A notable feature of Finland are the asar or narrow ridges of morainic deposits, more or less reassorted on their surfaces.
Till drumlins, notably abundant on the lowland about Boston and the highland near Spencer; morainic hills, extending, e.g.
Within the Archean protaxis they are of the most varied shapes, since they represent merely portions of the irregular surface inundated by some morainic dam at the lowest point.
The formation of morainic dams, and in some cases the perhaps from the incidence of erratic upheaval of the land.
The Quaternary epoch is represented by vast morainic deposits in the valleys of the Tian-shan.
Eastward from the main mountain range the highland region is divided into two belts: a middle belt of morainic deposits and marshes, and a coastal belt.
The coast of the Baltic is rocky only in the island-studded region at the head of the Baltic basin proper - a submerged lake-districtand the littoral generally is a typical morainic land, the work of the last great Baltic glacier.
Its sources are in the morainic lakes in northern Minnesota; Lake Itasca being only one of many glacial lakes which supply the headwater branches of the great river.
This depression is occupied in great part by a series of lakes, some of these filling transversal breaches in the range, whilst others are remains of glacial reservoirs, bordered by morainic dams, extending as far as the eastern tableland and corresponding in these cases with transversal depressions which reach the Atlantic Ocean.
Thus local sheets or aprons of gravel and sand are spread more or less abundantly along the outer side of the morainic belts; and long trains of gravel and sands clog the valleys that lead southward from the glaciated to the non-glaciated area.