--> Monte-Carlo Modeling of Some Niger Delta Slope Events, by M. I. Oladapo, J. S. Ojo, M. O. Olorunfemi, and B. A. Adetola; #90037 (2005)
[First Hit]

Datapages, Inc.Print this page

Monte-Carlo Modeling of Some Niger Delta Slope Events

M. I. Oladapo1, J. S. Ojo1, M. O. Olorunfemi2, and B. A. Adetola3
1 Federal University of Technology, Akure, Nigeria
2 Obafemi Awolowo University, lIe-lfe, Nigeria,br> 3 Nigeria Petroleum Investment and Management Services, NAPIMS, Lagos, Nigeria

Monte-Carlo modeling has been utilized in this study to simulate seismic P-wave events on four horizons (AA, BB, CC and DO) in a Niger Delta Slope environment. This is aimed at generating AVO attributes. Monte-Carlo modeling undertaken on a well log from the Gulf of Mexico served as a generic model and control. Trend analysis regressions generated in the environment served as input for the models while Harvie-Braunsdrof (default parameter in SAVIOR) fluid method was used for establishing reservoir fluid properties. Fourier velocity served as velocity function. The results of the modeling are presented as AVO crossplots for brine sand (background), residual hydrocarbon and commercial hydrocarbon. For each event, offset-dependent synthetic seismograms are also generated using Previous HitZoeppritzNext Hit Previous HitequationsTop. The AA horizon is typified by incoherent orientations of AVO crossplots. The horizon is thus presumed unconsolidated. The synthetic seismogram generated shows no perceptible amplitude variation with offset on all the models. AVO crossplot of the encountered BB horizon show that most of the commercial hydrocarbon plots and some of the residual hydrocarbon plots fall on quadrant III (bright spot quadrant). Synthetic seismic generated for BB horizon exhibits positive AVO response (soft kick) on the commercial hydrocarbon model. A similar but marginal response was obtained on brine saturated BB model. Brine saturated model of the AVO crossplot for CC horizon model plotted mostly on hard sand quadrant. Conversely, presumed commercial hydrocarbon saturated CC is split between the hard sand and soft sand quadrants with low background normal values. The DO horizon is similar to the deep model of the Gulf of Mexico and hence exhibits similar crossplot. Curiously, high background normal (Bn) characterized residual hydrocarbon models while unconsolidated gas sand horizons exhibit anomalous characteristics.