How can uplift turn a coral reef into a coral island?

Uplift transforms a coral reef into a coral island through crustal movements that raise the reef system above sea level.1

When these geological forces elevate the previously submarine reef top, it emerges as a low, plateaulike feature. Unlike islands formed by accretion—which are built from accumulated storm debris and sediment—uplifted islands are typically rocky and composed of the original reef structure.1

Once exposed, these islands undergo significant transformation through subaerial processes:
* Weathering: The land surfaces are sculpted by solution weathering, often creating karst topography, cliffs, and rugged, pitted terrain.1
* Erosion: Surface runoff and erosion can create a prominent rim and a saucer-shaped interior. If the original reef was an atoll, the central lagoon may become a shallow or completely dry interior basin.21
* Case Hardening: Alternate wetting and drying of the exposed limestone can cause recrystallization, leading to hardened, knifelike edges.2

The Aldabra Islands serve as a notable example of this geological origin.1