The Second Salpausselkä at Karkkila, southern Finland

This paper describes the results o f glacial geological field investigations carried out in 1974 in the 10 km wide zone of the Second Salpausselkä in the area between Karkki la and Loppi in southern Finland. The 2nd Salpausselkä runs in three main parallel belts, each of them fo rming one or several broken rows of moraine ridges, g laciof luvia l deltas of var ious types, and other transverse formations and deposits. The »transverse eskers» described in some previous papers are interpreted by the present author in the main as gradual fo rms of glaciofluvial marginal deltas, deposited in general in the sea in f ront o f the ice margin. The typical and flat-topped f o r m s o f delta in general grew up to the water level o f the ancient Baltic Ice Lake, situated in the study area at 1 4 0 — 150 m above sea level. The sharp-crested primary f o r m o f delta did not g row up to water level. The meltwater streams also produced, in addition to separate deltas, radial eskers, of ten rich in deltas, too. The activity of the ice is shown by the halts or short advances. The 2nd Salpausselkä system was formed in three main stages and the format ion lasted about 200 years, 8 5 0 0 — 8 300 B.C.