Apparatus, systems, and methods may operate to detect rugosity in a borehole. Additional activity may include generating a rugosity correction, responsive to detecting rugosity in the borehole, by finding an effective borehole diameter, consistent with the presence of rugosity, for which a simulation of a model of the borehole using the effective borehole diameter generates simulation resistivity measurements that match, within a tolerance, resistivity measurements before execution of a borehole correction algorithm. Additional activity may include applying rugosity correction by generating resistivity logs, using the effective borehole diameter, that are corrected for rugosity and borehole effect. Additional apparatus, systems, and methods are disclosed.