The helicopter landing on the rig gives a sense of proportion and the size of the rig. View the image large and you will see the helicopter at the right hand end of the rig. The vessel to the right of the rig, I believe to be a barge. It also must be quite large. notice the smaller vessels scattered about in the image. I understand they are installing a brine diffuser for a new desalination plant on the Gold Coast, Currumbin, Queensland, Australia.
The image was captured just before sunrise.
Nikon D40x on auto handheld.