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	THE ORE DATABASE
	Deposit Area 1849 - 009
	(Last updated 23.okt.2024)

Importance

Public:

(No data)

Economical:

Not classified/evaluated

Mineralization

	Era:		Period:
	Dating:		Method:
	Genesis:		Form:
	Main texture:		Min. distribution:

Main grain size:

Main alteration:

	Strike/Dip:		Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Period:

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	Geotec.unit:
	Tectonic complex:
	Igneous complex:

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Formation:

Information(s) in free text format

Free text

Mûller (2011) gives the folloing description Romer et al. (1992) provided a geochemical data set from the Hellemobotn granite gneisses. Four of the analyses showed unusually high REE-Th-U concentrations (Müller 2010). The samples originated from Amásvágge, ca. 4 km SE of Hellemobotn and were collected by A. Korneliussen and T. Grenne (NGU) in 1988. Figure 30 shows the route and sampling locations of the author following the route of Korneliussen and Grenne. The area is characterised by a high variability of gneiss textures including fine-, medium- and coarsegrained and porphyritic varieties. The background gamma-ray intensity is relatively high for all granite varieties, ranging from 500 to 900 cps. The gamma-ray anomaly was identified at 33V 566560/7520281 (sample 25091004) exactly at the site where A. Korneliussen and T. Grenne took the samples with high REE concentrations (Fig. 30b). The mineralised granite gneiss forms a NNW-striking, dyke-like structure which is 30 m wide. Due to the limited time the dyke could be followed for 300 m but it is presumably much longer. The mineralisation comprises et least 600 000 t assuming a minimum length of 300 m, a width of 30 m and a vertical extension of about 25 m. The ground-measured anomaly coincides with a small airborne-measured Th-radiation anomaly (Fig. 31). The anomaly lies on a NNW-NW striking structure which extends from the Swedish border to Vuodnabattjåhkkå, interrupted by the Ávttje canyon (Fig. 31). Three samples (25091001 to -03) were collected from the high gamma-radiation area (>1000 cps) which forms a dyke-like structure consisting of medium-grained biotite granite gneiss. In addition, four different textural types of granite gneiss (samples 25091004 to -07) with gamma-ray signals from 500 - 900 cps were sampled (Fig. 30b). The highly radioactive samples contain 0.085 to 0.203 wt.% REO+Y2O3, the highest values reported in this project (Fig. 23). Zr concentrations range from 443 to 909 ppm, Th from 91 to 138 ppm and U from 20 to 33 ppm. The concentrations of the less radioactive granite gneisses are 0.018 to 0.038 wt.% REO+Y2O3, 185 to 383 ppm Zr, 23 to 70 ppm Th, 4 to 18 ppm U. In the case of the Hellemobotn granite gneisses, the gamma-ray radiation intensity correlates with REE-Th-U content. The highly radioactive samples are enriched in LREE and HREE compared to average granite (Fig. 32). Titanite is the most common accessory mineral in the highly radioactive samples, with grain sizes of 40 to 2000 µm (Fig. 33; Table 1). The REE concentrations of titanite are low, <1%, but it is, nevertheless, considered as an important carrier of the LREE because of the its high abundance. Th-rich allanite occurs as inclusions in titanite and it seems that titanite replaced allanite (Fig. 33a). Allanite is the major accessory mineral in the less radioactive samples. Other common accessories are zircon (20-160 µm), apatite (20-60 µm) and magnetite (40-1000 µm). Less common accessories are fluorite (20-200 µm), polycrase-(Y) (5-10 mm) and thorianite (5-10 µm). Sample 25091006 contains large ilmenite crystals with exsolution structures.

