Skandinaviens Geokronologi

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Abstract
This paper gives a brief account of the present material of varve measurements from all over Sweden and vicinity, The first radial lines accomplished, datings were mainly made in marginal directions, although radial lines are at work. Here is also discussed saltwater softened by outstreaming meltwater, forming different types of symmigt varves, and further on the main moraine extension as in Finland possibly due to a revived ice-center in the N Bothnic region. Two easterly saltwater influxes arrived just after each enduring morainic stop, Ss I and II, and two westerly, one preliminary in - 1073 B. Z. (B. Z. = Before Zero) and the greater one from -978 on, this latter only through the Närke strait, according to several precise varve determinations. The drainage of the Baltic ice lake at Mt Billingen is found to be complicated, as the lake for a long time was locked by a broad ice lobe close E of Mt Billingen from -1260, Daltorp, to -1140 B. Z. This is just after the final stage of the Ss II with the entrance of the second marine stage in Finland. The Daltorp lobe mentioned may have left a narrow channel along the steep mountain side, where the seam between ice and rock wall may have permitted a slow leaking out of the lake water for a long time, gradually lowering the lake in concordance with Nilsson's find of a too great divergence between the Baltic and Yoldia shorelines to allow one sudden drainage only. Also Caldenius' measures of varves in the Tidan ice lake show repeated disturbances, which now may be referred to special dated drainings, beginning in -1140 at Billingen, culminating -1077 at Mölltorp, until at last, in -1073, the first saltwater influx could enter through Lake Viken, while the second and far more enduring one entered through the early openings of the Närke strait 95 years later, in -978 B. Z., reviving the symmiet type of clays in Finland, H 2. Another lake drainage just dated is that of G. Holmsen's ice dammed lakes in the upper Glommen valley (1915). The eatastrophe took place in -522. It deposited at the boundary a vast gravel delta and brought a mega varve of fine silt unto the outlet of River Byälven at the W shore of Lake Vänern at Säffle, VI (p. 307, 323). Finally is mentioned De Geer's original dating in 1909 within Ragunda of the Zero year at the varve locality Vikbäcken by a mega varve just below the biotic, dark and micro-varved clay, which he then determined to denote the arrival of the Postglacial Period (1910, pp. 3, 4, 1912, p. 251, Pl. 1). That type of clay must have simultaneously begun to be formed at Storedan, after the last mega varve was formed and the ice-lake draining had ceased, all in concordance with a correction of 84 years in the dating of this latter locality. The Cochrane-Bell moraines in Canada seem, to judge from Antevs' extensive varve counts, to have been of still younger date. Greenland's ice cover may be a last continuous relict from the big glaciation in a glacial concentration towards the Atlantic, where Greenland has a central situation. De Geer's system and C 14, by repeated concordance, both prove to be exact and thus supporting each other (GFF 1953, 403, 417).

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