A numerically intense geological database that describes the physical and chemical conditions of the Gulf Coast Basin is assisting the scientists of the Global Basins Research Network to understand the processes that control the movement of oil and gas in sedimentary basins. By visualizing the data scientists are able to observe sedimentary conditions that would otherwise take much longer to investigate. This image depicts the various structures beneath the ocean flow in an area off the shore of Louisiana. Two faults are shown, in addition to three geographic layers: (from bottom) top-of- salt, shale, and sand and shale.
High performance computing plays an important role in the recovery of non-renewable energy resources. About two-thirds of the U.S. energy supply comes from oil and gas, and although much oil continues to be imported, there are profound advantages to domestic production: for example, ensuring a stable supply and price to the consumer. While most large U.S. oil reservoirs have already been discovered, two-thirds of the oil still remains in old fields after conventional recovery technology has been applied. Enhanced oil recovery (EOR) using advanced technologies has the potential to recover another 100 billion barrels worth about two trillion dollars at today's prices.
Domestic oil and gas producers are working with scientists from other sectors to optimize recovery methods for existing petroleum reservoirs. Petroleum industry scientists use reservoir simulations run on high performance computers to determine the production potential of reservoirs and the most efficient methods to extract petroleum resources before investment in field operations is made. The simulations model large complex field problems quickly, accurately, and efficiently, leading ultimately to reduced recovery costs. Research projects combining the expertise of researchers from universities, industry, and government focus on ways to improve reservoir simulation methods for flow through porous media, pore- scale multiphase flow, and hydrocarbon migration. As a technological spin-off, EOR simulation can be applied to remediation strategies for underground, contaminated sites.
New parallel algorithms for computational models describing the flow of oil and other organic chemicals in porous media are an important technical development. Models employ stochastic and conditional simulation and take into account numerous variables associated with reservoir behavior caused by complex physical and chemical phenomena. Parallel algorithms help researchers utilize the computational power of massively parallel computers to perform the simulations. Researchers are also writing parallel versions of two widely used reservoir simulation codes, UTCHEM and UTCOMP. UTCHEM has been applied to study both surfactant EOR and surfactant remediation of ground water contaminated by dense nonaqueous phase liquids found at weapons sites and other locations.
This figure shows a comparison between the computed injectivity of carbon dioxide and field data from an oil reservoir in Texas operated by Texaco, Inc. The University of Texas compositional reservoir simulator UTCOMP was used to make this calculation. The capability to predict the rate at which carbon dioxide can be injected into these old wells to increase the oil production from the field is crucial for the economic success of such enhanced oil recovery operations. This comparison shows close agreement with the field data from a geologically complex San Andres formation.
To better understand and predict the interactions between fluids and rock, field simulation programs must extrapolate results from laboratory samples. To assist in interpreting experimental results, researchers are developing a basic theoretical framework for multiphase flow systems that incorporates current knowledge of displacement processes and the understanding of oil and rock chemistry. One technique in this framework, the Lattice-Boltzmann method, is essential for solving Navier-Stokes equations, the basic equations of fluid flow. These equations are the basis of the mathematical models that simulate the movement of a multiphase system of organic materials through rock pores.
Scientists are developing computer visualizations to chart fluid movements below the ocean floor of the Louisiana coast. Observations in this area are providing new insights into how over- pressured oil and gas move in sedimentary basins. Because the study area encompasses the largest oil field in the continental United States, these insights may have important economic consequences. Researchers are developing visual models that reflect changes in temperature, pressure, and strata of sand and shale to allow qualitative evaluation of the rate of fluid flow required to produce these changes.