Definition and application of tight oil and shale oil terms

Based on a thorough literature investigation and a detailed analysis of the meanings and applications of the tight oil and shale oil terms,this paper compares their similarities and differences,and presents suggestions for a better understanding and application of the two terms.Though shale oil also refers to the crude generated through processing kerogen from shale rocks,both terms bear broad and narrow senses when used to indicate the oil from shale or shale-like formations.The current usage of the two terms can be summarized and described in the following three scenarios:(1)They refer to different kinds of unconventional resources,therefore are regarded as totally different from each other;(2)They are thought to be identical and are used alternatively;(3)They are different but also inherently connected.It is suggested that when using the terms,we shall follow the rule of "showing respect to customs and facilitating communications" and try to understand fully their connotations and extensions instead of only reading the lines.To tackle problems encountered during using or understanding the terms,we also shall adapt the policy of "continuous perfecting and timely modification" so as to achieve a more objective definition of the terms.Meanwhile,their international applicability shall also be taken into consideration.