Dictionary:Fig I-4

FIG. I-4. Induction log. (a) Schematic two-coil induction logging sonde. (b) Dual-induction log. IL_d is a deep induction log, IL_m a medium induction log. The separation of the resistivity curves shows a variation of resistivity with distance from the borehole, probably because of invasion. Laterolog-8 (LL8) and SP logs were run at the same time. (Courtesy Schlumberger.)