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	MALMDATABASEN
	Forekomstområde 1845 - 013
	(Sist oppdatert 23.okt.2024)

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Kan være viktig , (Stadfestet 22.okt.2024 av Havard Gautneb)

Mineralisering

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Stratigrafisk klassifikasjon av vertsbergart

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Müller 2011 refport the following regarding the Memaurvann occurrence The reason for sampling the granite gneiss of the northern Rishaugfjell window was one Uranal database analysis of a TIB-granite sample from Memaurvatn (UTM 33W 529233E/7472096N) which contained 11700 ppm Zr and 884 ppm Y+La+Ce. During the field campaign two areas of coarse-grained biotite granite gneiss (ca. 130 x 30 m and 150 x 5 m) with high gamma radiation (>1000 cps) were identified south of the lake Memaurvatn The estimated resource is about 300 000 tons assuming a vertical extension of the mineralisation of 25 m. The mineralised granite gneiss contains aggregates of fine-grained violet fluorite with crystal sizes of up to 1 mm. The gamma radiation of the nonmineralised, fluorite-free host granite gneiss is about 480 cps. Three samples were collected: two mineralized coarse-grained biotite granite gneisses (samples 22091002 and 22091003) and one non-mineralised coarse-grained biotite granite gneiss (sample 22091001). All three samples have REO concentrations of 0.064 to 0.070 wt.% REO (Fig. 8). Sample 22091001 is characterized by high Zr - 1658 ppm and high U - 134 ppm (Appendix 2). The REE distribution pattern indicates that LREE and HREE are enriched in samples 22091001 and 22091002 compared to average granite composition according to Turekian and Wedepohl (1961) (Fig. 9). In addition, the Memaurvatn granite gneiss is characterized by a strong Eu anomaly indicating a strong fractional crystallization. The fluorite-bearing sample 22091003 is slightly depleted in HREE. It is assumed, that the fluorite-forming fluids caused the HREE depletion in sample 22091003. Thus, high gammaray signals measured with the scintillometer in the field do not necessarily detect all rocks with elevated REE-Zr concentrations. SEM investigations revealed that allanite and zircon are the most common accessory REE-bearing minerals (Fig. 10, Table 1). Fluorite is particularly common in sample 22091003 but it contains <1 % REE. Apatite, monazite or xenotime, which are common accessories in granitic rocks, could not be identified. Allanite crystals are 40 to 120 µm in size and carry most of the LREE. Zircon forms two generations: an older, porous, partially dissolved generation, with grain sizes of 20 to 80 µm and younger, euhedral, homogeneous generations with grain sizes of 5 to 10 µm. Zircon is the major carrier of the HREE. In addition there are some titanite crystals, 10 to 50 µm. In sample 22091003 zircons of generation 1 are most intensely dissolved which explains the depletion of HREE. Titanite can be an important carrier of LREE (e.g. Seifert 2005) but EDX analysis revealed that the REE content of the titanites is <1 wt.%.

Litteraturfortegnelser:

Fra NGU's Referansearkiv.:

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 sider

Abstrakt:

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.

Feltprøver

	Prøvenr.	Prøvetype	Diverse
	22091001	Fastfjell	Prøvetaker :Axel M¿ller Kommentar :coarse-grained biotite granite gneiss, non-mineralised, UTM east 528891, UTM north 7472316 Antall registrerte elementanalyser = 1 Antall registrerte oksydanalyser = 1
	22091002	Fastfjell	Prøvetaker :Axel M¿ller Kommentar :coarse-grained biotite granite gneiss, mineralised, UTM east 529262, UTM north 7472074 Antall registrerte elementanalyser = 1 Antall registrerte oksydanalyser = 1
	22091003	Fastfjell	Prøvetaker :Axel M¿ller Kommentar :coarse-grained biotite granite gneiss with fluorite, mineralised, UTM east 529191, UTM north 7471937 Antall registrerte elementanalyser = 1 Antall registrerte oksydanalyser = 1

NB! Alle analyseverdier er vist i slutten av utskriften.:

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Analyseresultater

fra

Forekomstområde 1845 - 013 Memaurvann

Elementanalyser

( *=parts pr. million, #=parts pr.billion, Negative verdier betyr under deteksjonsgrensen.)

Prøvenr.	Prøvetype	Cu*	Zn*	Pb*	Co*	Ni*	Au#	As*
22091001	Fastfjell	2	67	7	1	1	-.5	6
22091002	Fastfjell	2	89	13	2	4	-.5	4
22091003	Fastfjell	6	37	22	1	1	-.5	10

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Prøvenr.	Cd*	Ba*	Mo*	Sn*	Sb*	Bi*	Se*	Ga*	V*
22091001	-.1	405	0.20	6	1	0	1.20	24.80	-8
22091002	.4	279	0.30	6	0	0	2.20	23.70	-8
22091003	-.1	137	4.50	3	1	0	1.20	24.60	-8

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Prøvenr.	Th*	U*	W*	Rb*	Sr*	Y*	Zr*	Nb*	Cs*
22091001	41.10	12.70	1	286.1	75.9	65.1	541	33.70	3.50
22091002	35.10	134.50	1	292.7	58.8	158.3	1658	28.80	4.70
22091003	61.50	10.10	1	314.3	31.2	30.7	113	18.80	2.90

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Prøvenr.	La*	Ce*	Pr*	Nd*	Sm*	Eu*	Gd*	Tb*	Dy*
22091001	107.40	241.80	25.99	94.50	15.81	1.00	12.02	2.11	12.01
22091002	74.20	161.40	17.32	60.30	14.76	0.82	17.34	2.94	18.95
22091003	125.40	268.00	22.52	70.50	9.34	0.44	4.96	0.90	4.89

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Prøvenr.	Ho*	Er*	Tm*	Yb*	Lu*	Be*	Hf*	Hg*	Tl*
22091001	2.39	6.61	0.97	6.47	0.96	8	15.80	-0	1
22091002	4.30	13.05	1.79	11.04	1.59	8	29.90	-0	1
22091003	0.96	2.92	0.46	3.36	0.53	8	4.50	-0	0

Oksydanalyser

(Alle verdier er i %)

Prøvenr.	Prøvetype	SiO2	Al2O3	TiO2	Fe2O3	MnO	MgO	CaO
22091001	Fastfjell	72.06	13.23	0.34	3.39	0.05	0.41	0.80
22091002	Fastfjell	72.56	12.43	0.27	3.93	0.08	0.62	0.58
22091003	Fastfjell	74.60	12.72	0.10	1.66	0.02	0.11	0.75

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Prøvenr.	Na2O	K2O	P2O5	Loss	Sum
22091001	3.37	5.72	0.05	0.40	100.00
22091002	3.03	5.63	0.04	0.50	100.00
22091003	3.39	5.94	0.02	0.60	100.00

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Faktaarket ble generert 22.11.2024

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