Risto A. Kumpulainen, 2011. "The Neoproterozoic glaciogenic Lillfjället Formation, southern Swedish Caledonides", The Geological Record of Neoproterozoic Glaciations, Emmanuelle Arnaud, Galen P. Halverson, Graham Shields-Zhou
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The Tossåsfjället Group, which crops out in the Middle Allochthon of the Scandinavian Caledonides, contains the glaciogenic Lillfjället Fm. Evidence that supports the interpretation of the Lillfjället formations as glacially related include the presence of diamictite beds, the presence of lonestones, although few, in laminated units, one possible faceted clast, involution-like deformation structures, and the presence of sandstone wedges cutting 2.5–3 m down into two different diamictite beds. Similar to the other glaciogenic formations in southern and central Scandinavia (Moelv and Långmarkberg formations), the Lillfjället Fm. rests on a unit of peritidal, sabkha-type dolomite of the Storån Fm. Poor exposure contributes to the uncertainty about the thickness of the formation. In this account, the Lillfjället Fm. stratigraphy has been divided into three subunits: (i) a lower diamictite-dominated unit, (ii) a middle unit composed of distinctly laminated grey sandy mudstone and (iii) an upper diamictite-dominated unit. There is no information available from the Tossåsfjället Group concerning palaeolatitudes and chemostratigraphy. Poor isotopic evidence (40Ar/39Ar) from the Ottfjället Dolerites, which cut the Tossåsfjället Group, indicates that the succession is older than c. 665 Ma, so a reliable correlation with global glaciation events is not yet possible.