What is the Alpine orogeny in this context?

The Alpine orogeny is the Tertiary mountain-building process that lifted, folded and faulted many of the peninsula's units. The document links it to the formation of most cordilleras and to the uplift of older massifs.

Which units are made of Paleozoic materials?

The Galician Massif, the Asturian Massif, the central and eastern Pyrenees' axial zone, the Central System, the Montes de Toledo, the Sierra Morena and the Penibetic Cordillera are described as made of Paleozoic materials.

What kind of relief does the Ebro Depression have?

The Ebro Depression is a pre-Alpine basin filled during the Tertiary with eroded sediments, and its relief is mostly flat.

Morphostructural Units of the Iberian Peninsula: Massifs, Cordilleras and Basins

Summary

This document describes the main morphostructural units of the Iberian Peninsula, including massifs, cordilleras, depressions and plateau sectors. For each unit it explains the geological materials, the role of the Alpine orogeny and the resulting relief. Students will learn how Paleozoic massifs, Tertiary uplifts and sedimentary basins shaped the peninsula's landscape.

Key points

The Alpine orogeny (Tertiary) uplifted and folded many units, such as the Cantabrian Cordillera, the Pyrenees and the Betic Cordillera.
Paleozoic massifs, such as the Galician, Asturian and Central System, form the oldest rocks and typically have rounded or high, abrupt reliefs.
The Ebro and Guadalquivir depressions are basins filled with sediments eroded from surrounding mountain ranges.
The Submeseta Sur is divided into the Tajo and Guadiana hydrographic basins by sedimentary materials.
The Betic Cordillera is made mainly of marl, limestone and clay, forming folded ridges.
The Sierra Morena is a fault-bounded escarpment that forms a stair-like step between the valley and the plateau.

Test yourself

Morphostructural Units of the Iberian Peninsula

Galician Massif

The Galician Massif underwent Tertiary rejuvenation during the Alpine orogeny. It forms the western part of the northern Meseta plateau and is made up of Paleozoic materials. Its relief consists of rounded mountains cut by numerous fault systems.

Cantabrian Cordillera

The Cantabrian Cordillera was formed during the Tertiary as a consequence of the Alpine orogeny. In the western sector of the cordillera, the Asturian Massif is made up of Paleozoic materials and forms a relief of high peaks and abrupt slopes. In the eastern sector, the materials are Secondary and Tertiary sediments deposited in a sea that covered the northern edge of the plateau. The Alpine orogeny lifted these materials and produced diverse karst modeling.

Basque Mountains

The Basque Mountains are the prolongation of the Prepyrenees and were uplifted during the Alpine orogeny. Their relief consists of high, rugged peaks formed by folded and faulted materials, with soft slopes and valleys.

Pyrenees

The central and eastern Pyrenees are formed by a Paleozoic axial zone, the oldest part of the ancient Hercynian massif, rejuvenated during the Alpine orogeny. This zone has high altitudes and abrupt relief. In the Prepyrenees, secondary and tertiary materials were folded and elevated during the Alpine orogeny, forming high ridges and soft hills.

Submeseta Norte

The Submeseta Norte was shaped by Tertiary Alpine orogeny, which caused the subsidence of some blocks along the Mesta river. It is composed of interior sedimentary materials of varying hardness, creating a relief of plains, meadows and low hills.

Iberian System

The Iberian System is composed of secondary materials deposited in a sea that covered the eastern edge of the plateau. These were folded during the Alpine orogeny. Its Tertiary materials overlie Paleozoic materials, and its relief includes siliceous and granitic rocks.

Ebro Depression

The Ebro Depression is a pre-Alpine basin that was filled during the Tertiary by sediments eroded from the new mountain ranges that surround it and from the old massifs. Its relief is mostly flat.

Catalan Coastal Range

The Catalan Coastal Range is formed by Paleozoic materials and the remains of the old Catalan-Balearic solid mass, which was not lifted by the Alpine orogeny. It is split into two alignments, between which a longitudinal depression filled with Tertiary and Quaternary materials extends. Its relief consists of soft hills and valleys.

Central System

The Central System emerged during the Tertiary through the uplift and fracturing of the old massif. It is made of Paleozoic rocks, with flat summit surfaces exceeding 1000 m in height.

Montes de Toledo

The Montes de Toledo emerged during the Tertiary with the same character as the Central System. They are low mountains and hills with relatively low relief, not reaching 2000 m. They are composed of Paleozoic rocks, quartzites and slates.

Submeseta Sur

The Submeseta Sur was also shaped by the Alpine orogeny. Subsidence of some blocks along faults produced sedimentary interior materials, which divide the area into two hydrographic basins: the Tajo and the Guadiana. Its rock is clay.

Sierra Morena

The Sierra Morena was formed by the Alpine orogeny. It is a great fault-bounded escarpment produced by the push of the Meseta to the south, which raised the Betic materials. Its relief is composed of Paleozoic rocks and forms a stair-like step between the valley and the plateau.

Guadalquivir Depression

The Guadalquivir Depression is a Tertiary depression resulting from the Alpine orogeny. It is located between the Subbetic Cordillera and the solid spherical massif. It was initially open to the sea and later became a lake. Its relief consists of undulating clay countryside and Tertiary rocks.

Betic Cordillera

The Betic Cordillera was formed in the Tertiary by Alpine orogeny, through the folding of sediments deposited in the Pyrenean trough. Its rocks are mainly marl, limestone and clay. The relief shows limestone layers that form folded ridges with hard materials.

Penibetic Cordillera

The Penibetic Cordillera is formed by Paleozoic materials belonging to the ancient Hercynian massif of the Betic-Rif, which were uplifted during the Tertiary by the Alpine orogeny. Its relief is steep, with the highest altitudes bordering the Mediterranean coast.