Morgan Stanley analysts recently included this chart of crude production costs. Onshore Middle East oil sites are much cheaper to tap than North American shale, which costs about $65 per barrel to extract.
1. ponder-reflect deeply on a subject; I mulled over the events of the afternoon; philosophers have speculated on the question of God for thousands of years; The scientist must stop to observe and start to excogitate.
Synonym Discussion of perplex. puzzle, perplex, bewilder, distract, nonplus, confound, dumbfound mean to baffle and disturb mentally. puzzle implies existence of a problem difficult to solve the persistent fever puzzled the doctor.