10 Km/pixel Geologic Maps: Notes and References

Steven Dutch, Professor Emeritus, Natural and Applied Sciences, Universityof Wisconsin - Green Bay

Scale: 1 pixel = 10 km. 10-degree grid. Maps centered on the equator are Mercator projection with true scale along the equator. Maps centered at other latitudes are Lambert Conformal Conic projection. Standard parallels for those maps are 5 degrees north and south of the map center. Polar maps are Lambert Azimuthal Equal Area. Maps of North America, South America and Africa-Europe are Transverse Mercator.


Ocean floor ages in the open oceans are mostly interpreted from magnetic anomaly data and validated by sea floor sampling and drilling. Ages in smaller closed basins like the Gulf of Mexico, Caribbean and Mediterranean appear to have been based on plate-tectonic reconstructions.

The Black Sea and southernmost Caspian Sea are widely believed to be floored by trapped oceanic crust of unknown age, probably early Mesozoic or late Paleozoic. On these maps they have been assigned the color for 230-240 my.


Ocean floor age data are from Mueller, R.D., M. Sdrolias, C. Gaina, and W.R. Roest 2008. Age, spreading rates and spreading symmetry of the world's ocean crust, Geochem. Geophys. Geosyst., 9, Q04006, doi:10.1029/2007GC001743. (http://www.ngdc.noaa.gov/mgg/ocean_age/data/2008/grids/age/) Data were contoured at 10 Ma intervals using Global Mapper 14.0. Some artifacts created by the original data gridding process were removed manually.

Coastlines and major lakes were simplified from the CIA World Data Bank II. Rivers and boundaries are also from the CIA World Data Bank II, supplemented by recent boundary changes.

Topography and bathymetry were based on the ETOPO1 data set: Amante, C. and B. W. Eakins, ETOPO1 1 Arc-Minute Global Relief Model: Procedures, Data Sources and Analysis. NOAA Technical Memorandum NESDIS NGDC-24, 19 pp, March 2009. (http://www.ngdc.noaa.gov/mgg/global/global.html), displayed using Global Mapper 14.0.

Fracture zone and magnetic anomaly data are based on The Global Seafloor Fabric and Magnetic Lineation Data Base Project, http://www.soest.hawaii.edu/pT/gSFML/; Published Magnetic Picks for Tectonic Reconstruction, http://www.soest.hawaii.edu/pT/gSFML/mL/index.htm and Matthews, K. J., R. D. Mueller, P. Wessel, and J. M. Whittaker (2011), The tectonic fabric of the ocean basins, J. Geophys. Res., 116(B12109); http://www.soest.hawaii.edu/pT/gSFML/SF/index.htm.

Land Geology: Chorlton, L. B. (Compiler), 2007: Generalized Geology of the World: Bedrock Domains and Major Faults in GIS Format; Geological Survey of Canada, Open File 5529, 1 CD-ROM. © Her Majesty the Queen in Right of Canada 2007. Accessible on-line from Natural Resources Canada.

The land geology is highly generalized and certain familiar features are presented in unfamiliar ways.

Return to Global Geology Index.htm
Return to Professor Dutch's Home Page

Created 11 April 2014, Last Update 19 January 2020