparently the lowestheat production (1.0 +/- 1.8 Wm(-3)) of all units but the presence of Precambrian rocks below the sediments means that this value strongly misleads if used to represent the entire upper crust. Svecokarelian (Svecofennian) and Sveconorwegian rocks, which comprised 94.0 per cent of all individual observations, had heat production values of 2.6 +/- 1.8 and 1.7 +/- 1.4 mu Wm(-3), respectively. Although the Swedish data still have large spatial gaps when compared to Finnish data, most bedrock units in Sweden are covered. It is obvious that the higher heat flow of Sweden compared to that of Finland is caused by near-surface (i.e. upper crustal) heat production, and crustal differentiation in Sweden is also larger.
Subject: 1171 Geosciences
Composition and structure of the continental crust
Heat flow
Europe
Spatial analysis
Cratons
Crustal structure
PERMIAN GEOLOGICAL PROVINCES
U-PB
FLOW DATA
LITHOSPHERE
FINLAND
NORWAY
ROCKS
AGE
GEOCHEMISTRY
STRATIGRAPHY
Rights:


Files in this item

Total number of downloads: Loading...

Files Size Format View
ggz186.pdf 14.20Mb PDF View/Open

This item appears in the following Collection(s)

Show full item record