Fossil leaf beds
Original title: Jazigos de folhas
Describes fossil leaf beds in Madeira, notably at Ribeiro do Meio in the São Jorge valley, studied by Dr Heer, and a smaller deposit near Porto da Cruz possibly formed in an ancient lake.
Many years ago, at Ribeiro do Meio (‘middle brook’), on a slope of the São Jorge valley, at the same spot where lignite occurs, various layers of tuff and clay were found, one of which contained numerous leaves of dicotyledons and ferns. Dr Oswald Heer, who studied these leaves, recognised that they belonged to 25 species, among them the til (Ocotea foetens, Madeiran laurel), the folhado (Clethra arborea, a native tree), the tree heath (urze molar), the Madeira blueberry (uveira, Vaccinium padifolium), the tintureira and the myrtle.
In a light-coloured tuff to the west of the village of Porto da Cruz (‘harbour of the cross’) there are also some leaves and leaf impressions, perhaps belonging to Rubus Bollei and Carex pendula, as well as pieces of a soft, spongy wood.
When we come to speak of lignite, we shall return to the São Jorge deposit. As for the Porto da Cruz deposit, it may be supposed that it formed in an ancient lake, perhaps bounded by the islet in the bay, where the tuffs and sands accumulated that erosion later exposed.
In this article
Place
Places mentioned · 04
- Ilhéu do Porto da Cruz
Machico. May have bounded the ancient lake where the deposit formed.
An islet close to the Porto da Cruz coast, facing the small harbour. It may have bounded the ancient lake in which a fossil-leaf deposit formed.
- Porto da Cruz
Machico. Leaf impressions found in tuff west of the village.
North-coast parish created in 1577 and noted for good-quality wines. It was transferred from Santana to Machico municipality in 1852 and was the seat of a capitania-mor. It was also a fishing port where some sperm whales were landed.
- Ribeiro do Meio
Santana. Site of the fossil leaf bed alongside lignite.
A stream and locality in São Jorge parish known for its lignite deposits, which lie about 300 m above sea level. A fossil leaf bed occurs there alongside the lignite.
- São Jorge
Santana. Valley containing the Ribeiro do Meio deposit.
North-coast parish that was an original parish of Santana municipality and gives its name to the northern archpriest district. It is known for plant-fossil and lignite deposits studied by Heer and Bunbury, and for a 17th-century landslide. The Elucidário also describes its islet, headland, quay and stream.
People
People mentioned · 01-
Scientist who studied the fossil leaves of São Jorge and identified 25 species among them.