Explorer's Satchel
From WikiRaider
Explorer's Satchels are an Puzzle item in Rise of the Tomb Raider. They are left behind by deceased explorers, that travelled Siberia before Lara.
Explorer's Satchels are brown leather rucksacks that contain maps to Secrets; if collected, the reveal e.g. Survival Caches on the in-game map. They are similar in function to Monoliths and Archivist Maps.
They are not uncommon but often lie a bit off the beaten path and sometimes require Lara to take a detour to find them. Sometimes Lara will find the corps of a explorer right beside the satchel.