The University of Chicago Magazine December 1995
Missing Mountains. Were the Appalachians the Himalayas of long ago? These views-looking northeast across the inset region of North America-show the mountains when pushed up by a collision with Africa (top map; Africa is not drawn), and today, after 260 million years of erosion. The maps present a geologic riddle: How to measure the amount of missing rock? Graduate student Michael Hulver looked to deeper material like coal and conodont fossils. Taller mountains weigh more, heating these materials, whose transformations yield an indirect measure of height. As the maps reveal (average, not peak, elevations are used), the Appalachians never reached Himalayan heights of 3 to 5 kilometers. Yet they still shaped the ancient climate, models of which will gain from Hulver's reconstructed topography.
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