| abstract |
A new interpretation system receives a low resolution log and a high resolution log from a well logging tool that is disposed in a wellbore which traverses a highly laminated formation and generates an output record medium which clearly illustrates and quantifies each layer of the plurality of layers of the laminated formation. In response to receipt of the low and high resolution logs, the new interpretation system generates a rectangular deconvolved log. The rectangular deconvolved log is generated by first selecting a plurality of modes or possible formation types from a histogram. Each of the plurality of modes are then solved, in a least squares sense, by minimizing the sum, over a particular depth interval in the wellbore, of the square of the residual between the tool measurement and the reconstructed log, a calculation which is equivalent to solving a system of N equations and N unknowns. A basis function is determined for each mode, and the rectangular deconvolved log is defined to be the sum of the basis function for each mode multiplied by the calculated value of the associated mode derived from the solution of the N equations and N unknowns. The rectangular deconvolved log is subsequently convolved with a vertical response function of the well logging tool thereby producing a reconstructed log. The reconstructed log undergoes interactive refinement producing a refined rectangular deconvolved log. If no further refinement is needed, a volumetric analysis is performed on the refined rectangular deconvolved log to produce an output record medium which clearly illustrates and quantifies each layer of the plurality of layers of the laminated formation traversed by the wellbore. |