English version
	MALMDATABASEN
	Forekomstområde 238 - 010
	(Sist oppdatert 19.des.2022)

Betydning

Offentlig:

Not Assessed (reg. 18.02.2015)

Economical:

Lite viktig , (Confirmed 26.aug.2021 by Jan Sverre Sandstad)

Mineralization

	Era:	Paleozoic	Period:	Permian
	Dating:		Method:
	Genesis:	Skarnmalm	Form:	Linse
	Main texture:	Strukturløs	Min. distribution:	Semi-massiv

Main grain size:

Finkornet (<1 mm)

Main alteration:

Skarnomvandling

	Strike/Dip:		Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Paleozoic

Period:

Ordovician

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

Group:

Formation:

Mineralogy

	Relationship	Mineral	Amount
	Gangue mineral	Pyroxene	Major mineral (>10%)
	Gangue mineral	Calcite	Accessory mineral (<1%)
	Ore mineral	Sphalerite	Major mineral (>10%)
	Ore mineral	Pyrrhotite	Subordinate mineral (1-10%)
	Ore mineral	Pyrite	Subordinate mineral (1-10%)

Lithology:

	Relationship	Rock	Origin
	Host rock	Hednebergittskarn	Sedimentary Original rock :Limestone
			Metamorphic facies :Contact
	Wall rock	Hornfels	Sedimentary Original rock :Argillaceous sediment
			Metamorphic facies :Contact

Opplysning(er) i fritekstformat

Fri tekst

Forekomsten ligger i en ca. 500x150 m stor xenolitt av hornfels, som er omdannede kambriske til undersiluriske alunskifre med kalksteinslinser, i forskjellige permiske dypbergarter i lia vest for Bjertnessjøen. Den består av en tilnærmet fullstendig gjengrodd dagskjæring og innerst i denne sees kun svart hornfels i veggen som er opptil 6 m høy. Fin- til grovkornet sinkblende finnes disseminert og i semimassive årer og linser i pyroksenskarn i blokker på tippen som har et volum på ca. 70 kbm.

Bibliography:

From NGU's Reference Archive:

Olerud, Svein , 1984

	Metallogeny of the Elsjø area, northern Oslo Region, Norway.

;Norsk geologisk forening;TIDSSKRIFTARTIKKEL;Norsk geologisk tidsskrift; No.64 (4);325-334 pages

Abstract:

The Elsjø area is situated in the northern part of the Oslo Region and consists of a 2 km² inlier of Palaeozoic metasediments. Cambro-Ordovician shales and limestones are enclosed in Permian intrusives and are contact metamorphosed and altered by metasomatic processes. The present investigation has defined three mineralisation types of interest: The heavy-metal content of the Alum shale, sphalerite-bearing skarn lenses within the Alum shale and molybdenite mineralisation in the underlying Permian granites. The Alum shale of the Elsjø area has a maximum thickness of more than 150 metres as a result of overthrusting and folding during the Caledonian orogeny. The highest heavy-metal content is in Upper Cambrian strata. The greatest average content is in 10.6 m thick layer with 160 ppm U, 200 ppm Mo, 930 ppm V, 11.6 % C and 2.8 % S. The Alum shale also contains lenses of hedenbergite-garnet skarn lenses with sphalerite mineralisation; these are alteration products of marble lenses in the shale. Similar sphalerite-bearing skarn mineralisation is also found in other stratigraphic levels on shear zones. The Palaeozoic sedimentary rocks are underlain by three types of Permian granites. Molybdenite occurs as scattered disseminations in the phyllic alteration zones of the granite. Propylitic alteration is common in both the underlying intrusives and in the Palaeozoic sediments. The molybdenite mineralisation has similarities with porphyry molybdenum type occurrences, but can also be interpreted as a roof zone mineralisation in the granites.

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	JS-OS2148	Dump	Sampler :Sandstad/Mansur/...Stored :Løkken/...Size(kg) :2 Kommentar :Semi-massiv sinkblende linser/disseminasjon i grønn skarn No. of registrated element analyses = 1

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

Navn på locality : Knepphauglia sør

(Objekt Id : 0238,010,01,00)

---

Lokalisering

Fylke :

Akershus (02)

Kommune :

Nannestad (0238)

Kart 1:50000:

Nannestad (1915-3)

Kart 1:250000:

Hamar

Markeringspunkt:

Lengdegrad:

10.8675840

Breddegrad:

60.1923260

EU89-UTM Zone 32

(Coordinates IS confirmed)

X-koord:

603555 m.

Y-koord:

6674295 m.

