Fact Sheet for <b>Occurence 1824

					Norsk versjon
	THE ORE DATABASE
	Occurence 1824 - 011 Skravlåga
	(Object Id: 2810) (Last updated: 28.04.2020)

Location

County:

Nordland

Municipality:

Vefsn (1824)

Map 1:50000:

Elsfjord (1927-3)

Map 1:250000:

Mo i Rana

Coordinate system:

EU89-UTM Zone 33

East:

430642 m.

North:

7333633 m.

Longitude:

13.4647700

Latitude:

66.1154930

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Resource

	Resource Type:	Ferrous metals(Fe, Mn, Ti)	Resource Subtype:	Iron
			Element(s):	Fe

Importance

Raw material meaning:

Little Importance (reg. 18.02.2015)

Resources and production

	Activity:	Exploration	Reserves:	6510 thousand tons
	Operating method:		Historical production:

Products

Element/product Crude ore grade or quality Reg. date

Fe-mag. 12 % 06.01.1993

Fe-total 25 % 06.01.1993

Operations

From - To Activity Comments

1974 - 1975 Geology Company/Institution :Rana Gruber

1976 - 1976 Geophysics Company/Institution :Rana Gruber

Mineralization

Era: Proterozoic Period: Neoproterozoic

Genesis: Sedex Form: Layer

Main texture: Banded Min. distribution: Semi-massive (20-50 % ore minerals)

Main grain size: Fine grained (< 1 mm) Main alteration:

Strike/Dip: 35 / 80 Direction: 50

Plunge: 18

Stratigraphic classification of host rock

Era: Proterozoic Period: Neoproterozoic

Province: Caledonides

Geotec.unit: Helgeland Nappe Complex

Tectonic complex: Elsfjord unit

Igneous complex:

Group: Elsfjord-gruppen Formation:

Mineralogy

Relationship Mineral Amount

Gangue mineral Amphibole Major mineral (>10%)

Gangue mineral Quartz Major mineral (>10%)

Gangue mineral Epidote Major mineral (>10%)

Gangue mineral Carbonate Subordinate mineral (1-10%)

Gangue mineral Apatite Accessory mineral (<1%)

Ore mineral Magnetite Major mineral (>10%)

Ore mineral Hematite Subordinate mineral (1-10%)

Lithology:

Relationship Rock Origin

Unknown Karb.-aktinolittba. Extrusive
Original rock :Basalt

Metamorphic facies :Amphibolite

Unknown Amfibolitt Extrusive
Original rock :Basalt

Metamorphic facies :Amphibolite

Structures

Location: Type: Orientation(360 gr.): Relation to min.:

Unknown Primary layering Strike/Dip :50 / 80 Syn-mineralisation ;...Effect :None

Information(s) in free text format

Free text

The rock sequence with iron formation at Skravlåga is well exposted along the river beds (WGS84 UTM 33N, 430400/7333850-430750/7333500). In the eastern part of the studied NW-SE trending river section occurs staurolite-bearing garnet-mica schist with consistent foliation and dip; 35°/85°. The schist is crosscut by tonalitic to granitic dykes/veins. Then follows an about 45 m thick unit of iron formation (susceptibility > 10,000 x 10-5 SI units). The IF is fine grained and commonly finely banded with both hematite and magnetite rich bands in few mm- to few cm-scale, and the matrix comprises mainly calcareous amphibole-epidote rock. Three samples were collected (Samples JS_FE 1704-06); from the hanging-wall, foot-wall and central part of the sequence, that represents the main locality for the deposit. No enrichment of Mn was observed. The IF is tectonostratgraphically underlain (up-river) by a nearly 300 m thick sequence of amphibole-mica-bearing calcareous schist. A few elongated lenses/clasts of dolomite is seen in this unit in the eastern 100 m of the sequence. Then occurs an about 50 m thick part with numerous dolomite clasts and the unit resembles diamictite. It is best exposed on the downside of a relatively recent constructed dam. A faint layering with layers in m-scale with various proportion of clasts exists. The clasts are generally strongly elongated and deformed. They are up to 1.5 m long and 10-20 cm thick and occur in a matrix of carbonate, amphibole and mica. An up to 30 cm thick lens of nearly massive, fine grained magnetite mineralisation in amphibole dominated matrix is observed within the diamictite as well as folded magnetite-rich bands in cm-scale (Sample JS_FE1708). Garnet-mica schist occurs in the western part of the section.

