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INDUSTRIMINERALDATABASEN
Forekomstområde 1433 - 301
(Sist oppdatert 30.jan.2024)

Navn på forekomstområde : Engebøfjellet
(Objekt Id : 1433,301,00,00)

Lokalisering
Fylke : Sogn og Fjordane (14) Kommune : Naustdal (1433)
Kart 1:50000: Bygstad (1217-4) Kart 1:250000: Florø
Markeringspunkt: Lengdegrad: 5.4351960 Breddegrad: 61.4919090
EU89-UTM Zone 32 (Koordinatene ER bekreftet)
X-koord: 310249 m. Y-koord: 6822770 m.

Materialtype
Hovedtype: Andre industrimineraler Subtype: Granat

Produksjon
Aktivitet: Gruvedrift Reserver:
Prod. metode: Produksjon:
Prod. status: I drift Tippvolum:

Betydning
Offentlig: Internasjonal betydning (reg. 16.02.2015)
Økonomisk: Meget viktig , (Stadfestet 23.jan.2013 av Havard Gautneb)

Mineralisering
Æra: Periode:
Datering: Metode:
Genese: Form:
Hovedtextur: Min. fordeling:
Kornstørrelse:
Strøk/Fall: Retning:
Feltstupning:
Stratigrafisk klassifikasjon av vertsbergart
Æra: Periode:
Provins:
Geotek.enhet:
Tektonisk complex:
Intrusivt komplex:
Gruppe: Formasjon:

Opplysning(er) i fritekstformat
Fri tekst
Dette er den samme forekomsten som Engebøfjellet rutil forekomsten, se informasjon i malmdatabasen.

Litteraturfortegnelser:
Fra NGU's Referansearkiv.:
Korneliussen, A.; Gautneb, H.; Raaness, A. , 2008
Characterisation of garnet, Engebøfjellet rutile deposit
;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.2008.082;203 s. sider
Abstrakt:
This report provides documentation of the Engebøfjellet eclogite and of the characteristics of garnet within it, including quantitative data on the chemical composition of the garnet, the amounts of garnet present and its grain-size distribution. Based on image processing of thin-sections of rutile-ore-type eclogite, the garnet content generally varies from 25 to 40 wt.%, with an estimated average of 33 wt.%. In representative rutile-ore-type eclogite the garnet grain-size is commonly in the range 100 to 250 microns (0.1-0.25 mm) and smaller, but larger garnet grains in the range 300-400 microns seem to occur fairly frequently. Inclusions of other minerals in garnet are common, but the amounts of inclusions in representative "normal size" (less than 250 microns) garnet are generally regarded as low, although precise quantitative data is not available. In general, the amount of inclusions increases with garnet grain-size and may be considerable in the larger garnets. Based on this information it is believed that high-quality garnet concentrates with garnet grain-size in the range 100 to 300 microns, could be produced from representative rutile-ore-type eclogite. The documentation provided and the knowledge behind it represent highly relevant back-ground information for continued mineral processing trials in order to test the possibilities for making garnet concentrates of sufficient quality for various applications.

Korneliussen, A. , 2008
Rutile ore characteristics, Engebøfjellet.
;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.2008.085;74 s. sider
Abstrakt:
During the DuPont/Conoco/NGU Engebøfjellet project (1995-97) 49 boreholes were drilled, altogether 14527 meters. All cores were analysed forTiO2 and Fe2O3 using a portable XRF instrument (Dutokumpu X-Met); approximately 50.000 X-Met analyses were made. A number of core sections, for most of the drill hoies one 10m-section per 100 m core, were also analysed in the laboratory by a combined XRF and ICP-AES "rutile analytical procedure" in which rutil was determined as the difference between TiO2 (total,analysed by XRF) and Ti O2 (acidsoluble, analysed by ICP-AES), giving precise information about total whole-rock TiO2 and other major elements, and semi-quantitative information of the amount of rutile present. The X-Met (XRF) core analyses in combination with surface analyses were the basis for a 3D-model ore resource developed by DuPont. Evaluation of the analytical data from the DuPont-project confirms that the core analyses carried out by the X-Met portableXRF are semi-quantitative. Adjusted X-Met data based on comparison with reference XRF analyses, give a correct overall picture of the TiO2-distribution along the cores as well as providing reliable average numbers for large coresections, but they are not reliable on meter-scale and are only indicative on 10-meter scale.

