Physical Simulation of Ultrasonic Imaging Logging Response

Area of Science:

• Geophysics
• Geological Engineering
• Non-destructive Testing

Background:

• Ultrasonic imaging logging offers potential for identifying subsurface geological features like fractures and holes.
• Limited physical simulation experiments hinder the field application of ultrasonic imaging.
• Laboratory-scale simulations are crucial for validating underground geological structure identification.

Purpose of the Study:

• To investigate the effectiveness of ultrasonic scanning for characterizing fractures and holes.
• To evaluate the influence of different fracture and hole parameters on ultrasonic pulse echo responses.
• To provide a reference for the field application of ultrasonic imaging in geological structure evaluation.

Main Methods:

• Conducted ultrasonic scanning experiments on a grooved sandstone plate and a simulated borehole.
• Utilized a combination of ultrasonic echo amplitude imaging and arrival time imaging.
• Analyzed the impact of fracture and hole characteristics on ultrasonic signal responses.

Main Results:

• Successfully identified fracture location, width, depth, and orientation using combined imaging techniques.
• Accurately calculated fracture dip angles, with evaluated parameters closely matching the physical simulation model.
• Determined that identification accuracy is linked to the ultrasonic transducer's radiation beam diameter.

Conclusions:

• Combined ultrasonic echo amplitude and arrival time imaging is a viable method for characterizing fractures and holes.
• Effective identification of single fractures requires width >= radiation beam diameter; multiple fractures require spacing >= radiation beam diameter.
• The study provides a foundation for improving ultrasonic imaging applications in underground geological assessments.