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	THE ORE DATABASE
	Deposit Area 1635 - 042
	(Last updated 01.jul.1998)

Importance

Public:

Not Assessed (reg. 18.02.2015)

Economical:

Not classified/evaluated

Operations

	From - To	Activity	Comments
	1997 - 1997	Sampling	Company/Institution :NGU-Malmreg.

Mineralization

	Era:		Period:
	Dating:		Method:
	Genesis:	Volcex	Form:	Layer
	Main texture:	Banded	Min. distribution:	Semi-massive (20-50 % ore minerals)

Main grain size:

Fine grained (< 1 mm)

Main alteration:

	Strike/Dip:		Direction:	130
			Plunge:	20

Stratigraphic classification of host rock

Era:

Period:

	Province:	Caledonides
	Geotec.unit:	Blåhø-Surna Nappe Complex
	Tectonic complex:	Blåhø Nappe
	Igneous complex:

Group:

Blåhø

Formation:

Mineralogy

	Relationship	Mineral	Amount
	Gangue mineral	Quartz	Major mineral (>10%)
	Gangue mineral	Feldspar	Subordinate mineral (1-10%)
	Gangue mineral	Biotite	Subordinate mineral (1-10%)
	Gangue mineral	Amphibole	Subordinate mineral (1-10%)
	Gangue mineral	Carbonate	Accessory mineral (<1%)
	Ore mineral	Pyrrhotite	Major mineral (>10%)
	Ore mineral	Pyrite	Accessory mineral (<1%)
	Ore mineral	Chalcopyrite	Accessory mineral (<1%)

Lithology:

	Relationship	Rock	Origin
	Host rock	Quartzite	Sedimentary Original rock :Exhalite
			Metamorphic facies :Amphibolite
	Wall rock	Garbenschiefer	Extrusive Original rock :Tuff
			Metamorphic facies :Amphibolite
	Wall rock	Amphibole schist	Extrusive Original rock :Tuff
			Metamorphic facies :Amphibolite

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Host rock	Fold axis	Dir./Plunge :130 / 20	Post-mineralisation ;...Effect :Modifies

Information(s) in free text format

Description

Skjerpet, som er en 10 m lang N-S-gående avblotningsgrop som følger mineraliseringen, ligger 20 m øst for ei hytte ved NV-enden av Hestvatnet. Den stratabundne kismineraliseringen er 20 cm mektig og består av 4 tynne (opptil 5 cm mektige) lag av massiv magnetkis med små (opptil 1 mm) kvartsøyne, og med litt svovelkis og kobberkis mobilisert på hårtynne sprekker, og ellers disseminasjon (til semimassive partier) av magnetkis i kvartsitt og kvarts-feltspatbergart innen den tynne malmsonen (som også fører litt karbonat). Hengbergart er finbladig amfibolskifer med mm-mektige kvartslag og karbonatflekker, mens liggbergart er garbenskifer (kvarts-feltspatgneis med biotittlaminering og store amfibolnåler). I skjerpet følger mineraliseringen ombøyningen i en åpen fold (akse 130/20), hvor lagene dreier fra N-S-strykende med slakt østlig fall til Ø-V-strykende med slakt sørlig fall. Mineraliseringen er ikke blottet utenfor skjerpet.

Bibliography:

From NGU's Reference Archive:

Nilsen, Odd , 1988

	The tectonostratigraphic setting of stratabound sulphide deposits in the southern Trondheim region, Central Norwegian Caledonides.

;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU Bulletin; No.412;55-66 pages

Abstract:

The large number of mainly massive, polymetallic, stratabound sulphide deposits within the southern Trondheim region are spatially confined to the different nappe units of the central Scandinavian Caledonides. The rocks of the parautochthon and Lower Allochthon comprise metasandstones and arkoses which are virtually barren of any sulphide mineralizations, except for a few showings of "sandstone lead" disseminations. The middle and lowermost parts of the upper Allochton are dominated by sediment-hosted chalcopyrite/pyrrhotite assemblages within calcareous mixed peltic and psammitic rocks with minor mafic metavolcanic and plutonic intercalations. The structurally higher Gaula and Støren units of the Trondheim Nappe complex of the upper Allochthon contain chiefly pyrite-dominated assemblages in mafic and mixed mafic/felsic volcanogenic settings and have highly variable Cu, Zn and Pb contents. The stratabound sulphides of the Trondheim region were deposited during successive stages and within restricted sedimentary and volcanosedimentary environments related to development of the lapetus Ocean. Deposition started in basin sediments during Late Proterozoic rifting, but was mainly the result of early subduction and the development of an active island-arc magmatism in the Early Ordovician. The structural and stratigraphical sequences were subsequently affected by Caledonian folding and metamorphism prior to and during eastward transport as composite nappe units in Silurian times. The postdepositional tectonic and metamorphic events have affected the different ores and their wallrocks to various degree as revealed by apparent tectonic control and the internal metamorphic fabric of the deposits.

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	ST0206.01	Bedrock	Sampler :Wilberg/...Stored :Løkken Comment :Fink. massiv po-min. No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

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Analyse Results

from

Deposit Area 1635 - 042 Storlia

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#
ST0206.01	Bedrock	796	31	-3	31	236	-.3	3.0

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Sample No.	Pt#	Pd#	As*	Cd*	Ba*	Mo*	Sb*	Bi*	S%
ST0206.01	11.0	3.0	2	-.2	4	8.00	-3	6	25.20

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Sample No.	V*	Cr*	Mn*	Fe%	Th*	U*	W*	Sr*	La*
ST0206.01	43	17	401	37.74	8.00	-8.00	2	15.0	6.00

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Sample No.	B*
ST0206.01	10

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The fact sheet was created on 19.05.2024

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