Norsk versjon
	THE INDUSTRIAL MINERAL DATABASE
	Deposit 1578 - 305 Onilsavatn
	(Object Id: 7869) (Last updated: 28.10.2020)

Operations

	From - To	Activity	Comments
	1970	Test mining	Company/Institution :Folldal verk
			Test mining with a 50 m long tunnel

Mineralization

	Era:	Proterozoic	Period:
	Genesis:	Metamorphic formation	Form:	Lens
	Main texture:	Granoblastic	Min. distribution:	Massive (>50 % ore minerals)

Main grain size:

Medium grained (1-3 mm)

	Strike/Dip:		Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Proterozoic

Period:

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

Group:

Formation:

Mineralogy

	Mineral	Amount
	Olivine	Major mineral (>90%)

Information(s) in free text format

Free text

Forekomsten ligger rett vest for Onilsavatn i Tafjord. Størrelsen er anslått til å være 600 x1100 meter. Det var prøvedrift på forekomsten i perioden 1971-1974 av Folldal verk. Da ble det drevet inn flere stoller, hvorav den lengste var på 70 meter. Under denne perioden ble det boret 15 kjernehull. Ny drift på forekomsten forsøkes startet opp av gruveselskapet Novemco i 2000. Dette har imidlertid ikke resultert i noen permanent drfit. Forekomsten er imidlertid av meget god kvalitet, med høyt MgO og lavt LOI i bergarten. Driften ble etter kort til lagt i driftshvile. Det er svært mye rasmateriale fra fjellksred som består av dunitt. NGU har utført refraksjonssiemikk og resultatene viser at rasviften har en tonnasje på 25 millioner tonn med lett brytbar dunitt.

Bibliography:

From NGU's Reference Archive:

Brueckner, H.K. , 1977

	A structural, stratigraphic and petrologic study of anorthosites, eclogites and ultramafic rocks and their country rocks, Tafjord area, western South Norway.

;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.332;1-53 + pl pages

Abstract:

The Tafjord area of the central basal gneiss region contains Caledonized metamorphic rocks divided into two groups. The 1000 m.y. old Fetvatn Geniss is a homogeneous zone of granodioritic gneiss that was intruded as part of a large plutonic complex during the Sveconorwegian Cycle. The heterogeneous Vikvatn Sequence contains obvious metasedimentary and metavolcanic rocks and is comprised of the Øyen, Øvste Rødal and Svartegga groups. In addition, anothosite, eclogite and anhydrous peridotite occur within the Øyen and Øvste Rødal groups. The quartizite-rich Svartegga group may form the basal (Eocambrian) part of the Caledonian supracrustal sequence typical of the eastern basal gneiss region. The Øyen and Øvste Rødal groups would then be Precambrian metasedimentary sequences seperated from the Svartegga group by a major unconformity. Structures include two early generations (F1A og F1B) of east-plunging, reclined, isoclinal, similar folds. Later (F2) folds generally have a concentric geometry, disharmonic profiles and variable axes. The F1 and F2 fabrics are identical to stuctures in the eastern basal geniss region that are believed to have formed during the Caledonian orogeny; but the F1A fabric may be a heterogeneous assemblage of Precambrian structures that were homogenized (Caledonized) during the intense F1B deformation.

Mauring, Eirik; Tønnesen, Jan Fredrik , 1998

	Refraksjonsseismiske målinger ved kartlegging av olivinforekomst i Tafjord, Møre og Romsdal

;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.98.093;14 pages

Abstract:

Refraksjonsseismiske målinger er utført langs tre profiler ved Tafjord, Møre og Romsdal. Undersøkelsen er en oppfølging av tidligere utførte refraksjons- seismiske målinger (Mauring et al. 1997). Hensikten med målingene var å kartlegge løsmassemektighet nær olivinforekomst, samt forekomstens forløp under løsmassene. Tolkning av to av profilene (P7 og P9) indikerer lokale høyhastighetssoner i fjell i en bredde på ca. 50 m. Hastigheten er større enn 7000 m/s og kan indikere massiv olivinbergart. Dyp til fjell er i størrelsesorden 20-30 m ved profilene. De refraksjonsseismiske målingene indikerer to eller tre hastighetslag i løs- masser. Avsetningene representerer trolig tørre skredavsetninger i øvre deler. Mot dypet kan avsetningene være dominert av tørre/vannmettede skredavsetninger eller morene.

