Geological applications using an electrical micro imaging tool

The resistivity micro imaging tool introduced by Halliburton produces electrical images that are being used in a variety of geological applications. The tool is a microresistivity-type imaging device with six independent articulating arms extending from the main body.Each arm is mounted with a pad containing a 25-electrode scanning array. The EMI tool and all other micro imaging devices measure changes in resistivity along the borehole wall that correspond to subtle changes in rock composition, grain texture, and fluid properties. High-end graphics software processes the data to produce highly visual 2D and 3D images of the borehole. The paper describes the use of this tool in fault analysis, fracture analysis, rock texture, strata dip analysis, and thin-bed analysis.