BOOM!! A stomatolite here, a stromatolite there.....

Calcium Carbonate (limestone) stromatolite
  •  sedimentary environment more tectonically stable than the greenstone belts  of the Archean 
  • rate of sedimentation lower than Archean, and provided the broad, shallow, photic, and non-predator environment that stromaotlites needed to enter the rock record 
  • these sites were also the sites of evolution of shelf invertebrates in the later phanerozoic 
During the Proterozoic stromatolites became abundant and widespread.  Their morphologies ranged from unbranching columns, conical structures, domes, spherical balls, planar and wavy laminated structures, as well as in the from of large reefs.  It was during this time that stromatolites reached their peak and maximum diversity.