ABSTRACT
Man-induced changes of subsurface materials and processes are highly diverse and cover a broad spectrum of earth science. Depending on the circumstances, these changes may be small or great, slow or fast, and involve disruptions that displace materials, down, up, or laterally. With minor exceptions, have scientists and engineers started to address problems associated with subsurface influences. Although man lives on the earth's surface, nearly all his activities interact in some manner with the subsurface realm. Loading effects are discussed by reference to the consequences of dams and reservoirs, of water injection, of irrigation, and of buildings and other man-made structures. Water injection schemes are those associated with pumping into aquifers to reverse salt water intrusion in coastal areas, and into petroleum reservoir strata to enhance oil recovery. Earthquakes have also resulted from water injection into the Snipe Lake oil field of Canada and from hydraulic salt mining operation at Dale, New York.
