Some may be curious of the U.S. fault lines with earthquakes in the news lately. The fact is most states are at risk of major earthquakes, with 39 of the 50 states in moderate to high risk areas for seismic activity
Atlantic Ocean Floor Map. Groundbreaking map of the ocean floor created by technician Marie Tharp and Professor Bruce Heezen, image via The Earth Institute, Columbia University. Together, Marie and Bruce rewrote 20th century geophysics by creating the first systematic, comprehensive map of the entire ocean floor. This paved the way for general acceptance of the theories of continental drift and plate tectonics.