Fieldsamples

Sample No. Sample type Miscellanrous

JS_FE1704 Bedrock

Sampler: J.S. Sandstad

Comment: Hematite+magnetite ore, massive

No. of registrated element analyses = 1

No. of registrated oxide analyses = 1

JS_FE1705 Bedrock

Sampler: J.S. Sandstad

Comment: Magnetite-hematite, banded, calc-epidote-biotite-amphibole matrix

No. of registrated element analyses = 1

No. of registrated oxide analyses = 1

JS_FE1706 Bedrock

Sampler: J.S. Sandstad

Comment: Magnetite-hematite, banded, calc-biotite-amphibole matrix

No. of registrated element analyses = 1

No. of registrated oxide analyses = 1

NO0698.01 Bedrock

Sampler: Wilberg, R./...Stored: Løkken

Comment: Fink., båndet mt-hm-malm, gjennomsnittsprøve.

No. of registrated element analyses = 1

NO0698.02 Bedrock

Sampler: Wilberg, R./...Stored: Løkken

Comment: Båndet hm-min. i amfibolitt.

No. of registrated element analyses = 1

NO0698.03 Bedrock

Sampler: Wilberg, R./...Stored: Løkken

Comment: Semimassiv mt-hm i amf.

No. of registrated element analyses = 1

NO0698.04 Bedrock

Sampler: Wilberg, R./...Stored: Løkken

Comment: Massiv mt-malm.

No. of registrated element analyses = 1

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

Name of Sample point: Skravlåga dam

(Object Id: 36440 11,00,01)

Location

County: Nordland Municipality: Vefsn (1824)

Map 1:50000: Elsfjord (1927-3) Map 1:250000: Mo i Rana

Coordinate system: EU89-UTM Zone 33

East: 430516 m. North: 7333741 m.

Longitude: 13.4619420 Latitude: 66.1164360

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Resource

Resource Type: Ferrous metals(Fe, Mn, Ti) Resource Subtype: Iron

Element(s): Fe

Information(s) in free text format

Free text

Just east of the dam in Skravlåga occurs an about 50 m thick unit that resembles diamictite with numerous dolomite clasts. It is best exposed on the downside of the relatively recent constructed dam. A faint layering with layers in m-scale with various proportion of clasts exists. The clasts are generally strongly elongated and deformed. They are up to 1.5 m long and 10-20 cm thick and occur in a matrix of carbonate, amphibole and mica. An up to 30 cm thick lens of nearly massive, fine grained magnetite mineralisation in amphibole dominated matrix is observed within the diamictite as well as folded magnetite-rich bands in cm-scale (Sample JS_FE1708).

Fieldsamples

Sample No. Sample type Miscellanrous

JS_FE1708 Bedrock

Sampler: J.S. Sandstad

Comment: Magnetite, massive, fine grained in amphibole matrix

No. of registrated element analyses = 1

No. of registrated oxide analyses = 1

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

Analyse Results

from

Deposit Area 1824 - 011 Skravlåga

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_FE1704 Bedrock 3 27 1 15 15 1.7

