弯曲模式波在各向异性井孔中传播的实验研究

EXPERIMENTAL STUDY OF THE PROPAGATION OF FLEXURAL WAVES IN AN ANISOTROPIC BOREHOLE MODEL

鉴于弯曲模式波在井孔中传播的基本原理，制作了用于模型井孔的单／偶极子换能器，在模拟硬、软地层的铝和有机玻璃的井孔模型中进行了测量，并与理论计算的频散特性作了对比．在声速各向异性的井孔模型中进行的测试表明．弯曲模式波在横向声速各向异性的井孔中，分裂为两种传播速度不同的快、慢弯曲模式波．实验结果表明，偶极子声波测井将能有效地探测地层的横向各向异性．

The basic principles and main properties of flexural waves propagating in a borehole are introduced.A mono/dipole transducer is made for laboratory experiments in borehole models.In order to simulate the hard and soft formation boreholes,measurements are performed with mono/dipole transducers in borehole models made of aluminum and lucite,respectively.Experimental results are compared with the theoretical dispersion characteristics.Measurements are also performed in an azimuthally velocity-anisotropic borehole model where the flexural wave splits into two flexural waves, fast and slow ones.The experimental results show that dipole acoustic well logging could be an effective means for surveying a formation's anisotropy.