I'd say no, because:
#1: No group has claimed responsibility for the act (none that I know of)
#2: Very few people died, if it was a terrorist attack, they probably would've targeted a more vulnerable section of the rig.
However:
#1: The rig was sunk, if the terrorists objective was to do that, they succeeded
#2: Nothing was going wrong prior to the explosion.
#1: No group has claimed responsibility for the act (none that I know of)
#2: Very few people died, if it was a terrorist attack, they probably would've targeted a more vulnerable section of the rig.
However:
#1: The rig was sunk, if the terrorists objective was to do that, they succeeded
#2: Nothing was going wrong prior to the explosion.
