Critical parameters for economically viable metasandstone, Offerdal Nappe, Sweden

Abstract

Textural characteristics of a feldspathic metasandstone, the so-called Flammet Quartzite have been studied. This schistose metasandstone is quarried in the Lake Landögssjön area, Offerdal Nappe, Scandinavian Caledonides in the county of Jämtland, Sweden. The quarried section belongs to the lower part of the Upper Tectonostratigraphic Unit (UTU) in the Offerdal Nappe. Three metasandstones from subunits C, D, and E within the UTU have been compared. This was done on the basis of the frequency, thickness, and undulation of the cleavage domains. Subunit D has also been studied concerning plane persistency. It can be concluded that an average frequency of 4 cleavage planes/10 mm with a range of thickness between 0.5 and 1.5 mm, and an undulation of the cleavage plane of up to 0.5 mm is needed to produce an economical dimension stone used as building material. The cleavage plane persistency should be traceable for well over 5 m. With the present demand for production, only subunit D conforms to the textural prerequisite.

Key Words:

• Offerdal Nappe
• Flammet Quartzite
• Offerdalsskiffer
• dimension stone
• cleavage
• Caledonides
• Jämtland
• Sweden