Norsk versjon
	THE NATURAL STONE DATABASE
	Deposit 3101 - 612 Brekke
	(Object Id: 9831) (Last updated: 08.07.2021)

Products

Commercial Name

Product description

	Iddefjord granitt	Classification: Massive blocks	Colour: Grayish
		Play of colours :	Uniformity: Good
		Lithology: Granite	Grain size: Fine - medium grained (<1mm - 3 mm)

Mineralogy:

		Quartz	Major mineral (>10%)
		Plagioclase	Major mineral (>10%)
		Microcline	Major mineral (>10%)
		Biotite	Subordinate mineral (1-10%)
		Opaque	Accessory mineral (<1%)
		Titanite	Accessory mineral (<1%)
		Zircon	Accessory mineral (<1%)
		Hornblende	Accessory mineral (<1%)
		Chlorite	Accessory mineral (<1%)
		Apatite	Accessory mineral (<1%)
		Muscovite	Accessory mineral (<1%)

Photo no. 1 showing Polert plate" Photo no. 2 showing Polert plate"

Operations

	From - To	Activity	Comments
	1860	Regular production	Company/Institution :Diverse drivere
			Stort sett sammenhengende drift i hele perioden.

Deposit rock

	Lithology:		Weathering colour:
	Era:	Proterozoic	Period:
	Dating:	918 (-7\+7) million year	Method:	Rb/Sr
	Genesis:	Magmatic	Form:	Massive
	Main texture:	Structureless

Main grain size:

Main alteration:

	Strike/Dip:		Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Proterozoic

Period:

	Province:	East Norwegian Basement Province
	Geotec.unit:
	Tectonic complex:
	Igneous complex:	Iddefjord Batholith

Group:

Formation:

Information(s) in free text format

Description

Forekomsten har vært drevet i større skala fra slutten av 1800-tallet. I sydlige del ligger et granittbrudd som drives aktivt i dag. Nordover fra dette er småkollet terreng, lite utbygget. Forekomsten er nærmere 3 km lang og rundt 1 km bred. Benkning og sprekketetthet varierer noe, men i store deler av området ligger benkeavstanden over 1,5 meter og avstanden mellom steile sprekker mer enn 2 meter. Granitten er vesentlig middelskornet, grå til rødlig på farge. Reservegrunnlaget antas å være stort.

Location

Dette området ligger ca. 2 km nord-øst for den innerste delen av Iddefjorden.

Photo(s) from the Deposit area:

Photo no. 1 showing Panoramabilde av bruddet"

Bibliography:

From NGU's Reference Archive:

Gautneb, Håvard ; Øvereng, Odd ; Heldal, Tom , 1999

	Granittforekomster i Halden kommune.

;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.99.061;17 pages

Abstract:

Rapporten gir en oversikt over de industrielle aspekter ved natursteinsdrift og variasjonen i Iddefjordsgranitten med hensyn til dens potensiale som naturstein. Ved Iddefjorden har granitten en lengde og bredde på henholdsvis ca. 20 og 4 km. Fra polerte prøveplater har vi delt granitten inn i følgende typer: Type A er middelskornet og noe rødlig i farge og har sin største utbredelse rundt brekke. Type B er middels til grovkornet og grå av farge og opptrer i området Hov-Folkvang-Skriverøya. Type C er lik type B men har en mindre kornstørrelse og finnes i området fra Berby og sørover. Type D er markert forskjellig fra alle andre og er finkornet og lys grå av farge, den finnes i området rundt Liholt. Basert på oppsprekking har vi delt inn granitten i følgende klasser: Klasse 1 (mest massiv) har mer enn 1.5 meter benketykkelse og 2-3 meter mellom vertikale sprekker. Klasse 3 (mest oppsprukket) har mindre enn 1.5 meter benketykkelse og 2-3 meter mellom vertikale sprekker. Granitt av klasse 2 finnes i en smal sone i Hovområdet samt ved Skriverøya; her er det mulig å finne forekomster med liten skrotprosent og stor blokk. Granitt av klasse 2 har ganske stor utbredelse, spesielt vil vi påpeke området nord for Brekke. Her er det mulig å finne forekomster som kan produsere stor blokk, men skrotprosenten vil nok bli høyere enn i området med klasse 1. I områder der granitten er av klasse 3 tror vi det er vanskelig å etablere lønnsom blokkproduksjon.

