The panel's survey of multidisciplinary research on sedimentary basins demonstrates a broadening beyond the traditional questions of identifying and extracting nonrenewable resources. By preserving a record of vertical motions of the lithosphere through time, sedimentary basins provide unique leverage for reconstructing the geodynamic history of Earth. Because of growing interest in environmental issues and global climate change, sedimentary basins also have become the crux for studies of interactions among the solid Earth, its hydrosphere, atmosphere, and biosphere. At the same time, important practical concerns regarding the quality of water resources and the disposal of industrial wastes are shaping the future of research on the hydrologic properties of basins. Minerals and fossil fuels are still important research issues, but there is a growing effort to integrate these questions into a more comprehensive agenda for basin research.
To address these problems, there has been increasing interest in multidisciplinary research strategies for basin studies. For example, research teams of geologists, geophysicists, geochemists, and petroleum engineers are now common throughout the petroleum industry. Industry-academic-government consortia have combined modeling, fieldwork, and laboratory measurements to develop an unprecedented understanding of subsurface fluid-rock systems. And scientists from diverse fields such as
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--> 3 Conclusions and Recommendations The panel's survey of multidisciplinary research on sedimentary basins demonstrates a broadening beyond the traditional questions of identifying and extracting nonrenewable resources. By preserving a record of vertical motions of the lithosphere through time, sedimentary basins provide unique leverage for reconstructing the geodynamic history of Earth. Because of growing interest in environmental issues and global climate change, sedimentary basins also have become the crux for studies of interactions among the solid Earth, its hydrosphere, atmosphere, and biosphere. At the same time, important practical concerns regarding the quality of water resources and the disposal of industrial wastes are shaping the future of research on the hydrologic properties of basins. Minerals and fossil fuels are still important research issues, but there is a growing effort to integrate these questions into a more comprehensive agenda for basin research. To address these problems, there has been increasing interest in multidisciplinary research strategies for basin studies. For example, research teams of geologists, geophysicists, geochemists, and petroleum engineers are now common throughout the petroleum industry. Industry-academic-government consortia have combined modeling, fieldwork, and laboratory measurements to develop an unprecedented understanding of subsurface fluid-rock systems. And scientists from diverse fields such as
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--> mantle geodynamics, oceanography, sedimentology, stratigraphy, paleontology, and hydrology are working together to study and interpret the historic record of geologic processes stored in sedimentary basins. The panel believes that continued efforts to encourage such collaborations among a wide range of geoscientists is a critical goal for strengthening basin research in the future. Today, multidisciplinary research on sedimentary basins is focused on understanding and predicting basin formation within the framework of plate tectonics and mantle convection; hydrocarbon generation and migration during basin evolution; present and historic fluid flow and chemical transport; changes in basin fill and thermal evolution with the tectonic environment; spatial and temporal variations of subsurface porosity; and the record of tectonics, climate, and sea-level change preserved in sedimentary basins. Developing a broad research agenda for basin studies will be important because there is considerable overlap among these topics. For example, predicting hydrocarbon formation and migration requires information on porosities and thermal and tectonic histories. Models of fluid and chemical transport depend on the distribution of rock types in a basin as well as the variations in porosity. Models of basin formation utilize a broad range of information to constrain the historical record of subsidence, fill, and chemical evolution. And patterns of subsidence through time help constrain geodynamic theories of Earth behavior. Because of these interrelationships, advances in one research area may rely on advances in distant fields. For example, accurate interpretations of the paleo-oceanographic record in sediments may require advances in the subsurface visualization of basins obtained through reflection seismology and high-performance computing. Similarly, hydrologic flow models could be improved through enhanced understanding of fault distributions and rock properties in basins. Future basin research will also be challenging because of the extreme heterogeneities of basins and basin materials over a range of length scales from the micron scale of the mineral-fluid interface of a particular grain to variations in sequence stratigraphy over distances of hundreds of kilometers. Moreover, geologic observations document that
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--> basins form in many different tectonic settings (Figure 1). This complexity suggests that accurate modeling of basin processes will require extremely fine spatial resolutions; large volumes of observational constraints derived from subsurface, field, and laboratory measurements; and a comprehensive understanding of the physical and chemical processes governing basin formation and evolution. As is common in the study of complex systems, the greatest challenge of this work will be to generalize modeling results to develop unified understandings and theories (e.g., Kauffman, 1993). To this end, the panel makes the following recommendations. Development of a Comprehensive Set of Basin Models The panel believes that there should be focused effort to develop a comprehensive set of models for studying the origin and evolution of sedimentary basins. In detail, such models would improve the understanding of diverse processes such as fluid flow along fractures, the history of mineral and fluid reactions with basin subsidence, and the record of global climate change preserved in basin materials. Linked together, such models would contribute to a new integrated understanding of sedimentary basins with broad implications for research across the geosciences, for identifying and extracting mineral and fossil fuel resources, and for preserving the quality of vital water resources for society. Strategies for this modeling effort should focus on improved characterization of basin materials over all length scales; strengthened efforts to collect and archive subsurface data on sedimentary basins; refined theoretical understanding of the processes that modify basins through geologic time, including mantle convection, subsurface porous flow of fluids, and the thermodynamics of reactions among fluids, minerals, and biomass at depth, and synthesis and linking of existing models to form a comprehensive yet flexible set of models for describing the formation and evolution of sedimentary basins.
