Physical geography: relief, geology and landforms of Spain and Castilla y León
Domain 1 asks you to read the relief of Spain and of Castilla y León as the outcome of a geological sequence rather than as a list of names. Questions typically ask you to place a landform inside its structural unit, to order events in time, or to explain why the northern Meseta looks as it does.
The structural skeleton
- Hesperian Massif: Precambrian and Palaeozoic granite, slate, quartzite and gneiss, folded by the Variscan orogeny and later fractured. In Castilla y León it surfaces in the west (León, Zamora, Salamanca) as peneplain surfaces, granite tors and fracture lines now followed by rivers.
- Alpine ranges: Pyrenees, Cantabrian Range, Iberian System, Betic Cordillera. The Sistema Central is a set of Hercynian basement blocks re-elevated along faults during the Alpine cycle, not a fold belt.
- Sedimentary basins: Duero, Ebro and Tajo, filled during the Cenozoic with continental conglomerates, marls, clays and limestones; the Duero leaves Spain through the Arribes canyon.
Relief units of Castilla y León
Submeseta Norte at roughly 700–800 m; Montes de León; Cordillera Cantábrica (Torre Cerredo, 2 650 m); Sistema Ibérico (Moncayo, Urbión); Sistema Central (Almanzor in Gredos, 2 592 m); and the Duero fill, organised into páramos (limestone), campiñas (clays and marls), fluvial terraces and rañas on the western margin.
Landform families
Glacial cirques and moraines in Gredos, Picos and Urbión; karst at Cañón del Río Lobos and Ojo Guareña; fluvial gorges and terraces; granite berrocales and block fields.
Worked example
A landscape at about 800 m shows a gently undulating surface cut by narrow gorges, thin stony soils, granite outcrops aligned NW–SE and no folded strata. Reasoning: the altitude and flatness point to the Submeseta Norte peneplain; the granite identifies Hercynian basement, not basin fill; the NW–SE alignment matches the Alpine fracture set reactivated by incision; the absence of folds means the surface postdates the Variscan deformation. Conclusion: a fractured Hercynian peneplain, not a young mountain range.
Traps
- Placing the Sistema Central in the Iberian System, or describing the Meseta as a mountain range.
- Calling the Duero basin a rift: it is a Cenozoic sedimentary basin.
- Ignoring the Portuguese stretch of the Duero and the Arribes.
- Treating páramos as glacial or volcanic features.
- Attributing the Cantabrian Range to the Variscan orogeny alone.