Some of it has to do with the hardness of the rock. Sand is normally white or tan because silica is very hard and isn’t broken down easily. Black sands or green sands made of olivine are rare because olivine is softer and the sand gets broken down faster or swept away.
Wind speed.
Ice wedging. In areas without snow, it take longer to break down than areas where water gets frozen in cracks and expands as it cools, breaking up rocks.
It sims highly unlikely that a wave of that height can occur in the Atlantic Ocean, especially if we take the fact that the biggest ever recorded wave in the Atlantic is 95 ft. The big waves in the Atlantic are created by strong winds, and there's still no recording of a wind so strong that will be able to lift the waves to that heights. The only way that a wave that big can occur is if there is an tsunami, but since the Atlantic floor is pretty calm in that department it sims highly unlikely.
A mixed race. Especially an offspring of a Spaniard and an American Indian.
I hope this helped.
