Marble Tombstone Weathering and Air Pollution in North America


FAX 302/831–8273, e-mail


Abstract Maps of surface recession rates measured from 8,438 century-old Vermont marble tombstones at 320 cemeteries throughout North America and Hawaii demonstrate that air pollution (probably SO2) has been responsible for more deterioration of carbonate building stone and statuary than have other weathering processes. Upper stone faces in heavily polluted localities (mean SO2 concentrations of 350 ug/m3) have receded at a mean rate >3 mm/100 yrs due to granular disintegration induced by growth of gypsum crystals between the calcite grains. Stone degradation rates are negligible in dry areas (western U.S., Great Plains); rainy, less polluted locales (Hawaii, southeastern U.S.); cold regions (Canada, high-altitude Rocky Mountains); and near tall-stack, coal-fired power plants. Weathering rates have been rapid where charcoal or high-sulfur coals have been used as fuel (industrial cities of the eastern US., small towns in the mid-west, ore smelters). Weathering rates strongly correlate with modeled SO2 inputs for 18 American cities over a century, allowing for the development of a long-term marble dose-response function.