NRMS as Function of Non-Repeatability and Production Effects

G041 NRMS AS FUNCTION OF NON-REPEATABILITY AND PRODUCTION EFFECTS JESPER SPETZLER Dept. of Applied Earth Sciences TU-Delft The Netherlands Abstract The time-lapse normalised root mean squared (NRMS) function is explicitly expressed in terms of nonrepeatability (e.g. noise source wavelet variation and overburden function) and production effects. By looking for deviations in the NRMS value of different reflected wavefields in time-lapse common-offset gathers one can identify areas with possible 4D effects in the overburden function and at reservoir level. Introduction The time-lapse seismic signal is mostly a combination of non-repeatability (due to differences in acquisition and overburden function) and production effects