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Related to Ooids: Oolitic limestone, OOIDA


See oolith.

[o(o)- + -oid.]
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To investigate, he and Halevy turned to tiny ovoidal grains - ooids - composed of fine concentric layers of ancient iron oxides.
The state of finite strain was calculated for the Ambar Formation, using elliptical ooids and quartz grains.
Photosynthesis may shift carbonate solubility enough to promote the precipitation of these minerals, which induces the formation of irregular ooids, disseminated grains, cementation in specific laminae, early diagenetic dolomite, etc.
Small pebbles containing (casts of) goethitic ooids. These probably originate from the Estonian 'Linsenschicht', dating either from the Lower Kunda Stage ([B.sub.III]) or the Lower Aseri Stage ([C.sub.I]a).
The majority of allochems in the matrix are made up of micritised ooids and peloids forming a poorly sorted assemblage of medium to coarse sand grade matrix (Fig, 10B, 10C), Other minor allochems consist of superficial ooids, coated, disarticulated and abraded shell fragments.
Found mostly in shallow tropical seas like the in Bahamas, the ooids are a rare occurrence in the coastal waters of the Arabian Gulf.
This limestone is principally composed of ooids, carbonate spheres that usually form in tropical beach environments, illustrated by the cross section shown in Figure 3a.
GA also contains light-brown phosphatic ooids. The rock contains accessory amounts of zircon, tourmaline, garnet, rutile, calcopyrite and glauconite, whereas corundum, amphiboles and disthen have been preserved in Western Estonia [22].
The presence of diagenetic goethite / haematite as cement or as coating of zoned and goethite- ooids showed a highly oxygenated and warm shallow water environment (Wenk and Bulakh, 2008).
Garner, "Occurrence of Dolomite Beds, Clasts, Ooids and Unidentified Microfossils in the Coconino Sandstone, Northern Arizona" (paper presented at the annual meeting of the Geological Society of America, Portland, OR, October 18-21, 2009), http://gsa.confex.com/gsa/2009AM/finalprogram/ abstract_161247.htm (accessed June 6,2010); J.
However, the presence of ooids suggests that the water depth may not have been great, unless the ooids were transported from shallower depths.