Patent ID: 9103944
Filing Date: 2015-08-11
Classification: B06B,E21B,G01V,H04R

Abstract:
1. A method for investigating cement bonding or rock formation structure near a borehole, comprising: generating a collimated acoustic beam by an acoustic beam source, the collimated acoustic beam having a frequency in the frequency range between approximately 15 kHz and 120 kHz; directing at one or more azimuthal angles and at one or more inclination angles the collimated acoustic beam towards a selected location in a vicinity of a borehole; receiving, at an acoustic detector comprising a two-dimensional array of receiver elements, an acoustic signal, the acoustic signal originating from a reflection, a refraction, or a surface wave propagation, or any combination thereof, of the collimated acoustic beam by a material at the selected location in an azimuthal angular range, each receiver element in the two-dimensional array of receiver elements being configured to receive a portion of the acoustic signal corresponding to a portion of the azimuthal angular range, the two-dimensional array of receiver elements being disposed on a surface of a cylindrical member and being spaced apart to provide a gap between neighboring receiver elements, the two-dimensional array of receiver elements comprising a piezo-electric film; analyzing the received acoustic signal to characterize features of the material around the borehole.