HIDROGEOLOGÍA DE UN SECTOR DE LA MARGEN IZQUIERDA DEL RÍO VIRILLA, PROVINCIA DE SAN JOSÉ, COSTA RICA

Abstract

For the first time the hidrogeological features of an area near to the left border of Virilla river, in thecapital of San José, were investigated. The basement of the area is the sedimentary Formación Pacacua, covered by asecuence of flows lava, ignimbrites, tuff layers, mud flows and ashes. The lava flows contain the most importantaquifers of the area signed as Colima Inferior and Colima Superior. The ignimbrite flows form aquitarde and the mudflows low potential acuifer. The direction of the flow of groundwater was defined from East toWest and the rechargearea is situated in the eastern part of San José. In some parts the main rivers of the area are influent and recharge direct-ly water to the upper aquifer.