Method for Conditioning the Reservoir Model on 3D and 4D Elastic Inversion Data Applied to a Fluvial Reservoir in the North Sea

Andersen, T.¹, K. Hatland¹, Trond Hoye¹, F. Liestol¹, G. Mangeroy¹, Hilde C. Meisingset¹, C. Otterlei¹, Eli Zachariassen¹, Art Jan Wijngaarden² (1) Norsk Hydro, Bergen, Norway (2) Norsk Hydro Research Centre, Bergen, Norway

A work flow to improve the modeling of a fluvial reservoir is presented. Modeling of fluvial reservoirs can be very uncertain when only conditioned to well data. By utilising 3D and 4D seismic inversion data to condition the geological model, the uncertainty in the facies distribution is reduced. Cross plot of 3D elastic inversion data predicts facies better than acoustic impedance data or Vp/Vs data individually. By including 4D elastic inversion data, the correlation between the classified facies from seismic and the facies zonation in the wells, is further improved. A sand probability cube is computed from 3D and 4D elastic inversion data, and used to condition the geological model of the fluvial reservoir. Upscaling and flow simulation are carried out on a set of realizations. This results in a range of simulated production profiles. The dynamic information I the 4D seismic is then used to rank the realizations by comparing the real 4D data with forward modeled elastic parameters from the flow simulation model.