JS_FE1705 Bedrock 2 24 1 10 11 1.5

JS_FE1706 Bedrock 5 13 1 9 12 -.5

JS_FE1708 Bedrock 7 22 1 6 12 .8

NO0698.01 Bedrock 28 17 -3 3 17 -.3 6.0

NO0698.02 Bedrock 6 15 -3 1 8 -.3 -2.0

NO0698.03 Bedrock 11 13 3 3 13 -.3 5.0

NO0698.04 Bedrock 24 10 6 1 12 -.3 -2.0

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

Sample No. Pt# Pd# Rh# As* Cd* Ba* Mo* Sn* Sb*

JS_FE1704 2 616 0.70 1

JS_FE1705 1 374 0.50 -1

JS_FE1706 1 151 0.60 -1

JS_FE1708 -1 207 0.80 1

NO0698.01 -3.0 -3.0 -5.0 -2 .5 17 3.00 -2

NO0698.02 -3.0 -3.0 -5.0 3 .4 14 1.00 -2

NO0698.03 -3.0 -3.0 -5.0 4 1.6 8 1.00 4

NO0698.04 -3.0 -3.0 -5.0 2 2.1 17 -1.00 -2

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

Sample No. Bi* Se* Ga* S% V* Cr* Mn* Fe% Th*

JS_FE1704 -0.50 8.10 116 3.90

JS_FE1705 -0.50 6.20 82 2.50

JS_FE1706 -0.50 5.10 66 2.90

JS_FE1708 3.30 7.80 92 4.30

NO0698.01 13 -.01 40 24 707 14.74 2.00

NO0698.02 3 -.01 35 23 610 7.10 3.00

NO0698.03 23 -.01 37 17 549 26.76 2.00

NO0698.04 29 -.01 56 46 595 32.60 3.00

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

Sample No. U* W* Rb* Sr* Y* Zr* Nb* Ta* Cs*

JS_FE1704 1.00 -1 50.6 357.5 24.1 83 6.90 0.40 2.40

JS_FE1705 0.60 1 47.1 200.8 19.8 68 5.10 0.30 2.10

JS_FE1706 0.60 1 23.1 375.9 21.4 67 6.30 0.40 0.40

JS_FE1708 1.10 -1 22.1 289.4 30.5 108 7.50 0.50 1.60

NO0698.01 -5.00 -2 72.0

NO0698.02 -5.00 -2 74.0

NO0698.03 -5.00 -2 12.0

NO0698.04 -5.00 -2 35.0

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

Sample No. La* Ce* Pr* Nd* Sm* Eu* Gd* Tb* Dy*

JS_FE1704 29.90 67.00 7.78 32.70 6.07 1.31 5.74 0.86 5.03

JS_FE1705 15.70 32.90 4.01 16.40 3.11 0.71 3.12 0.49 3.25

JS_FE1706 16.80 34.20 4.01 15.30 3.06 0.79 3.34 0.54 3.39

JS_FE1708 22.60 45.40 5.62 23.30 4.22 0.94 4.39 0.71 4.40

NO0698.01 6.00

NO0698.02 10.00

NO0698.03 4.00

NO0698.04 5.00

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

Sample No. Ho* Er* Tm* Yb* Lu* B* Be* Hf*

JS_FE1704 0.93 2.80 0.39 2.41 0.37 -1 2.10

JS_FE1705 0.65 2.12 0.29 2.02 0.32 1 1.40

JS_FE1706 0.72 2.20 0.33 2.07 0.35 -1 1.70

JS_FE1708 0.96 2.95 0.43 2.85 0.45 -1 2.80

NO0698.01 -3

NO0698.02 -3

NO0698.03 -3

NO0698.04 -3

Oxide analyses
( All values are in % )

Sample No. Sample Type SiO2 Al2O3 TiO2 Fe2O3 MnO MgO CaO

JS_FE1704 Bedrock 18.20 4.53 0.42 68.40 0.59 2.35 3.42

JS_FE1705 Bedrock 33.00 4.47 0.31 51.20 0.15 3.90 4.64

JS_FE1706 Bedrock 39.10 4.47 0.38 37.30 0.39 3.09 9.76

JS_FE1708 Bedrock 42.90 6.47 0.60 35.80 0.01 3.21 6.58

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

Sample No. Na2O K2O P2O5 Loss Sum

JS_FE1704 0.86 1.24 0.92 -1.33 100.00

JS_FE1705 0.59 1.36 0.40 -0.89 99.00

JS_FE1706 0.61 0.61 0.52 2.67 99.00

JS_FE1708 1.16 0.76 0.97 0.54 99.00

Element/product	Crude ore grade or quality	Reg. date
Fe-mag.	12 %	06.01.1993
Fe-total	25 %	06.01.1993

From - To	Activity	Comments
1974 - 1975	Geology	Company/Institution :Rana Gruber
1976 - 1976	Geophysics	Company/Institution :Rana Gruber

Era:	Proterozoic	Period:	Neoproterozoic
Genesis:	Sedex	Form:	Layer
Main texture:	Banded	Min. distribution:	Semi-massive (20-50 % ore minerals)

	Province:	Caledonides
	Geotec.unit:	Helgeland Nappe Complex
	Tectonic complex:	Elsfjord unit
	Igneous complex:

Relationship	Mineral	Amount
Gangue mineral	Amphibole	Major mineral (>10%)
Gangue mineral	Quartz	Major mineral (>10%)
Gangue mineral	Epidote	Major mineral (>10%)
Gangue mineral	Carbonate	Subordinate mineral (1-10%)
Gangue mineral	Apatite	Accessory mineral (<1%)
Ore mineral	Magnetite	Major mineral (>10%)
Ore mineral	Hematite	Subordinate mineral (1-10%)

