Apparatus and methods of determining formation resistivity

摘要

APPARATUS AND METHODS OF DETERMINING FORMATION RESISTIVITY Abstract In various embodiments, apparatus and methods are provided to determine formation resistivity associated with a well. Measurements taken using sub-arrays of a tool at different distances of investigation can be used to determine formation resistivity, where the sub-arrays are arranged to make azimuthal related measurements. Separations readings related to resistivity can be generated from signals received from different directions and can be analyzed to characterize validity of a measurement reading. Additional apparatus, systems, and methods are disclosed. Control Unit 111-N Transmitter or 120 sReceiver 117-* Transmitter or Receiver 102 --7/ 0 111-2 Transmitter or Receiver 111-1 Transmitter or 120 Receiver Data Processing L Unit Fig.1