Any of a number of basic [[log|logs]] on which some aspect of formation resistivity has been recorded.

(1) Most resistivity logs derive their readings from 10 to 100 ft<sup>3</sup> of material about the [[sonde]]. See [[electrical survey]], [[laterolog]], and [[induction log]].

(2) [[microresistivity log|microresistivity logs]], on the other hand, derive their readings from a few cubic inches of material near the borehole wall.