Relationship	Rock	Origin
Unknown	Karb.-aktinolittba.	Extrusive Original rock :Basalt
		Metamorphic facies :Amphibolite
Unknown	Amfibolitt	Extrusive Original rock :Basalt
		Metamorphic facies :Amphibolite

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Unknown	Primary layering	Strike/Dip :50 / 80	Syn-mineralisation ;...Effect :None

Sample No.	Sample Type	Cu*	Zn*	Pb*	Co*	Ni*	Ag*	Au#
JS_FE1704	Bedrock	3	27	1	15	15		1.7
JS_FE1705	Bedrock	2	24	1	10	11		1.5
JS_FE1706	Bedrock	5	13	1	9	12		-.5
JS_FE1708	Bedrock	7	22	1	6	12		.8
NO0698.01	Bedrock	28	17	-3	3	17	-.3	6.0
NO0698.02	Bedrock	6	15	-3	1	8	-.3	-2.0
NO0698.03	Bedrock	11	13	3	3	13	-.3	5.0
NO0698.04	Bedrock	24	10	6	1	12	-.3	-2.0

Sample No.	Pt#	Pd#	Rh#	As*	Cd*	Ba*	Mo*	Sn*	Sb*
JS_FE1704				2		616	0.70	1
JS_FE1705				1		374	0.50	-1
JS_FE1706				1		151	0.60	-1
JS_FE1708				-1		207	0.80	1
NO0698.01	-3.0	-3.0	-5.0	-2	.5	17	3.00		-2
NO0698.02	-3.0	-3.0	-5.0	3	.4	14	1.00		-2
NO0698.03	-3.0	-3.0	-5.0	4	1.6	8	1.00		4
NO0698.04	-3.0	-3.0	-5.0	2	2.1	17	-1.00		-2

Sample No.	Bi*	Se*	Ga*	S%	V*	Cr*	Mn*	Fe%	Th*
JS_FE1704		-0.50	8.10		116				3.90
JS_FE1705		-0.50	6.20		82				2.50
JS_FE1706		-0.50	5.10		66				2.90
JS_FE1708		3.30	7.80		92				4.30
NO0698.01	13			-.01	40	24	707	14.74	2.00
NO0698.02	3			-.01	35	23	610	7.10	3.00
NO0698.03	23			-.01	37	17	549	26.76	2.00
NO0698.04	29			-.01	56	46	595	32.60	3.00

Sample No.	La*	Ce*	Pr*	Nd*	Sm*	Eu*	Gd*	Tb*	Dy*
JS_FE1704	29.90	67.00	7.78	32.70	6.07	1.31	5.74	0.86	5.03
JS_FE1705	15.70	32.90	4.01	16.40	3.11	0.71	3.12	0.49	3.25
JS_FE1706	16.80	34.20	4.01	15.30	3.06	0.79	3.34	0.54	3.39
JS_FE1708	22.60	45.40	5.62	23.30	4.22	0.94	4.39	0.71	4.40
NO0698.01	6.00
NO0698.02	10.00
NO0698.03	4.00
NO0698.04	5.00

Sample No.	Ho*	Er*	Tm*	Yb*	Lu*	B*	Be*	Hf*
JS_FE1704	0.93	2.80	0.39	2.41	0.37		-1	2.10
JS_FE1705	0.65	2.12	0.29	2.02	0.32		1	1.40
JS_FE1706	0.72	2.20	0.33	2.07	0.35		-1	1.70
JS_FE1708	0.96	2.95	0.43	2.85	0.45		-1	2.80
NO0698.01						-3
NO0698.02						-3
NO0698.03						-3
NO0698.04						-3

Sample No.	Sample Type	SiO2	Al2O3	TiO2	Fe2O3	MnO	MgO	CaO
JS_FE1704	Bedrock	18.20	4.53	0.42	68.40	0.59	2.35	3.42
JS_FE1705	Bedrock	33.00	4.47	0.31	51.20	0.15	3.90	4.64
JS_FE1706	Bedrock	39.10	4.47	0.38	37.30	0.39	3.09	9.76
JS_FE1708	Bedrock	42.90	6.47	0.60	35.80	0.01	3.21	6.58

Sample No.	Na2O	K2O	P2O5	Loss	Sum
JS_FE1704	0.86	1.24	0.92	-1.33	100.00
JS_FE1705	0.59	1.36	0.40	-0.89	99.00
JS_FE1706	0.61	0.61	0.52	2.67	99.00
JS_FE1708	1.16	0.76	0.97	0.54	99.00