NGDC's global ocean sediment thickness grid (Divins, 2003) has been updated for the Australian-Antarctic region (60° -155° E, 30° -70° S). New seismic reflection and refraction data have been used to add detail to the conjugate Australian and Antarctic margins and intervening ocean floor where previously regional sediment thickness patterns were poorly known. On the margins, sediment thickness estimates were computed from velocity-depth functions from sonobuoy/refraction velocity solutions ground-truthed against seismic reflection data.

NCEI's global ocean sediment thickness grid of Divins (2003) updated by Whittaker et al. (2013) has been updated again for the NE Atlantic, Arctic, Southern Ocean, and Mediterranean regions.

The entire collection of GEOSAT ERM (Nov.'86 - Dec. '89) data over land and ice regions is held at the National Geophysical Data Center (NGDC). These data will yield reasonable elevation values for land and ice regions of gently varying elevation. This data collection should not be used in regions of highly variable terrain. This satellite altimeter data base contains precise geoid and gravity anomaly profiles which were constructed from the average of 66 repeat cycles of GEOSAT. The data were developed by Professor David T. Sandwell at the University of California in San Diego.

More than 17 million selected magnetic observations from several orbiting low-altitude satellites are contained in this digital collection. Except for MAGSAT, all the observations are of total intensity (F) only. The MAGSAT data contain both scalar and vector X, Y, Z) values. MAGSAT was launched into a sun-lit, sun- synchronous orbit (350 to 550 km high) on October 30, 1979 with re- entry occurring on June 11, 1980. The MAGSAT data are being used for derivation of magnetic field models, magnetic field mapping, magnetic anomaly mapping, and inner earth studies.

Several regions are represented in this unique collection of earth surface measurements of magnetic field parameters and their related anomalies. The DNAG Magnetics "Super grid" of Magnetic Anomaly Map of North America was created from the four "Original" DNAG Magnetic data sets distributed by The Committee for the Magnetic Anomaly Map of North America, 1987. This development of a super grid involved an extensive task of matching original quadrant information and eliminating overlap.

Information on the past and present orientation of the Earth's magnetic field is available from the National Geophysical Data Center (NGDC) which serves as the national data bank for geomagnetic data. The Earth's magnetic field has been measured by land surveys, ships, aircraft and satellites at hundreds of locations resulting in millions of observations. Many of the observations are of poor quality or are unevenly distributed around the globe.

The Crustal Ages of the Ocean Floor Poster was created at NGDC using the Crustal Ages of the Ocean Floor database draped digitally over a relief of the ocean floor database. The Crustal Ages of the Ocean Floor database was created by a consortia of marine scientists including Dr. R. Dietmar Muller, Dept. of Geology and Geophysics, University of Sydney, Australia, Dr. Walter R. Roest, Geological Survey of Canada, Ottawa, Canada, Dr. Jean-Yves Royer, Lab. de Geodynamique, Villefranche Sur Mer, France, Dr. Lisa M. Gahagan, Institute for Geophysics, University of Texas, Austin, Texas, and Dr.

Project Magnet data include low altitude, high density individual track line surveys, high altitude vector data and regional magnetic anomaly grids.

In 1974, the Ministry of Geology of the U.S.S.R. published a mosaic series of 18 sheets at 1:2.5 million scale showing the residual magnetic intensity over the land mass of the U.S.S.R

As part of a two-year assessment of the geology and mineral resources of the Altiplano and Cordillera Occidental, Bolivia, aeromagnetic and gravity data were acquired from various sources and merged into digital data sets. The data were published as contour mapes (Plates 4 and 5 of Cady and Wise, 1992, USGS) in the final report of the study, USGS Bulletin 1975. The Bolivian Ministry of Mines and Metallurgy recently approved these data for release to the public.