The Madeira Island originated more than 5,2 Ma ago with eruptions that occured due to the rise of magma from a Thermal Plume (hot-spot) located in the mantle subjacent to the African Plate Tectonics. The then formed island presented significant dimensions, whether in area or in altitude, but the weight placed over the oceanic plate by the volcanic material together with the material removal in depth caused the island sink.

It is possible to distinguish two different eruptive phases, the most ancient, designated as Ancient Volcanic Complex, that developed between 4,07 Ma and 2,55 Ma, and another more recent one, designated as Main Volcanic Complex, which occured between 2,19 Ma and 1,62 Ma.

The Ancient Volcanic Complex resulted from an effusive and explosive type of eruption, constituted by runoffs, cones and wide fields of pyroclasts, of all sizes, which is profusely cut by lodes. This volcanic complex is mostly covered by the Main Volcanic Complex, although, stratigraphically, it is not the unit that follows it.

The most ancient rocky outcrops corresponding to the Ancient Volcanic Complex are practically inexistent, yet the erosion caused by the riversides and by the sea sometimes uncovers rocks from this complex.

The Main Volcanic Complex occupies, whether in area and in volume, the most immersed part of the island, and its formation has been prolonged for a long period of time.
It is possible to distinguish two series that correspond to different eruptive phases, designated as inferior series and superior series.

The separation between the inferior series and the superior series is essentially morphological. The inferior Main Volcanic Complex outcrops in the Ribeira de Santa Luzia's top, Funchal, Ponta do Pargo, Fajã de Ovelha, Paul do Mar, Jardim do Mar until Calheta, Serra de Água, Curral das Freiras, Machico and Fajã da Nogueira. While the superior Main Volcanic Complex outcrops in all the island's Southern coast, from Ponta do Pargo to Caniçal, in the Paul da Serra's massif, in the Penha de Águia's top, Vale da Ribeira do Seixal, in the valleys of São Vicente e Boaventura, São Jorge, Santana, Porto da Cruz and also in the superior part of the Massif Central's peaks (Picos Ruivo, Areeiro, Cidrão and Gato).

Within the vast period of time ascribed to the Main Volcanic Complex, there might have been periods of volcanic dormancy, during which the present valleys might have formed. Data from absolute geochronology shows that the valleys were first carved in the northern coast and later on in the southern coast. This may be due to an early decline of the northern volcanic activity.

The last volcanic eruptions occurred between 0,12 Ma and 0,006 Ma, and were essentially in Funchal, Porto Moniz and Paúl da Serra. With the interruption of the island's volcanic activity, the erosion progressively lowered the relieves, deepened valleys and retreated cliffs, forming slopes, sedimentary landslides, alluvium and present beaches.

The Desertas islands are considered part of the same volcanic structure that originated the Madeira Island; a fact corroborated by the isobath of 100 m, which almost links the Ponta de São Lourenço to the Desertas islands.