Norsk versjon | |||||
THE ORE DATABASE | |||||
Occurence 1813 - 021 Kråa | |||||
(Object Id: 2937) (Last updated: 15.05.2006) |
|
Location |
County: | Nordland | Municipality: | Brønnøy (1813) |
Map 1:50000: | Velfjord (1825-4) | Map 1:250000: | Mosjøen |
Coordinate system: | EU89-UTM Zone 33 |
East: | 385122 m. | North: | 7247598 m. |
Longitude: | 12.5328530 | Latitude: | 65.3310550 |
Show on map |
|
Resource |
Resource Type: | Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) | Resource Subtype: | Zinc | |
Element(s): | Zn Cu Kis |
Importance |
Raw material meaning: | Little Importance (reg. 18.02.2015) |
Resources and production |
Activity: | Exploration | Reserves: | ||
Operating method: | Historical production: |
Operations |
From - To | Activity | Comments | |
1982 - 1983 | Geochemistry | Company/Institution :BP Norge A/S Minerals | |
1983 - 1983 | Geochemistry | Company/Institution :BP Norge A/S Minerals | |
1994 - 1994 | Sampling | Company/Institution :NGU-malmreg. |
Mineralization |
Era: | Paleozoic | Period: | Ordovician | |
Genesis: | Replacement/Metasomatism | Form: | Lens | |
Main texture: | Structureless | Min. distribution: | Semi-massive (20-50 % ore minerals) |
Main grain size: | Medium grained (1-3 mm) | Main alteration: | Skarn formation |
Strike/Dip: | 16 / 90 | Direction: | ||
Plunge: |
Stratigraphic classification of host rock |
Era: | Paleozoic | Period: | Ordovician |
Province: | Caledonides | |
Geotec.unit: | Helgeland Nappe Complex | |
Tectonic complex: | ||
Igneous complex: | Bindal Batholith |
Group: | Formation: |
Mineralogy |
Relationship | Mineral | Amount | |
Gangue mineral | Pyroxene | Major mineral (>10%) | |
Gangue mineral | Feldspar | Subordinate mineral (1-10%) | |
Gangue mineral | Hornblende | Subordinate mineral (1-10%) | |
Ore mineral | Pyrrhotite | Major mineral (>10%) | |
Ore mineral | Sphalerite | Major mineral (>10%) | |
Ore mineral | Pyrite | Subordinate mineral (1-10%) | |
Ore mineral | Chalcopyrite | Subordinate mineral (1-10%) |
Lithology: |
Relationship | Rock | Origin | |
Host rock | Kalksilikatgneis | Sedimentary | |
Metamorphic facies :Contact | |||
Wall rock | Monzodioritt | Intrusive Original rock :Monzodiorite |
|
Wall rock | Marmor | Sedimentary Original rock :Limestone |
|
Metamorphic facies :Contact |
Structures |
Location: | Type: | Orientation(360 gr.): | Relation to min.: | |
Host rock | Mineral banding | Strike/Dip :7 / 15 | Pre-mineralisation ;...Effect :None | |
Host rock | Joints/Fractures | Strike/Dip :16 / 90 | Syn-mineralisation ;...Effect :Controls |
Information(s) in free text format |
Free text |
Forekomsten ble påvist av BP Norge A/S Minerals i forbindelse med oppfølging av bekkesedimentanomalier under gullprospektering i Helgeland 1981-84. Den opptrer innenfor en av de mange inneslutninger av marmor og båndete kalksilikatgneiser i Sausfjellet monzodiorittpluton. Mineralisering finnes over en lengde av 50 m i skjæringene langs tømmerveien mellom Hongset og Sørlia ved Fuglevatn og 50 m SV for plassen Kråa. Langs veien og Kråelva like i SV opptrer finbåndete (1-10 mm) grønnlige kalksilikatgneiser med små kropper og ganger av middels- til grovkornet monzodioritt. Kalksilikatgneisene fører 0,2-1 m brede og ca. N-S strykende soner med magnetkis-, litt kobberkis- og svovelkis-disseminasjon. Sonene opptrer ofte langs kontakten av monzodioritt som også inneholder disseminerte sulfider. Den rikeste mineraliseringen utgjøres av en 0,8 m bred og massiv sinkblendesone/linse (strøk/fall: 16/90) omgitt av sterk magnetkisdisseminasjon i middelskornet grønn klinopyroksen (diopsid) skarn. Kalksilikatgneisene/klinopyroksenskarnet gjennomsettes av opptil 3 cm brede kvarts- og kvarts-kalkspatårer med svart hornblenderand. Langs elven finnes også disseminert magnetkis i gneisene som gjennomsettes av granitt-pegmatittårer med små magnetkis- og svovelkis-aggregater. |
Bibliography: |
From NGU's Reference Archive: |
Myrland, Rolf , 1972 |
Velfjord. Beskrivelse til det berggrunnsgeologiske gradteigskart I 18 - 1:100 000. |
;Norges geologiske undersøkelse;KARTBESKRIVELSE; TIDSSKRIFTARTIKKEL;NGU; Skrifter; No.274; 1;1-30 + ka pages |
Abstract: | |
