Azimuthal shear-wave anisotropy measurement in a borehole: Physical modeling and dipole acoustic verification.

An anisotropic physical model is constructed to evaluate the anisotropy measurement. The model consists of a series of equally spaced thin limestone slab sheets cemented with concrete, resulting in a transversely isotropic medium. For the anisotropy measurement evaluation, the borehole model is tested by a standard multipole acoustic tool. The measurement finds an S-wave anisotropy magnitude about 20% and determines the fast S-wave polarization along the alignment direction of the slab sheets. The results of the work not only validate the borehole measurement technology, but also provide a testing facility for calibrating the measurement acoustic tool.