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	THE ???? DATABASE
	Deposit 0 - 000 FEIL
	(Object Id: ) (Last updated: 15.03.2024)

Products

	Element/product	Crude ore grade or quality	Reg. date
	Mo	0.09 %	13.03.2024
	MoS2	0.14 %	10.05.2001

Operations

	From - To	Activity	Comments
	1978 - 1980	Detail mapping	Company/Institution :Norsk Hydro a.s.
	1978 - 1983	Geochemistry	Company/Institution :Norsk Hydro a.s.
			6000 soil samples has been collected over the deposit and in adjacent areas.
	1978 - 1983	Geology	Company/Institution :Norsk Hydro a.s.
	1978 - 1983	Core drilling	Company/Institution :Norsk Hydro a.s.
			The deposit has been investigated by 24 drill holes totalling 10200 m.
	1979 - 1982	Geophysics	Company/Institution :Norsk Hydro a.s.
			Mainly IP ground surveys

Mineralization

	Era:	Paleozoic	Period:	Permian
	Genesis:	Porphyry-type	Form:	Irregular
	Main texture:	Fracture filling	Min. distribution:	Disseminated (<20 % ore minerals)

Main grain size:

Fine grained (< 1 mm)

Main alteration:

Sericitisation

	Strike/Dip:		Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Paleozoic

Period:

Permian

	Province:	Oslo Region
	Geotec.unit:	Akershus Graben
	Tectonic complex:
	Igneous complex:	Nordmarka-Hurdal Batholith

Group:

Formation:

Mineralogy

	Relationship	Mineral	Amount
	Gangue mineral	Quartz	Major mineral (>10%)
	Gangue mineral	Sericite	Major mineral (>10%)
	Gangue mineral	Potassic feldspar	Major mineral (>10%)
	Gangue mineral	Biotite	Subordinate mineral (1-10%)
	Gangue mineral	Feldspar	Subordinate mineral (1-10%)
	Ore mineral	Molybdenite	Major mineral (>10%)
	Ore mineral	Pyrite	Major mineral (>10%)
	Ore mineral	Hematite	Subordinate mineral (1-10%)
	Ore mineral	Wolframite	Accessory mineral (<1%)

Lithology:

	Relationship	Rock	Origin
	Host rock	Biotite granite	Intrusive Original rock :Biotite granite
			Metamorphic facies :Unmetamorphosed
	Host rock	Hornblende-biotite syenite	Intrusive Original rock :Syenite
			Metamorphic facies :Unmetamorphosed
	Host rock	Intrusive breccia	Intrusive
			Metamorphic facies :Unmetamorphosed
	Host rock	Granophyre	Intrusive Original rock :Granophyre
			Metamorphic facies :Unmetamorphosed
	Host rock	Quartz-eye alkali granite	Intrusive Original rock :Alkali granite
			Metamorphic facies :Unmetamorphosed
	Host rock	Aplogranite	Intrusive Original rock :Aplite
			Metamorphic facies :Unmetamorphosed
	Host rock	Micro-granite	Intrusive Original rock :Granite
			Metamorphic facies :Unmetamorphosed
	Wall rock	Alkali granite	Intrusive Original rock :Alkali granite
			Metamorphic facies :Unmetamorphosed
	Wall rock	Alkali-granite porphyry	Intrusive Original rock :Alkali granite
			Metamorphic facies :Unmetamorphosed
	Wall rock	Alkali granite porphyry	Intrusive Original rock :Porphyry granite
			Metamorphic facies :Unmetamorphosed

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Host rock	Joints/Fractures	Strike/Dip :140 / 80	Syn-mineralisation ;...Effect :Modifies
	Host rock	Joints/Fractures	Strike/Dip :300 / 80	Syn-mineralisation ;...Effect :Modifies

