Colorado Basin, Argentina: A Case Study Combining Forward Sedimentary and Petroleum System Models for Consistent Evaluation of Basin Evolution, Play Development, and Petroleum Migration and Trapping*
Guillaume Smagghe5, John Bunney5, and Romain Debarre6
Search and Discovery Article #40155 (2005)
Posted June 6, 2005
*Adapted from extended abstract, prepared by the authors for presentation, entitled “Combining Forward Sedimentary and Petroleum System Models to Consistently Evaluate Basin Evolution, Play Development, and Petroleum Migration and Trapping. A Case Study from the Colorado Basin, Argentina,” at AAPG International Conference & Exhibition, Cancun, Mexico, October 24-27, 2004.
1Beicip-Inc, Houston, TX;
2The Permedia Research Group Inc, Ottawa;
3Repsol- YPF, Argentina;
4Total, Paris, France;
5BP Exploration, Houston, TX
6Beicip-Franlab, Rueil-Malmaison, France
We present a multi-disciplinary approach to understand the basin-scale evolution of a continental margin petroleum system, using a reservoir modeling workflow as an analogue. Generation of a consistent description of geophysical, geological, and petrophysical dataset and understanding of their related uncertainty ranges is key in order to address the various scales of physical processes operating as the basin evolves. In our approach, we appropriately solve at different length-scales within the same geologic volume the numerical solutions of temperature, pressure, and petroleum migration back through time.
A deep offshore case study from the Colorado Basin (Argentine Continental Margin) (Figure 1), covering an area of 160,000 km2 is presented. We created a workflow combining integrated seismic stratigraphic interpretation, stratigraphic facies prediction, 3D basin modeling,and multiphase petroleum migration. Results from the study have enhanced our understanding of the geological evolution of the Colorado Basin with specific emphasis on the key risks on reservoir presence and petroleum system elements. It helped us to identify the variety of play-types and associated key risks within the basin.
Using the key interpreted seismic stratigraphic horizons, we generated the framework model by subdividing the stratigraphic section (Figure 2) according to zonations determined in wells and stratigraphic styles, and then evaluating both crustal and bathymetric evolution.
A numerical stratigraphic approach (Dionisos®) was used to predict the stratigraphic architecture and facies distribution (Figure 3) in the undrilled areas using macro-scale physical laws over geological times, taking into account the existing wells and seismic information as constraints.
The outputs of the stratigraphic simulation were used to populate a 3D basin model (Temis3D®). The dynamic evolution of the basin, including the compaction, pressure, temperature, and hydrocarbon generation, was calculated through time, and properties were calibrated against observed well data and offset analogues.
The evolving basin properties were then passed onto a high-resolution petroleum migration simulator (MPath®), which evaluates the migration and trapping of the expelled petroleum through time (Figures 4, 5, and 6). Stochastic uncertainty was introduced at this stage, allowing realizations of multiple scenarios in order to evaluate the distribution of pool sizes and petroleum phase types to be risked.
The workflow illustrated here combines the accuracy, refinement, and efficiency of three different numerical models and takes full advantage of the available data. Consistency of the geological and petrophysical descriptions and uncertainty are seen as keys to addressing the various scales of physical processes. Multiple scenarios constrained by available data were run to test geological hypothesis, such as 1) stratigraphy and facies distribution (source rock presence and type, reservoir presence and quality, seal capacity), 2) thermal regime, 3) charge access, and 4) migration pathways and efficiency.