Abstract: Illustrative logging methods, systems, and software, provide for correction of cross-coupling error via a complex-plane extrapolation technique. Frequency-dependent measurements at each given borehole position will trace out a dependence of a quadrature signal component on the in-phase component. With linear or curve-fit extrapolation to the real axis, the cross-coupling error is readily compensated, enabling more accurate formation property logs to be derived over greater range of operating environments. The technique is particularly suitable for use with laterolog resistivity tools, where cross-coupling between current and voltage conductors might otherwise be problematic.

Abstract: Illustrative logging methods, systems, and software, provide for correction of cross-coupling error via a complex-plane extrapolation technique. Frequency-dependent measurements at each given borehole position will trace out a dependence of a quadrature signal component on the in-phase component. With linear or curve-fit extrapolation to the real axis, the cross-coupling error is readily compensated, enabling more accurate formation property logs to be derived over greater range of operating environments. The technique is particularly suitable for use with laterolog resistivity tools, where cross-coupling between current and voltage conductors might otherwise be problematic.

Abstract: A system based on a series of data accumulation hubs, connected together by high speed communication backbone for routing a limited number of data and power cables is suggested. Each hub is connected to arrays of sensor pods which contain the actual sensor elements and minimal, if any, interface electronics. Preferably, as many as 20 sensor pods can be connected to each single hub element wherein a system including five hub elements with 20 sensor pods each would comprise a 100 element array. The data from the individual sensors are accumulated in the hubs, buffered, and conditioned for transmission to the surface data acquisition system through the high speed metal backbone comprising multiple paths of transmission for redundancy in the event of failure. Provisions are made within each of the hubs so that if a hydrostatic leak were to occur, the fault can be isolated and the remainder of the system will function as designed.