Web1 de nov. de 2012 · Ooids, mainly calcareous, spherical to subspherical coated grains consisting of one to several nearly concentric cortices encrusting a nucleus, are ubiquitous features of (sub) tropical oceans... After being buried under additional sediment, these ooid grains can be cemented together to form a sedimentary rock called an oolite. ... (Wilson et al., 2024). The formation of the ooid cortex around the test or shell protects it from abrasion, fragmentation and bioerosion. Ver mais Ooids (from Ancient Greek ᾠόν (ōión) 'egg stone') are small (commonly ≤2 mm in diameter), spheroidal, "coated" (layered) sedimentary grains, usually composed of calcium carbonate, but sometimes made up of Ver mais Whether ooids become calcitic or aragonitic can be linked to strontium/calcium substitution within the crystalline structure. … Ver mais There are several factors that affect ooid growth: supersaturation of the water with respect to calcium carbonate, the availability of nuclei, agitation of the ooids, water depth, and the … Ver mais • Ooid Formation at the Wayback Machine (archived 20 June 2013) Ver mais An ooid forms as a series of concentric layers around a nucleus. The layers contain crystals arranged radially, tangentially or … Ver mais Ooids with radial crystals (such as the aragonitic ooids in the Great Salt Lake, Utah, US) grow by ions extending the lattices of the radial crystals. The mode of growth of ooids with tangential (usually minute needle-like) crystals is less clear. They may be … Ver mais Sometimes fossils are included in ooids, often forming the nuclei. This taphonomic process is termed ooimmuration (Wilson et al., 2024). The … Ver mais
Modern carbonate ooids preserve ambient aqueous REE …
WebOoid shoals, sedimentary structures consisting of carbonate grains, are often used as proxies to explore changes in seawater chemistry over Earth history. WebIn summary, ooids can be a reliable proxy for REE + Y characteristics of ambient surficial waters when adopting suitable analytical methods, including laser ablation, that allow the identification and isolation of a contamination signal from siliciclastic detritus. doi:10.1016/j.chemgeo.2024.01.015 fatcat:7lmrs363afcrxhhq4mlmjvt6j4 Open Access candy chief officer
Giant Induan oolite: A case study from the Lower Triassic Daye ...
WebRecently, organomineralization has been identifi ed as a key process for the initiation of freshwater ooid cortex formation, but the exact biochemical mechanism (s) involved and subsequent... Web16 de out. de 2024 · Ooids are spherical to sub-spherical carbonate grains characterized by an internal nucleus, surrounded by a cortex of concentric laminae, with diameter between 0.20 and 2.00 mm (Simone 1980; Flügel 2004 ). Ooids are accretionary in nature; they grow by the progressive addition of cortical layers. Web1 de set. de 2008 · The microbial role in the formation of the cortex of low‐Mg calcite freshwater ooids in western part of Lake Geneva in Switzerland has been … fishtank theater kansas city