Information(s) in free text format

Free text

The Nordli deposit was discovered by Norsk Hydro a.s. in 1978 and became the site of extensive exploration until 1983. The drift-covered deposit was investigated by 24 drill holes totalling 10200 m, extensive geophysical ground surveys, more than 6000 soil samples and by detailed (1:10 000) bedrock mapping in an area exceeding 400 km2. The core drilling showed that the deposit represents a low grade granite-related molybdenite mineralisation with reserves totalling c. 200 Mt with 0.14% MoS2 at a cut off at 0.05%. It shows many similarities with porphyry Mo systems of the western United States. The deposit formed in a sub-volcanic environment in the root zone of a deeply eroded and nested system of calderas in the northern part of the Nannestad-Hurdal batholith. The molybdenite mineralisation is according to Pedersen (1986) related to the emplacement and crystallisation of the composite Nordli alkali-granite stock which postdates the major caldera-forming processes. Core drilling has demonstrated that the mineralisation comprise three 150-250m thick and irregularly shaped shells with an diameter of 200-300m, situated above each other over a vertical distance of c. 900 m. They are connected along their northeastern periphery by a steeply dipping ore zone extending from the middle ore shell and following the Høverelven fault zone (N 120-140 E). The ore shells which comprise high intensity of molybdenite-bearing quartz veins and fractures coatings, is analytically defined at 0.05% MoS2. The individual shells occur shortly above areas with high intensity of quartz veins and are surrounded and overlain by a telescoped system of different types of K-silicate and phyllic alteration, containing variable amounts of magnetite, pyrite and hematite. At and near the surface the peripheral parts of the system are dominated by argillic alteration. The development of the deposit as given below, is taken from Pedersen (1986): The Nordli stock forms part of the magmatic center which developed along the Høverelven fracture zone. The first event in this centre was the intrusion of a volatile laden, highly alkalic and silica-rich stock consisting of quartz-eye granite. It is transected and partly obliterated by a diatreme that formed as a consequence of phreatic explosions related to the rapid emplacement of granite porphyry intrusions. Soon afterwards, the Nordli stock intruded the intrusive breccias in the diatreme, forming a composite body of highly differentiated granites with a diameter of 400 m and a vertical extent of more than 1000 m. The first granophyric phase reached a shallow level and exsolved during crystallisation a water-rich supercritical vapour that escaped to form an upper ore shell extending from the present surface and 200 m downwards. The low-grade upper ore shell comprises numerous steeply dipping and flat-lying veinlets of quartz, pyrite, hematite, magnetite and/or molybdenite. A second aplo-granite phase transects the granophyre 150 m below the present surface. Fluids emanating from the crystallising granite gave rise to the middle ore shell which is composed of steeply dipping, ribbon-type veinlets consisting of molybdenite and quartz, pyrite, sericite, biotite and/or K-feldspar. The release of volatiles from the aplo-granite is believed to have been triggered by movements along the Høverelva fault zone. This is suggested by the more than 600 m vertical extention of the middle ore shell and by widespread evidence of semi-brittle to cataclastic deformation of the granophyre, the ribbon veinlets and the aplo-granite. Following the emplacement of the aplo-granite, weakly renewed explosive activity with formation of intrusive breccias occurred. Then a third micro-granitic phase of the Nordli stock intruded to a level of about 600 m below the present surface. Fluids from the micro-granite was responsible for the formation of the lower ore shell which comprises a stockwork of cavernous veinlets, composed of molybdenite, quartz, calcite, K-feldspar, magnetite and pyrite. Finally, a late phase of volatile-depleted porphyritic micro-granite intruded the deepest part of the system and partly crosscut the richest molybdenite mineralisation in the deposit. The Nordli deposit is currently (2008) being investigated by Intex Resources. See http://www.intexresources.com/news.cfm?id=94

Bibliography:

References not to be found in NGU's Reference Archive.:

Pedersen, D.F., 1986: An Outline of the geology of the Hurdal area and the Nordli granite molybdenite deposit. In: Olerud, S. and Ihlen, P. M. (eds), Metallogeny associated with the Oslo Paleorift; Sveriges geologiska undersökning, Ser. Ca 59, 18-25.

Intex Resources web page: http://www.intexresources.com/news.cfm?id=94

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	NL21-001	Bedrock	Sampler: Y. Cheng/...Stored: Løkken Comment: Granophyre with Mo vein and disseminated pyrite No. of registrated element analyses = 1

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

Name of Sample point: Prøvepunkt

(Object Id: 39169 6,00,01)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Hurdal (1915-4)

Map 1:250000:

Hamar

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Ferroalloys (Cr,Ni,Co,V,Mo,W)	Resource Subtype:	Molybdenium
			Element(s):	Mo

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	NL21-004	Bedrock	Sampler: Y. Cheng/...Stored: Løkken Comment: Feldspar porphyry with Mo-bearing quartz vein No. of registrated element analyses = 1

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

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The fact sheet was created on 20.04.2024

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