摘要 |
Apparatus and systems, as well as methods, may operate to acquire formation signals from a deep measurement electromagnetic antenna array, where values of the formation signals depend on properties of a geological formation. Formation signals may also be acquired from an at-bit resistivity (ABR) sensor, where the ABR sensor comprises a drill bit electrically coupled to a toroid or to multiple electrodes, the electrodes separated by at least one gap. Further activities may include inverting the values of the formation signals to transform the values into an enhanced resistivity measurement for the geological formation, wherein the inverting comprises determining at least one of relative distance between layers of the geological formation, relative orientation of the layers to a housing, or a resistivity gradient of the layers, wherein the layers are not locally penetrated by the bit. Additional apparatus, systems, and methods are disclosed. |