Purity: Burial Procedure When Dying on a Ship

Practical Laws of Islam as per the teachings of Ayatullah Sistani

Ruling 605:

If someone dies on a ship, in the event that the corpse will not decompose and there is no problem with it being on the ship, the people must wait until the ship reaches land and then bury it in the ground; otherwise, the ghusl, camphorating, and shrouding must be performed on the corpse while it is on the ship. After performing ṣalāt al‑mayyit, the corpse must be placed in a large barrel, the lid must be closed, and the barrel must then be thrown into the sea; or, a heavy object must be tied to the feet of the corpse and it must then be thrown into the sea. If possible, the corpse must be thrown in a place where it will not immediately become food for animals.

-Ayatullah Sistani, Practical Laws of Islam, Purification (Taharah)