What is the liquid that Ronan comes out of in his introduction?

When Ronan makes his spectacular and violent appearance on Guardians of the Galaxy, he comes out from a covered hole fill with some sort of liquid. He is in this liquid hole in the foetus position.

Knowing that this hole is completely fill and sealled shut:

1. 
   

   What is this liquid and how can he survive in that ?

   
   


2. 
   

   To add a bit more, why does he get covered in sand before being clothed ?