ABSTRACT
Subsidence associated with the abstraction of fluids has occurred in many parts of the world, for example, according to Zhou et al. (2003) at present it affects over 150 areas. They went on to mention that such subsidence ranges up to 10 m or more and that the areas affected vary in size from several square kilometres to over 10000 km2. In many developing countries where the demand for groundwater is increasing continuously this presents a serious geoenvironmental problem because of the conflict between economic development and environmental protection. Land subsidence due to groundwater lowering represents a very complicated system consisting of various kinds of spatially distributed information such as geology, terrain, land use, precipitation, evapotranspiration, large aquifer systems, hydrological parameter distribution, groundwater abstraction, groundwater flow and groundwater recharge. Frequently, such subsidence has taken time to recognize and to do something about. Consequently, millions of pounds worth of damage may have occurred during the time elapsed. Subsidence most frequently is associated with groundwater withdrawal for supply for domestic, industrial or agricultural purposes but it may be caused by groundwater lowering in relation to mining, quarrying operations, land drainage or in relation to the production of geothermal energy. However, subsidence also is associated with the abstraction of oil, gas and brines.