Bibliography:

From NGU's Reference Archive:

Müller, Axel , 2011

	Potential of rare earth element and Zr-, Be, U-, Th-, (W-) mineralisations in central and northern Nordland - Part 2

;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.2011.021;56 pages

Abstract:

In this report results of the investigation of potential rare earth elements (REE) and Zr-, Be, U-, Th-, (W-) mineralisations in central and northern Nordland are presented. The investigated and sampled mineralisations were proposed in NGU report 2009.037 on the basis if existing reports and geochemical data sets. The investigation targets were evolved Proterozoic TIB-type granites (TIB = Trans-Scandinavian Igneous Belt) of the Tysfjord, Sommerset and Rishaugfjell basement windows, in particular, the Hatten- Tilthornet massif, Hundholmen, Kjerrfjellet, Hellemobotn, Reinoksskardet, upper Gjerdalen areas, the Sommerset basement Window, Rismålsvatn, and Memaurvatn. The general aim was to identify Zr-Ree mineralisations with >= 2wt.% REO (including Y2O3; REO - rare earth oxides) which are possibly enriched in Be, U and Th as well.

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	25091001	Bedrock	Sampler :Axel M¿ller Comment :medium-grained biotite granite gneiss, mineralised, UTM east 566519, UTM north 7520464 No. of registrated element analyses = 1 No. of registrated oxide analyses = 1
	25091002	Bedrock	Sampler :Axel M¿ller Comment :medium-grained biotite-rich granite gneiss, mineralised, UTM east 566519, UTM north 7520464 No. of registrated element analyses = 1 No. of registrated oxide analyses = 1
	25091003	Bedrock	Sampler :Axel M¿ller Comment :medium-grained biotite granite gneiss, mineralised, UTM east 566560, UTM north 7520281 No. of registrated element analyses = 1 No. of registrated oxide analyses = 1
	25091004	Bedrock	Sampler :Axel M¿ller Comment :medium-grained biotite granite gneiss, non-mineralised, UTM east 565950, UTM north 7519621 No. of registrated element analyses = 1 No. of registrated oxide analyses = 1
	25091005	Bedrock	Sampler :Axel M¿ller Comment :fine-grained porphyritic biotite gneiss, non-mineralised, UTM east 565552, UTM north 7519525 No. of registrated element analyses = 1 No. of registrated oxide analyses = 1
	25091006	Bedrock	Sampler :Axel M¿ller Comment :medium-grained biotite granite gneiss, non-mineralised, UTM east 565312, UTM north 7519485 No. of registrated element analyses = 1 No. of registrated oxide analyses = 1
	25091007	Bedrock	Sampler :Axel M¿ller Comment :medium-grained biotite granite gneiss, non-mineralised, UTM east 565023, UTM north 7519733 No. of registrated element analyses = 1 No. of registrated oxide analyses = 1

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

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Analyse Results

from

Deposit Area 1849 - 009 Hellemobotn

Element analyses

( *=parts pr. million, #=parts pr.billion, Negative values means below detection limit value.)

Sample No.	Sample Type	Cu*	Zn*	Pb*	Co*	Ni*	Au#	As*
25091001	Bedrock	-0	86	9	3	0	-.5	1
25091002	Bedrock	0	103	11	4	1	-.5	2
25091003	Bedrock	0	143	10	5	1	-.5	2
25091004	Bedrock	0	51	7	2	0	-.5	1
25091005	Bedrock	1	43	4	3	1	-.5	1
25091006	Bedrock	0	15	4	3	1	-.5	-1
25091007	Bedrock	3	27	8	1	0	-.5	-1

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Sample No.	Cd*	Ba*	Mo*	Sn*	Sb*	Bi*	Se*	Ga*	V*
25091001	-.1	246	0.70	4	-0	-0	-0.50	25.20	8
25091002	-.1	190	1.50	5	-0	-0	-0.50	26.20	12
25091003	-.1	166	1.60	8	-0	-0	-0.50	27.20	16
25091004	-.1	229	3.20	2	-0	-0	-0.50	22.20	-8
25091005	-.1	756	2.60	2	-0	-0	-0.50	21.00	21
25091006	-.1	137	-0.10	4	-0	0	-0.50	21.50	-8
25091007	-.1	186	0.10	3	-0	-0	-0.50	20.80	-8

