Estonia is situated on the level Northwestern part of the East- European platform, on the area next to the Fennoscandian shield. Since the end of the Proterozoic period, the Fennoscandian shield, situated north of Estonia, has been mostly mainland, constantly abraded by outer forces. Therefore the crystalline stones in Finland are exposed right on the ground, but in Estonia these stones are covered with sedimentary rocks.

The igneous and metamorphic rocks from the Proterozoic form the basement of Estonian territory. These are mostly gneiss, quartzite and slates, also Finnish red granites. There are no bedrock denudations in Estonia. In North Estonia the bedrock lies in the depth of 100 meters, in South Estonia it lies even deeper in the ground.

The sedimentary cover is formed by different sedimentary rocks, which originate from the Cambrian, Ordovician, Silurian and Devon geological periods of the Paleozoic era some 650-350 million years ago. The lakes and rivers covering the territory of Estonia at these times left here a lot of sediments, which in the process of millions of years transformed into sedimentary rocks, mostly lime stones and sandstones. The depth of these stones varies from 100 meters in North Estonia to 600 meters in South Estonia. The base rock is exposed on several riverbanks and the North-Estonian Glint.

The quaternary deposits covering the limestone and sandstone layers are initially thin everywhere in Estonia: less than 5 meters in North, West and Central Estonia, on the limestone layer they are even missing at all. However, on the South-Estonian highlands the residual soil is thicker than 100 meters. The residual soil is formed mostly by moraine, sands, gravel, peat etc. Everywhere in Estonia the big boulders can be found, brought here from Scandinavia by the continental glacier.

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