European Relief: Geological Formation and Morphostructural Units

European Relief: Major Morphostructural Units

As a result of geological evolution, Europe possesses several distinct morphostructural units:

1. The Baltic or Fennoscandian Shield

This unit occupies most of Finland and Sweden and the far northwest of Scotland. It is a flat, badly eroded area, which corresponds to a Precambrian erosion surface that has remained stable so far.

2. Platforms, Ancient Massifs, and Sedimentary Basins

These features are primarily related to the devastation caused by erosion following the Primary Orogenies (Caledonian and Hercynian).

Platforms (Sockets)

The **platforms** are flat areas that arise from the erosion of the ridges raised during the two Primary Orogenies: the Caledonian and the Hercynian. These platforms were fractured by subsequent orogenic pressures, which lifted some blocks, leading to the **ancient massifs**, and sank others, forming **sedimentary basins**.

Ancient Massifs

The **ancient massifs** present mild forms of no great height. Examples include:

• The Scandinavian Mountains.
• The Scottish Beds (such as the Highlands of the North, South Highlands, and Mount Grampian).
• The massifs of Southwest Ireland and Wales (such as Mount Cambrian).
• Hercynian massifs located in Great Britain (Cornwall and the Pennines).
• Continental Hercynian massifs: the Bulge in Belgium, the Black Forest and the Rhenish Massif in Germany, the forests of Thuringia and Bohemia, and in France, the Vosges and the Massif Central Français.

Sedimentary Basins

Sedimentary basins are now low-lying reliefs. The Caledonian basins were covered by the sea, as in the North Sea, or filled with sediment, as in the Scottish Lowlands. Other major sedimentary basins are located in London, Paris, Germany, and Spain.

3. Alpine Ranges and Depressions

These features were formed following the Tertiary Alpine Orogeny.

Alpine Ranges

The **Alpine ranges** are located in Southern Europe and were raised by the folding of sediments deposited in the Tethys Sea when the African plate collided with Europe. This collision caused the formation of the Pyrenees, the Alps, the Apennines, the Balkans, the Carpathians, the Pindus, and the Caucasus.

Post-Alpine Depressions

Post-Alpine depressions arise on both sides of the ranges. They are filled with limestone and clays and are traversed by major rivers, including the Po (Apennine Depression), the Guadalquivir Depression, and the Aquitaine Depression (France).

4. The Great Plains of Northern Europe

The Plains of Northern Europe owe their present form to Quaternary climate oscillations. The **coastal plains** resulted from marine transgressions and regressions, while the **interior plains** were shaped by the advance and retreat of the glacial ice cap.

5. Volcanic Islands

The **volcanic islands** (Canary, Azores, and Madeira) were formed in the Tertiary period from volcanic emissions.