Representatives from the wide-range of geomagnetic disciplines met at a week-long workshop in Washington, D.C., during March 1992 to address the challenges and opportunities in geomagnetic research and to develop a plan of action to promote future discussion, interaction, and coordination. Crustal magnetic anomalies were an important theme of the workshop, and various recommendations concerning the current state of, and future directions in, the study of crustal magnetic anomalies are expressed in the workshop report, entitled The National Geomagnetic Initiative [ National Resource Council, 1993].
The National Geomagnetic Initiative identified a number of critical needs in order to promote future progress in these areas. Improving the consistency of the digital magnetic anomaly database for the U.S. emerged as a top priority. Consequently, a data task group was formed to develop a rationale and operational plan to upgrade the U.S. magnetic anomaly database. The task group prepared a report that provides an excellent review of the many and varied applications of magnetic anomaly research to problems in waste disposal and groundwater flow, earthquake and volcano hazards, land use and water management, and hydrocarbon and geothermal energy resources. The report, titled Rationale and Operational Plan to Upgrade the U. S. Magnetic Anomaly Data Base, is available from the National Research Council (contact Kevin Crowley, Board of Earth Sciences and Resources, National Research Council, 2001 Wisconsin Ave., NW, Washington, D.C. 20007).
The National Geomagnetic Initiative also found critical needs for the acquisition of higher-resolution data at all scales, from deep-tow marine surveys to satellite missions. A new geomagnetic satellite is needed at sufficiently low-altitudes to focus on lithospheric problems. A mid-depth-tow magnetometer package should be developed to improve resolution of seafloor anomalies and to enhance interpretation of high-resolution swath bathymetric surveys. These and other specialized data will provide for better characterization of the spatial distribution of crustal magnetization leading to improved understanding of important geodynamic processes, such as the evolution of sedimentary basins, continental rift zones, and midocean ridges. Such studies should go hand-in-hand with the development of new ways to analyze, interpret, and visualize magnetic data and with research to understand the fundamental processes of magnetization in oceanic and continental lithologies, especially at depth.
The Office of Polar Programs of the National Science Foundation recently made an aerogeophysical platform available as a research facility for use by the Antarctic earth-science community. This twin-engine plane, geared towards high-resolution surveying, carries a magnetometer, gravimeter, laser altimeter, ice-penetrating radar, and geodetic-quality GPS receivers. This facility demonstrates the increasing importance of aerogeophysical information, including aeromagnetic data, for solving problems in the earth sciences and glaciology.
Acknowledgments. We appreciate the helpful comments and suggestions of the reviewers, Carol Finn and William Hinze. A portion of this report was prepared at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA.