Ossa Morena Zone

The geology of the Iberian Peninsula consists of the study of the rock formations on the Iberian Peninsula, which includes Spain, Portugal, Andorra, and Gibraltar. The peninsula contains rocks from every age from Ediacaran to Holocene, and almost every kind of rock is represented. World class mineral deposits can also be found there.

The core of the Iberian Peninsula consists of a Hercynian cratonic block known as the Iberian Massif. On the northeast this is bounded by The Pyrenean fold belt, and on the southeast it is bounded by the Betic Foldchain. These twofold chains are part of the Alpine belt. To the west, the peninsula is delimited by the continental boundary formed by the opening of the Atlantic Ocean. The Hercynian Foldbelt is mostly buried by Mesozoic and Cenozoic cover rocks to the east, but nevertheless outcrops through the Iberian Chain and the Catalonian Coastal Ranges.

The Iberian Massif consists of rocks from the Paleozoic Era. It was assembled about 310 Ma. Several zones occur in the Iberian Massif. These were the pieces that were assembled to form the block. On the north coast of Spain occurs the Cantabrian Zone. Then to the west and also in the Iberian Chain and Catalonian Coastal Ranges is the West Asturian-Leonese Zone. Then the Central Iberian Zone appears near A Coruña, through the north of Portugal, and through the middle of Spain, including the Montes de Toledo. The Ossa-Morena Zone outcrops out to the east of Lisbon. This includes some Precambrian rocks. The furthest south part is the South-Portuguese Zone.

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