This is a Natural Geographic documentary that goes through the technology behind the oil platforms operating at depths of around 3000m which is currently testing the limits of human engineering both on practical and materials science aspects. The animations are excellent.
The doco is around 45 mins long however if you would like an overview in a shorter 18mins, watch the second video (it does have a minor editing glitch midway through part 2)
http://www.youtube.com/watch?v=xo6MpPemwZM