When the roof of a coastal cave collapses, it forms
Answer Details
When the roof of a coastal cave collapses, it forms a geo. A geo is a narrow, steep-sided inlet, created when the roof of a cave erodes and collapses, and the sea fills the resulting hole. The collapsed roof is typically made of softer rocks, while the sides of the geo are composed of harder, more resistant rocks. The term "geo" is most commonly used in Scotland, but similar coastal features can be found in other parts of the world under different names, such as "sea cave" or "natural arch".