Analysis of Abnormal Logging-While-Drilling (LWD) Curves During Horizontal Well Steering

In the later stages of oilfield development, exploration and development targets are becoming increasingly complex, with a growing number of horizontal wells, 3D sidetrack wells, and extended-reach wells. The existing logging operation techniques are unable to fully meet the demands of increasingly challenging operations while maintaining efficiency. As a result, logging-while-drilling (LWD) technology is being applied more frequently. Given the characteristics of the F oil reservoir in Block X, which features relatively thick single sand bodies and prominent effective thickness of individual layers, it is suitable for the deployment of large-scale horizontal wells. Compared to vertical wells, although the principles of logging remain the same for high-angle and horizontal wells, most instruments are influenced by factors such as well inclination and formation dip, leading to “anomalies” and “distortions” in the measured curves. Under these circumstances, it is essential to understand the logging response characteristics of high-angle and horizontal wells. During the steering process of horizontal wells, the use of logging-while-drilling (LWD) can effectively balance efficiency and benefits. By promptly identifying curve anomalies during LWD and integrating various data and methods such as mud logging, geosteering, sedimentary facies maps, seismic attributes, and seismic inversion, abnormal issues can be efficiently and swiftly addressed.