The Garpenberg mine is situated in the mineralized Palaeoproterozoic igneous province of Bergslagen, south central Sweden, which is host to a variety of ore deposits, and especially Fe-oxide and polymetallic sulphide deposits. Garpenberg, which is the largest sulphide deposit in the region, consists of several individual ore bodies distributed over a distance of 4 km within the Garpenberg supracrustal inlier, see Figure 3-3. The main host rock to the ore is calcitic marble (limestone) altered to dolomite and Mg +/- Mn-rich skarns. The footwall consists of rhyolitic pumiceous, graded massflow breccia and rhyolitic ash-siltstone and sandstone affected by strong phlogopite-biotitecordierite-sericite-quartz alteration. The hanging wall includes polymict conglomerates and rhyolitic pumiceous breccias. The stratigraphic succession is attributed to the volcanic cycle of a felsic caldera complex. The pumiceous breccias in the hanging-wall record a climactic eruption that formed a caldera over 500 m deep and over 9 km in diameter in the Garpenberg area. The limestone horizon is interpreted as a stromatolitic carbonate platform, formed in a shallow, marine environment during a hiatus in volcanism.

The Garpenberg inlier has been interpreted as a NE-SW trending, tight to isoclinal complex syncline with a sub-vertical axial plane (Allen et al., 2003). The structure is compressed at the southern end and opens to the north. The ore-host limestone shows a complex geometry due to l ........

Garpenberg is a Zn-Pb-Ag-(Cu-Au) underground mine where the ore is mined from between 450 meters to more than 1 400 meters below surface. The mine encompasses several polymetallic ore bodies. Almost 80 % of the mined tonnage derives from the largest ore body, Lappberget. Almost 90% of the mined ore in Garpenberg is extracted by sublevel stoping (also called longhole stoping), where the ore is mined in layers between two drifts vertically 25 m apart. Most areas are mined with transversal longhole stoping, where the development and stope axis are perpendicular to the strike of the orebody. In some more narrow areas, longitudinal longhole stoping is used. The orientation of this method is along or parallel to the strike of the orebody. The ore body is split into primary and secondary stopes, which are mined in a predefined order and pyramid shape sequence. The standard stope dimensions are 24 - 25m high, 10 m wide for primary stopes and 15 m wide for secondary stopes. In general, the ore bodies are divided in mining blocks with 6 levels of stopes in each block. The last level of each mining block is the sill pillar, which separates the different mining blocks. This division allows the mine to have several production areas being scheduled and mined at the same time. Another consideration that was recently introduced concerning the mine design of Lappberget is the division into a main and a second pass sequence (2pass). The main sequence contains more of the high-grade areas an ........

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