Abstract:

The characteristics of saturated hydrocarbons and n alkane hydrocarbons of reservoir core extracts and crude oil in Yaha oil and gas fields in Tarim Basin are analyzed and studied systematically in this paper,the results show similarities in n alkane distribution,biomarkers distribution and their combined characteristics of saturated hydrocarbons as well as geochemical characteristics of aromatic hydrocarbons for tar mats,oil sand,asphaltic sandstone and crude oil.These characteristics suggest that hydrocarbons of these samples originated from the same source rocks.However,geochemical characteristics of tar mats reveal that the formation mechanism of tar mats is the intrusion of gases which results in the deposition of asphaltene in crude oils.