Norsk versjon
THE ORE DATABASE
Occurence 1826 - 034 Sommarfjelltoppen
(Object Id: 2950)
(Last updated: 01.03.2000)

Location
County: Nordland Municipality: Aarborte (1826)
Map 1:50000: Susendalen (1925-1) Map 1:250000: Mosjøen
Coordinate system: EU89-UTM Zone 33
East: 456402 m. North: 7261098 m.
Longitude: 14.0588940 Latitude: 65.4694230
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Resource
Resource Type: Precious metals (Au,Ag,PGE) Resource Subtype: Silver
Element(s): Ag Pb Zn Cu Sb
Importance
Raw material meaning: Not Assessed (reg. 18.02.2015)

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


Operations
From - To Activity Comments
1880 - 1881 Sampling Company/Institution :Sommarfjelltoppen Grubebolag

Mineralization
Era: Paleozoic Period: Ordovician
Genesis: Unknown Form: Irregular
Main texture: Fracture filling Min. distribution: Disseminated (<20 % ore minerals)
Main grain size: Medium grained (1-3 mm) Main alteration: Carbonatisation
Strike/Dip: 277 / 90 Direction:
Plunge:
Stratigraphic classification of host rock
Era: Paleozoic Period: Ordovician
Province: Caledonides
Geotec.unit: Køli Nappe Complex
Tectonic complex: Hattfjelldaldekket
Igneous complex:
Group: Limingen Formation: Finnburvika

Mineralogy
Relationship Mineral Amount
Gangue mineral Carbonate Major mineral (>10%)
Gangue mineral Quartz Subordinate mineral (1-10%)
Ore mineral Galena Major mineral (>10%)
Ore mineral Sphalerite Major mineral (>10%)
Ore mineral Malachite Subordinate mineral (1-10%)
Ore mineral Fahlore Subordinate mineral (1-10%)
Ore mineral Chalcopyrite Subordinate mineral (1-10%)
Ore mineral Azurite Subordinate mineral (1-10%)

Lithology:
Relationship Rock Origin
Host rock Dolomittbreksje Sedimentary
Original rock :Sedimentary breccia
Metamorphic facies :Greenschist
Wall rock Klorittskifer Sedimentary
Original rock :Tuffite
Metamorphic facies :Greenschist
Wall rock Dolomitt Sedimentary
Original rock :Dolomite
Metamorphic facies :Greenschist

Structures
Location: Type: Orientation(360 gr.): Relation to min.:
Host rock Shear plane Strike/Dip :60 / 80 Syn-mineralisation ;...Effect :Controls
Host rock Primary layering Strike/Dip :186 / 30 Pre-mineralisation ;...Effect :None
Host rock Fault plane Strike/Dip :277 / 90 Syn-mineralisation ;...Effect :Controls

Information(s) in free text format
Free text
Skjerpet ble drevet på 1880-tallet av Sommarfjelltoppen Grubebolag i forbindelse med leting etter sølv-malmer i Susendalen. En liten synk på 2,5x2 m2 og med dybde på 3 m utgjør hovedskjerpet, mens en grunn skjæring på 1,5x15 m2 i N-S-retning utgjør Nedre skjerp som ligger 40 m vest for hovedskjerpet. Begge skjerpene ligger over tregrensen øverst i lia mot toppen. Mellom skjerpene finnes det et par grunne røsker. Mineraliseringene opptrer i en karbonatbreksje bestående av dolomittfragmenter i en karbonat matriks. Dolomittbreksjen, som finnes langs hele fjellsiden, opptrer i veksellagring med massiv dolomitt og tynne klorittskifer-bånd og horisonter. Mineraliseringen opptrer i tilknytning til en Ø-V-strykende og steiltstående forkastning og assosierte skjærsoner. Den omfatter blyglans og noe sinkblende og kobberkis som danner sprekkefyllinger og dels sulfidsement i omgivende dolomittbreksjer som lokalt er ankerittomvandlet, dvs. brunforvitret karbonat. Karbonatbergartene er i hele fjellsiden gjennomsatt av et spredt nett med kvartsårer som i nedre skjerp omgis av litt silifisert dolomitt. Bare ett sted i skjerpene ble det funnet et par blyglansfylte sprekker i disse.

Bibliography:
From NGU's Reference Archive:
Dallmann, Winfried K. , 1987
Sedimentary environment and synsedimentary tectonics in the Hattfjelldal Nappe, North-Central Norway.
;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU Bulletin; No.410;25-54 pages
Abstract:
The Hattfjelldal Nappe, part of the "eugeoclinical" Seve-Köli Nappe Complex of the Scandinavian Caledonides, occurs beneath the basal thrust zone of the Helgeland Nappe Complex. Detailed fieldwork in these strongly deformed rocks has allowed recognition of a stratigraphic succession which partly can be correlated with successions adjacent nappes and other areas in the Central and North Scandinavian Caledonides. Two main groups can be recognized. The Røssvatnet Group is assumed to represent an Early Silurian carbonate tidal-flat and adjcent basinal environment, possibly situated upon a former accreted island arc/continental margin complex. Scandian tectonism is considered to have commenced subsequently, with the westward tilting of the depositional area which gave rise to a sedimentary unconfirmity (base of Limingen Group) and the development of psephitic massgravity sediments. The Limingen Group is considered to represent a transition from flysch to molasse facies, where sediments were derived from the advancing nappe front of the Helgeland Nappe Complex to the west. Sedimentation then ceased as the basin was overthrust in the Mid Silurian and truncated by the nappes, which gave rise to a post-sedimentary polyphase deformation sequence.

Bathen, E. , 1881
Kort beretning om de vigtigste grubebolag i Vefsen og Hatfjelddalen.
;Norges geologiske undersøkelse;RAPPORT;Bergarkivet; No.BA 1719;64 pages
Abstract:
Dokumentet er en trykksak med opplysninger, tatt vesentlig fra Helgelands Tidende, om de viktigste grubeselskaper i Vefsn og Hattfjelldalen.

Fieldsamples
Sample No. Sample type Miscellanrous
39/9089695 Dump
Sampler: Ihlen, P.M./...Stored: Løkken
39/9089696 Dump
Sampler: Ihlen, P.M./...Stored: Løkken
39/90896976 Dump
Sampler: Ihlen, P.M./...Stored: Løkken
39/9089698 Dump
Sampler: Ihlen, P.M./...Stored: Løkken
39/9089699 Dump
Sampler: Ihlen, P.M./...Stored: Løkken

Name of Locality: Nedre skjerp
(Object Id: 3785 34,01,00)

Location
County: Nordland Municipality: Aarborte (1826)
Map 1:50000: Susendalen (1925-1) Map 1:250000: Mosjøen
Coordinate system: EU89-UTM Zone 33
East: 456362 m. North: 7261088 m.
Longitude: 14.0580340 Latitude: 65.4693280
Show on map

Resource
Resource Type: Precious metals (Au,Ag,PGE) Resource Subtype: Silver
Element(s): Ag Pb Zn Cu Sb
Resources and production
Activity: Pitting Reserves:
Operating method: Historical production:


The fact sheet was created on 27.10.2021

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