sentences:  Towards the end of the Paleozoic radiolarites formed also along the southern margin of Laurasia near Mashad in Iran.During the Triassic (Upper Norian and Rhaetian) cherty, platy limestones are deposited in the Tethyan region, an example being the Hornsteinplattenkalk of the Frauenkogel Formation in the southern Karawanks of Austria.They are composed of interlayered cherts and micrites separated by irregular, non-planar bedding surfaces.