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	Registrering 0 - 000 FEIL
	(Objekt Id: ) (Sist oppdatert: 07.03.2017)

Operasjoner

	Fra - Til	Aktivitet	Kommentar
	2007 - 2011	Geokjemi	Selskap/Institusjon:Scandinavian Resources
			Nearly 10000 samples (soil, stream samples).
	2008 - 2008	Geofysikk	Selskap/Institusjon:Scandinavian Resources
			TEM (only profiles) and Magnetometry
	2009 - 2009	Geofysikk	Selskap/Institusjon:Scandinavian Resources
			Ground magnetic survey
	2009 - 2011	Geologi	Selskap/Institusjon:Scandinavian Resources
	2010 - 2010	Kjerneboring	Selskap/Institusjon:Scandinavian Resources
			6 holes totaling 680 m at two localiities.
	2011 - 2011	Geofysikk	Selskap/Institusjon:NGU
			Magnetometry, EM, Radiometry
	2011 - 2013	Geologi	Selskap/Institusjon:NGU

Mineralisering

	Æra:	Proterozoikum	Periode:
	Genese:	Metamorfogen	Form:	Lag
	Hovedtekstur:	Strukturløs	Min. fordeling:	Uregelmessig

Kornstørrelse:

Finkornet (<1 mm)

Hovedomvandling:

Serisittisering

	Strøk/Fall:	120 / 90	Retning:
			Feltstupning:

Stratigrafisk klassifikasjon av vertsbergart

Æra:

Proterozoikum

Periode:

Mesoproterosoikum

	Provins:	Troms-Finnmark grunnfjellsprovins
	Geotek.enhet:
	Tektonisk complex:	Mauken Tectonic Window
	Intrusivt komplex:

Gruppe:

Målselva Group

Formasjon:

Aurevatn Formation

Mineralogi

	Relasjon	Mineral	Mengde
	Gangmineral	Kvarts	Hovedmineral (>10%)
	Gangmineral	Muskovitt	Hovedmineral (>10%)
	Gangmineral	Biotitt	Hovedmineral (>10%)
	Gangmineral	Feltspat	Hovedmineral (>10%)
	Gangmineral	Serisitt	Hovedmineral (>10%)
	Gangmineral	Epidot	Underordnet mineral (1-10%)
	Gangmineral	Turmalin	Aksessorisk mineral (<1%)
	Malmmineral	Magnetkis	Hovedmineral (>10%)
	Malmmineral	Arsenkis	Hovedmineral (>10%)
	Malmmineral	Gull	Aksessorisk mineral (<1%)
	Malmmineral	Kobberkis	Aksessorisk mineral (<1%)

Litologi:

	Relasjon	Bergart	Opprinnelse
	Vertsbergart	Siltstein	Sedimentær
			Metamorf fase :Grønnskifer
	Vertsbergart	Sandstein	Sedimentær
			Metamorf fase :Grønnskifer

Strukturer

	Lokalisering:	Type:	Orientring(360¤):	Relasjon til min.:
	Vertsbergart	Foliasjon	Strøk/Fall :120 / 90	Post-mineralisering ;...Effekt :Modifiserer

