oncolite

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Related to Oncoids: Peloid, Ooids

oncolite

[′äŋ·kō‚līt]
(geology)
A small, variously shaped (often spheroidal), concentrically laminated, calcareous sedimentary structure resembling an oolith; formed by accretion of successive, layered masses of gelatinous sheaths of blue-green algae.
References in periodicals archive ?
Microherms grew by expansion of grounded oncoids and tuberoids.
This unit contains oncoids, echinoderm ossicles (including spines), bivalve fragments, tuberoids containing renalcid species A, ostracode valves, intraclasts, Parafavreina, and quartz silt.
Oncoids contain peloids but no skeletal microfossils.
Mound growth was initiated within the euphotic zone when water energy decreased to a point at which oncoids ceased to roll frequently and became microherms.
In SEM images, oncoids and Rothpletzella accumulations floating in the matrix are built by tubes filled with sparitic cement (Fig.
Oncoids in the overlying facies II correspond to type A of Ratcliffe (1988), indicating their formation in a moderately agitated environment.
Oncoids as environmental indicators in the Much Wenlock Limestone Formation of the English Midlands.