HYDROGEOPHYSICAL APPLICATIONS IN COASTAL AQUIFERS

In many countries all around the world, the most densely populated regions are located in coastal areas since they normally provide the best conditions for both economical development and quality of life. On the other hand, coastal zones more than other regions suffer from natural disasters such as flooding and tsunami as well as from scarcity of fresh groundwater due to seawater intrusion. The latter problem is usually caused by a violation of a delicate hydrogeological balance that exists between freshwater and seawater in coastal aquifers. In most cases, the balance is disturbed by groundwater pumping and other human activities (e.g. land drainage) that lower groundwater levels and ultimately cause seawater encroachment into coastal aquifers. Although this problem is fairly important in all coastal aquifers, it becomes crucial in arid and semi-arid regions, where precipitation is limited and groundwater thus represents the main, if not only, source of fresh water.