Ooids (/ ˈoʊˌɔɪd /, [1] from Ancient Greek ᾠόν (ōión) 'egg stone') [2] are small (commonly ≤2 mm in diameter), spheroidal, "coated" (layered) sedimentary grains, usually composed of calcium carbonate, but sometimes made up of iron - or phosphate -based minerals.

Oolite or oölite (from Ancient Greek ᾠόν (ōión) 'egg stone') [1] is a sedimentary rock formed from ooids, spherical grains composed of concentric layers. [2] Strictly, oolites consist of ooids of diameter 0.25–2 millimetres; rocks composed of ooids larger than 2 mm are called pisolites.

Jul 1, 2024 · Ooids are concentrically-laminated, sedimentary grains produced through successive stages of carbonate precipitation and abrasion that typically form above wave base in tropical-to-subtropical carbonate platforms (e.g., Davies et al. (1978)).

Mar 1, 2019 · Ooids are spherical or ovoidal carbonate grains (typically <2 mm in diameter) of smooth, well-laminated cortices that accrete around a nucleus, typically a bioclast, peloid, siliciclastic grain or lithoclast (Fig. 1).

Aug 30, 2019 · Ooids, pisoids, oncoids and pelloids comprise the most common non-skeletal component of limestones. The first three are characterized by enveloping laminations that range from perfectly concentric spheres to strongly asymmetric grains.

Coated grains include oolites, pisolites, oncoids, and oncolites. oolites (figure below) are formed by a series of concentric layers surrounding a nucleus. They generally form in agitated marine environments including tidal sand bars or tidal deltas between barrier islands.

Jan 29, 2018 · Here we investigate a rare and beautiful geophysical problem that combines both of these processes; the shape evolution of carbonate particles known as ooids.

Ooids are small rounded accretionary mineralized bodies. They could be called sand grains, but they are no ordinary sand grains. Just like normal sand grains, ooids have a diameter reaching up to 2 mm (usually less than 1 mm).

Common ooid nuclei are peloids and fragments of Halimeda, red algae, and mollusks. You might find these chapters and articles relevant to this topic. Most Upper Jurassic reservoirs are developed in ooid grainstones that originally had porosities of nearly 50%.

Ooids are spherical-subspherical grains, consisting of one or more regular concentric lamellae around a nucleus, usually a carbonate particle or quartz grain. Sediment composed of ooids is referred to as an oolite.