Norsk versjon
	THE ORE DATABASE
	Deposit Area 1739 - 022
	(Last updated 16.feb.2005)

Importance

Public:

Little Importance (reg. 18.02.2015)

Economical:

Minor interest , (Confirmed 16.feb.2005 by Agnes Raaness)

Operations

	From - To	Activity	Comments
	1994 - 1994	Inspection	Company/Institution :NGU

Mineralization

	Era:	Paleozoic	Period:	Ordovician
	Dating:		Method:
	Genesis:	Volcex	Form:	Layer
	Main texture:	Banded	Min. distribution:	Massive (>50 % ore minerals)

Main grain size:

Fine grained (< 1 mm)

Main alteration:

	Strike/Dip:		Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Paleozoic

Period:

Ordovician

	Province:	Caledonides
	Geotec.unit:	Køli Nappe Complex
	Tectonic complex:	Gjersvik Nappe
	Igneous complex:	Skorovass Complex

Group:

Gjervik

Formation:

Mineralogy

	Relationship	Mineral	Amount
	Gangue mineral	Quartz	Major mineral (>10%)
	Ore mineral	Magnetite	Major mineral (>10%)
	Ore mineral	Pyrite	Subordinate mineral (1-10%)

Lithology:

	Relationship	Rock	Origin
	Wall rock	Grønnstein	Extrusive Original rock :Basalt
			Metamorphic facies :Greenschist

Information(s) in free text format

Free text

Forekomstene ligger langs en trang dal på sørsida av Mariafjellet. Kun mindre arbeider er gjort i området. Mineraliseringene består av båndete jernmalmer, som er opptil 30 cm mektige, i grønnstein. Noen cm brede bånd med massiv magnetitt veksler med finkornet kvarts og Mn-førende granat. Få idiomorfe pyritt-korn opptrer spredt i og langs kanten av BIF-sonene. Den massive jernmalmen er i kontakt med opptil 1 m mektige magnetittførende kvartsitt (blåkvartsitt). En rekke lignende BIF horisonter, opptil 1.5 m mektige, i Mariafjell-området er beskrevet av Oftedahl. De kan lettest studeres sørvest for fjellet, fra Tunnsjøen og oppover langs Brennbergbekken.

Bibliography:

From NGU's Reference Archive:

Oftedahl, Christoffer , 1958

	Oversikt over Grongfeltets skjerp og malmforekomster.

;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.202;1-75 + fo pages

Abstract:

Ore occurences of the Grong area: In the period 1910-1918 a great number of ore occurences were discovered in the Grong area. The late state geologist Steinar Foslie mapped the area in the years 1922-1931. Foslie also mapped all claims and occurences and made special field investigations in a few cases. This book presents a survey of all occurences chiefly based on the field observations of Foslie. In addition the present author has done some field work in connection with the three large deposits, Joma, Skorovass, and Gjersvik. The map, Plate 1, shows the areal geology and the location of the occurrences, numbered from 1 to 131. the ore of the occurrences is chiefly pyrite. The larger occurrences also contain some chalcopyrite and sphalerite etc. and the smaller occurrences contain ither pure pyrite with some magnetite. The Joma deposit (No. 1), contains about 15.5 mill. tons of ore. The ore zone forms an arc and is situated within a thick series of greenstones (Fig. 1). The Skorovass mine (No. 2), contains about 7,5 mill. tons of ore. The deposit is situated in a greenstone complex (Fig. 7), and is immediately surrounded by asid tuffs of quartz keratophyric composition (Table 1).

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	JS94190	Bedrock	Sampler :Sandstad, J.S./...Stored :Løkken Comment :BIF, magnetite and chert bands, few py grains No. of registrated element analyses = 1
	1183	Bedrock	No. of registrated element analyses = 1
	1184	Bedrock	No. of registrated element analyses = 1
	1185	Bedrock	No. of registrated element analyses = 1
	1186	Bedrock	No. of registrated element analyses = 1
	1187	Bedrock	No. of registrated element analyses = 1

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

Name of Locality : Skjerp 1

(Object Id : 1739,022,01,00)

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Location

County :

Nord-Trøndelag (17)

Municipality :

Røyrvik (1739)

Map 1:50000:

Røyrvik (1924-4)

Map 1:250000:

Grong

Marking point:

Longitude:

13.5131410

Latitude:

64.7679090

EU89-UTM Zone 33

(Coordinates IS confirmed)

X-coord:

429281 m.

Y-coord:

7183419 m.

Commodity

	Main Type:	Ferrous metals(Fe, Mn, Ti)	Sub Type:	Iron
			Element(s):	Fe

Production

	Activity:	Pitting	Reserves:
	Prod. method:		Production:
	Prod. status:		Volume of dump:

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	JS94188	Bedrock	Sampler :Sandstad, J.S./...Stored :Løkken Comment :BIF, massive magnetite, quartz lenses, few py grains No. of registrated element analyses = 1

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

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Analyse Results

from

Deposit Area 1739 - 022 Mariafjellet

Element analyses

( *=parts pr. million, #=parts pr.billion, Negative values means below detection limit value.)

Sample No.	Sample Type	Cu*	Zn*	Pb*	Co*	Ni*	Ag*	Au#
JS94188	Bedrock	30	57	-2	6	12	.2	-1.0
JS94190	Bedrock	13	32	-2	10	11	.4	-1.0
1183	Bedrock	121	176	137	3	27	1.2	41.0
1184	Bedrock	220	59	81	3	24	2.0	128.0
1185	Bedrock	112	117	151	1	27	1.8	122.0
1186	Bedrock	118	15285	16	14	18	1.0	38.0
1187	Bedrock	836	932	8	5	13	1.0	32.0

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Sample No.	Pt#	Pd#	As*	Cd*	Ba*	Mo*	Sn*	Sb*	Bi*
JS94188	-5.0	1.0	9	-1.0	21	2.00	-20	-5	11
JS94190	-5.0	-1.0	25	-1.0	27	2.00	-20	-5	6
1183	2.0	6.0	27	.8	8	1.00		2	3
1184	3.0	8.0	20	.2	6	3.00		2	2
1185	14.0	20.0	15	.2	5	5.00		2	3
1186	2.0	3.0	16	60.7	5	6.00		2	2
1187	1.0	2.0	14	4.2	6	9.00		2	2

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Sample No.	S%	V*	Cr*	Mn*	Fe%	Th*	U*	W*	Sr*
JS94188	.27	90	152	938	9.03			-20	22.0
JS94190	.63	38	215	3556	7.72			-20	20.0
1183	28.51	49	12	248	26.55	3.00	5.00	1	11.0
1184	40.12	31	6	17	26.07	3.00	5.00	1	1.0
1185	35.63	97	3	63	29.42	3.00	5.00	1	1.0
1186	29.81	69	5	63	23.98	2.00	5.00	3	1.0
1187	16.78	4	2	6	14.60	1.00	5.00	2	1.0

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Sample No.	Y*	La*	B*	Te*
JS94188	7.0	-1.00		-10.00
JS94190	2.0	-1.00		-10.00
1183		4.00	2
1184		2.00	2
1185		2.00	2
1186		2.00	2
1187		2.00	3

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The fact sheet was created on 19.05.2024

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

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