—stromatolitic /stroh mat'l it"ik/, adj./stroh mat"l uyt'/, n. Geol.a laminated calcareous fossil structure built by marine algae and having a rounded or columnar form.
* * *These structures are usually characterized by thin, alternating light and dark layers that may be flat, hummocky, or dome-shaped. Stromatolites were common in Precambrian time (more than 543 million years ago). Some of the first forms of life on Earth are recorded in stromatolites in rocks 3.5 billion years old. Stromatolites continue to form in certain areas today, most abundantly in Shark Bay in western Australia.
* * *▪ geologylayered deposit, mainly of limestone, formed by the growth of blue-green algae (primitive one-celled organisms). These structures are usually characterized by thin, alternating light and dark layers that may be flat, hummocky, or dome-shaped. The alternating layers are largely produced by the trapping of sediment washed up during storms on some occasions and by limestone precipitation by the blue-green algae on others.Stromatolites were common in Precambrian time (i.e., more than 542 million years ago). Some of the first forms of life on Earth are recorded in stromatolites present in rocks 3.5 billion years old. Although stromatolites continue to form in certain areas of the world today, they grow in greatest abundance in Shark Bay in western Australia. A matlike layer of blue-green algae is able to grow on the surface of sediments in the shallow waters there because evaporation causes high concentrations of salt that discourage snails and other organisms from eating the blue-green algae.
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См. также в других словарях:
stromatolite — ● stromatolite nom masculin Fossile du précambrien supérieur remontant à plus de 2,7 milliards d années. stromatolite [stʀɔmatɔlit] n. f. ou m. ÉTYM. Mil. XXe; du lat. stroma, stromatis « tapis », et lite pour lithe. ❖ ♦ Sc. Concrétion calcaire à … Encyclopédie Universelle
stromatolite — [strō mat′ə līt΄] n. 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… … English World dictionary
Stromatolite — Stromatolites (from Greek στρώμα, strōma , mattress, bed, stratum, and λιθος, lithos , rock) are layered accretionary structures formed in shallow water by the trapping, binding, and cementation of sedimentary grains by biofilms of microorganisms … Wikipedia
Stromatolite — Stromatolithe Un stromatolithe ou stromatolite (on parle aussi parfois de thrombolites ») est une roche calcaire ou une structure marine biogénique et organique laminée double couche. Les premiers stromatholites, fossilisés, datent de… … Wikipédia en Français
stromatolite — noun Etymology: Latin stromat , stroma bed covering + English o + lite Date: 1930 a laminated usually mounded sedimentary fossil formed from layers of cyanobacteria, calcium carbonate, and trapped sediment • stromatolitic adjective … New Collegiate Dictionary
stromatolite — (stro mah to laīt) Dome like microbial mat communities consisting of filamentous photosynthetic bacteria and occluded sediments (often calcareous or siliceous). They usually have a laminar structure. Many are fossilized, but some modern forms… … Dictionary of microbiology
stromatolite — noun A laminated, rock like structure built over geologic time by microorganisms such as cyanobacteria … Wiktionary
stromatolite — [strə(ʊ) matəlʌɪt] noun Biology a calcareous mound built up of layers of blue green algae and trapped sediment, especially as fossilized in Precambrian rocks. Origin 1930s: from mod. L. stroma, stromat layer, covering + lite … English new terms dictionary
stromatolite — stro·mat·o·lite … English syllables
stromatolite — stro•mat•o•lite [[t]stroʊˈmæt lˌaɪt[/t]] n. gel a laminated calcareous fossil structure built by marine algae and having a rounded or columnar form • Etymology: < G Stromatolith (1908) < NL stromat , s. of stroma stroma+ o o + G lith lith;… … From formal English to slang