Metallogeny and tectonic evolution of the Northern Fennoscandian Shield: Field trip guidebook / Металлогения и тектоническая эволюция Северо-Фенноскандинавского щита: Путеводитель полевой экскурскии

The Fennoscandian Shield forms the north-westernmost part of the East European craton and constitutes large parts of Finland, NW Russia, Norway, and Sweden (Fig. 1). The oldest rocks yet found in the shield have been dated at 3.5 Ga (Huhma et al. 2004) and major orogenies took place in the Archaean and Palaeoproterozoic. Younger Meso- and Neoproterozoic crustal growth took place mainly in the western part, but apart from the anorthositic Ti-deposits in SW Norway, no major ore deposits are related to rocks of this age. The western part of the shield was reworked during the Caledonian Orogeny.

Economic mineral deposits are largely restricted to the Palaeoproterozoic parts of the shield. Although Ni–PGE, Mo, BIF, and orogenic gold deposits, and some very minor VMS deposits occur in the Archaean, virtually all economic examples of these deposit types are related to Palaeoproterozoic magmatism, deformation and fluid flow. Besides these major deposit types, the Palaeoproterozoic part of the shield is also known for its Fe-oxide deposits, including the famous Kiruna-type Fe-apatite deposits. Large-tonnage low-grade Cu–Au deposits (e.g., Aitik), are associated with intrusive rocks in the northern part of the Fennoscandian Shield.

These deposits have been described as porphyry style deposits or as hybrid deposits with featuresthat also warrant classification as iron oxide–copper–gold (IOCG) deposits (Weihed 2001, Wanhainen et al. 2005). <...>