On the enhancement of low frequencies in marine seismic data

Abstract

Low frequencies are most important in seismic imaging. They enhance the resolution, penetrate deeper and they are indispensable in impedance estimation. In this paper a fourstep approach for enhancing the low frequencies in marine acquisition and (pre)processing is proposed: 1) positioning the sources and detectors at the optimum depth, 2) carrying out proper deghosting and 3) (pre)processing the low frequencies separately. In step 4), the missing ultra-low frequency information (trend) comes from the velocity distribution and from modern gravity gradiometry.