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English version | ||||
| MALMDATABASEN | |||||
| Forekomstområde 1635 - 031 | |||||
| (Sist oppdatert 16.feb.2005) | |||||
Navn på deposit area : Bergstjern IV |
| (Objekt Id : 1635,031,00,00) |
| Lokalisering |
| Fylke : | Sør-Trøndelag (16) | Kommune : | Rennebu (1635) |
| Kart 1:50000: | Innset (1520-2) | Kart 1:250000: | Røros |
| Markeringspunkt: | Lengdegrad: | 10.0881720 | Breddegrad: | 62.7018280 |
| EU89-UTM Zone 32 | (Coordinates IS confirmed) |
| X-koord: | 555678 m. | Y-koord: | 6952838 m. |
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| Materialtype |
| Hovedtype: | Jernmetaller (Fe, Mn, Ti) | Subtype: | Jern | |
| Element(s): | Fe |
| Production |
| Activity: | Røsking | Reserves: | ||
| Prod. method: | Production: | |||
| Prod. status: | Ikke satt i drift | Volume of dump: | 10 m3 |
| Betydning |
| Offentlig: | Not Assessed (reg. 18.02.2015) |
| Economical: | Ikke vurdert , (Confirmed 16.feb.2005 by Agnes Raaness) |
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 | |
| 1997 - 1997 | Sampling | Company/Institution :NGU-Malmreg. |
Mineralization |
| Era: | Period: | |||
| Dating: | Method: | |||
| Genesis: | Vulkeks | Form: | Lag | |
| Main texture: | Båndet | Min. distribution: | Semi-massiv |
| Main grain size: | Finkornet (<1 mm) | Main alteration: |
| Strike/Dip: | 30 / 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%) | |
| Ore mineral | Magnetite | Major mineral (>10%) | |
| Ore mineral | Pyrite | Subordinate mineral (1-10%) |
Lithology: |
| Relationship | Rock | Origin | |
| Host rock | Chert | Sedimentary Original rock :Exhalite |
|
| Metamorphic facies :Greenschist | |||
| Wall rock | Greenstone | Extrusive Original rock :Basalt |
|
| Metamorphic facies :Greenschist |
Structures |
| Location: | Type: | Orientation(360 gr.): | Relation to min.: | |
| Host rock | Foliation | Strike/Dip :30 / 60 | Post-mineralisation ;...Effect :None |
Opplysning(er) i fritekstformat |
| Beskrivelse |
| 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 detaljgeologisk kartlegging, geofysiske målinger (VLF, Mag, CEM), fastfjell- og jordprøvetaking. Bergstjern IV er en kvartsbåndet magnetitt-mineralisering som er undersøkt med en 4 x 2 m2 stor synk, som er vannfylt og utilgjengelig. Observasjoner av tippmaterialet viser en blågrå chert med opptil 10 cm mektige bånd av finkornig, massiv magnetitt og litt svovelkis. Vanligvis er magnetittbåndingen i mm- til cm-skala. Svovelkis, som 1-2 mm store euhedrale krystaller, er vanlig opptredende i cherten. Denne cherthorisonten med magnetittbånding er også blottet et par steder ca. 250 m mot nord. |
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 | ||||
| ST0364.01 | Dump |
|
| NB! All analyse values are shown at the end of the printout.: |
Analyse Results |
| from |
| Forekomstområde 1635 - 031 Bergstjern IV |
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# |
| ST0364.01 | Dump | 37 | 138 | 42 | 27 | 94 | -.3 | 3.0 |
| ------------------ |
| Sample No. | Pt# | Pd# | As* | Cd* | Ba* | Mo* | Sb* | Bi* | S% |
| ST0364.01 | 6.0 | -1.0 | 5 | 1.0 | 590 | 1.00 | -3 | 21 | .16 |
| ------------------ |
| Sample No. | V* | Cr* | Mn* | Fe% | Th* | U* | W* | Sr* | La* |
| ST0364.01 | 249 | 43 | 1707 | 42.49 | 10.00 | -8.00 | 2 | 40.0 | 9.00 |
| ------------------ |
| Sample No. | B* | ||||||||
| ST0364.01 | 15 |
| Faktaarket ble generert 13.06.2026 |
| Spørsmål eller kommentarer vedrørende faktaarket kan mailes til: ressursdatabaser@ngu.no |
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