By LaMoreaux, Philip E.; LaMoreaux, James W.
(Editor's note: we have preserved the scholarly format of this wonderful resource so that its references will be fully available to the eager teacher and student).
Introduction: an ancient understanding of caves
Man was intrigued with karst, particularly cave development, long before the word "karst" came into use. In pre-historic times caves provided humans with a living space, water supply, and protection. In the cave area of southern France, in the Pyrenees and in northern Spain that were outside the influence of the massive Continental Pleistocene Glaciers, the Paleolithic Period of man's evolution was a scene of remarkable cave drawings illustrating an amazing capability of early man to duplicate pictures of animals and hunting activities. He had chosen these caves as living areas, and his exploratory drive led him deep underground to sources of water. These were man's first attempts to explore and understand karst and use these natural phenomena to enhance his living conditions and safety. During Greek times, caves, underground rivers, and springs were a part of Greek mythology, and the subject of much discussion by Greek and Roman philosophers. The earliest hydrologic concepts of the hydrologic cycle, water source, occurrence, and quality were related to a karst setting.
How important is karst to man's environment? In Yugoslavia, the home of the term "karst", 33 percent of the surface is karst terrain (Milanovic, 1981). In the USSR, 40 percent of the land area consists of carbonate and other soluble rocks, and in the United States about 25 percent is underlain by carbonate rocks. Approximately one-fifth of the earth's surface is underlain by carbonate rocks of a complex physical character that produced a diverse topographic expression by weathering under varied climatic conditions. Carbonate terranes in some areas are underlain by broad, rolling plains, whereas in others they are characterized by steep bluffs, canyons, sinks, and valleys. Owing to the variability of the solubility of limestone under different climatic and geologic conditions, man's inhabitation and development of limestone areas has often been difficult. In some areas the limestone is covered by fertile soils; in others soils are missing. In the Midwest of the USA, a large area underlain by limestone is covered by a very productive, rich soil that produces large quantities of food. This area is literally "the breadbasket of a nation."
Carbonate rocks are a source of abundant water supplies, minerals, and oil and gas. Even though there are many blessings associated with carbonate terranes, there are also many problems related to developing an adequate water supply, assuring proper drainage, providing stable foundation conditions, and preventing serious pollution problems. Because of this complexity, the evolution of concepts related to the movement and occurrence of ground water in karst, methods of exploration and development of water, safe engineering practices in construction of all kinds, and adequate environmental safety precautions cannot be based on one uniform set of rules.
The impact of karst terranes is great on man and of substantial interest financially. This is recognized by a few select references from publications: John Newton (1986), "Development of Sinkholes Resulting from Man's Activities in the Eastern United States," reports that in the 19 states included in the study, since 1950 there have been more than 6,500 sinkholes or related features that have occurred. Newton further states that the total cost of damage and associated protective measures resulting from these induced sinkholes is unknown, however, at five dam sites alone repair costs were in excess of $140 million. In a report presented by Dallas Peck, Director of the U.S. Geological Survey, in October 1988, in a paper, "Karst Hydrogeology in the United States of America," at an International Karst meeting in Guilin China, he makes the statement, "karst aquifers are a major source of drinking water in the USA that provided 25 million cubic meters of water per day in 1985. …