2. Around 35 million-years (upper Eocene) the sea steadily reduced until it dried off. Therefore, evaporites (halite, potash and gypsum) precipitated in the most internal part of the basin. The thickness of the evaporites stratum is quite noticeable (1st map)
The gravel sedimentation persisted in Montserrat and Sant Llorenç del Munt (2nd map).