Ala Lombolo
- One of Sweden's most polluted lakes

The Kiruna area is seated within the Svecokarelian orogeny which took place between 2.00 to 1.65 Ga, making it the oldest orogen in Sweden. As well as the rest of Sweden, the area has been affected by several glaciations during the Quaternary period. The latest ice sheet left the northern parts of Sweden about 10 000 years ago and the glacial deposits seen today are mainly remnants from that glaciation. (SGU, 2017)

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The sediment deposits around Ala Lombolo consist of till with a thickness of 2-3 metres. The grain size composition of the till varies around the lake, with a coarser, sandy and gravelly till found northeast of the lake and a finer, more silty till dominates to the north, south and west. Large parts of the till surrounding the lake is covered with peat of varying thicknesses and there are also areas west and north of the lake which are overlain by silt. (Kiruna kommun, 2016)

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The bedrock in the lake area is constituted of a quartzitic sandstone which exhibit fractures in an east-northwestern direction (Kiruna kommun, 2016). According to the bedrock map of the area created by Bergman, Stephens, Andersson, Kathol & Bergman (2012), it belongs to the lithological unit consisting of metamorphic sedimentary or volcanic rocks. Since the area is within the Svecokarelian orogeny it is likely that the sandstone show metamorphic structures. The rock types found in the vicinity of the lake is represented by a variety of volcanic, plutonic, sedimentary and metamorphic rocks (Bergman et al., 2012) and to the west of the lake a porphyry is found (Kiruna kommun, 2016).

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