Almost everywhere a change to dry land takes place: the sea gradually withdraws from southern Limburg. Extensive peat bogs develop, which at times become flooded by the nearby sea for short periods. The peat is now found as brown coal. The periods of flooding result in deposition of beds of silver sand. Fossil plants (palms and firs) indicate a tropical or subtropical climate. In northern Limburg only marine deposits are known from this period: sands with molluscs and corals. The latter are indicative of a warm climate too. Of note is the so-called Elsloo Layer: a highly fossiliferous bed.