How is petroleum sold and distributed?

Question

How is petroleum sold and distributed?

Answer 1

The way everything else is?

Some petroleum is sold at auctions (on commodities exchanges), some is sold with long term contracts; some is sold for immediate delivery, while some is sold for future delivery (futures and long term contracts).

http://www.eia.doe.gov/pub/oil_gas/petro...

http://futures.tradingcharts.com/marketq...

http://in.reuters.com/article/asiaCompan...

Some is delivered by boat, some by pipeline, and some goes through both.

http://www.indiana.edu/~librcsd/etext/ho...

http://www.pipeline101.com/reports/Notes...