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Lappland East of the MountainsBy JIM LUNDQVIST, GUNNAR WISTRAN D and SVEN RUNETHE LANDSCAPE oF LAPPLAND EAsT oF THE ScANDEsBy Jim LundqvistThe Pre-Cambrian peneplane, which forms theextensive and uniform area of Lappland east ofthe mountains, is part of the vast Baltic Shield(cf. p. 2). Being far older than the Caledonianmountain chain or the Scandes in the west it hasbeen submitted to epochs of denudation, foldingand again breaking down long before the Scandeswere formed. East of the "glint" (the eastern edgeof the overthrust nappes) we find to-day a wideplateau land forming the greater part of Lappland,separated from the coastal lowland to the east bythe highest coastal line. The elevation is about200-600 m above sea level and the area can bedesignated as a region of till-covered forested ridgesand plains rich in swampy woodland and mires.This type of upland country covers t of the totalarea of Sweden, and nearly half of it is in Lappland.In southern Lappland the uplands have a markedrelief but further north the flat country is brokenoly by scattered hills and a few low mountainsbeside the rivers and the lakes. Many of the elongatedlakes or lake chains of the eastern Scandesextend into this region.The geological conditions of this country (seeGAVELIN & KULLING 1955 and 0DMAN 1957) arenow known in detail thanks to research and prospectingfor the promotion of the mining industrywhich flourishes since the beginning of this century.The most extensive part of eastern Lappland isformed by large areas of different granites, inthe north the Lina-Arjeplog-Palja and the Kiruna­Arvidsjaur granites and in the south the Revsundgranite; for the most part this type of bedrocknourishes a very monotonous and poor forest flora.But accompanying the Kiruna-Arvidsjaur granitesand porphyries there also appear more favourablerocks, especially volcanic and sedimentary rocks,e.g. phyllites of different age and structure. Amongthem the Snavva-Sjofall series in the north-westoccasionally contains layers of limestone, causinga richer and more varied flora. Small areas ofmigmatites and veined gneisses (the Vakko-Vargforsformation), gabbros, etc., are scattered overthe whole territory. Basic lavas and sedimentsoccur mainly around the great mining fields atKiruna and Svappavara in the north (a small limestonearea at Masugnsbyn near the Lapponianborder in the north-east) and around Mala andAdak in the south.A botanically favoured area is situated in southernLappland close to the edge of the mountain range,where a narrow fringe of the autochthonous, largelycalcareous Cambro-Silurian of Jamtland occurs.Further northwards this zone becomes very narrowand gradually looses its upper (Ordovician) component,leaving only the non-calcareous Cambrian.The rock surface appears only rarely, beingnormally buried under a deep (5-25 m) cover ofmorainic origin, a till consisting of particles ofvariable size, the coarse fractions . (from hugeboulders to fine sand) usually predominant. It wasto the greater part formed from the underlyingrock through the grinding effect of the ice. Atthe end of the glaciation the coast line was hereabout 200-250 m higher than at present. This oldcoast line formed bays that cut across the Lapponianborder deep into the present river-valleys and gaverise to a zigzag borderline between the inlandplateau and the lower river valleys and coastallowland. Just below the highest coastal line alongActa Phytogeog.r. Suec. 50