Jim Redden M-I L.L.C. Drilling Fluids Houston, Texas For help in preparation of this article, thanks to Ted Bornemann and Lindsay Fraser, Houston, Texas, USA; Amy Bunger and Robert Elphick, Denver, Colorado, USA; Mike Grace, Dallas, TX; Didier Largeau, Patrick Perrin, Jay Russell and Patrick Vessereau, Clamart, France; Stephen Prensky, Silver Spring, Maryland, USA; and John Rasmus and Don Williamson, Sugar Land, Texas. ADN (Azimuthal Density Neutron), ARI (Azimuthal Resistivity Imager), BorDip (automatic dip computation software), CMR (Combinable Magnetic Resonance), ECS (Elemental Capture Spectroscopy), ELAN (Elemental Log Analysis), Formation MicroScanner, FMI (Fullbore Formation MicroImager), GeoFrame (system software), GeoSteering (instrumented steerable positive displacement motor), GVR (GeoVISION Resistivity sub), MDT (Modular A new measurement device delivers high-quality borehole images in oil-base