Time lapse data driven low frequency model update

In this paper a method is described to update the low frequencies of the elastic parameters coming from pre-stack time lapse inversion in a data driven manner. In the process no assumptions are made regarding the nature of the reservoir changes. Also no assumptions are made regarding the relationships between elastic parameters or reservoir parameters. The method described here can be seen as a 4D extension to a 3D updating method described by Mesdag et.al. 2010. In this way independent measures are obtained of time lapse absolute P-Impedance and time lapse absolute Vp/Vs (or  and ). These can then be compared with propagation parameters derived from 4D time shifts or velocities.