a rocky mass consisting of layers of calcareous material and sediment formed by the prolific growth of cyanobacteria: such structures date back to Precambrian times
Derived forms
stromatolitic (strəʊˌmætəˈlɪtɪk)
adjective
Word origin
C20: from Greek, from strōma covering + -lite
stromatolite in American English
(stroʊˈmætəˌlaɪt)
noun
a laminated, sedimentary rock structure formed primarily in Precambrian shallow pools by mats of sticky, blue-green algae, which trapped layers of silt, esp. of calcium carbonate: these wavy or round formations serve as evidence for dating the first life forms on earth and are still being produced today