English version
	MALMDATABASEN
	Forekomstområde 1924 - 019
	(Sist oppdatert 07.mar.2017)

Betydning

Offentlig:

Liten betydning (reg. 02.06.2015)

Økonomisk:

Lite viktig , (Stadfestet 02.jun.2015 av Terje Bjerkgård)

Operasjoner

	Fra - Til	Aktivitet	Kommentar
	2011 - 2011	Geofysikk	Selskap/Institusjon:NGU
			Aerial survey (mag., EM, radiometry)
	2011 - 2013	Geologi	Selskap/Institusjon:NGU

Mineralisering

	Æra:	Proterozoikum	Periode:	Mesoproterosoikum
	Datering:		Metode:
	Genese:	Kjemisk sediment	Form:	Linse
	Hovedtextur:	Båndet	Min. fordeling:	Semi-massiv

Kornstørrelse:

Middelskornet (1-3 mm)

Hovedomvandling:

Ingen sidestensomvandling

	Strøk/Fall:		Retning:
			Feltstupning:

Stratigrafisk klassifikasjon av vertsbergart

Æra:

Proterozoikum

Periode:

Mesoproterosoikum

	Provins:	Troms-Finnmark grunnfjellsprovins
	Geotek.enhet:
	Tektonisk complex:	Mauken Tectoni Window
	Intrusivt komplex:

Gruppe:

Målselva Group

Formasjon:

Myrefjellet Formation

Mineralogi

	Relasjon	Mineral	Mengde
	Gangmineral	Karbonat	Hovedmineral (>10%)
	Gangmineral	Gruneritt	Hovedmineral (>10%)
	Gangmineral	Kvarts	Hovedmineral (>10%)
	Gangmineral	Biotitt	Underordnet mineral (1-10%)
	Gangmineral	Kloritt	Aksessorisk mineral (<1%)
	Malmmineral	Magnetitt	Hovedmineral (>10%)
	Malmmineral	Svovelkis	Aksessorisk mineral (<1%)

Litologi:

	Relasjon	Bergart	Opprinnelse
	Sidebergart	Grønnskifer/tuffitt	Sedimentær Opprinnelig bergart :Tuffitt
			Metamorf fase :Grønnskifer
	Sidebergart	Grønnstein	Ekstrusiv Opprinnelig bergart :Basalt
			Metamorf fase :Grønnskifer

Opplysning(er) i fritekstformat

Fri tekst

The iron formation is exposed in the pronounced Bjelma valley to the west of Myrefjellet. This valley (with the Bjelma stream), marks the boundary between the banded, tuffitic greenschist and the generally massive greenstone/ metabasalt. It gives a well-defined magnetic anomaly. The iron formation is located in the northwestern part of this valley, in the extension of a layer of calc-brecciated greenstone. It has a length of at least 700 m and a thickness of up to 30 m close to the major bend of the Bjelma stream. The iron formation varies in composition across strike, from quartz- to carbonate-rich. The carbonate is generally a brown, Fe-rich calcite or ankerite. Fine-grained magnetite is present in thin bands throughout the formation, generally the thin bands are found in zones less than one meter in thickness. Some zones in the formation are enriched in sulfides, mainly pyrite. One sample analyzed of the carbonate-rich part contains 25.5 % Fe2O3, 0.07 % TiO2 and 0.18 % P2O5, and one quartz-rich sample contains 33.0 % Fe2O3, 0.03 % TiO2 and 0.14 % P2O5. A 5-20 m thick layer of banded to laminated schist quite strongly enriched in magnetite is present in the banded greenschist some meters from the boundary to the greenstone. The unit contains bands with 2-4 % magnetite (measurements by handheld susceptibility meter. The unit can be followed for more than 1 km along strike. It is possible that this unit somehow is related to the iron formation.

Litteraturfortegnelser:

Fra NGU's Referansearkiv.:

Bjerkgård, Terje; Henderson, Iain; Sandstad, Jan Sverre; Schönenberger, Johannes; Slagstad, Trond , 2015

	Geology of the Mauken tectonic window, Målselv, Troms

;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.2015.013;60+kart sider

Abstrakt:

This report presents the results from bedrock mapping in the Mauken tectonic window, carried out in several periods in 2011-2013. During the NGU MINN program, the Mauken area has been subject to a high-resolution airborne geophysical survey (magnetometry, radiometry, EM), followed by bedrock mapping and structural geology investigations. The work in the Mauken area is part of a larger project in southern Troms, with the goal to work out a structural-tectonic-metallogenic model and interpretaion for the basement areas in the whole region.

Feltprøver

	Prøvenr.	Prøvetype	Diverse
	TBMA_5	Fastfjell	Prøvetaker :T. Bjerkgård/...Lager :Løkken Kommentar :Karbonatbåndet jernformasjon Antall registrerte elementanalyser = 1
	TBMA_72	Fastfjell	Prøvetaker :T. Bjerkgård/...Lager :Løkken Kommentar :Kvartsbåndet jernformasjon Antall registrerte elementanalyser = 1

NB! Alle analyseverdier er vist i slutten av utskriften.:

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Analyseresultater

fra

Forekomstområde 1924 - 019 Bjelma

Elementanalyser

( *=parts pr. million, #=parts pr.billion, Negative verdier betyr under deteksjonsgrensen.)

Prøvenr.	Prøvetype	Cu*	Zn*	Pb*	Co*	Ni*	Ag*	Au#
TBMA_5	Fastfjell	158	25	-3	30	27
TBMA_72	Fastfjell	337	8	2	12	18	.6	5.4

------------------

Prøvenr.	As*	Cd*	Ba*	Mo*	Sb*	Bi*	Se*	Ga*	Ge*
TBMA_5			126	3.00				2.00	2.00
TBMA_72	2	-1.0	31	-1.00	1	-1	-1.00	1.00

------------------

Prøvenr.	S%	V*	Cr*	Mn*	Fe%	Th*	U*	W*	Rb*
TBMA_5		44	45	9217	17.83	-4.00	-2.00	-5	3.0
TBMA_72	-.02	18	44	3330	23.06	-1.00	-1.00	2	4.0

------------------

Prøvenr.	Sr*	Y*	Zr*	Nb*	Ta*	Cs*	La*	Ce*	Pr*
TBMA_5	12.0	17.0	19	2.00	-4.00	-10.00	-20.00	90.00
TBMA_72	5.0	13.0	14	-1.00	-1.00	-1.00	9.00	21.00	2.00

------------------

Prøvenr.	Nd*	Sm*	Eu*	Gd*	Tb*	Dy*	Ho*	Er*	Tm*
TBMA_5	21.00	14.00
TBMA_72	9.00	2.00	-1.00	2.00	-1.00	2.00	-1.00	1.00	-1.00

------------------

Prøvenr.	Yb*	Lu*	Na*	Mg*	Al*	Si*	P*	K *	Ca*
TBMA_5	-5.00		371	15316	6827	######	790	1312	13508
TBMA_72	1.00	-1.00	37	3377	3493	######	611	249	3359

------------------

Prøvenr.	Sc*	Ti*	Hf*	Hg*
TBMA_5	5.00	396	-5.00
TBMA_72		180	-1.00	-1

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Faktaarket ble generert 19.05.2024

Spørsmål eller kommentarer vedrørende faktaarket kan mailes til: ressursdatabaser@ngu.no

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