No, not screenshots. Sorry.

GGL Wire has interviewed journeyman actor Brad Hawkins, who is motion capture work for Doom 4. Among the host of things Hawkins revealed about the process was this little tidbit:
Hawkins: But I do know we are dealing with a post war/post apocalyptic event that civilians and military are fighting for their survival.
This lends even more weight to the idea that Doom 4 will be set on Earth.

Follow to GGL Wire for the full interview and mo-cap production shots.