Ferida Má Cascades are located in Âncora river. The high slope early section of the waterfall is cut into the granite. After, the river crosses dozens of schist and quartzite layers with a different resistance to erosion (esq. A).

The alternation of rocks with different erosional strength gives rise to steps sometimes higher than 5 m (esq. B).

The most popular falls are also known as Pincho cascade, located along a succession of quartzitic layers.

At the cascades, erosion acts in particular at the top and bottom of the waterfall. At the top, the erosive action of the running water might lead to a retreat of the waterfall edge and the formation of rapids. At the bottom of the waterfall, the erosion caused by the falling water excavates "pits" that can originate small lakes (esq. C).

Ferida Má waterfalls are essentially due to lithological aspects related to the erosion resistance of

metamorphic beds, as well as their orientation. However, the shape and slope of the riverbed were also

influenced by sea level changes and tectonic uplift. The continuous increase in the difference of altitudes

between the mouth and the river source, due to sea level fall to continuing tectonic uplift of the continent

were a decisive factor in revitalizing the river erosion in the search for a new equilibrium profile (Fig. 1).

References:

Pereira, P; Henriques, R.; Brilha, J. & Pereira, D.I. (2019). Conteúdos científicos para a caracterização dos 8 monumentos naturais locais” enquadrado no projeto Geoparque Litoral de Viana do Castelo – 2ª fase. Município de Viana do Castelo, Relatório Final GEOSITE, 273 p.