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THE ORE DATABASE
Occurence 5043 - 011 Slåttmyrtangen
(Object Id: 245)
(Last updated: 04.05.2006)
Location
County: Trøndelag Municipality: Raarvihke (5043)
Map 1:50000: Tunnsjøen (1924-3) Map 1:250000: Grong
Coordinate system: EU89-UTM Zone 33
East: 415312 m. North: 7173409 m.
Longitude: 13.2254720 Latitude: 64.6749000
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: Little Importance (reg. 18.02.2015)

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


Operations
From - To Activity Comments
1991 - 1991 Sampling Company/Institution :NGU

Mineralization
Era: Paleozoic Period: Ordovician
Genesis: Volcex Form: Layer
Main texture: Banded Min. distribution: Massive (>50 % ore minerals)
Main grain size: Fine grained (< 1 mm) Main alteration: Chloritisation
Strike/Dip: 70 / 50 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 Chlorite Subordinate mineral (1-10%)
Ore mineral Pyrite Major mineral (>10%)

Lithology:
Relationship Rock Origin
Wall rock Greenstone Extrusive
Original rock :Basalt
Metamorphic facies :Greenschist
Wall rock Mafic tuff Extrusive
Original rock :Tuff
Metamorphic facies :Greenschist

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

Information(s) in free text format
Free text
Forekomsten ligger på et svaberg helt nede ved Tunnsjøen, 550 m rett sør for toppen av Slåttmyrhøgda. Nåes lett pr. båt, eller til fots i 20-25 min. fra riksvei ved å følge ei myr hele veien. Det er en 1-1.5 m tykk vasskishorisont hvor fin- og grovkornet massiv malm veksler med mindre partier disseminert malm. Mineraliseringen er i kontakt med båndet, tuffittisk grønnstein og massiv, mørk grønnstein som er svakt klorittisert. Horisonten i grønnstein synes å ha liten utbredelse lateralt (<100 m?).

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
HK90-240 Bedrock
Sampler: Karlstrøm, H.
Comment: Massive, fine grained pyrite ore, locally bands with recrystalized pyrite. Central zone.
No. of registrated element analyses = 1
HK90-241 Bedrock
Sampler: Karlstrøm, H.
Comment: Massive, medium to fine grained pyrite ore. Central zone.
No. of registrated element analyses = 1
HK90-242 Bedrock
Sampler: Karlstrøm, H.
Comment: Veinlets of medium grained pyrite im pyrite disseminated, massive greenstone. Footwall.
No. of registrated element analyses = 1
HK90-243S Bedrock
Sampler: Karlstrøm, H.
Comment: Chip sample.
No. of registrated element analyses = 1
LS91125 Bedrock
Sampler: Størseth, L.R.
Comment: Fine grained pyrite ore.
No. of registrated element analyses = 1
LS91126 Bedrock
Sampler: Størseth, L.R.
Comment: Coarse grained pyrite ore.
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:

Analyse Results
from
Deposit Area 5043 - 011 Slåttmyrtangen

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#
HK90-240 Bedrock 243 20 14 12 30 .7 30.0
HK90-241 Bedrock 499 292 16 6 37 .5 27.0
HK90-242 Bedrock 348 113 2 9 86 .2 8.0
HK90-243S Bedrock 427 211 12 34 50 .4 23.0
LS91125 Bedrock 277 45 12 55 83 .5 30.0
LS91126 Bedrock 1466 72 4 24 174 .4 20.0
------------------
Sample No. Pt# Pd# As* Cd* Ba* Mo* Sb* Bi* S%
HK90-240 2.0 2.0 69 .2 1 1.00 5 2 26.52
HK90-241 3.0 4.0 76 1.1 6 2.00 2 2 38.18
HK90-242 1.0 2.0 102 1.4 11 15.00 2 2 14.63
HK90-243S 1.0 2.0 90 1.1 6 2.00 2 2 28.82
LS91125 1.0 1.0 139 .2 5 10.00 2 2 34.62
LS91126 1.0 2.0 290 .2 1 16.00 2 2 33.26
------------------
Sample No. V* Cr* Mn* Fe% Th* U* W* Sr* La*
HK90-240 18 10 190 18.69 3.00 5.00 1 10.0 2.00
HK90-241 51 20 459 20.74 3.00 5.00 1 4.0 2.00
HK90-242 69 125 949 15.05 1.00 5.00 1 5.0 2.00
HK90-243S 45 39 520 18.82 2.00 5.00 1 8.0 2.00
LS91125 56 64 638 23.10 1.00 5.00 1 8.0 2.00
LS91126 62 32 907 23.92 1.00 5.00 1 2.0 2.00
------------------
Sample No. B*
HK90-240 3
HK90-241 2
HK90-242 2
HK90-243S 2
LS91125 3
LS91126 5

The fact sheet was created on 08.05.2024
Questions or comments regarding the fact sheet can be emailed to:
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