Schlumberger

AIT Array Induction Imager Tool

Shallow to deep resistivity logs: Determine true resistivity and identify the invaded zone

The AIT array induction imager tool generates resistivity logs from measurements made simultaneously at five different depths of investigation (DOIs)—10, 20, 30, 60, and 90 in. The differences between the curves enable accurately characterizing the shallow invaded zone and determining true resistivity, Rt, from deep measurements. Multichannel signal processing delivers robust, stable tool responses with enhanced radial and vertical resolution, and environmental effects are corrected for. Because all of the DOIsare logged by the AIT tool using a common measurement principle, the responses of impermeable zones closely match for easy identification.

Resistivity logging in water- and oil-base muds

The AIT array induction imager is the most commonly deployed electric log in freshwater muds. In combination with accurate formation porosity logs, the AIT tool’s resistivity measurements enable quantifying water and gas saturation.

In wells drilled with oil-base mud, the invasion signature on logs from the AIT tool is reduced if the filtrate is the oil component of the mud rather than the water component. Although the resistivity contrast between filtrate and the formation fluid may be diminished, logging with the AIT tool also provides insight into the downhole behavior of oil-base mud systems.

Combinability for rig-time savings

The innovative through-wiring of the AIT tool enables running it with other logging tools above and below. Bottom-only tools, such as the FMI fullbore formation microimager and dual-dipmeter tools, can be run in combination with an induction log. In addition to significant rig-time savings, combining tools reduces depth-matching problems that could obscure correlation.

Related services and products

 
Request More Information

AIT Tools for Standard, Slim, Hostile, and HPHT Wells

AIT tool configuration
PrevNextZoom1 of 1