The practice of deep oil and gas exploration in the southern Songliao Basin shows that volcanic oil and gas reservoirs have become an important field for oil and gas breakthrough.In recent years,the degree of oil and gas exploration for volcanic rocks has been significantly improved.The basin has abundant drilling,seismic,logging,volcanic rock chronology and geochemical data,which provides conditions for the study of deep volcanic rocks in the basin.Volcanic rocks in Songnan area have the characteristics of wide distribution,large thickness,complex lithology and lithofacies,and time-lapse of strata.Stratigraphic sequence division is the basis of geological research,which is of great significance for subsequent related geological research and oil and gas exploration and development deployment.In addition to the previous methods of lithology and lithofacies identification and seismic stratigraphic contact relationship analysis,this study also used U-Pb,K-Ar,Ar-Ar dating methods to determine the geological period of volcanic rocks under the guidance of volcanic chronology.Through sampling analysis and testing,130 age data of volcanic rocks in Songliao Basin are obtained,and the age of volcanic rocks in Songnan area is clarified.Further combined with the classification of volcanic rock composition,the volcanic rocks of Huoshiling Formation in Songnan area develop three eruption cycles,from top to top,they are neutral eruption cycle,intermediate-acid eruption cycle and intermediate-basic eruption cycle.The distribution range of neutral eruption cycle is wide,and the number of eruptions is large,which is developed in Chaganhua area,Lishu area and Longfengshan area.The distribution range of intermediate-acidic eruption cycles is small,and the thick-layer acidic effusive facies is dominant,and the volcanic channel facies is developed,which is mainly distributed in the Chaganhua and Lishu areas.The distribution range of the intermediate-basic eruption cycle is small,and it is only developed in the Dongling area.The cycle is dominated by intermediate-basic effusive facies and intermediate-basic explosive facies.The division of volcanic eruption cycle of Huoshiling Formation in southern Songliao Basin is clarified,the stratigraphic framework of volcanic rocks in the whole area is established,and the eruption cycle which is more conducive to exploration and deployment is selected to carry out research work,which controls the time cost of exploration and is conducive to the study of volcanic rocks in southern Songliao Basin.
万方数据
维普
