Tienpohja

Tienpohja is a geographical term referring to the lower layers of bedrock or glacial till that underlie the soil and are visibly exposed in road cuts or along rivers. It is a Finnish term that literally translates to "road bottom".

In a broader sense, the term tienpohja can also be applied to other areas where the underlying bedrock is visible, such as in areas of scenic geological interest or in road construction projects. The exposure of tienpohja provides valuable information about the geological history of an area, including information about past glacial movements, tectonic activity, and erosion patterns.

Tienpohja can be composed of a variety of rock types, including granite, gneiss, and basalt, among others. It is often visible in areas that have been subject to glacial erosion, where chunks of rock have been uplifted and exposed. In these areas, the tienpohja can provide glimpses into the pre-glacial or meta-sedimentary geological past of the region.

In road construction, tienpohja can be of significant interest due to its role in indicating the underlying bedrock structure. This information can be crucial for engineers, as it helps them estimate the stability of the terrain and make informed decisions about road construction and maintenance. By studying tienpohja, geologists can also gain insights into the region's geological history, which can be enlightening for both local communities and those interested in the natural environment.