Andalusian & Catalan Coasts: A Geomorphological Study
Andalusian Atlantic Coast
The Andalusian Atlantic coast stretches from the Portuguese border to the Rock of Gibraltar and the Bay of Cádiz. Alluvial deposits from rivers have created low-lying coastal plains with small sand dunes, similar to those found along the coasts of Huelva and Cádiz. Ocean currents accumulate sand in places, forming littoral arrows (coastal formations built up from accumulated material resting on a rocky coast or island).
If these sandy formations run parallel to the coast, they form a coastal barrier.
Mediterranean Coastline
The Mediterranean coastline features a series of low-lying, straight stretches forming wide bays, separated by rocky headlands (e.g., Cabo de Gata, Palos). Characteristic features include small coves, beaches, lagoons, and tombolos.
The Mediterranean coast is divided into three parts:
Catalan Coast
The Catalan coast displays diverse reliefs: deltas, small coastal plains, rugged coastlines, and cliffs. The coastal mountain range meets the sea, forming cliffs and small bays, creating the distinctive landscape of the Costa Brava.
Gulf of Valencia
Extending from Cabo de la Nao to the Ebro Delta, this approximately 400km long coastal plain features beaches, marshes, lagoons, and tombolos.
Mediterranean Coast of Andalusia and Murcia
Stretching from the Strait of Gibraltar to Cabo de la Nao, this coast is characterized by the rugged relief of the Baetic Cordillera mountain range, along with features such as dunes and the lagoons of the Mar Menor in Murcia.
Catalan Geomorphology
Catalan relief is characterized by four main units: the Pyrenees (Pyrenean foothills and axial range), the Coastal Cordillera, the Central Depression, and the coastal plains. Catalonia’s mountainous setting includes two large plains and rugged terrain, such as the Empordà and Urgell plains, whose waters flow into the Ebro Depression.
The Pyrenees
Of the 435 km of the Pyrenees, 250 km lie within Catalan territory, extending from the Cinca River to Cap de Creus. They form two parallel mountain ranges:
Pyrenees Axial
This range, composed of older materials, features high-altitude plains, flat-bottomed ridges, and vertical walls.
Pre-Pyrenees
Dominated by folded sedimentary and limestone rocks. These ranges are divided into inner and outer ranges separated by depressions, such as the Tremp basin. Rivers flowing from the Pyrenees, due to steep slopes and hard materials, have carved gorges and canyons.
Coastal Cordillera
This range consists of a series of cross-reliefs along the foothills of the Pyrenees, forming tabular blocks (flat-topped relief with coastal borders). Some areas are elevated, while others are depressed, such as the Olot plain, which features over 40 volcanic vents.
Coastal Ranges
This mountain range runs parallel to the coast from the Ter River to the Ebro Delta. These reliefs are separated from the coast by inland depressions and faults. The section from Collserola to Gavarres features low-altitude, eroded mountains. The mountains south of Barcelona are sedimentary folds, predominantly limestone. Rivers like the Ebro, Llobregat, and Francolí cut through this relief. Rivers originating in these mountains, such as the Gaià and Besòs, are short due to proximity to the sea and have irregular flows. The range forms a pre-coastal alignment, with major peaks in the Montseny. Montserrat is an example of a relief formed by erosion-resistant conglomerates. The Littoral Range is gently undulating with no significant elevations, except for Mount Tibidabo and Collserola. Cliffs are found at both ends of the coast, such as in Garraf. A pre-coastal depression, formed by faults, lies between the two mountain ranges, encompassing La Selva and Penedès.