Study on Feasibility and Location Method of Remote Detection Acoustic Reflection Imaging for Open Hole

Detecting and locating old open holes is a major challenge in petroleum engineering. Electromagnetic methods work well for casing wells but are ineffective for open holes, which require new technologies. Remote detection acoustic reflection imaging logging is a reflection imaging technology that has emerged in recent years. It can now image fractures and vugs within tens of meters near the borehole by processing reflected wave data from full wave signals. This manuscript aims to test the practicality of using acoustic remote detection technology to locate and detect open hole wells. A 3-D elastic wave time-domain staggered nonuniform grid with fourth-order accuracy in space and second-order accuracy in time utilizing the finite difference method was used to conduct a numerical simulation of acoustic remote detection of open hole wells. The simulation analyzes the wave field and imaging characteristics of open holes in sandstone and mudstone formations at various distances from the rescue well. This analysis concluded that acoustic remote detection technology can successfully be used for open hole detection. Based on the change law of reflected wave amplitude, a set of open hole detection and positioning technology is developed. The calculated results exhibit small distance errors compared with the model, enabling accurate location determination within 4–16 m near the well. Therefore, remote detection acoustic reflection imaging holds great potential for detecting and locating open hole wells.