Stromatolites are layered sedimentary formations created by the growth of microbial mats, particularly cyanobacteria. These structures are significant in paleontology for understanding the early history of life on Earth, the formation of oxygen in the atmosphere, and the conditions of early marine environments.
Source Awramik, S. M. (1971). “Precambrian Stromatolites: A Bibliography.” Geological Society of America Memoir 135.