The various lithologies are described. These comprise granitic basements rocks of supposed Pre-Cambrian age and Cambro-Silurian supracrustals and intrusives. The intrusives are mostly found within the Bindal and Velfjord massifs. These massifs are younger than the supracrustals, but their mutual age relationship is uncertain. Tectonically the rocks are sitated in "the high metamorphic nappe-complex" of central and western Helgeland. The supracrustal rocks have undergone at least three phases of Caledonian folding, the F2 phase producing the main regional structures. The rocks have mineral assemblages which place them in the almandine-amphibolite metamorphic facies. |
Barnes, Calvin G.; Prestvik, Tore; Nordgulen, Øystein; Barnes, Melanie A. , 1992 |
Geology of three dioritic plutons in Velfjord, Nordland. |
;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU Bulletin; No.423;41-54 pages |
Abstract: | |
Dioritic plutons in the Velfjord area of Nordland intrude calc-silicates and migmatitic pelites of the Helgeland Nappe Complex (HNC). The three largest plutons were emplaced in a zone of NNW-SSE regional strike rather than the more typical NE-SW strike. The plutons postdate Caledonian F2 structures; however, anatectic granites increase in abundance toward the plutons, which suggests emplacement and subsequent partial melting of the pelitic host rocks soon after peak metamorphism. The dioritic and granitic bodies were deformed with interstitial melt present; deformation continued during cooling to greenschist facies conditions. Structural position, style and timing of deformation, and assymetric zoning of the plutons are consistent with intrusion into a dilatant part of a regional sinistral shear zone. |
Fieldsamples |
Sample No. | Sample type | Miscellanrous | ||||
NO0835.01 | Bedrock |
|
||||
NO0835.02 | Bedrock |
|
||||
NO0835.03 | Bedrock |
|
||||
NO0835.04 | Bedrock |
|
||||
NO0835.05 | Bedrock |
|
||||
NO0835.06 | Bedrock |
|
NB! All analyse values are shown at the end of the printout.: |
Name of Locality: Kråelva |
(Object Id: 3783 21,01,00) |
|
Location |
County: | Nordland | Municipality: | Brønnøy (1813) |
Map 1:50000: | Velfjord (1825-4) | Map 1:250000: | Mosjøen |
Coordinate system: | EU89-UTM Zone 33 |
East: | 385082 m. | North: | 7247608 m. |
Longitude: | 12.5319860 | Latitude: | 65.3311300 |
Show on map |
|
Resource |
Resource Type: | Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) | Resource Subtype: | Zinc | |
Element(s): | Zn Cu Kis |
Resources and production |
Activity: | Exploration | Reserves: | ||
Operating method: | Historical production: |
Analyse Results |
from |
Deposit Area 1813 - 021 Kråa |
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# |
NO0835.01 | Bedrock | 522 | 99999 | 42 | 36 | 19 | -.3 | 10.0 |
NO0835.02 | Bedrock | 1717 | 9435 | 8 | 348 | 101 | 1.2 | 18.0 |
NO0835.03 | Bedrock | 57 | 27 | 3 | 31 | 47 | -.3 | 12.0 |
NO0835.04 | Bedrock | 1094 | 937 | 40 | 58 | 63 | 1.0 | 11.0 |
NO0835.05 | Bedrock | 309 | 86 | 4 | 40 | 59 | .4 | 9.0 |
NO0835.06 | Bedrock | 279 | 19 | -3 | 32 | 25 | .6 | 14.0 |
------------------ |
Sample No. | Pt# | Pd# | Rh# | As* | Cd* | Ba* | Mo* | Sb* | Bi* |
NO0835.01 | -3.0 | 3.0 | -5.0 | 35 | 263.1 | 10 | 2.00 | -2 | 4 |
NO0835.02 | -3.0 | -3.0 | -5.0 | 8 | 18.7 | 5 | -1.00 | -2 | 9 |
NO0835.03 | -3.0 | -3.0 | -5.0 | -2 | -.2 | 23 | -1.00 | -2 | 2 |
NO0835.04 | -3.0 | -3.0 | -5.0 | 5 | 1.7 | 3 | -1.00 | -2 | -2 |
NO0835.05 | -3.0 | -3.0 | -5.0 | 4 | -.2 | 2 | -1.00 | -2 | -2 |
NO0835.06 | -3.0 | 3.0 | -5.0 | 2 | -.2 | 3 | 1.00 | -2 | -2 |
------------------ |
Sample No. | S% | V* | Cr* | Mn* | Fe% | Th* | U* | W* | Sr* |
NO0835.01 | 11.62 | 14 | 7 | 357 | 6.21 | 2.00 | -5.00 | 15 | 72.0 |
NO0835.02 | 16.74 | 8 | 10 | 70 | 26.59 | 2.00 | -5.00 | -2 | 28.0 |
NO0835.03 | 1.39 | 22 | 15 | 124 | 3.37 | -2.00 | -5.00 | -2 | 29.0 |
NO0835.04 | 8.63 | 24 | 6 | 156 | 15.72 | -2.00 | -5.00 | -2 | 33.0 |
NO0835.05 | 4.09 | 20 | 7 | 125 | 6.51 | 2.00 | 8.00 | -2 | 21.0 |
NO0835.06 | 6.73 | 4 | -1 | 116 | 10.81 | 4.00 | 5.00 | -2 | 13.0 |
------------------ |
Sample No. | La* | B* | |||||||
NO0835.01 | 15.00 | -3 | |||||||
NO0835.02 | 9.00 | 5 | |||||||
NO0835.03 | 6.00 | 4 | |||||||
NO0835.04 | 18.00 | -3 | |||||||
NO0835.05 | 16.00 | 4 | |||||||
NO0835.06 | 10.00 | -3 |
The fact sheet was created on 29.03.2024 |
Questions or comments regarding the fact sheet can be emailed to: ressursdatabaser@ngu.no |
Copyright © 2024 Geological Survey of Norway |