Acoustic logging-while-drilling tools having a hexapole source configuration and associated logging methods

摘要: Multipole acoustic logging-while-drilling (LWD) tools and associated methods are disclosed herein. In some embodiments, the LWD tool comprises a transmitter array at least one receiver array. The generates waves with an excitation pattern having cutoff frequency greater than about 3 kHz. is spaced apart from configured to detect said waves. Some of method embodiments comprise: generating multipole in fluid-filled borehole using kHz; selectively detecting that propagate pattern; determining shear wave slowness for formation penetrated by borehole.