Materialtype

	Hovedtype:	Basemetaller (Cu,Zn,Pb,Fe sulfider,As,Sb,Bi,Sn)	Subtype:	Sink
			Element(s):	Zn

Production

	Activity:	Røsking	Reserves:
	Prod. method:		Production:
	Prod. status:		Volume of dump:	60 m3

Mineralogy

	Relationship	Mineral	Amount
	Gangue mineral	Pyroxene	Major mineral (>10%)
	Gangue mineral	Calcite	Subordinate mineral (1-10%)
	Ore mineral	Sphalerite	Major mineral (>10%)
	Ore mineral	Pyrite	Subordinate mineral (1-10%)
	Ore mineral	Pyrrhotite	Subordinate mineral (1-10%)

Lithology:

	Relationship	Rock	Origin
	Host rock	Hedenbergittskarn	Sedimentary Original rock :Limestone
			Metamorphic facies :Contact
	Wall rock	Hornfels	Sedimentary Original rock :Argillaceous sediment
			Metamorphic facies :Contact

Opplysning(er) i fritekstformat

Fri tekst

Forekomsten består av en 10 m lang og 2-3 m bred dagkjæring med retning 235° og har en 3 m høy vegg i SV. I skjerpet finnes svart hornfels, grafitt-granatskarn (gravhola), svartskifer og kalkstein i veksling, men det er lite sulfidmineralisering. Sinkblende årer i pyroksenskarn og massiv magnetkis med spredte korn av svovelkis finnes i blokker på tippen som har et volum på ca. 60 kbm.

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	JS-OS2146	Dump	Sampler :Sandstad/Mansur/...Stored :Løkken/...Size(kg) :2 Kommentar :Sinkblende åre i skarn med svovelkis disseminasjon No. of registrated element analyses = 1
	JS-OS2147	Dump	Sampler :Sandstad/Mansur/...Stored :Løkken/...Size(kg) :2 Kommentar :Massiv magnetkis med disseminasjon av svovelkis+kobberkis No. of registrated element analyses = 1

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

---

Analyse Results

from

Forekomstområde 238 - 010 Knepphauglia

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#
JS-OS2146	Dump	573	14300	27	82	364	1.2	10.0
JS-OS2147	Dump	765	28100	36	112	453	1.9	13.0
JS-OS2148	Dump	329	87900	16	27	54	2.5	6.0

------------------

Sample No.	Pt#	Pd#	As*	Cd*	Ba*	Mo*	Sn*	Sb*	Bi*
JS-OS2146	-2.5	14.0	8	113.5	30	55.40	2	0	1
JS-OS2147	-2.5	11.0	10	246.0	60	88.70	2	0	2
JS-OS2148	5.0	9.0	7	375.0	10	124.00	4	0	51

------------------

Sample No.	Se*	Ga*	Ge*	In*	S%	V*	Cr*	Mn*	Fe%
JS-OS2146	12.00	8.73	0.33	12.40	9.99	240	15	1385	22.10
JS-OS2147	16.00	9.35	0.27	28.50	9.99	200	12	1310	20.80
JS-OS2148	11.00	10.10	0.18	4.97	6.40	275	23	19150	12.50

------------------

Sample No.	Th*	W*	Rb*	Sr*	Y*	Zr*	Nb*	Ta*	Cs*
JS-OS2146	2.88	2	5.5	28.1	42.0	18	2.00	0.12	0.09
JS-OS2147	2.10	3	10.9	24.8	22.6	26	2.90	0.19	0.10
JS-OS2148	4.63	1	3.4	115.0	27.6	42	4.90	0.32	0.17

------------------

Sample No.	La*	Ce*	Li*	Be*	Na*	Mg*	Al*	P*	K *
JS-OS2146	157.50	207.00	43	4	3800	4100	13000	2190	1500
JS-OS2147	89.10	103.50	21	2	2400	2200	9700	1390	2700
JS-OS2148	41.50	68.70	49	8	1600	11800	23000	4510	500

------------------

Sample No.	Ca*	Sc*	Ti*	Te*	Hf*	Re*	Tl*
JS-OS2146	23000	3.70	510	20.10	0.50	0	0
JS-OS2147	16100	2.50	710	24.30	0.70	0	0
JS-OS2148	######	4.40	1400	4.51	1.10	0	0

---

Faktaarket ble generert 10.06.2026

Spørsmål eller kommentarer vedrørende faktaarket kan mailes til: ressursdatabaser@ngu.no

Copyright © 2026 Norges geologiske undersøkelse