Pragosa – viewpont

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The top of Pragosa is the highest point of the so-called Alqueidão da Serra depression. This one, triangular in shape and open to the north, is essentially carved out on little benches of calcareous and marls from the Upper Jurassic arranged in an anticlinal fold of great amplitude, orientated N-S. Its limits correspond to two important tectonic accidents. To the west, the fault of Rio Maior - Porto de Mós, which is very wide in this region and filled by marl sediments rich in evaporite rocks of the Lower Jurassic, and to the east the limit of this depression that is quite abrupt with the fault escarpment of Reguengo do Fetal oriented according NNE-SSW and tilted to the W. This accident was the main responsible for the depression, as it operated as a normal fault during the distensive periods of the Jurassic and later at the end of the lower Cretaceous, was reactivated in left detachment with a strong normal component.

From this place you can enjoy a panoramic view of the Alvados depression, on the Alvados escarpment fault that limits it to the west, from the Castelejo area to Castelo de Alcaria and on Fórnea stream. Castelo de Alcaria corresponds to an imposing escarpment resulting from an inverse movement of a fault associated with that of Alvados. To NW you can see the north top of Candeeiros mountain and on the coastal platform.

Anticline - fold convex upward in which each half of the fold dips away from the crest.

Cretaceous – last phase of Mesozoic Era, between 135 and 165 million years.

Depression – landform sunken or depressed below the surrounding area.

Evaporite - mineral or rock deposited directly from a solution (commonly seawater) during evaporation. For example, gypsum and halite are evaporite minerals.

Fault –cracks in the Earth's crust where movement occurs on at least one side.

Fold – formed when one or several originally flat and planar surfaces, such as sedimentary beds, become bent or curved as a result of plastic (e.g. permanent) and ductile deformation.

Jurassic - geological period in which the dinosaurs dominated and the development of vegetation was abundant. It lasted about 54 million years, roughly between 208 to 144 million years ago.

Limestone – sedimentary rock composed of calcium carbonate.

Marl - sedimentary rock with a carbonate and a clay component in more or less equal parts.

Tectonics - study of rocks deformation that make up the Earth's crust and the forces that produce such deformation at a global scale.

Thrust - formed by horizontal compressive stresses and so cause shortening of the crust. Since the hangingwall moves up relative to the footwall, most of these faults place older rocks over younger ones.