Keywords: 
• oils /
• si mulation /
• experiment /
• gas composition /
• gas yield /
• carbon isotope

Abstract: Hydrous pyrolysis experiments of generating gas from the mixture of oil- Water and reservoir rocks have been caried out in a closed system，the samples are derived from deep layer of the Songliao basin.the results show that yield Cuantities of gaseous hydrcarbon is very small at temperature below350℃，Which mainly derived from oil evaporation. when simulating temperature reaches 400℃，large Cuantities of gas are generated from oil. with increasing of temperature the proprtion of methane in the generated gas increases,While the heavier components decrease particularly the propane.the range of temperature for gas largely generated from the mixture of oil - Water sandstone is 450~500℃，While the range from the mixture of oil —Water and igneous rocks is 450~600℃. The Cuantities of gaseous hydrocarbon generated from both settings are similar and about 17m³/t oil at the end，but the hydrocarbon yield is different at each temperature point.the maximal yield at 5 Cis respectively 78.67m³/t oil abd 66.11m³/t oil for the two experiments hydrolysis and catalysis may be an important influence on the composition and yield of the simulated gas.the experiment also shows that δ¹³Cvalues of the gas generated from the experiment at temperature between 400~450℃(R_o approximately 1.3 % ~1.8 %)are relatively lower than that of gas derived from kerogen，and δ¹³C₁ is -5.86 %~-48.43 %. when the temperature increases to 550~600℃(R_o approximately 2.8 % ~3.4 %)，δ¹³C of the gas brcomes reativly higher than that of gas derived from kerogen，and kerogen，and δ¹³C₁ is -39.61 %~-24.26 %.this fact indicates that fractionation of carbon isotopon of gas from the experiment is stronger than the gas directly derived from kerogen.the regular sequence of carbon isotope has been found at temperature between 400~450℃Ci.e.δ¹³C₁＜δ¹³C₂＜δ¹³C₃＜δ¹³C₄.but partial opposites sequence of carbon isotope appeared at temperature above 500℃，the sequence is δ¹³C₁δ¹³C₂＜δ¹³C₃＜δ¹³C₄. Comparing the carbon isotopic composition between the mixture of oil- Water and sandstone and the mixture of oil- Water and igneous rocks，the latter is lighter 1.2 %~4.2 %than the fromer at the temperature of 400~450℃ and heavier at the temperature above 550℃，Which show a different influence of catalysis in various medium.this result is useful for identifying the origin and maturation of nature gas for the deep layer of the Songliao basin.