Norsk versjon
THE ORE DATABASE
Deposit Area 1201 - 015
(Last updated 25.jan.2024)

Name of Deposit Area : Trengereid
(Object Id : 1201,015,00,00)

Location
County : Hordaland (12) Municipality : Bergen (1201)
Map 1:50000: Bruvik (1215-4) Map 1:250000: Bergen
Marking point: Longitude: 5.6071290 Latitude: 60.4208370
EU89-UTM Zone 32
X-coord: 313218 m. Y-coord: 6703092 m.

Commodity
Main Type: Ferroalloys (Cr,Ni,Co,V,Mo,W) Sub Type: Nickel
Element(s): Ni Cu

Importance
Public: Little Importance (reg. 18.02.2015)
Economical: Minor interest , (Confirmed 15.feb.2005 by Lars Petter Nilsson)

Mineralization
Era: Paleozoic Period: Ordovician
Dating: Method:
Genesis: Form:
Main texture: Min. distribution:
Main grain size: Main alteration:
Strike/Dip: Direction:
Plunge:
Stratigraphic classification of host rock
Era: Paleozoic Period: Ordovician
Province: Caledonides
Geotec.unit: Hardangerfjord Nappe Complex
Tectonic complex:
Igneous complex: Gulfjell Ophiolite Complex
Group: Formation:

Information(s) in free text format
Free text
Den eventuelle Ni-mineraliseringen plotter i dag sentralt i et større kalksteinsbrudd (Risnes) og må være feil-lokalisert.

Bibliography:
From NGU's Reference Archive:
Ragnhildstveit, J.; Naterstad, J. , 1993
Samnanger. Berggrunnskart; Samnanger; 12154; 1:50 000; sort/hvitt;
;Norges geologiske undersøkelse;KART

Heskestad, Britt; Hofshagen, Nina H.; Furnes, Harald; Pedersen, Rolf-Birger , 1994
The geochemical evolution of the Gulfjellet Ophiolite Complex, west Norwegian Caledonides
;Norsk geologisk forening;TIDSSKRIFTARTIKKEL;Norsk geologisk tidsskrift; No.74 (2);77-88 pages
Abstract:
The earliest (N-S to NE-SW striking) dykes and pillow lavas of the Lower Ordovician Gulfjellet Ophiolite Complex are dominated by N-MORB to IAT-types affinities, the IAT-type seems to become more abundant with time. This development is thought to reflect spreading-related magmatism is a 'supra-subduction' zone environment. Boninitic magmatism, represented by dominantly NE-SW to E-W trending dykes, post-dates the N-MORB and IAT, and suggests formation in a fore-arc setting. The occurr- ence of a few MORB-type dykes cutting boninite dykes may indicate formation of new oceanic crust, possibly associated with arc splitting. The rare occur- rence of post-MORB calc-alkalice magmatic activity may indicate a maturing stage of arc magmatic activity.


The fact sheet was created on 19.05.2024

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