Extending the envelope of lwd acoustic measurements; reliable lwd acoustic data acquisition in shallow, unconsolidated formations and large borehole sections

Logging-while-drilling (LWD) is the preferred logging method in large boreholes and shallow unconsolidated formations, as the borehole condition in such formations deteriorates soon after drilling, and wireline data is thus adversely affected. This paper demonstrates the high-quality results of the latest generation of LWD sonic tool, in shallow, unconsolidated formations and large borehole size. The results enabled accurate wellbore analysis computation and prevented drilling problems while also delivering high quality data at high rates of penetration (ROP). Comparison with wireline results further clarifies the situation. © 2019, Taylor and Francis. All rights reserved.