Pedersen, Svend; Maaløe, Sven , 1990

	The Iddefjord granite: geology and age

;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU Bulletin; No.417;55-64 pages

Abstract:

The Iddefjord granite forms part of the Swedish Bohus batholith and ranges in composition from diorite to granite. The granite consists of 13 individual plutons, and the mechanism of intrusion is related to block subsidence rather than forceful intrusion. There is no evidence of marginal chill, and the temperature of the host gneiss must have been similar to that of the granites. This suggests that the intrusion took place in a regionally pre-heated rock complex under plutonic conditions. The major element trends of the granites are similar to those of recent granite batholiths. Rb-Sr age determinations carried out on two of the granites yield a common isochron age of 918+- 7Ma with an initial Sr isotope ratio of 0.7063 +- 0.0008 suggesting contributions from older crustal components. Mineral analyses from one of the investigated granite samples indicate a Rb/Sr mineral age in the order of 835 Ma, reflec- ting either a slow cooling of the pluton or a younger thermal effect causing resetting of the mineral system.

Oxaal, John , 1916

	Norsk granit

;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.76;1-220 pages

Abstract:

This work is a report of granite and the granite industry in Norway. It contains a description of the various fields of granite and similar rocks from a scientific as well as from a technical and economical standpoint. The geological occurrence of the various rocks, their chemical and mineralogical composition, are thoruoughlyoughly treated, also the questions of practical interest, as the quality and other technical properties, further the problems of location and conditions for transport, conditions for quarrying and otherquestions of interest in the utilization of the various occurrences of granite. Granite: This chapter consideres first the mineralogical and chemical composition of the granite, and the various types of granite resulting from the varying composition; thereafter the most important structural types and how these are dependent on the geological appearance of the rock. Lakkolites and other froms assumed by granite masses when injected into the crust of the earth, are mentioned; some examples of beautifully formed lakkolites are also mentioned. The question of sheet structure and rift in the granite are of great importance in its utilization, and are of interest both practically and theoretically.

Name of Locality: Brekke

(Object Id: 14765 612,01,00)

Location

County:

Østfold

Municipality:

Halden (3101)

Map 1:50000:

Aspern (2013-3)

Map 1:250000:

Oslo

Coordinate system:

EU89-UTM Zone 32

East:

642453 m.

North:

6543104 m.

Longitude:

11.4801280

Latitude:

59.0036770

Show on map

Resource

	Resource Type:	Granite and other igneous rocks	Resource Subtype:	Granite
			Brickstone(Y/N):

Resources and production

	Activity:	Stone quarrying	Reserves:
	Operating method:	Open pit mining	Historical production:

Name of Locality: Brekke

(Object Id: 14766 612,02,00)

Location

County:

Østfold

Municipality:

Halden (3101)

Map 1:50000:

Aspern (2013-3)

Map 1:250000:

Oslo

Coordinate system:

EU89-UTM Zone 32

East:

642349 m.

North:

6543255 m.

Longitude:

11.4784330

Latitude:

59.0050580

Show on map

Resource

	Resource Type:	Granite and other igneous rocks	Resource Subtype:	Granite
			Brickstone(Y/N):

Resources and production

	Activity:	Stone quarrying	Reserves:
	Operating method:	Open pit mining	Historical production:

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	24360	Block	Stored: Løkken Comment: Granitt, Iddefjordstype

Name of Locality: Vestfjellet

(Object Id: 14767 612,03,00)

Location

County:

Østfold

Municipality:

Halden (3101)

Map 1:50000:

Aspern (2013-3)

Map 1:250000:

Oslo

Coordinate system:

EU89-UTM Zone 32

East:

642000 m.

North:

6543749 m.

Longitude:

11.4726650

Latitude:

59.0096150

Show on map

Resource

	Resource Type:	Granite and other igneous rocks	Resource Subtype:	Granite
			Brickstone(Y/N):

Resources and production

	Activity:	Stone quarrying	Reserves:
	Operating method:	Open pit mining	Historical production:

Name of Locality: Bakke

(Object Id: 14768 612,04,00)

Location

County:

Østfold

Municipality:

Halden (3101)

Map 1:50000:

Aspern (2013-3)

Map 1:250000:

Oslo

Coordinate system:

EU89-UTM Zone 32

(Coordinates NOT confirmed)

East:

641218 m.

North:

6544891 m.

Longitude:

11.4598070

Latitude:

59.0201190

Show on map

Resource

	Resource Type:	Granite and other igneous rocks	Resource Subtype:	Granite
			Brickstone(Y/N):

Resources and production

	Activity:	Stone quarrying	Reserves:
	Operating method:	Open pit mining	Historical production:

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The fact sheet was created on 19.04.2024

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