Method and apparatus for smoothing measurements and detecting boundaries of features

摘要

A method and apparatus are described for removing noise by smoothing fine resistivity measurements made with a tool from inside a borehole penetrating an earth formation. Pixel values representative of the resistivity measurements are examined to determine the directions of features in the measurements and a smoothing of the pixel values is then made along the measured directions. The orientations of the features are obtained with a similarlity investigation of pixels in sub-array windows along parallel lines whose slope is varied. Optimal slope lines along which the pixel values in a window best resemble each other are determined as the direction of the features. Smoothing is done along the optimal slope lines. Substantially noise free pixel measurements are obtained to enable subsequent automatic signal processing such as the detection of edges between layers of different resistivity. The edges are recorded with an emphasis on a visual display for enhanced visual analysis.