Browsing NGU-publikasjoner by Author "Roberts, David"
Now showing items 21-40 of 67
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Geochemistry and palaeogeographical setting of greenstone units on Frosta peninsula, Nord-Trøndelag, Central Norwegian Caledonides
Lippard, Stephen J.; Roberts, David (NGU Bulletin (450), Journal article, 2010)Volcanic and high-level intrusive rocks of the Støren Nappe exposed on the west coast of Frosta peninsula occur in two, distinct, magmatic units; the bimodal Fånes complex and the metabasaltic Granheim greenstone. North ... -
Geochemistry and petrogenesis of trondhjemites and granodiorite from Gauldalen, Central Norwegian Caledonides
Pannemans, Bart; Roberts, David (NGU Bulletin (437), Journal article, 2000)In the Gauldalen district of Central Norway, three varieties of trondhjemite cutting rocks of the Gula Complex have been distinguished on the basis of nuances of colour and field relationships. The high Al2O3, Rb and Sr, ... -
Geochemistry and Rb-Sr dating of the Muruvik rhyolite tuff, Trondheimsfjord, Central Norway.
Roberts, David (NGU Bulletin (412), Journal article, 1988)A geochemical study of a low greenschist facies, felsic lapill-ash tuff fromnear the stratigraphic top of the Ordovician Lower Hovin Group at Muruvik,Trondheimsfjord, has shown that the pyroclastite is clearly calc-alkaline ... -
Geochemistry and Rb-Sr dating of trondhjemite dykes from the Gula Group, near Snøan, Sør-Trøndelag.
Roberts, David; Sundvoll, Bjørn (NGU-Rapport (96.163), Report, 1996)Trondhjemite dykes forming part of a swarm cutting the Gula Group metasedimentsand tectonically overlying Støren Group metabasalts in the district south ofStøren, Sør-Trøndelag, have been investigated in road-cuts in the ... -
Geochemistry and Rb-Sr isochron age of trondhjemite dykes from the Gula Complex, near Snøan, Central Norway.
Sundvoll, Bjørn; Roberts, David (NGU Bulletin (437), Journal article, 2000)Trondhjemite dykes trending c.ENE-WSW and transecting early metamorphic fabrics in rocks of the Gula Complex south-southwest of Støren, are themselves weakly metamorphosed and foliate. Geochemical data show that the dykes ... -
Geochemistry of dolerite and metadolerite dykes from Varanger Peninsula, Finnmark, North Norway.
Roberts, David (NGU (322), Journal article, 1975)Dolerite dykes provide the only manifestation of igneous activity in the thick, Riphean to Lower Cambrian, weakly metamorphosed sedimentary sequence of Varanger Peninsula. Major and trace element abundances and ratios from ... -
Geochemistry of mafic dykes in the Corrovarre Nappe, Troms, North Norway
Roberts, David (NGU Bulletin (419), Journal article, 1990)Tholeiitic metadolerite dyke rocks in the Corrovarre Nappe of the Kalak Nappe Complex in North Troms show chemical traits which indicate T-MORB affinities, with fairly flat, chondrite-normalised REE patterns in a (La\/Nb)N ... -
Geokjemiske og mikrostrukturelle trekk som ledsager mylonittisering langs den vestlige randen av Bindalsbatolitten, Nord-Trøndelag
Roberts, David; Nissen, August L. (NGU-Rapport (96.164), Report, 1992)Et geokjemisk studium er foretatt av endeledd tilknyttet mylonittiseringen av en granitt-protolitt tilhørende Bindalsbatolitten, like øst for Kongsmoen, Nord-Trøndelag. Mylonittiseringen viser flere teksturelle og strukturelle ... -
Geological investigations in the Snåsa-Lurudal area, Nord-Trøndelag.
Roberts, David (NGU (247), Journal article, 1967)Metasediments and meta-volcanic rocks of supposed Middle Ordovician age overlying a basement complex consisting predominantly of granite-gneisses, are described from an area near the north-eastern end of the lake Snåsavatn. ... -
Geological note: Age of the Hamningberg dolerite dyke, Varanger Peninsula, Finnmark: Devonian rather than Vendian - a revised enterpretation
Roberts, David (NGU Bulletin (451), Journal article, 2011)In an earlier geochronology paper in this same journal, discordant U-Pb ages on zircons from a dolerite dyke near Hamningberg, Varanger Peninsula, Finnmark, were interpreted to favour a Vendian (Ediacaran) age of intrusion ... -
Geologisk og strukturgeologisk kartlegging for Jernbaneverket Utbygging i Asker og Bærum
Solli, Arne; Braathen, Alvar; Roberts, David; Nordgulen, Øystein; Lutro, Ole (NGU-Rapport (98.124), Report, 1998)NGU har på oppdrag for Jernbaneverket Utbygning utført geologisk kartlegging og strukturgeologiske undersøkelser i området langs planlagt jernbanetrase fra Skøyen via Sandvika til Asker. På grunnlag av tilgjengelige data ... -
Geology and petrochemistry of the Smøla-Hitra Batholith, Central Norway.
