渤海湾盆地垦东地区新近系断裂特征及其控藏作用

摘要

利用基础地质、钻、测、录井及三维地震资料，结合相干分析技术，对渤海湾盆地垦东地区断裂几何学和运动学特征进行了研究，在此基础上分析了断裂对成藏要素的控制作用。结果表明，研究区主要发育NNE、NEE、NWW走向断裂体系，受郯庐断裂早期活动影响，研究区断裂活动具有古近纪“西强东弱”、“南强北弱”，新近系“西弱东强”、“南弱北强”的特点。不同成因类型断裂对成藏要素的控制作用不同，拉张型断裂主要形成简单断块型圈闭，张扭（扭张）型断裂形成复杂断块和断层—岩性圈闭，压扭型断裂形成背斜构造圈闭；断裂对储层的控制，表现在储集砂体临近张性断层、远离扭性断层发育的一般规律；拉张型、张扭（扭张）型断层和压扭型断层封闭性依次增强，油气一般在封闭性较强的油源断层附近富集。%We studied the geometric and kinematic characteristicsof faults in the Kendong area of the Bohai Bay Basin, and analyzed their controls on hydrocarbon accumulations, based on basic geology, well drilling, testing, logging and 3D seismic data. The study area mainly developed on NNE, NEE and NWW oriented fracture sys⁃tems. Affected by the early activity of Tanlu Fault, faulting in the western and southern parts of the study area was stronger than that of the eastern and northern parts in the Paleogene, but the reverse in the Neogene.Differ⁃ent types of fractures had different controlling functions on hydrocarbon accumulation elements. Tensile fractures mainly formed simple fault block traps, transtensional( torsion) fractures formed complex fault block and fault-lithological traps, and compresso-shear fractures formed anticlinal structural traps. Reservoirs controlled by faults generally followed a principle that sand bodies developed near extensional faults and away from torsion faults. Sealing of extensional faults, transtensional ( torsion ) faults, compresso-shear faults enhanced in order, and hydrocarbon usually accumulated near the oil source faults with better sealing conditions.