Improvements in recording device to investigate the properties of the Earth formations surrounding a Borehole

摘要

A well logging apparatus and method is disclosed which can be used as a wireline logging device or technique, and is also suitable for being employed in a logging-while-drilling device. Electromagnetic energy having primarily a transverse magnetic mode component is guided along a tubular conductor in a borehole, and measurements of the transverse magnetic mode component can be used to obtain the conductivity and/or dielectric constant of formations surrounding the borehole.