Roberts, David; Gautneb, Håvard (NGU Bulletin (416), Journal article, 1989)The plutonic rocks which compose the Smøla-Hitra Batholith (SHB) cover an exposed area of c.1000 km\u00B2 and intrude folded, Arenig-Llanvirn, low-grade meta-sedimentary and bimodal metavolcanic rocks and higher-grade ... -
Geology of the Båtsfjordfjellet drillcore, Varanger Peninsula, Finnmark, northern Norway
Siedlecka, Anna; Roberts, David (NGU Bulletin (452), Journal article, 2012)Logging of >800 metres of drillcore from a borehole on Båtsfjordfjellet, Varanger Peninsula, revealed a succession of very low-grade, metasedimentary rocks which are assigned to specific Neoproterozoic formations recognisable ... -
Geology of the Fosen Peninsula and Trondheimsfjord Region: a synopsis and excursion guide.
Roberts, David (NGU-Rapport (98.119), Report, 1998)In the first part of the report, a synopsis is presented of the general geology and tectonostratigraphy of this part of Central Norway, with a slightly more detailed account given of the geology of Fosen Peninsula. The ... -
Grong. Berggrunnsgeologisk kart Grong M 1:250 000; trykt i farger
Roberts, David (Map, 1997)Beskrivelsen finnes på kartet. -
HeatBar Final Report 2010, Basement Heat Generation and Heat Flow in the western Barents Sea - importance for hydrocarbon systems
Balling, Niels; Willemoes-Wissing, Bjørn; Slagstad, Trond; Roberts, David; Mesli, Melani; Elvebakk, Harald; Ebbing, Jörg; Davidsen, Børre; Barrère, Cécile; Pascal, Christophe (NGU-Rapport (2010.030), Report, 2011)The HeatBar project aimed to determine the relative proportion of heat originating in the basement of the western Barents Sea and, as such, followed the methodologies and scientific approach developed in the course of the ... -
HeatBar Report 2008, basement heat generation and heat flow in the western Barents Sea - Importance for hydrocarbon systems
Elvebakk, Harald; Wissing, Bjørn; Slagstad, Trond; Skilbrei, Jan Reidar; Siedlecka, Anna; Roberts, David; Olesen, Odleiv; Gernigon, Laurent; Pascal, Christophe; Barrière, Cécile; Davidsen, Børre; Ebbing, Jörg (NGU-Rapport (2008.072), Report, 2008)The HeatBar project aims to determine the relative proportion of heat originating in the basement of the western Barents Sea and, as such, follows the methodologies and scientific approach developed in the course of 2005-2008 ... -
Hovedtrekk av geologien i Nord-Trøndelag og Fosenhalvøya.
Roberts, David (NGU-Rapport (85.274), Report, 1985)Rapporten er først og fremst en syntese av berggrunnsgeologien i Nord-Trøndelag og nabo-områdene i Sør-Trøndelag på Fosenhalvøya. Korte beskrivelser er gitt over de geologiske hovedinndelingene, med en noe mer omfattende ... -
Inferred Mesozoic faulting in Finnmark: current status and offshore links
Roberts, David; Lippard, Stephen J. (NGU Bulletin (443), Journal article, 2005)An earlier compilation of the post-Caledonian fault system in the Caledonian domain of Finnmark is reassessed in thelight of more recent diverse data acquired from a combination of general geology onshore, well data and ... -
Late Vendian U-Pb zircon age of a dolerite dyke from near Hamningberg, Varanger Peninsula - a preliminary report
Roberts, David; Walker, N. (NGU-Rapport (96.162), Report, 1996)A dolerite dyke cutting very low-grade metasandstones of the Løkvikfjellet group near Hamningsberg, NE Varanger Peninsula, has yielded a U-Pb zircon age (upper intercept) of 554+20\/-14 Ma; and a lower intercept of c.375 ...