Fact Sheet for Deposit Area 1837

					Norsk versjon
	THE INDUSTRIAL MINERAL DATABASE
	Deposit Area 1837 - 315
	(Last updated 25.feb.2004)

Name of Deposit Area : Kobbetuva

(Object Id : 1837,315,00,00)

Location

County :

Nordland (18)

Municipality :

Meløy (1837)

Map 1:50000:

Svartisen (1928-2)

Map 1:250000:

Mo i Rana

Marking point:

Longitude:

13.8797370

Latitude:

66.7225950

EU89-UTM Zone 33

(Coordinates NOT confirmed)

X-coord:

450599 m.

Y-coord:

7400899 m.

Commodity

Main Type:

Olivine

Sub Type:

Ultramafic (unspec.)

Importance

Public: Not Assessed (reg. 18.02.2015)

Economical: Not classified/evaluated

Mineralization

Era: Period:

Dating: Method:

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Stratigraphic classification of host rock

Era: Period:

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Bibliography:

From NGU's Reference Archive:

Bucher-Nurminen, Kurt , 1988

Metamorphism of ultramafic rocks in the Central Scandinavian Caledonides

;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;Special publication; No.3;86-95 pages

Abstract:

Lenses and boudins of ultramafic rocks in the Central Scandinavian Caledonides (CSC) represent parts of dismembered ophiolite sequences and fragments of sub- continental upper mantle. The metaperidotites are isofacial with the metamorp- hic envelope, usually metasediments but in place also metagranitoids. Metamorphic assemblages in metaperidotites of the CSC, together with additional geological constraints, define a regional metamorphic gradient of prograde metamorphism which passes through the approximate PT-coordinates (in C and kbars): 400/4, 500/6, 600/8, 700/9. The sequence of prograde metamorphic assemblages is (with increasing temperature): antigorite+brucite, antigorite+ forsterite, forsterite+talc, forsterite+enstatite+chlorite, and forsterite+ enstatite+green spinel. The maximum temperature was not sufficient to replace calcic amphibole by calcic pyroxene. Pargasite overgrowth on earlier tremolite demonstrates the prograde nature of the metamorphism. Most of the ultramafic rocks probably represent progresively metamorphosed serpentinites (mantle-or crustal serpentinites?). The regional distribution of assemblages in the ultramafic rocks of the CSC defines a regular pattern which cross-cuts the nappe boundaries of the area.

Johnsen, S.O. , 1983

Svartisen. Berggrunnskart; Svartisen; 19282; 1:50 000; sort/hvitt;

;Norges geologiske undersøkelse;KART

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