An estuary is an area where a freshwater river or stream meets the ocean. In estuaries, The salty ocean mixes with a fresh water river, resulting in brackish water. Brackish water is someone salty, but not as salty as the ocean. An estuary may also be called a bay, lagoon, sound, or slough.
Answer:
1. seawalls
2. volcanic
3. mass wasting
4. ocean basin
5. erosion
Explanation:
6. Reefs form from volcanic activity on an island in the ocean. This initially forms a fringing reef, but sea level rise can cause the reef to lie farther out from the island, forming a barrier reef. If the island ever subsides below sea level, the reef is called an atoll.
