A Composite Seismic Attribute Used to Estimate the Sand Thickness for Thin Bed and Thin Interbed

Abstract

Summary Amplitude and frequency, known as two basic seismic attributes, are typically used to predict the layer thickness when its thickness is less than a quarter wavelength. For interbedded thin layer it is impossible to estimate the thickness of the single sand body from seismic attributes, and a realistic choice is to determine the calculative sand thickness. However, the relation between calculative sand thickness and seismic attribute is normally derived from a wedge model, which does not take into account the interferences of different sand bodies. When applying this relation to the interbedded thin layer, the estimation error is inevitably occurred. To improve the estimation accuracy, we have proposed a composite seismic attribute consisting of amplitude and frequency. Compared with conventional amplitude and frequency attributes, the new attribute has more linear relation with sand thickness for single thin layer and can be well responded to the calculative sand thickness variation for interbedded thin layer. The experiments on model data and real data verify the correctness and practicality of the new attribute.