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	HGNGU_96564	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	HGNGU_96565	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	HGNGU_96566	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	HGNGU_96567	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	HGNGU_96568	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97001	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97002	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97003	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97004	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97005	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97006	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97007	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97008	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97009	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97010	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97011	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97012	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97013	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97014	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97015	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97016	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1
	NGUHJ97017	Bedrock	Comment: This is a dummy sample that does not excists. The assosciated analyses have been compiled from various published and unpublished reports No. of registrated oxide analyses = 1

NB! All analyse values are shown at the end of the printout.:

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Analyse Results

from

Deposit Area 1578 - 305 Onilsavatn

Oxide analyses

( All values are in % )

Sample No.	Sample Type	SiO2	Al2O3	TiO2	Fe2O3	MnO	MgO	CaO
HGNGU_96564	Bedrock	41.20	1.12	0.00	8.90	0.11	46.60	0.63
HGNGU_96565	Bedrock	42.80	2.01	0.00	8.50	0.12	42.40	1.77
HGNGU_96566	Bedrock	42.60	1.52	0.00	8.10	0.11	45.00	1.25
HGNGU_96567	Bedrock	42.40	0.99	0.00	8.80	0.12	45.20	0.69
HGNGU_96568	Bedrock	42.70	0.65	0.00	8.70	0.12	45.60	0.50
NGUHJ97001	Bedrock	41.40	0.51	0.00	7.40	0.10	47.70	0.15
NGUHJ97002	Bedrock	42.30	1.02	0.00	7.70	0.10	47.30	0.81
NGUHJ97003	Bedrock	42.70	0.50	0.00	7.10	0.09	49.10	0.21
NGUHJ97004	Bedrock	41.60	0.61	0.00	7.60	0.10	49.30	0.22
NGUHJ97005	Bedrock	41.50	0.39	0.00	7.73	0.10	49.00	0.48
NGUHJ97006	Bedrock	41.80	0.81	0.00	7.40	0.10	48.80	0.30
NGUHJ97007	Bedrock	41.80	1.00	0.00	8.30	0.11	47.30	0.81
NGUHJ97008	Bedrock	41.20	0.40	0.00	8.10	0.10	49.20	0.41
NGUHJ97009	Bedrock	41.50	0.41	0.00	8.40	0.10	49.30	0.17
NGUHJ97010	Bedrock	41.40	0.29	0.00	6.70	0.08	50.00	0.10
NGUHJ97011	Bedrock	41.90	0.53	0.00	7.80	0.10	49.10	0.16
NGUHJ97012	Bedrock	42.80	0.36	0.00	7.60	0.08	48.50	0.36
NGUHJ97013	Bedrock	41.90	0.15	0.00	7.20	0.08	50.10	0.06
NGUHJ97014	Bedrock	43.00	0.49	0.00	6.80	0.08	48.10	0.74
NGUHJ97015	Bedrock	42.60	0.51	0.00	7.30	0.09	48.50	0.48
NGUHJ97016	Bedrock	41.90	0.53	0.00	7.70	0.10	48.90	0.25
NGUHJ97017	Bedrock	43.30	0.45	0.00	6.80	0.09	48.10	0.06

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

Sample No.	Na2O	K2O	P2O5	Loss	Sum
HGNGU_96564	0.05	0.02	0.00	1.43	100.00
HGNGU_96565	0.10	0.01	0.00	2.40	100.00
HGNGU_96566	0.06	0.01	0.00	1.12	100.00
HGNGU_96567	0.06	0.01	0.00	1.28	100.00
HGNGU_96568	0.02	0.01	0.00	1.51	100.00
NGUHJ97001	0.00	0.01	0.00	2.26	100.00
NGUHJ97002	0.01	0.04	0.00	0.68	100.00
NGUHJ97003	0.00	0.00	0.00	0.32	100.00
NGUHJ97004	0.00	0.01	0.00	0.46	100.00
NGUHJ97005	0.01	0.01	0.00	0.86	100.00
NGUHJ97006	0.00	0.01	0.00	0.66	100.00
NGUHJ97007	0.01	0.01	0.00	0.62	100.00
NGUHJ97008	0.00	0.01	0.00	0.46	100.00
NGUHJ97009	0.00	0.01	0.00	0.26	100.00
NGUHJ97010	0.00	0.00	0.00	1.18	100.00
NGUHJ97011	0.00	0.00	0.00	0.40	100.00
NGUHJ97012	0.00	0.01	0.00	0.26	100.00
NGUHJ97013	0.00	0.00	0.00	0.42	100.00
NGUHJ97014	0.01	0.01	0.00	0.32	100.00
NGUHJ97015	0.00	0.01	0.00	0.36	100.00
NGUHJ97016	0.00	0.00	0.00	0.32	100.00
NGUHJ97017	0.00	0.00	0.00	1.00	100.00

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The fact sheet was created on 25.04.2024

Questions or comments regarding the fact sheet can be emailed to: ressursdatabaser@ngu.no

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