Korneliussen, A. , 1994
Rutile-bearing eclogites in Western Norway.
;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.94.013;152 sider
Abstrakt:
The eclogite province of W.Norway is subdivided into 8 geographic regions. The three southernmost of these regions - Holsnøy, Dalsfjord and Førdefjord, are surrounded by large areas without known eclogites, while the regions from Nord-fjord and northwards form parts of a large eclogite province. The rutile content is generally 1-2%; 3-4% rutile or more occur within some eclogites in the Holsnøy (Hordaland), Dalsfjord and Førdefjord (both Sogn and Fjordane) regions. Occurrences of high-Ti eclogites are less common, but not absent, in the northern regions. The investigations in 1992 and even more in 1993 were focused on the Dalsfjord and Førdefjord regions which were considered to have the best potential for economic rutile deposit. The investigations in the northern regions in W.Norway (1992) have given significant additional information, but have not revealed rutile mineralizations of economic interest comparable to those known from the Førdefjord and Dalsfjord regions. Because of the need to obtain economically interesting data quickly, continued investigations in the northern regions were postponed, and practically all energy was focused on the Dalsfjord region in 1993, with the main objects at Saurdal and Orkheia in the Fjaler and Hyllestad commune, respectively. This report summarizes available geologic information concerning rutile in eclogites in W.Norway. It also includes information (not confidential when open-file reports are referred to) additional to that obtained with DuPont's participation.

Korneliussen, A.; Braathen, A.; Erambert, M.; Lutro, O.; Ragnhildstveit, J. , 1998
The geology of the Engebøfjell eclogite deposit and its regional setting
;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.98.081;121 sider
Abstrakt:
Fortrolig til 04.05.2003. The Engebøfjellet eclogite deposit is situated at the northern side of Førde- fjord near the small community Vevring in Naustdal kommune, Sogn og Fjordane county, W.Norway. Geologically the Førdefjord area belongs to the "Western Gneiss Region", between the Devonian Kvamshesten basin to the south and the Devonian Håsteinen basin to the North. Recent mapping divide the Førdefjord region into two major geologic units: the Hegreneset complex and the Helle complex. The Hegreneset complex (oldest) contains a variety of amphibolite, eclogite and gabbroic rocks, together with tonalitic to dioritic gneisses. The Helle complex comprises mainly granitic and granodioritic gneisses.

Korneliussen, A.; Furuhaug, L. , 1992
Rutilforekomster i Norge. Resultater og videre planer.
;Norges geologiske undersøkelse;INTERN RAPPORT;Intern rapport; No.92.026;22 sider

Korneliussen, A.; Wanvik, J. E.; Broekmans, M. A. T. M. , 2008
Engebøfjellet: prospect of a major rutile deposit
;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.2007.055;19 s. sider
Abstrakt:
Engebøfjellet is a large rutile deposit within eclogite rock on the northern side of Førdefjord in Naustdal municipality, Sogn og Fjordane county, West Norway. The deposit comprises minimum 300 Mt (million metric tons) of eclogite rock containing 2.5-5 wt% rutile (TiO2, titanium oxide). With an estimated average grade of 3,8 wt% rutile the entire ore deposit contains 11.4 Mt rutile. With a current rutile proce at 675 USD per tonne, the total in-situ value amounts to 8.6 billion USD. With conventional mineral separation processing with 50% recovery, the recoverable rutile represents a value of 4.3 billion USD. Improved mineral processing using novel techniques allows for significantly higher value, perhaps up to 7.0 billion USD. It is likely that adjacent areas north of Førdefjord, particularly eastwards from Engebøfjellet towards Naustdal including the known Steinkrossen deposit, contain additional large amounts of rutile-rich eclogite, similar to Engebøfjellet. Thus, potential additional rutile resources on the north side of Førdefjorden are very significant. In case of rutile extraction with 50% rutile recovery, roughly 98% of the ore comprises mine waste with main silicate constituents garnet, pyroxene, amphibole, etc. The mine waste can safely be deposited, for instance in the adjacent fjord at 300-400 m depth. However, both the bulk availability and the mineral composition of the waste material provide a major opportunity for the development of by-products, increasing value production while at the same time decreaseing the environmental burden.