Opplysning(er) i fritekstformat

Fri tekst

Scandinavian Highlands (SH) started their prospecting campaign in the Mauken area in 2007 and soon discovered gold anomalies in their stream sediment samples. Further work, including reconnaissance airborne TEM and magnetic surveys, soil sampling, mapping and rock sampling led to the discovery of the so-called "Main Zone", located in sediments close to the contact to the massive greenstone. The company did trenching and chip sampling at several localities along the zone, resulting in that gold values up to 6 g/t were found in a zone 4-6 m wide and over a length of 1800 m (SH press release, 2011). The zone was drilled at two localities in 2010 (total of 6 holes), but the results of the drilling were not promising. No more exploration work has been done by the company on this target since 2010. The mineralization is situated c. 100 m structurally and stratigraphically above the contact to the massive greenstone, in a steep to vertically dipping sequence of interbedded siltstone and sandstone. This sedimentary sequence is 150-200 m thick, and grades upwards into a > 600 m thick layer of rhythmically alternating, silty to more coarse sandstone, possibly a turbiditic sequence. The contact to the structurally underlying greenstone is marked by a 50-100 m layer of calc-brecciated greenstone, which includes thin lenses of calcite marble. The main mineralization is hosted by the more fine-grained siltstone and sandstone, and the maximum thickness is 2.5 m to 2.7 m. Sedimentary structures like cross-bedding and graded bedding are locally present, indicating that the mineralized sequence has right-way-up towards the northeast. The metasediments consist of irregular clastic grains of feldspar and quartz in a very fine-grained matrix of biotite and muscovite. Tourmaline is a common accessory, the boron indicating a seawater environment. The matrix minerals are commonly overgrown by late-stage clinozoisite/epidote and muscovite. Arsenopyrite and pyrrhotite are the main sulfide minerals and occur mainly disseminated, but locally concentrated in thin bands. Chalcopyrite is a common accessory phase, associated with pyrrhotite. Arsenopyrite occurs as hypidioblastic to idioblastic elongated grains, up to several mm in length. It contains inclusions of the other sulfides, and appears to be a later phase than these. The arsenopyrite grains are quite frequently associated with elongate quartz aggregates or lenses, while the hosting sediments commonly show varying degree of sericitization in bands close to the sulfides. Gold occur as small (10-20 microns) inclusions in arsenopyrite. A few small inclusions of gold are found in pyrrhotite and are also present in the silicate matrix. Four samples from the mineralization were analyzed by NGU for a number of elements and show that the mineralization contains only gold (up to 4 ppm Au) and arsenic (up to 0.98 % As), while contents of base metals such as Cu, Zn and Pb are less than a few hundreds of ppm. The "Main Zone" is localized in sand-/siltstone close to the contact to underlying greenstone, and this contact zone may have been important with respect to the formation of the mineralization. The restricted thickness (up to 2.7 m) and extent of the mineralized zone (some 600 m), as well as low grade (only sporadic > 1 ppm gold), is clearly not economic. However, the zone disappears into a swampy area to the southeast and is covered by vegetation to the northwest. One possible source of gold and arsenic in this setting is carbonaceous sediments, which are known to concentrate a number of metals in early formed, diagenetic iron sulfides (Large et al., 2011, Thomas et al., 2011). At Mauken, close to the contact to the underlying greenstone, the siltstone is quite rich in graphite, and also contains minor amounts of iron sulfides. According to a model for orogenic gold deposits presented by Large et al. (2011), gold, arsenic and sulfur are preferentially released from the diagenetic sulfides because of recrystallization during later metamorphism. The resulting fluids may follow structural pathways and deposit the metals higher up in the sequence. In the case of Mauken, the fluids may have been concentrated along or close to the greenstone-sediment contact.

Referanser

Large, R.R., Bull, S.W., Maslennikov, V., 2011: A carbonaceous sedimentary source-rock model for Carlin-type and orogenic gold deposits. Economic Geology, v.106, p.331-358. Thomas, H.V., Large. R.R., Bull, S.W., Maslennikov, V., Berry, R.F., Fraser, R., Froud, S., and Moye, R., 2011: Pyrite and pyrrhotite and composition in sediments, laminated quartz veins, and reefs at Bendigo gold mine, Australia: Insights for ore genesis. Economic Geology, v.106, p.1-32.

Litteraturfortegnelser:

Fra NGU's Referansearkiv.:

Bjerkgård, Terje; Henderson, Iain; Sandstad, Jan Sverre; Schönenberger, Johannes; Slagstad, Trond , 2015

	Geology of the Mauken tectonic window, Målselv, Troms

;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.2015.013;60+kart sider

Abstrakt:

This report presents the results from bedrock mapping in the Mauken tectonic window, carried out in several periods in 2011-2013. During the NGU MINN program, the Mauken area has been subject to a high-resolution airborne geophysical survey (magnetometry, radiometry, EM), followed by bedrock mapping and structural geology investigations. The work in the Mauken area is part of a larger project in southern Troms, with the goal to work out a structural-tectonic-metallogenic model and interpretaion for the basement areas in the whole region.

