Publications

A reservoir characterization study has been applied on a Brownfield located in Sumatra, to improve accuracy of a geological model, using a newly developed procedure employing anomalous impedance and integrated geology, geophysics & reservoir, in order to locate potential remaining reserves. Seismic inversion was performed using both checkshot data and synthetic checkshot, and field division by blocks was identified through the help of variance cube maps. The seismic inversion produced anomalous impedance that was generated through cross-plot analysis could separate sand and shale better. Hence, by applying crossplot and statistical analysis between the anomalous impedance & petrophysical data obtained from well log analysis yielded a correlation between seismic and well data that will be used for facies modelling. Several realizations of facies modelling were overlaid with a bubble map of the field cumulative production to find the most realistic one. Eventually, a reservoir simulation was conducted to validate the model. A crossplot of density and impedance clearly shows separation between sand and shale that is very difficult to distinguish in acoustic impedance plot. A log P-impedance shale is introduced by converting the density into shale impedance, and the difference with the acoustic impedance results in anomalous impedance that indicates sand for high values. Good agreement results when the anomalous impedance is crossplotted with gamma ray and facies at the key well and other wells. Comparison with the previous study is presented, and suggests different facies distribution that is more realistic because the latter has better lateral resolution and is confirmed with the production history. Eventually, a reservoir simulation proves a reasonably accurate model. A newly-generated procedure geological modelling has been introduced using anomalous seismic impedance to improve accuracy of the facies modelling. The integrated GGR method could help more in reservoir simulation to validate the model becoming more realistic and implementable.