Korneliussen, A.; Ahrenberg, E.; Furuhaug, L.; Garson, M.; Staw, J.; Fossflaten, G. , 1996
Core-drilling at Engebøfjellet 1995-96; Dhl to Dh5
;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.96.062;155 sider
Abstrakt:
Based on an agreement between Fjord Blokk and Conoco/DuPont a series of drill- holes have been done on the Engebøfjellet rutile-bearing eclogite on the northern side of Førdefjord. The purpose of the project is to investigate and evaluate the rutile resource at Engebøfjellet. The project has been supported by Prospekteringsfondet. This report, which summariezes the results of the first 1000 m of drilling, is preliminary, primarily for Prospekterings- fondet. When the drilling program is finished, at approx. 2200m, all drilling results will be reported together in a comprehensive report. The eclogite is a 2 km long and up to 500 m wide lens-formed eclogite body surrounded by Proterozoic granitoid gneisses. Three major rock types have been distinguished within the deposit. The margins of the eclogite body are dominated by an amphibolitic unit containing amphibolite, amphibolitic eclogite and numerous gneiss bands and interactions. The central parts of the deposit contains a leucogabbroic eclogite unit and a massive Ti-rich eclogite which is the target rock for the rutile investigations. To date (May 1996) 8 drill-holes have been drilled; of these Dh1,2,3,4 and 5 are included in this report.

Korneliussen, Are , 1982
Rutil i eklogittiske bergarter i Sunnfjord.
;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.1717/5;32 sider
Abstrakt:
Sommeren 1980 ble det foretatt detaljprøvetaking av rutilførende eklogitter ved Kvammen, Fureviknipa, Engebøfjellet og Solvik. Økonomisk interessante rutilgehalter på 5-6% er kun påvist i dm - m store partier. Rutilanrikende partier i 100 m-størrelse inneholder i Fureviknipa og Engebøfjellet gjennomsnittsgehalter på inntil 3-3,5% rutil, mens Kvammen og Solvik er noe fattigere. Det er utført orienterende oppredningsforsøk på prøvemateriale fra Engebø- fjellet uten at det har lyktes å framstille et rutilkonsentrat. Sunnfjords eklogitter representerer betydelige rutilreserver men er i dagens situasjon for lavgehaltige til at videre prospekterings- og opprednings- undersøkelser bør utføres.

Korneliussen, Are ; McLimans, Roger ; Braathen, Alvar ; Erambert, Muriel ; Lutro, Ole ; Ragnhildstveit, Jomar , 2000
Rutile in eclogites as a mineral resource in the Sunnfjord Region, Western Norway.
;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU Bulletin; No.436;39-47 sider
Abstrakt:
The world's resources of the primary titanium raw materials ilmenite and rutile are very large. However, there is a lack of high-grade, high-quality ilmenite deposits as well as good rutile deposits. Particular focus has been given to rutilebearing eclogites in the Sunnfjord region of western Norway, due to a combination of factors such as high rutile content over significant volumes of rock and favourable rutile grainsize. Eclogites in the Sunnfjord region are found in a number of elongated lenses up to 3-4 km long, surrounded by gneisses of amphibolitic to granite composition, as well as numerous smaller eclogite bodies and eclogitised mafic layers in gneisses. The eclogites originated by high-pressure and temperature alteration of Proterozoic, Fe-Ti rich, gabbroic rocks, and were strongly deformed under eclogite-facies netamorphism and thereafter variably affected by retrograde processes. Eclogites in which conversation of ilmenite to rutle was complete and in which this mineral assemblage was negligibly affected by subsequent retrograde processes, are those of greatest economic potential. An example of such an eclogite is the Engebøfjellet eclogite on the north side of Førdefjord, Naustdal commune.


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