Final answer:
Fjord estuaries are formed when a glacier-carved valley is flooded by the ocean. These estuaries can typically be found in areas that have experienced glaciation.
Step-by-step explanation:
Fjord estuaries are formed when a glacier-carved valley is flooded by the ocean. These estuaries can typically be found in areas that have experienced glaciation, such as Norway and Alaska. As the glacier retreats, it creates a deep, narrow valley that is later filled with seawater. The combination of the deep valley and the influx of seawater creates a fjord estuary.
For example, in Norway, the Sognefjord is a famous fjord estuary that was created by glacial activity. The Sognefjord is 204 kilometers long and is the longest fjord in Norway.