Norsk versjon
	THE NATURAL STONE DATABASE
	Deposit Area 1833 - 609
	(Last updated 25.apr.2013)

Importance

Public:

Little Importance (reg. 18.02.2015)

Economical:

Minor interest , (Confirmed 18.okt.2012 by Leif Furuhaug)

Products

Commercial Name

Product description

	Trondhjemitt	Classification :	Colour :
		Play of colours :	Uniformity :
		Lithology :	Grain size :

Photo no. 1 showing Bergflate"

Deposit rock

	Lithology:		Weathering colour:
	Era:		Period:
	Dating:		Method:
	Genesis:		Form:
	Main texture:

Main grain size:

Main alteration:

	Strike/Dip:		Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Period:

	Province:
	Geotec.unit:
	Tectonic complex:
	Igneous complex:

Group:

Formation:

Information(s) in free text format

Description

Åsryggen vest for den gamle jernbanetraseen består av trondhjemitt (Søvegjarto et al. 1989). Det er denne bergarten som intruderer de kaledonske glimmerskifrene som er brukt til murestein. Trondhjemitten har benkning og har dels utviklet linjasjon. Steinen ble brukt i brukonstruksjoner og stikkrenner under skinnegangen, og til oppredningsverket i Guldsmedvik (Oxaal 1919). Lokaliteten har en gunstig beliggenhet like ved jernbanen, men brua over Ranaelva tåler ikke tungtransport av stein. Det finnes derfor i området bedre lokaliteter for å ta ut murestein av samme typen. Trondhjemitten er ikke testet som bygningstein til plater, men den vil som blokkstein være en lavprisstein. Mineralogi Hovedmineralet i bergarten er feltspatt. I underordnet mengde finnes også litt kvarts og glimmer, hovedsakelig muskovitt.

Historic

Stein fra bruddet ble tatt i store mengder i forbindelse med byggingen av den engelske jernbanen fra Mo til Storforshei som var ferdig i 1904. Det er sannsynligvis tatt stein fra skjæringen i forbindelse med den senere byggingen av Nordlandsbanen.

Location

Forekomsten ligger på østsiden av Ranaelva ved et gammelt sidespor til jernbanen ved Medforsen. Skinngangen er fjernet. Enklest adkomst er å kjøre til østsiden av Ranaelva ved Røssvoll. Etter brua over elva og dagens jernbanespor tar en sørover langs elva mot Plurheia. Etter ca. 1 km langs denne veien er det parkering for elvefiskere med sti ned mot elva. Ved å følge denne og den gamle jernbanetraseen mot sør kommer en til bruddet.

Photo(s) from the Deposit area:

Photo no. 1 showing Vegg i bruddet"

Bibliography:

From NGU's Reference Archive:

Oxaal, John , 1919

	Dunderlandsdalen. Fjeldbygningen inden gradavdelingskartet Dunderlandsdalens omraade

;Norges geologiske undersøkelse;KARTBESKRIVELSE; BOK;NGU; No.86;82 pages

Abstract:

This paper is a geological description of the Dunderland district in Nordland, a part of Northern Norway. The map accompanying the paper is a part of the official series of maps on the scale of 1:100 000, which is being published covering all Norway. The present map is the first in this series which has been published as a geological map. The author has in a previous paper divided Nordland into three regions: the granite region of the coast-zone (kystsonens granittregion) running parallel with coast-line and including larg masses of igneous rocks, principally granites. To the East of this region the inner region of schists (Den indre skiferregion or dalstrøkenes skiferregion) where sedimentary rocks as schists and limestone are predominant constituents. And thirdly, to the West of the granite region a similar zone of sedimentary rocks, the "skjærgaardens" region of schists (Skjærgaardens skiferregion). Dunderlandsdalen belong to the inner region of schists. Various types of mica schists are the ruling types of rocks within the area described. These rocks have sometimes the character of phyllitic schists, usually, however they are, more ordinary mica-schists very often with an abundance of garnets. Cyanite or disthene has been found in some cases as an accessory mineral.

Holmsen, Gunnar , 1932

	Rana. Beskrivelse til det geologiske generalkart.

;Norges geologiske undersøkelse;KARTBESKRIVELSE; TIDSSKRIFTARTIKKEL;NGU; No.136;1-107 + k pages

Abstract:

The present book forms a continuation of earlier appeared geological descriptions of the general maps Vega, Træna, Hatfjelldal and Salta all on a scale of 1:250 000. The general map Rana borders to the east to Sweden and to the north, south and west to the previous mentioned maps. The geological series of this map are the same as those found on the adjoining maps. They consist of palaeozoic sediments, and between the beds as well as on the surface volcanic rocks belonging to the epochs of the Norwegian Caledonian mountain chain folding, have been pressed out. The originally flat lying beds are folded and turned on end, and during these alterations the minerals of the original sediments are metamorphosed. Archaean rocks are nowhere exposed. The series of rocks here in question are called the North-Norwegian mica-schist series, and contain stratified rocks, schists, limestones and gneisses, as well as igneous rocks such as gabbro and granite. A view on the geological map will show that igneous rocks frequently occur along the Swedish frontier. In the middle of the country sedimentary rocks, mica-schists and limestones, however predominate. The geological structure is well demonstrated by the limestone beds.

Søvegjarto, U.; Marker, M.; Gjelle, S. , 1989

	Storforshei. Berggrunnskart; Storforshei; 20274; 1:50 000; trykt i farger;

;Norges geologiske undersøkelse;KART

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The fact sheet was created on 22.11.2024

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