Abstract
Depths of investigation have been measured for the following sondes: Compensated Formation Density (FDC*), Sidewall Neutron (SNP-:-), and two types of two-detector Compensated Neutrons (CNL *), namely the thermal tool (CNT-A) and an experimental epithermal tool (CNT-X). The mea- surement was carried out in a 35-percent-porosity laboratory sandstone formation.