What are the holes in the sand underwater beach?
What are the holes in the sand underwater beach? As the water sinks, it forces the air between the sand particles back upwards and this air bubbles out of of the sand, creating the effect we see in this picture, known as 'pin holes'.
Why is beach sand so fine?
For millions of years in the Gulf of Mexico and along the coast the constant grinding and pulverizing motion of the waves have broken down the sand. That creates a situation where the sand becomes so fine it doesn't take more than a small breeze to displace it on the beach. This is called “saltating”.