| This paper, in accordance with the basis theoretical problems for natural gas exploration in deep-formation in the north of Songliao basin, according to the practical features, point out that gas source condition(gas-generating amount, gas-generating intensity, gsa-generating period) and reservation condition(cap rocks, faults, dissipation of natural gas) are main controlling factors determining accumulation of natural gas, and emphatically studied generation, dissipation and conservation of natural gas in geologic history to acquire objectively and rationally the resource amount of deep-formation natural gas on the basis of investigating the development of natural gas exploration theory and technology from home and abroad.In study of gas source condition, the quantitative dynamic evaluation of generation of natural gas and gas-generating amount are made on the basis of chemical dynamics. This work include: In order to demarcate chemical kinetic model inwhich organic matter generate oil and gas, constant velocity, rising temperature thermal modeling experiment is designed; In order to demarcate chemical kinetic model inwhich oil crack into gas, isothermic thermal modeling experiment inwhich oil crack into gas is designed ; In order to establish chemical kinetic model inwhich family constituents in oil (saturated hydrocarbon, arene, non-hydrocarbon,bitumen ) change into gas, isothermic or constant velocity jsothermal modeling experiment is designed. On the basis of above experiments, the chemical kinetic model inwhich organic matter of source rock of deep-formation in the north of Songliao basin primarily crack into oil or gas is established, which set up a basis for evaluating oil-generating amount, gas-generating amount of source rock of deep formation in different periods; set up the chemical kinetic model inwhich different qualities of oil and family constituents in oil secondarily cracked into gas, which provide theoretical foundation and practical methods for dynamic evaluation of gas-generating amount and oil-consuming amount in process of oil cracking. The geochemical features of source rocks in deep-formation of basins are systematically evaluated. Considered that the maturity of deep-formation source rocks is relative high and the practical tested geochemical index (remnant organic carbon, hydrogen index etc)can not objectively reflect the original abundance and original hydrocarbon-generating potential of organic matter in source rocks, original hydrocarbon-generating potential and original organic carbon of organic matter are restored from progressive recurrence using chemical kenetic models to calculate hydrocarbon-generating rate in this paper. The studied results illustrate that the restored hydrocarbon-generating potential of deep-formation in the north of Songliao basin is as 46 times as that of unrestored , and the original abundance is as 2.2 times as that of unrestored .On the basis of above studies, the hydrocarbon-generating profiles, hydrocarbon-generating history, hydrocarbon-generating intensity, hydrocarbon-generating amount in different periods and total up hydrocarbon-generating amount in deep-formation source rocks are systematically evaluated. The results illustrate that the present netoil-generating amount of deep-formation in the north of Songliao basin was calculated, being 67.76 X 10 t,oil-discharging amount 43.99 X 10 t , accumulative total gas-generating amount 74.27 X 10 m ,gas-discharging amount 62.30 X 10 m ,In study of conservation condition of natural gas , the sealing property of cap rocks and faults are discussed. On the basis of brilliant exposition of macroscupic and microscupic features of cap rocks of deep-formation natural gas in Songliao basin, the sealing capacity of cap rocks of natural gas in studied area is comprehensively evaluated, and creatively put forward a comprehensive cap rock-evaluating method using percolating velocity which natural gas pass though mudstone cap rocks. The evaluating results illustrate thatthe cap...
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