英语翻译The term oil field is also used as a shorthand to refer to the entire petroleum industry,however,it is more accurate to divide the oil industry into three sectors:upstream (crude production from wells and separation of water from oil),midstream (pipeline and tanker transport of crude) and downstream (refining and marketing of refined products).

英语翻译
The term oil field is also used as a shorthand to refer to the entire petroleum industry,however,it is more accurate to divide the oil industry into three sectors:upstream (crude production from wells and separation of water from oil),midstream (pipeline and tanker transport of crude) and downstream (refining and marketing of refined products).