On the estimation of local slopes

Abstract

Current time-processing algorithms often are based on one-parameter or multiparameter coherency analysis (semblance) schemes applied to the data. Such procedures, besides being computationally expensive, lead to significant uncertainties in the searched parameters. Conventional semblance methods can be avoided for a number of imaging tasks if local slopes can be extracted directly from prestack data—for example, by filtering schemes. Although the idea is not new, it has revived for various purposes, such as velocity analysis, [Formula: see text] imaging, migration to zero offset, and time migration. We propose a simple, straightforward correction to linear plane-wave destructors based on the observation that in addition to the local slope, its inverse can be extracted from the data in a fully analogous way. Combining the information of both extractions yields a simple yet effective correction to the local slopes. The naive application of linear plane-wave destructors with our correction produces high-quality results, even with a high noise level and interfering events.