Hoping someone can help to clarify this for me

Chimera
MemberOvomorphApril 20, 2012942 Views12 RepliesIn the trailer we see what appears to be a dome shape open above the alien ship but further into the trailer we see the flat ground opening and Shaw running and jumping to keep from falling in the opening. It looks clear to me that one of the Temples are opening for the Alien ship to take off but what in the hell is the flat surface of the planet opening for??? If anyone has speculation on this, please enlighten me? Who knows, I may even be interpreting the events from the trailer wrong but that is how it appears to be playing out to me. thx