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Sample No.	Th*	U*	W*	Rb*	Sr*	Y*	Zr*	Nb*	Cs*
25091001	90.80	20.20	-1	292.5	80.6	51.0	443	30.20	3.10
25091002	121.80	29.30	1	261.4	78.3	93.1	684	42.10	3.10
25091003	137.70	33.40	-1	299.1	63.0	117.5	910	59.90	4.80
25091004	70.00	17.60	1	288.4	70.0	38.3	311	21.60	2.30
25091005	23.10	3.80	-1	229.9	154.0	24.2	383	19.40	1.30
25091006	62.60	13.60	1	270.0	89.7	29.3	185	23.50	0.90
25091007	58.20	15.80	-1	303.5	48.7	36.7	210	22.40	1.30

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Sample No.	La*	Ce*	Pr*	Nd*	Sm*	Eu*	Gd*	Tb*	Dy*
25091001	161.10	332.50	31.21	99.30	14.58	0.60	9.83	1.58	9.25
25091002	322.50	640.50	58.08	189.00	25.68	0.77	18.17	2.82	15.77
25091003	398.80	791.40	72.96	233.20	31.88	0.76	22.50	3.64	19.83
25091004	121.60	259.00	24.58	80.10	12.01	0.62	7.75	1.24	6.71
25091005	69.10	161.70	15.52	52.00	8.03	0.80	5.50	0.84	4.40
25091006	26.90	71.70	6.03	19.50	3.34	0.20	2.62	0.57	3.75
25091007	60.80	133.00	12.54	40.90	6.89	0.33	5.44	0.95	5.57

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Sample No.	Ho*	Er*	Tm*	Yb*	Lu*	Be*	Hf*	Hg*	Tl*
25091001	1.68	5.05	0.76	5.14	0.77	7	12.40	-0	1
25091002	2.97	8.60	1.29	8.32	1.26	6	18.70	-0	1
25091003	3.89	11.48	1.75	11.34	1.72	7	26.30	-0	2
25091004	1.22	3.64	0.55	3.54	0.52	5	10.30	-0	1
25091005	0.82	2.28	0.33	2.12	0.32	4	10.00	-0	1
25091006	0.89	2.93	0.49	3.21	0.47	5	7.40	-0	0
25091007	1.13	3.55	0.59	4.04	0.62	5	7.30	-0	0

Oxide analyses

( All values are in % )

Sample No.	Sample Type	SiO2	Al2O3	TiO2	Fe2O3	MnO	MgO	CaO
25091001	Bedrock	69.29	14.77	0.41	3.42	0.06	0.43	1.20
25091002	Bedrock	69.39	13.51	0.55	4.92	0.09	0.65	1.47
25091003	Bedrock	68.86	12.61	0.76	6.43	0.11	0.72	1.75
25091004	Bedrock	71.82	14.58	0.24	2.26	0.04	0.32	0.88
25091005	Bedrock	70.92	14.05	0.37	2.78	0.04	0.37	1.28
25091006	Bedrock	76.12	12.56	0.15	1.44	0.02	0.24	0.48
25091007	Bedrock	74.97	12.70	0.18	1.81	0.04	0.17	0.80

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Sample No.	Na2O	K2O	P2O5	Loss	Sum
25091001	4.05	5.42	0.07	0.70	100.00
25091002	3.84	4.33	0.10	0.80	100.00
25091003	3.53	3.89	0.15	0.80	100.00
25091004	4.12	5.27	0.04	0.30	100.00
25091005	3.66	5.51	0.08	0.80	100.00
25091006	3.65	4.77	0.03	0.50	100.00
25091007	3.52	5.30	0.04	0.40	100.00

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The fact sheet was created on 22.11.2024

Questions or comments regarding the fact sheet can be emailed to: ressursdatabaser@ngu.no

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