What is a Microatoll?

These structures have developed over long geological timescales. Their growth patterns provide high-resolution data regarding sea-level changes that occurred long after the extinction of the dinosaurs.

Extensive studies have been conducted on microatolls in the Mentawai Islands, which provide evidence of historical earthquake cycles.

Microatolls are colonies of massive corals, typically of the genus Porites, that exhibit a unique morphology characterized by a dead central surface and a living outer perimeter.

They are essential tools for paleoseismology and climate science, allowing researchers to reconstruct historical sea-level variations and tectonic uplift or subsidence.

The vertical growth of the coral is constrained by the lowest astronomical tide. When the coral reaches this level, the upper portion dies due to exposure, while the periphery continues to expand laterally, creating the characteristic 'atoll' shape.