Spanish Plateau: External Ridges, Troughs, and Coastal Relief
External Ridges and Troughs of the Spanish Plateau
The Pyrenees occupy the isthmus peninsula from the Bay of Biscay to Cape Creus. It stretches over 435 km and forms a compact and rugged mountain barrier. The Pyrenees are an Alpine range model for its structure and its geological landforms. Inside, two zones are distinguished: the axial Pyrenees and the pre-Pyrenees.
Ebro Basin
The Ebro Basin comprises the lowlands located in northeastern Spain. Its origin and geomorphological evolution are associated with the mountain systems of its outline. Transported material is deposited selectively according to their thickness, positioning itself as the finest course in the central depression and thicker near the coastline. The depression, however, retains remnants of the old tabular reliefs, known by the expressive names of tables or wheels.
Cordillera Costero-Catalana
This ridge closes the Ebro basin to the southeast, is interposed between this and the Mediterranean Sea, sealed and insulated from the marine influence. Oriented northeast to southwest along more than 250 km, it offers a remarkable complexity arising from its transverse and longitudinal fragmentation. This line can be divided into 2 units. The longitudinal ridge breaks down into 3 units that run parallel to each other and with respect to the Mediterranean Sea: the coastal range, the littoral depression, and the littoral cordillera.
Betic Cordilleras
The Betic Cordilleras occupy southern Spain from the Strait of Gibraltar to Cape La Nao. They emerged in the second half of the Tertiary Era as a result of the Alpine folding and the displacement of the African plate against the base of the Plateau.
- Cordillera Penibética
- Cordillera Subbética
- Intrabético Groove
Guadalquivir Depression
The Guadalquivir Depression is a large triangular area open to the Atlantic Ocean, which is influenced by the sea. Among the forms of relief, the Guadalquivir depression offers a gently rolling landscape. Also, downstream from Seville, at very few altitude above sea level, lie the island marismas.
Balearic Islands
The Balearic Islands archipelago is the geographical extension of the Peninsula in the Mediterranean Sea via the Cape of La Nao, and, except for Menorca, represents the continuation of the Betic Cordilleras. The island of Mallorca, because of its size, best represents the original character of the relief. Menorca is different from the rest of the archipelago because of its links with the Andes.
Canary Islands
The Canary Islands, located in the Atlantic Ocean, have a volcanic character shared with other islands in the ocean itself. Their origin is related to volcanic emissions that occurred in the Tertiary Era. These include boilers and craters, rocks and badlands.
Cantabrian Coast
The Cantabrian Coast has a very straight coastal relief, coinciding with the axis of the Cantabrian mountain range and a great underwater fault. Protruding ends of Machichaco, Garlic and Peñas and small estuaries penetrate inside perpendicular to the shoreline.
Galician Coast
The Galician Coast falls mostly on the Atlantic coast, which, except for the section between the ends, provides a straight north-south orientation. Its main defining element is the existence of estuaries.
Andaluzian Atlantic Coast
The Andaluzian Atlantic Coast describes a turning angle to form the southern coast of Portugal. From the mouth of the Guadiana to Cape Trafalgar opens an oval that corresponds to the depression of the Guadalquivir.
Mediterranean Coast
The Mediterranean Coast includes the Betis area, the Gulf of Valencia, and the Catalan coast, which is home to the Ebro delta.