Shape evolution of ooids: A geometric model

András A. Sipos, G. Domokos, Douglas J. Jerolmack

Research output: Contribution to journalArticle

6 Citations (Scopus)


Striking shapes in nature have been documented to result from chemical precipitation - such as terraced hot springs and stromatolites - which often proceeds via surface-normal growth. Another studied class of objects is those whose shape evolves by physical abrasion -The primary example being river and beach pebbles - which results in shape-dependent surface erosion. While shapes may evolve in a self-similar manner, in neither growth nor erosion can a surface remain invariant. Here we investigate a rare and beautiful geophysical problem that combines both of these processes; the shape evolution of carbonate particles known as ooids. We hypothesize that mineral precipitation, and erosion due to wave-current transport, compete to give rise to novel and invariant geometric forms. We show that a planar (2D) mathematical model built on this premise predicts time-invariant (equilibrium) shapes that result from a balance between precipitation and abrasion. These model results produce nontrivial shapes that are consistent with mature ooids found in nature.

Original languageEnglish
Article number1758
JournalScientific Reports
Issue number1
Publication statusPublished - Dec 1 2018

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Shape evolution of ooids: A geometric model'. Together they form a unique fingerprint.

  • Cite this