Blar i Artikler på forfatter "Heldal, Tom"
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A regional study of the dimension-stone potential in labradorite- bearing anorthositic rocks in the Rogaland Igneous Complex
Heldal, Tom; Lund, Bjørn (NGU Bulletin (427), Journal article, 1995) -
Building stone of central and southern Ethiopia: deposits and resource potential
Walle, Haileyseus; Heldal, Tom; Sintayehu, Zewde (NGU Bulletin (436), Journal article, 2000)The bedrock geology of Ethiopia exhibits a variety of rock types that can potentially be developed for building stone production. The ETHIONOR project has so far included investigation of such resources in the southern and ... -
Building-stone resources in Eritrea: results from introductory work in the NGU-EGS co-operation programme
Heldal, Tom; Yohannes, Ermias (NGU Bulletin (436), Journal article, 2000)Several building-stone quarries and prospects in Eritrea were visited during September 1998, as a part of the Norwegian.Eritrean ERINOR co-operation project. The bedrock geology of Eritrea comprises a variety of rocks, of ... -
Depositional environment and apparent age of the Fauske carbonate conglomerate, North Norwegian Caledonides.
Heldal, Tom; Fallick, Anthony E.; Gorokhov, Igor M.; Roberts, David; Melezhik, Victor A. (NGU Bulletin (436), Journal article, 2000)The Fauske conglomerate represents a rather rare case of a monomict carbonate conglomerate in the Late Neoproterozoic to Silurian, lithostratigraphic successions of the Norwegian Caledonides. Lithological varieties of this ... -
Fabrics and structure of metamorphic flagstones and implications for industrial quality
Heldal, Tom; Lund, Bjørn (NGU Bulletin (436), Journal article, 2000)Metamorphic flagstones are characterised by a regularly spaced mica foliation separated by quartzo-feldspathic domains, along which the rocks can be cleaved into commercial slabs. In the thrust nappes of the Scandinavian ... -
Natural stone in Norway: production, deposits and development
Heldal, Tom; Neeb, Peer-Richard (NGU Bulletin (436), Journal article, 2000)The natural stone industry has, during the last two decades, experienced a tremendous growth both on a global scale and within a Norwegian context. At the present time, the natural stone industry contributes significantly ... -
Ordovician stratigraphy in the western Helgeland Nappe Complex in the Brønnøysund area, North-central Norway.
Heldal, Tom (NGU Bulletin (438), Journal article, 2001)In the western part of the Helgeland Nappe Complex, a small ophiolite fragment (the Bolvær Complex) and a metasedimentary succession (the Brønnøysund Group) are exposed on several islands to the west of Brønnøysund. The ...