Petroleum Systems Modeling — State of the Art and Future Directions
Research Consultant and Basin Modeler, Chevron Energy Technology Company, Houston
Petroleum systems modeling (PSM) is an integration of different geological disciplines to analyze the formation and evolution of sedimentary basins and to study processes such as generation, migration, entrapment and preservation of hydrocarbons. PSM estimates mechanical and chemical compaction of sediments and the resulting porosity/permeability, computes pressure, estimates source rock maturity and the degree of kerogen transformation, models multi-component hydrocarbon generation, expulsion and migration, provides likely locations where hydrocarbons are trapped, and estimates composition and volumes of accumulated hydrocarbons. In addition to its primary function, which is to help reduce exploration risk related to hydrocarbon charge, PSM has become very useful in prediction of pre-drill pressure and effective stress, which are utilized in reservoir and seal quality analysis.
Computational complexity of PSM depends on the quality and resolution of seismic and well input data, maturity of the project (exploration, development or production), availability of tectonic/structural/mechanical earth models, and availability of geochemical data. Typical models at present are not too large (several millions grid cells) and the subsurface is represented by relatively simple structured meshes. The utilization of structured meshes often results in inadequately represented internal model boundaries such as faults and may lead to incorrect hydrocarbon migration scenarios.
The availability of high resolution seismic and well data allows for building higher resolution and more complex models, spanning from seismic to nano, hence allowing for more accurate representation of complex features and processes. This requires incorporation of unstructured/adaptive meshes and also the utilization of algorithms that couple poromechanics, basin modeling, seismic data and inversion, and utilization of high performance computing platforms, e.g., GPU- or FPGA-based as well as optimized libraries for solving large, ill-conditioned, sparse matrices.
This talk presents the state-of-the-art in PSM and discusses recommended directions required for addressing future needs of exploration for conventional / unconventional resources and interactions with geomechanics and seismic.
AAPG Search and Discovery Article #90159©2012 AAPG Foundation Distinguished Lecturer Series 2012-2013.