Decade of North American Geology Geologic Map of North America—Perspectives and explanation

“The new Geologic Map of North America covers ~15% of Earth’s surface and differs from previous maps in several important respects: It is the first such map to depict the geology of the seafloor, the first compiled since the general acceptance of plate-tectonic theory, and the first since radiometric dates for plutonic and volcanic rocks became widely available. It also reflects enormous advances in conventional geologic mapping, advances that have led to a significant increase in the complexity of the map. The new map, printed in 11 colors, distinguishes more than 900 rock units, 110 of which are offshore. It depicts more than seven times the number of on-land units as are shown on its immediate predecessor, as well as many more faults and additional features such as volcanoes, calderas, impact structures, small bodies of unusual igneous rocks, and diapirs. When displayed at earth science institutions and libraries, this map is sure to impress viewers with the grand design of the continent and may inspire some to pursue the science of geology. The new Geologic Map of North America is also a “thinking map,” a source for new interpretations of the geology of North America, insights into the evolution of the continent, new exploration strategies for the discovery of mineral and energy resources, and the development of better ways to assess and mitigate environmental risks and geologic hazards.3 sheets (North, South, and Legend), approximately 74 x 40 inches.”