Deposit Geology The Kiruna iron oxide-apatite mineralisations are located within the volcanic and volcano sedimentary formations of the Kiirunavaara group. Iron mineralisation is found in two stratigraphic positions, with the Kiirunavaara and Luossavaara iron ore bodies and the satellite Konsuln ore body located at the contact of the Hopukka and Luossavaara formations and the Per Geijer mineralisation (Rektorn, Haukivaara, Henry and Nukutus) being located higher in the stratigraphy, at the contact of the Luossavaara and Matojärvi formations and also within the latter. The trachyandesitic Hopukka formation forms the footwall of the Kiirunavaara and Luossavaara iron ore deposits. It is composed of intermediate lavas that commonly show plagioclase phenocrysts in a fine-grained grey groundmass. Magnetite and apatite veins or schlieren are relatively common in the trachyandesite. Porphyritic rhyodacite of the Luossavaara formation forms the hanging wall of the Kiirunavaara and Luossavaara ore deposits. The unit consists of red, grey, or brown pyroclastic tuffs, ignimbrites, and lavas that in places show flow banding texture. In the middle part of the formation, between the Luossavaara and Rektorn ore bodies, there is at least one zone of agglomerate, which exhibits magnetite nodules (e.g., Geijer 1968). The magnetite orebodies are crosscut by felsic dykes that are compositionally similar to the rhyodacite. These dike porphyries are present both in the footwall and in the ore, ........

Kiruna mine is technologically advanced and uses the latest equipment and techniques to extract iron ore on a large scale from around 1000 metres below ground level. Iron ore is extracted by the Sub-Level Caving (SLC) mining method at an average annual production of 27.5 Mt/y, which makes the Kiruna Mine one of the largest underground mines in the world and the largest SLC operation in the world.

A transverse SLC layout is mainly used. Ore is transported in the mine by LHDs which load ore from drawpoints, haul to and dump into orepasses. Groups of up to four orepasses (‘Tap grupp’ or ‘TG’) feed loading galleries from where material is transported using an automatic train haulage system located on the 1365 main level to a central crushing and skip hoisting system. Five internal shafts hoist the material from 1465 level to 775 level where hoisted material is redistributed to eight shafts for hoisting from 898 level to surface. Hoisted material is then delivered to the Sorting Plant for beneficiation.

The sub-level cave operation is based on the establishment of a main level at 1365 level which was commissioned in 2008. Full production was achieved from the 1365 Level in 2016 following a transition of production from the 1045 Main Level.

In 2022, Kiruna mine completed 10.0 km of development, down from 14.8 km excavated in 2021. This includes development required for capital investment, mine operations and development of a tunnel for exploration o ........

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