Karst hydrogeology in the United States

Abstract

Karst hydrogeology has been the subject of much study in the United States. About 15 percent of the conterminous United States has carbonates, gypsum, or other soluble rocks at the land surface. Dissolution of these rocks has formed karst topography at the surface and karst features in aquifers that are a major source of drinking water. Carbonate aquifers, however, are commonly vulnerable to contamination from the land surface. In 1985, about 25 million cubic meters of water per day was withdrawn from carbonate aquifers in the United States. Three fields of current karst research in the United States are water-resources management, sinkhole formation, and carbonate geochemistry and geomorphic consequences. Examples of karst fields where these areas of research are continuing, include Alabama, Florida, and Puerto Rico.

Puerto Rican Karst-A Vital Resource

“…In fact, karst features can develop at any time even if the limestone is buried, because of the possibility of subterranean solution on lands where the presence of limestone is not apparent. Some 50 million km 2 of land on Earth-20 percent of its surface-is considered karstifiable, and about 15 percent of the contiguous United States have temperate karst (Peck et al 1988). In Puerto Rico, the limestone region covers 244,258 ha or 28 percent of the island (table 2).…”

“…Uses of the region would include freshwater production and protection, wilderness, restoration of wildlife populations, conservation of biodiversity, passive recreation, ecological tourism, forest products and services, education, and research. Research in the karst region has relevance to its own conservation and also to the karst problems in the United States (Peck et al 1988) and the rest of the world (White 1988).…”