detail of the rocky coastline

alga algae aquatic away beach bedrock cave cavern cliff cobble cobblestone cost crust down encrustation erode eroded erosion flint foreshore formation geological geology granite grotto hole hollow karst layer limestone marble nook outcrop pebble pothole puddingstone rock rocky sand sandy scale scaling sea seaboard seaside seaweed sedimentary shore stack stone stony tidal tide tideland tidemark tidewater tideway water waves weatherbeaten weatherworn worn