Gone setting

The setting of the story Gone is in a small town called Perdido Beach in Alabama, USA. What happened is that every person age 15 and above disappears suddenly, leaving only young children. A sphere forms around the town and some of the surrounding area. The whole of the first book is set inside of this where the kids need to survive. The area around the town includes a big beach that leads out to the sea where the ocean is suddenly cut off by the border. There is also a school for troubled kids called Coates Academy. There is also a surrounding forest not far from the town. Another important part of the setting is a big island that is discovered which used to belong to a wealthy couple with a big mansion on it.