Global oil markets are heading into uncharted territory. Opec, the cartel that oversees a third of the world's oil production, has dropped all semblance of control over the world's supply.Torn by a new war between its de facto leader, Saudi Arabia, and erstwhile rival Iran, the group failed to agree on a formal production target for the first time in its recent history in December.The "overriding impression is one of indecision and, to some extent, powerlessness" said oil analyst Jon Rigby at financial services company UBS."The group is not in control of the market or, indeed, its own production levels, and hence is largely irrelevant,"Life could prove nasty, brutish and short for investors and sovereigns burnt in the post-Opec oil world.This paralysis has led to a record glut in the world's oil supply and a price plummet not seen since the depths of the financial crisis in 2009. Current Opec production stands at around 31.5million barrels a day. With no official quota in sight, its 13 member nations are now intent on pumping as much as they can in a global free-for-all to capture market share and smash rival producers.Brent crude could now be heading to as low at $20 per barrel in 2016, according to Goldman Sachs.The result of the price crash could be a new deflationary wave hitting the world economy. On the upside, this record cushion should protect the world from adverse supply shocks, as geopolitical risks still loom large in Iraq and Syria. ..