Berthelsen, Asger , 1967

	Geologic and structural studies around two geophysical anomalies in Troms, Northern Norway.

;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.247;57-77 sider

Abstrakt:

The geology and structures of two windows (the Mauken and the Divielva windows, see fig. 1) are outlined. For the Precambrian supracrustal rocks of the Mauken window, two formations names and one group name are suggested. Hyolithus zone sediments in autochthonous position along the southern margin of the Mauken window show that the Caledonian thrusting exeeded 70 km. In both window structures "ReliefÏberschiebung" took place. A magnetic anomaly in the Mauken window is explained by local concentrations of normally accessoric magnetite in an antiformal hinge zone in sericite-chlorite schists. The relations between an E-W directed magnetic anomaly and the structures of the Divielva window are discussed.

Fareth, E. , 1983

	Målselv. Berggrunnskart; Målselv; 14332; 1:50 000; sort/hvitt;

;Norges geologiske undersøkelse;KART

Fareth, E. , 1982

	Takvatnet. Berggrunnskart; Takvatnet; 15333; 1:50 000; sort/hvitt;

;Norges geologiske undersøkelse;KART

Zwaan, K.B.; Fareth, E.; Grogan, P.W. , 1998

	Tromsø. Berggrunnskart Tromsø M 1:250 000; trykt i farger

;Norges geologiske undersøkelse;KART;1 kart sider

	Abstrakt:
	Beskrivelsen finnes på kartet.

Bjerkgård, Terje; Slagstad, Trond; Henderson, Iain H.C.; Sandstad, Jan Sverre; Schönenberger, Johannes , 2015

	Geology and gold mineralisation in the Mauken Precambrian basement window, Målselv, Troms, northern Norway

;Geological Society of Norway;ARTIKKEL;Norwegian journal of geology; No.95 (3/4);423-443 sider

Referanser som ikke finnes i NGU's Referansearkiv.:

Alnes, A.M., 2013: Geological setting and origin of a gold-mineralized zone at Myrefjellet, Mauken, Troms. Master thesis, University of Tromsø, Norway 96 pp.

Feltprøver

	Prøvenr.	Prøvetype	Diverse
	JSS_1	Fastfjell	Prøvetaker: J.S. Sandstad/...Lager: Løkken Kommentar: Kvarts-arsenkisårer i siltstein, 100 m i ligg fra hovedsone Antall registrerte elementanalyser = 1
	TB-MA_1	Fastfjell	Prøvetaker: T. Bjerkgård/...Lager: Løkken Kommentar: Siltstein med arsenkis og magnetkis Antall registrerte elementanalyser = 1
	TB-MA_50	Fastfjell	Prøvetaker: T. Bjerkgård/...Lager: Løkken Kommentar: Arsenkis i siltstein Antall registrerte elementanalyser = 1
	TB-MA_51	Fastfjell	Prøvetaker: T. Bjerkgård/...Lager: Løkken Kommentar: Arsenkis i siltstein Antall registrerte elementanalyser = 1

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

Navn på lokalitet: Trench 1

(Objekt Id: 32847 18,01,00)

Lokalisering

Fylke:

Kommune:

Mangler ()

Kart 1:50000:

Takvatnet (1533-3)

Kart 1:250000:

Tromsø

Fylke:

UTM-Zone 33 - EUREF89/WGS84

Ressurs

	Ressurstype:	Edelmetaller (Au, Ag, PGE)	Ressursundertype:	Gull
			Element(er):	Au As

Ressurser og produksjon

	Aktivitet:	Prospektering	Reserver:
	Driftsmetode:		Historisk produksjon:

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