Why do marine terraces form?

Marine terraces are terraced landforms that occur as elevated flats inboard of, and parallel to, coastlines. Outstanding examples of a stair-step landscape of marine terraces can be found in many places in the world. Marine terraces are formed by a specific geological process that incorporates erosion and by a buildup of coral.
Marine terraces are formed by a specific geological process that incorporates erosion and by a buildup of coral. The formation of marine terraces is controlled by changes in environmental conditions and by tectonic activity during recent geological times. Changes in climatic conditions have led to eustatic sea-level oscillations and isostatic movements of the Earth’s crust, especially with the changes between glacial and interglacial periods.

A marine terrace is a flattish area near the coastline. It is an erosional platform cut by waves. But, sea level has gone done relatively to the elevation of the platforms. Thus, the terraces are indicative of a tectonically active, emergent shoreline.

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