CHEBYSHEV OPTIMIZED GEOPHONE ARRAYS

A theoretical discussion of Chebyshev arrays is presented which leads to useful and practical extensions of the previously published empirical expositions. It is shown that the wavelength (or, equivalently, the moveout) discriminating property of these arrays may be either quickly estimated or fully determined without the knowledge of the weighting parameters. Thus, the geophysicist may perform a great many “pencil and paper experiments” rapidly without the need to compute array weights, except when actually specifying a cable design. In addition, complex interrelationships between several tapered arrays are clarified, and, finally, a simplified, closed form equation for the array coefficients is derived, which has substantial computational advantages over the present high‐order polynomial expressions. To exemplify the use of the criteria and the equations introduced below, a sample array design is shown in some detail.