【摘要】 由于印支不整合褶皱抬升,下扬子局部地区龙潭组被剥蚀,钻井揭示残余的龙潭组砂岩横向变化明显。岩心、测井和三维地震解释等综合分析表明,江苏黄桥地区龙潭组为向上变粗的三角洲前缘沉积序列,砂岩主要为三角洲前缘席状砂和分流河道沉积。测井约束波阻抗反演和孔隙度反演结果表明,较高波阻抗的砂岩平面上呈3个三角洲前缘朵状体展布。龙潭组砂岩平均孔隙度在4%～10%之间,平均孔隙度随现今埋深变浅而增大。更多还原

【Abstract】 Effected by the fold and uplift of the Indosinian movement,the Longtan Formation in the Lower Yangtze area was locally eroded.Drillings revealed that the lateral variation of the residual Longtan Formation sandstones had changed obviously.The comprehensive analysis of cores,log curves and 3D seismic interpretations showed that the Longtan Formation was a delta front sedimentary sequence,with the characteristics of coarsening-upward,and the types of sand body were mainly frontal sheet sand and distributary channel sand in Huangqiao area,Jiangsu Province.The results of logging constrained impedance inversion and porosity inversion showed that high-impedance sandstones spread in three delta front flower-like bodies in the plane.The average porosity of the Longtan Formation sandstones ranged from 4% to 10%,and became bigger as the present depth increasing.更多还原