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THE ORE DATABASE
Occurence 5043 - 059 Gjersviktangen
(Object Id: 353)
(Last updated: 03.12.1998)
Location
County: Trøndelag Municipality: Raarvihke (5043)
Map 1:50000: Røyrvik (1924-4) Map 1:250000: Grong
Coordinate system: EU89-UTM Zone 33
East: 425512 m. North: 7192888 m.
Longitude: 13.4289740 Latitude: 64.8520360
Show on map
Resource
Resource Type: Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) Resource Subtype: Sulphides
Element(s): Kis
Importance
Raw material meaning: Not Assessed (reg. 18.02.2015)

Resources and production
Activity: Exploration Reserves:
Operating method: Historical production:


Operations
From - To Activity Comments
1970 - 1970 Geochemistry Company/Institution :NGU
1970 - 1970 Geophysics Company/Institution :NGU
1991 - 1991 Sampling Company/Institution :NGU
1996 - 1996 Sampling Company/Institution :NGU

Mineralization
Era: Paleozoic Period: Ordovician
Genesis: Volcex Form: Irregular
Main texture: Vein network Min. distribution: Disseminated (<20 % ore minerals)
Main grain size: Fine grained (< 1 mm) Main alteration: Albitisation
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: Gjersvik Formation:

Mineralogy
Relationship Mineral Amount
Gangue mineral Amphibole Major mineral (>10%)
Gangue mineral Albite Major mineral (>10%)
Gangue mineral Chlorite Major mineral (>10%)
Ore mineral Pyrite Major mineral (>10%)

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

Structures
Location: Type: Orientation(360 gr.): Relation to min.:
Host rock Foliation Strike/Dip :210 / 20 Post-mineralisation ;...Effect :Modifies

Information(s) in free text format
Free text
Mineraliseringen finnes på sørsiden av Gjersvikbukta, sørsørvest for Gjersvikforekomsten. Den er godt blottet langs vannkanten, spesielt ved lav vannstand i Limingen. Skjerp som er beskrevet av Oftedahl (1958) er ikke senere påvist i dette området. Mørk grønnstein, dels med putestruktur lengst nord på tangen, dominerer i området. En rekke mindre rustsoner med svovelkis på årer/stikk og disseminert finnes i denne grønnsteinen. Grønnsteinen er dels noe bleket p.g.a. omvandling. Basemetallinnholdet i sulfidmineraliseringen er ubetydelig. Grong Gruber antar at hvis nivået til Gjersvikmalmen finnes sør for Limingen må det ligge lengre øst enn denne lokaliteten.

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).

Logn, Ø. , 1973
Geologiske, geofysiske og geokjemiske undersøkelser Grongfeltet/Grongprojektet.
;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.974
Abstract:
Objekt 48: Sandtjern skjerp Objekt 49: Skiftesmyra skjerp Objekt 50: Stordalen-anomaliene

Fieldsamples
Sample No. Sample type Miscellanrous
JS96029 Bedrock
Sampler: Sandstad, J.S./...Stored: Løkken
Comment: Pyrite dissemination in greyish green, altered greenstone
No. of registrated element analyses = 1
LS91053 Bedrock
Sampler: Størseth, L.
Comment: Py mineralization in greenstone.
No. of registrated element analyses = 1
LS91054 Bedrock
Sampler: Størseth, L.
Comment: Fine grained pyrite in pale greenstone.
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:

Analyse Results
from
Deposit Area 5043 - 059 Gjersviktangen

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#
JS96029 Bedrock 35 81 -3 40 19 -.3 4.0
LS91053 Bedrock 155 77 2 71 14 .2 8.0
LS91054 Bedrock 40 443 2 16 4 .1 6.0
------------------
Sample No. Pt# Pd# Rh# As* Cd* Ba* Mo* Sb* Bi*
JS96029 -1.0 1.0 -1.0 7 .2 2 7.00 -2 -2
LS91053 1.0 2.0 4 .2 23 1.00 2 2
LS91054 2.0 2.0 2 .7 6 1.00 2 2
------------------
Sample No. S% V* Cr* Mn* Fe% Th* U* W* Sr*
JS96029 6.11 183 25 1019 12.00 2.00 -5.00 -2 9.0
LS91053 5.60 131 13 950 11.16 1.00 5.00 1 8.0
LS91054 3.32 155 6 689 7.46 1.00 5.00 1 3.0
------------------
Sample No. La* B*
JS96029 -1.00 -3
LS91053 2.00 2
LS91054 2.00 2

The fact sheet was created on 30.04.2024
Questions or comments regarding the fact sheet can be emailed to:
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