Norsk versjon
	THE ORE DATABASE
	Deposit Area 1742 - 004
	(Last updated 15.mai.2006)

Importance

Public:

Little Importance (reg. 18.02.2015)

Economical:

Minor interest

Operations

	From - To	Activity	Comments
	1970 - 1970	Geology	Company/Institution :NGU
	1980 - 1980	Geology	Company/Institution :Grong Gruber A/S
	1980 - 1980	Geophysics	Company/Institution :Grong Gruber A/S
	1996 - 1996	Sampling	Company/Institution :NGU

Mineralization

	Era:	Paleozoic	Period:	Ordovician
	Dating:		Method:
	Genesis:	Volcex	Form:	Layer
	Main texture:	Banded	Min. distribution:	Semi-massive (20-50 % ore minerals)

Main grain size:

Fine grained (< 1 mm)

Main alteration:

No country rock alteration

	Strike/Dip:	236 / 60	Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Paleozoic

Period:

Ordovician

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

Group:

Gjersvik

Formation:

Mineralogy

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

Lithology:

	Relationship	Rock	Origin
	Host rock	Garbenschist	Sedimentary Original rock :Tuffite
			Metamorphic facies :Greenschist
	Wall rock	Greenschist	Sedimentary Original rock :Tuffite
			Metamorphic facies :Greenschist

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Host rock	Foliation	Strike/Dip :236 / 60	Post-mineralisation ;...Effect :Modifies
	Host rock	Schistosity	Strike/Dip :250 / 75	Post-mineralisation ;...Effect :Modifies

Information(s) in free text format

Free text

Mineraliseringen er blottet ved en bekk 400 m og 200 m vestsørvest for Angeltjønnin, og kan nåes fra skogsbilvei fra Stortjønna i sør. Det er skutt litt i en 70 cm høy skjæring på nordsida av bekken. Smale (1-15 mm) semimassive bånd med svovelkis opptrer i et 50-60 cm tykt lag i hornblendeskifer med utvikla garbentekstur. I den mineraliserte sonen finnes også linser med magnetitt og chert og felsiske begarter. Basemetallinnholdet er lavt i denne sonen. Mineraliseringen er antatt å opptre på et lavere stratigrafisk nivå enn forekomstene Godejord og Finnbu, innen den grønnsteinsdominerte delen av Limingengruppen. 100 m sør for Angeltjønnin er det påvist en ny svak leder som Grong Gruber A/S røsket på i 1980 (Angeltjern sør). Kvartsførende svovelkisrike bånd (10-25 mm) i hornblendeskifer ble påvist. Strøkretningen til mineraliseringen er 252/70. Analyser viser 0,99 % og 1,40 % Cu med mindre enn 0,1 % Pb og Zn (Olesen 1980). Denne røsk er gjenrast og mineraliseringen ble ikke påvist ved befaring i 1996.

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).

Olesen, Odleiv , 1980

	Oppfølging av områder med malmpotensial i Grongfeltet.

;NTH Bergavd.;AVHANDLING

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	NT0163.01	Bedrock	Sampler :Sandstad, J.S./...Size(kg) :2 Comment :Pyrite-bands (2-10mm), fine grained, in dark green hornblende schist with felsic lenses No. of registrated element analyses = 1
	1155	Bedrock	No. of registrated element analyses = 1
	1156	Bedrock	No. of registrated element analyses = 1
	1157	Bedrock	No. of registrated element analyses = 1
	1158	Bedrock	No. of registrated element analyses = 1
	1159	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 : 1742,004,01,00)

---

Location

County :

Nord-Trøndelag (17)

Municipality :

Grong (1742)

Map 1:50000:

Grong (1823-4)

Map 1:250000:

Grong

Marking point:

Longitude:

12.5931930

Latitude:

64.4644020

EU89-UTM Zone 33

(Coordinates IS confirmed)

X-coord:

384256 m.

Y-coord:

7150959 m.

Commodity

	Main Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Sub Type:	Sulphides
			Element(s):	Kis

Production

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

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	NT0163.02	Bedrock	Sampler :Sandstad, J.S./...Size(kg) :2 Comment :Pyrite-bands (5-10mm), semi-massive in garben schist with felsic and fine grained magnetite lenses No. of registrated element analyses = 1

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

Name of Locality : Angeltjern sør

(Object Id : 1742,004,02,00)

---

Location

County :

Nord-Trøndelag (17)

Municipality :

Grong (1742)

Map 1:50000:

Grong (1823-4)

Map 1:250000:

Grong

Marking point:

Longitude:

12.6045610

Latitude:

64.4640490

EU89-UTM Zone 33

(Coordinates IS confirmed)

X-coord:

384801 m.

Y-coord:

7150899 m.

Commodity

	Main Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Sub Type:	Sulphides
			Element(s):	Kis

Production

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

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	JS96011	Bedrock	Sampler :Sandstad, J.S./...Stored :Løkken Comment :Sulphide veinlets, py+sl+cpy, in silicified greenstone No. of registrated element analyses = 1

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

---

Analyse Results

from

Deposit Area 1742 - 004 Angeltjernhøgda

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#
JS96011	Bedrock	920	9621	19	53	39	.8	22.0
NT0163.01	Bedrock	14	96	-3	153	17	-.3	10.0
NT0163.02	Bedrock	113	53	5	217	121	-.3	18.0
1155	Bedrock	84	306	7	71	4	.3	13.0
1156	Bedrock	34	22	2	152	4	.3	13.0
1157	Bedrock	71	27	2	110	5	.3	9.0
1158	Bedrock	107	35	2	111	3	.3	9.0
1159	Bedrock	54	38	3	79	5	.3	14.0

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

Sample No.	Pt#	Pd#	Rh#	As*	Cd*	Ba*	Mo*	Sb*	Bi*
JS96011	1.0	3.0	3.0	9	54.2	4	4.00	-2	-2
NT0163.01	-1.0	3.0	3.0	10	1.2	4	25.00	-2	-2
NT0163.02	-1.0	-1.0	-1.0	18	1.0	28	44.00	-2	-2
1155	1.0	2.0		28	.2	2	19.00	2	4
1156	2.0	2.0		20	.2	2	58.00	2	8
1157	1.0	2.0		33	.4	2	37.00	2	6
1158	3.0	2.0		35	.2	2	21.00	2	3
1159	1.0	2.0		31	.2	2	46.00	2	5

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

Sample No.	S%	V*	Cr*	Mn*	Fe%	Th*	U*	W*	Sr*
JS96011	.78	45	61	4562	3.77	7.00	-5.00	-2	91.0
NT0163.01	3.33	198	41	610	16.03	-2.00	-5.00	-2	12.0
NT0163.02	5.27	303	192	1949	24.34	-2.00	-5.00	2	5.0
1155	35.72	2	1	29	20.85	2.00	5.00	1	1.0
1156	35.08	48	2	109	23.38	2.00	7.00	1	1.0
1157	39.37	22	3	157	21.36	2.00	5.00	1	1.0
1158	33.41	13	1	98	21.15	2.00	5.00	1	1.0
1159	34.37	17	4	164	21.99	2.00	5.00	1	2.0

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

Sample No.	La*	B*
JS96011	-1.00	-3
NT0163.01	1.00	-3
NT0163.02	3.00	5
1155	2.00	2
1156	2.00	2
1157	2.00	2
1158	2.00	2
1159	2.00	2

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The fact sheet was created on 16.01.2025

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

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