The Focused Electric Probe (LL3) has an current electrode is located in centre that is supplier constant potential and two rod electrode length is 152,4 cm located above (upper guard) and below (lower guard) of centre electrode. These are provides focused into the formation. Thickness of current bunch is related to the length of the electrode in the Focused Electric Probe. Thin current bunch provide of the increased sensitivity of the vertical reading; in short sensible reading can be taken from thin layer. The Focused Electric Probe is effected from condition of borehole less than other lateralog. The natural potential (SP) measuring apparatus is added on the probe.
Electrical measurement studies are executed with Focused Electric system that is manufactured by Robertson Geologging.