Fossils Mickwitzia monilifera and olenellid trilobite fragments are found in the greenish grey shale in the lower sediment formation of Söderfjärden at a depth of 237.8 and 278.05 m. Microfossils (acritarchs) Archaeodiscina umbonulata, Baltisphaeridium cerinium, Granomarginata squamacea, Lophosphaeridium tentativum, Tasmanites bobrowskii, T. piritaensis were also observed in the lower part of the Söderfjärden sedimentary formation. In this lower intersection the microfossil genera resemble those in the upper sediment formation. Only one new species, Dictyotidium bottnicum, is described in the lower portion of the formation. The occurrence of the fossils and microfossils in the Söderfjärden sediment formation suggest Lower Cambrian sedimentation.

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Lake Sysmljirvi is located inside the municipal boundary of Outokumpu in North Karelia, Finland. Since 1928 metalliferous, and at a later stage highly acid waste-water, has been discharged into the lake. Neutralization of the lake water by liming was introduced, and by the end of 1966 the pH of the water had become neutral to alkaline.Two sediment cores (0.5 m and 5 m long, respectively) were analyzed for pollen, diatoms, loss-on-ignition, organic carbon, Fe, Cu, Ni, Pb, Zn and Hg. The maximum concentrations of organic matter and heavy metal content occur 30 cm below the sediment surface. Evidence of the liming and of accelerated eutrophication appear close to the surface of the sediment (0-10 cm), indicated by an increase in Nitzschia plana.

The Pieksämäki-Juva region is strongly drumlinized. According to seismic refraction data, the average thickness of the till forming a drumlin in Pieksä-mäki is about 20 meters. The drumlins in Joroinen are mostly low and narrow. According to seismic data, the till is also much thinner, averaging only 7 meters. The drumlins in the study area were formed, according to the authors, at a very late stage of the glaciation in the wide marginal region of a thinning glacier terminating in fairly shallow water. The weak glaciofluvial activity of the glacier could also have been a factor contributing to that formation, although in the final stage, it has been a question of the reactivation of the ice-flow.The most important of the presented sediment profiles from bogs is the stratigraphic section from the Vuorilampi-pond in Jyväskylä. It is located west of the proximal part of the marginal formation. The C 14 -age of the oldest dateable sediments from this area was 8 130 ± 160 B.C. According to pollen statistics, it corresponds to the beginning of the Preboreal or the end of the Younger Dryas period. Due to the possibility of having interglacial organic matter in the sample, the validity of the dating should be accepted with some reservation. It is, however, supported by the C 14 -dating made by Salmi (1962) from the oldest organic sediments of the Lapaneva bog in Kihniö, west of Jyväskylä.

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