Towards a Common Earth Model: Combining Seismic Inversion with Basin Modeling

Kacewicz, Marek¹, Wenlong Xu² (1) Unocal Corporation, Sugar Land, TX (2) Unocal Thailand, Ltd, Bangkok, Thailand

Recent advances in 3D basin modeling include utilization of parallel algorithms for solv­ing classic Navier-Stokes equations and application of invasion percolation based methods designed for fast hydrocarbon migration modeling. These combined with the availability of excellent visualization tools and easy access to Linux clusters have opened a new era in data interpretation and integration. Basin modelers are able to handle much larger volumes of data which yield a higher model resolution and much better quality of final results.

One interesting advantage of being able to handle larger basin models is the opportuni­ty to utilize full 3D seismic inversion results. Another advantage is the potential for model­ing basin-scale hydrocarbon migration at reservoir-scale resolution. In addition to more reli­able temperature and pore pressure predictions resulting from better constrained rock prop­erties, it is possible to identify areas where calculated oil and gas saturations do not repro­duce well data. This most likely is an indication of some problems with input rock proper­ties. Saturation data generated by basin models can be utilized to improve seismic inversion. Multiple iterations between seismic inversion and basin modeling provide a foundation for a new approach in earth modeling, which may lead to more reliable final products.

This paper presents methodology and workflows for building integrated seismic inver­sion / basin models. Case studies from SE Asia and the Gulf of Mexico will be used to demonstrate this process and to evaluate the applicability of Navier-Stokes vs. invasion per­colation based methodologies in different geologic settings.