Sims Castaway (PS2) HELP! Geyser Plains?

I think you need to have a stone hammer or better hammer as well as the chisel. Don't worry you won't run into any quicksand! The quicksand is in East River Plains. If you go to the Hidden Lagoon and find the portal to go to East River Plains you will be able to knock down a pillar to make a bridge across the sand. You will also find a map piece.