What is the reason for pebble beaches vs. sand beaches?

Question

What is the cause for this difference? We were just in Croatia where they mostly have pebble/stone beaches and we were trying to understand what it the reason for this phenomena

Answer 1

Sand comes from erosion of rocks. If there are reefs off shores/around islands etc., then very little erosion of rocks/stones. This erosion takes many many years to occur. The tides, of course, cause the erosion.

Answer 2

To see a speeded up example of the way erosion turns big rocks, into little rocks and eventually into grit and sand try and have a look at a building site when the concrete mixer is being washed out to get the setting mix off the sides of the drum. Tthey'll throw in a few broken bats. ie broken half bricks, they'll tumble round in the drum with the water which is like the continual pounding of the waves and very quickly the brick pieces will be rounded off and get smaller, just an accelerated example of what nateure does. Now add the hardness of different rocks and the passion of the water to complete the picture.

Answer 3

Sand beaches used to be pebble beaches a very long time ago. As wave action crashes rocks and pebbles against each other, the grinding action reduces the pebbles to sand, but not in our lifetime.

If you saw a pebble beach as a young child, it would still be a pebble beach when you are old and wrinkled.

Answer 4

Sand beaches are older beaches. Pebbles and rocks are gradually broken down by the weather and the sea until they become sand. The larger the rocks on a beach the newer it is.

Answer 5

Don't know why there are pebble beaches and sandy ones, all I know is that dogs are generally allowed on pebble ones, which is great for our dog, as she loves the sea. Also if there is no sand, it generally means that there are no kids! No kids means no noise, and more importantly, NO FOOTBALL!!!

Answer 6

sand comes from the mountains as silt, and moves along. its more about wave action, and the speeds of the longshore current. In different seasons, the sand can get washed to sea, leaving a rocky beach during the winter and return in the spring.

Answer 7

Types of beach

Beaches differ in shape, according to the forces that created them: waves, tides and wind. They also differ according to the material available: mud, sand, iron sand, shells, cobbles, boulders, etc. Using photographs of beaches in New Zealand, it can be shown that each beach has its own characteristics that make it unique.

http://www.seafriends.org.nz/oceano/beach.htm#types