Norsk versjon | |||||
THE ORE DATABASE | |||||
Deposit Area 1635 - 037 | |||||
(Last updated 01.jul.1998) |
Name of Deposit Area : Bergstjern II |
(Object Id : 1635,037,00,00) |
Location |
County : | Sør-Trøndelag (16) | Municipality : | Rennebu (1635) |
Map 1:50000: | Innset (1520-2) | Map 1:250000: | Røros |
Marking point: | Longitude: | 10.0976850 | Latitude: | 62.6948420 |
EU89-UTM Zone 32 | (Coordinates IS confirmed) |
X-coord: | 556178 m. | Y-coord: | 6952068 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: | Not yet active | Volume of dump: | 2 m3 |
Importance |
Public: | Not Assessed (reg. 18.02.2015) |
Economical: | Not classified/evaluated |
Operations |
From - To | Activity | Comments | |
1983 - 1984 | Geophysics | Company/Institution :Folldal Verk A/S | |
1984 - 1984 | Geochemistry | Company/Institution :Folldal Verk A/S | |
1984 - 1985 | Sampling | Company/Institution :Folldal Verk A/S | |
1984 - 1985 | Geology | Company/Institution :Folldal Verk A/S | |
1987 - 1987 | Sampling | Company/Institution :NGU-Malmreg. |
Mineralization |
Era: | Period: | |||
Dating: | Method: | |||
Genesis: | Volcex | Form: | Layer | |
Main texture: | Banded | Min. distribution: | Massive (>50 % ore minerals) |
Main grain size: | Fine grained (< 1 mm) | Main alteration: | Sericitisation |
Strike/Dip: | 350 / 60 | Direction: | ||
Plunge: |
Stratigraphic classification of host rock |
Era: | Period: |
Province: | Caledonides | |
Geotec.unit: | Trondheim Nappe Complex | |
Tectonic complex: | Støren Nappe | |
Igneous complex: |
Group: | Støren | Formation: |
Mineralogy |
Relationship | Mineral | Amount | |
Gangue mineral | Quartz | Major mineral (>10%) | |
Gangue mineral | Feldspar | Subordinate mineral (1-10%) | |
Ore mineral | Pyrite | Major mineral (>10%) | |
Ore mineral | Pyrrhotite | Subordinate mineral (1-10%) | |
Ore mineral | Sphalerite | Accessory mineral (<1%) | |
Ore mineral | Chalcopyrite | Accessory mineral (<1%) |
Lithology: |
Relationship | Rock | Origin | |
Wall rock | Biotite schist | Sedimentary Original rock :Greywacke |
|
Metamorphic facies :Greenschist | |||
Wall rock | Greenschist | Extrusive Original rock :Tuff |
|
Metamorphic facies :Greenschist | |||
Wall rock | Sericite schist | Sedimentary Original rock :Tuffite |
|
Metamorphic facies :Greenschist |
Structures |
Location: | Type: | Orientation(360 gr.): | Relation to min.: | |
Wall rock | Foliation | Strike/Dip :350 / 60 | Post-mineralisation ;...Effect :None |
Information(s) in free text format |
Description |
Folldal Verk A/S / Amoco utførte i 1983 regionale geofysiske helikoptermålinger i området, som i 1984-85 ble fulgt opp med detaljundersøkelser mellom Nyberget gruve og Bergstjern. Stikningsnett ble opprettet, fulgt av geologisk detaljkartlegging, geofysiske målinger (VLF, Mag, CEM), fastfjell- og jordprøvetaking. Bergstjern II er et lite skjerp (1 m3 tipp) i skrent i sørkanten av ei myr. I skjerpet ses en ca. 30 cm mektig finkornig, massiv svovelkis-mineralisering, med et 5 cm mektig magnetkis-dominert lag langs hengkontakten. I mineraliseringen er små kvartsøyne vanlig. Det er enkelte glideplan /-speil i mineraliseringen, som løper parallelt med dens sidesteinskontakter. Hengbergart er finkornig biotittskifer, mens serisittskifer er liggbergart. Mineraliseringen kan pga. overdekning ikke følges langs strøket, men 300 m mot NNØ og få meter vest for bekken fra Bergstjern, er det et lite (<1 m3 tipp) skjerp (1) i det som antas å være omlag samme nivå som forrannevnte skjerp. Skjerpet er vannfylt og gjenrast og observasjoner er vanskelig å gjøre. Det er noe svovelkis-disseminasjon i kvarts-feltspatbåndet grønnskifer. Formen på skjerpet minner om fyrsetting. |
