Abstract:

Based on the analysis of light hydrocarbons in natural gas in the TabeiUplift of the Tarim Basin，obˉvious differences are found in the distribution characteristics of lighthydrocarbon in3types ofnatural gas:petroliˉferous gas，coalˉrelated gas and m ixed gas.For petroliferous gas，which is distributed in the Yingmaili low uplift and the Halahatang sag，relative contents of nˉalkane and nˉheptane are high;for coalˉrelated gas，which is disˉtributed in the Luntai fault uplift，relative contents of isoparaffin，methylcyclohexane and benzene are high;for m ixed gas，which is distributed in the Donghetang fault belt，relative contents of benzene，methylclohexane and nˉheptane are high.According to gasmaturity estimated using parameters such as carbon isotope ofmethane and the maturity of light hydrocarbon，we believe that（1）there were at least twoˉphases of poolˉform ing for natural gas in the Ti’ergen faultbelt，theYangtake faultbelt and theYingmai32buried hill structural zone;（2）natural gas in the Yingmai7fault belt，the Donghetang fault belt and the Yingmai2buried hill structural zone expeˉrienced oneˉphased poolˉform ing process;（3）parameters of light hydrocarbon reveal that natural gas in the western part of the Luntai fault uplift has features ofm igrating and charging from the Kuqa depression to the Tabei forebulge belt.

Key words: value of heptane, value of isoheptane, parameter ofMango, m igration direction, light hydrocarbon, natural gas, TabeiUplift, Tarim Basin