1. adj. [Formation Evaluation]
Referring to a type of conventional electrical log in which the current-emitting and the current-return electrodes (A and B) are placed close together on the sonde, with the measure electrode (M) several feet away and the measure return (N) far away. This arrangement is sensitive to the potential gradient between A and B. The spacing is defined by the distance from M to the midpoint between A and B. The most common spacing is 18 ft, 8 in. [5.7 m]. The lateral gives a sharper response to a bed boundary than a normal but also introduces several artifacts that can give misleading results.