Bibliography: |
From NGU's Reference Archive: |
Nilsen, Odd , 1978 |
Caledonian sulphide deposits and minor iron-formations from the southern Trondheim region, Norway. |
;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.340;35-85 + k pages |
Abstract: | |
Within the southern and central parts of the Trondheim region of the Norwegian Caledonides a great number of small, stratabound cupriferous pyrite deposits are confined to mafic metavolcanics of the Gula, Støren and Fundsjø Groups of the Lower Palaeozoic succession. The deposits occuring within, or in close contact with the metavolcanics are characterized by their association with minor manganiferous oxide/silicate iron-formations - better known as "vasskis" ore type - within the metamorphic low-grade areas. The iron-fprmations of the metamorphic higher grade terrains on the other hand, which are extensively developed within the Gula Group, are mostly of a pyrrhotitic sulphide/silicate type and sulphurization processes are thought to have played an important role during the metamorphism. The pyrite deposits occurring adjacent to the metavolcanics bear no relationship to the iron-formations. They are embedded in pelitic, often carbonaceous assemblages (Gula Group) or within tuffitic members of the volcanogene Støren Group, and they are thought to represent re-sedimented (reworked) deposits. The pyrite deposits display varying degree of metamorphic reconstitution and a tectonic control has apparently determined their disc- or ruler-shaped morphology. |
References not to be found in NGU's Reference Archive.: |
Bakke, O. 1984: Oppdal project. Intern rapp. Folldal Verk A/S. BV 3018 |
Bakke, O. 1984: Oppdal prosjekt. Intern rapp. Folldal Verk A/S. BV 3019 |
Fieldsamples |
Sample No. | Sample type | Miscellanrous | ||||
ST0318.01 | Bedrock |
|
NB! All analyse values are shown at the end of the printout.: |
Name of Locality : |
(Object Id : 1635,037,01,00) |
Location |
County : | Sør-Trøndelag (16) | Municipality : | Rennebu (1635) |
Map 1:50000: | Innset (1520-2) | Map 1:250000: | Røros |
Marking point: | Longitude: | 10.0995400 | Latitude: | 62.6974300 |
EU89-UTM Zone 32 | (Coordinates IS confirmed) |
X-coord: | 556268 m. | Y-coord: | 6952358 m. |
|
Commodity |
Main Type: | Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) | Sub Type: | Sulphides | |
Element(s): | Kis |
Analyse Results |
from |
Deposit Area 1635 - 037 Bergstjern II |
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# |
ST0318.01 | Bedrock | 131 | 366 | 45 | 8 | 43 | .4 | 135.0 |
------------------ |
Sample No. | Pt# | Pd# | As* | Cd* | Ba* | Mo* | Sb* | Bi* | S% |
ST0318.01 | 3.0 | 11.0 | 152 | .7 | 2 | 1.00 | 7 | 14 | 40.50 |
------------------ |
Sample No. | V* | Cr* | Mn* | Fe% | Th* | U* | W* | Sr* | La* |
ST0318.01 | 29 | 12 | 203 | 24.65 | 7.00 | -8.00 | 3 | 3.0 | 2.00 |
------------------ |
Sample No. | B* | ||||||||
ST0318.01 | -3 |
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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