During the first step of the very rapid and large scale lowest Triassic transgression , we note in different areas (S Alps, Taurus,Turkey, S Armenia, E Elburz, Iran, Central Iran and Central
Afghanistan) the growth of domal stromatolites, thrombolites and other microbial structures. At the dawn of Triassic time, the carbonate factory was dominated by non-skeletal species and by microrganisms able to precipitate carbonate.