Sedimentary rock

This is the oldest type of rock and was formed over millions of years by deposits of chalky mud and microorganisms. Such rock often contains the fossilised remains of marine organisms and we can date the rocks themselves by studying such fossils (particularly microfossils).

The sedimentary marine rocks visible on the surface of the Euganean Hills consist of a series of chalk and marl formations. The oldest sedimentary rock is red marly limestone (Rosso ammonitico, approx. 130 million years old), gradually followed by the formation of Biancone white limestone (up to approximately 90 million years old), and next, above the Biancone, a layer of Scaglia rossa pink limestone (from 90 to 55 million years old). The layers end with Euganean marl, a calcareous clay rock (just over 30 million years old).