A NORTH AMERICAN PALEOGEOGRAPHY SITE

Ron Blakey, a geologist at Northern Arizona University, has put together a very useful site, tracking the geography of North America over the last 550 million years. The site features 40 maps which were prepared with the core of North America (Laurentia) fixed. All other tectonic elements are shown moving against or splitting away from Laurentia, thus showing clearly accretionary and rifting events in North America's geologic history. The views were prepared by wrapping a rectangular outline map on a sphere and viewing the globe rotated to 35° N and 100° W. Various stratigraphic, tectonic, and sedimentologic data were added to the map. Topography was "cloned" from digital elevation maps of modern Earth from the USGS, NOAA, and other sources. Colors were adjusted to portray climate and vegetation for the given time and location. The geologic data were gathered from the references listed at the web
site.
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MIDDLE MISSISSIPPIAN PALEOGEOGRAPHY OF NORTH AMERICA image by Ron Blakey