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--> Supporting this effort will require innovative funding mechanisms that emphasize collaboration among federal agencies, industry, and the academic community and link existing disciplinary research programs related to sedimentary basins. As an example, the panel believes that there would be significant benefit in establishing collaborative programs among the National Science Foundation and the U.S. Department of Energy's Office of Fossil Energy and Office of Basic Energy Sciences, with appropriate liaison with efforts by the U.S. Geological Survey (USGS) in basin research and relevant programs of the National Aeronautics and Space Administration, National Oceanic and Atmospheric Administration, and Environmental Protection Agency. Such an effort would strengthen communication among industry, government, and academic scientists and would enhance the dissemination of subsurface data collected by industry through drill cores and reflection seismology. Data for Basin Research Basin models are critically dependent on accurate and complete data sets describing the subsurface environment. Petroleum companies have recognized the economic value of such information and have spent billions of dollars over the past 40 years collecting reflection seismic data, well cores, borehole logs, and production data from oil fields. While much of this information is still proprietary, there has been recent interest in releasing, preserving, and archiving much of these data partly because of the great value for a wide range of applications beyond petroleum geology. These include environmental protection, waste disposal, water resource management, global change studies, and seismic hazard mitigation. There has also been concern that these data may be lost through the process of corporate downsizing and from degradation of the storage media (e.g., magnetic tapes). To address these problems, the American Geological Institute (AGI) has initiated a project to establish a national system of publicly available repositories for data from the oil and gas industry (termed the National Geoscience Data Repository System). This project has identified data sets that corporations would transfer to the public domain for such a repository (approximately 25 percent of the reflection seismic data and 50 percent of the well cores collected in the United States). Detailed planning for this effort is under way. At the same time, the Shell Oil
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--> Company has donated its core and sample repository to the Bureau of Economic Geology at the University of Texas. These data were obtained from wells in 40 states and include 670 km of core. The USGS is also playing a key role in the overall effort to preserve data in accessible formats (e.g., widely distributed compact disk data archives), and the AGI is developing a geographic browser for improved access to data on a national basis. The panel recommends continued funding for efforts to preserve, archive, and disseminate data on sedimentary basins. This information was collected through substantial investments by the petroleum industry, and it is unlikely that data gathering on this scale will ever be repeated for sedimentary basins in the United States. If adequately preserved and archived, these data sets will sustain continued advances in basin research for many years. The panel emphasizes that the value of these data will be enhanced by appropriate dissemination (and processing) activities to increase access and provide additional information regarding the content, scope, and quality of the data. There have been efforts to assemble data archives that synthesize the extensive multidisciplinary data sets that have been collected from petroleum-producing regions. Because much of this information is proprietary, these efforts rely on the public release of data. One such archive has been constructed by the Global Basins Research Network for a 60 km × 40 km × 10 km volume of Plio-Pleistocene Gulf Coast sediments. Referred to as a "data cube," the archive synthesizes measurements of surface heat flow; gravity; reflection seismic profiles; well logs; and subsurface temperatures, pressures, and fluid and mineral compositions. The panel believes that these types of comprehensive data archives represent an invaluable source of information for multidisciplinary studies on sedimentary basins and that there should be continued efforts to develop additional data cubes for basins throughout the United States and the world. Role of Scientific Societies Research on sedimentary basins concerns the membership of several scientific societies in the United States, the largest being the Geological Society of America (GSA), the American Association of Petroleum Geologists (AAPG), and the American Geophysical Union. Additional societies that are active in this area include the SEPM
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--> (Society for Sedimentary Geology), the Society of Exploration Geophysicists, the Society of Economic Geologists, the American Institute of Hydrology, the Soil Science Society of America, and the Paleontological Society. On an international scale, there are analogous organizations, such as the International Association of Sedimentologists. Currently, the International Lithosphere Program of the Inter-Union Commission on the Lithosphere coordinates some of these activities through its task force on "The Origin of Sedimentary Basins." This project is focused on strengthening international collaborations between industry and academic scientists in an effort to develop multidisciplinary models of sedimentary basins. Since 1990, the project has sponsored five workshops at scientific meetings in Europe and the Middle East (e.g., Cloetingh et al., 1994). In the effort to develop a comprehensive set of models for sedimentary basins, the panel believes that scientific societies and unions will play an important role. For example, through their meetings and special workshops, societies can shape and focus the research agenda on sedimentary basins. To this end, collaborative efforts between particular societies (e.g., between AAPG and GSA) can facilitate new research strategies. Because societies represent a wide range of scientists from university, government, and industry, they are in an ideal position to coordinate many of the difficult issues in developing collaborative research programs. These include facilitating access to proprietary data, developing industry-academic-government research consortia, developing innovative mechanisms for joint industry-government funding of basin research, and encouraging increased research efforts by the environmental remediation industry. The panel recommends that the broad range of geoscience societies take an active role in facilitating progress toward the development of a comprehensive set of models for sedimentary basins. For this effort, both special sessions at regular meetings and cosponsored symposia or research conferences could be particularly effective. The panel believes it would also be useful for scientific societies to convene joint industry-academic-government roundtable discussions on critical organizational issues for strengthening multidisciplinary research on sedimentary basins. Finally, the panel stresses that it is important for U.S. scientific societies to strengthen their collaborations with ongoing international programs regarding the origin and evolution of sedimentary basins.