The Džbán rock tower

The Džbán rock tower can be found in Vranov, at the foot of Ralsko, and this rock formation is evidence of the original Mesozoic submarine sedimentation, i.e. the deposition of sandy material on the seabed. Sedimentation took place in the Mesozoic, specifically in the Middle Turonian. On the rock we can observe alternating positions of sandstones with layers of siltstones. These layers also produce an interesting variety of yellow, ochre and red hues. The red colouration is caused by iron minerals, specifically limonite and hematite.

The rock also shows evidence of ancient life – if you look closely, you will see ichnofossils – fossil traces of biological activity. In scholar circles, these are called colonisation horizons. Here they occur in the form of interlocking, horizontally deposited, thin, tube-like formations, and are classified in the genus Thalassinoides.