There are a lot of wrecked ships from many periods in time at the coast of Yamatai. Some of them are stranded in Shipwreck Bay. On the beach Lara can spot a relatively new life boat. As she soon afterwards discovers Sam's Pack we can assume that it is one of the Endurance's.
Shipwreck Bay is not an official title for this beach, but rather a name given to it by fans after seeing it for the first time in the Scavenger's Den Demo.