Reverse Time Migration: A Seismic Imaging Technique Applied to Ultrasonic Data
نویسندگان
چکیده
INTRODUCTION New fast and efficient multi-channel ultrasonic echo measurement systems are currently introduced for practical applications in NDT-CE [ 1, 2]. The acquired multi-offset data are currently processed and imaged by the synthetic aperture focussing technique (SAFT, see e.g. [ 3, 4]). The application of SAFT, which is closely related to the seismic Kirchhoff migration method, is successful in many cases, but has certain limitations. For example vertical or steeply dipping interfaces as well as lower parts of a tendon duct are normally not visible in SAFT images (Figure 1). Recent developments of the SAFT technique as phase evaluation have resulted in improved imaging results and reflector characterisation possibilities [ 5] but the basic limitations still exist.
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