Ichnofossils from Naturtejo Geopark

PENHA GARCIA ICHNOLOGICAL PARK

This important geosite of the Naturtejo Geopark is located on the northern slope of the village of Penha Garcia, where it includes the valley of the River Ponsul, formed by steep slopes of quartzite rock. The complex is part of Ramilo Mountain ridge, which is over 800 metres high and stretches all the way to the border at Termas de Monfortinho.

The UNESCO Naturtejo Geopark was the first to be created in Portugal. Although it covers a vast territory, the Penha Garcia ichnofossils stand out for their quantity, quality of preservation and ease of observation.

480 MILLION YEARS OF WILDLIFE IMPRINTED IN ROCK

In the Ichnological Park of Penha Garcia, the quartzite rocks of the Ordovician that we find here show fossil traces of the behaviour of marine life from 480 million years ago. These are mainly the traces left by trilobites, marine arthropods that fed on the shallow sandy bottom of the Rheic Ocean, located in the southern hemisphere and on the north-western margin of the Gondwana supercontinent. However, more than 60 species have now been identified in the fossils from Penha Garcia.

Of more recent formation, the Ponsul River’s epigenic slot was formed over the last 2 million years, aided by a series of tectonic faults. Throughout this deep valley, man built a large number of water mills which, taking advantage of the water’s power, grinded the cereals used to make bread.

THE LOCAL FAUNA

The valley is regularly flown over by some of the region’s most emblematic birds, such as the Griffon Vulture (Gyps fulvus), the Black Vulture (Aegypius monachus) and the Black Stork (Ciconia nigra). Upstream of the Ponsul river dam, in the reservoir area, you might catch a glimpse of the shy Heron (Ardea cinerea) or an Otter (Lutra lutra).

In the craggy areas we can see the Blue Rock Thrush (Monticola solitarius), the Cia (Emberiza cia) and the Rock Swallow (Ptyonoprogne rupestris).

THE FOSSIL ROUTE

The guided tour to the Ichnological Park takes in a circuit of around 3 kilometres, which starts in the centre of the village of Penha Garcia, explores the valley of the Ponsul River and returns to the same starting point.