EVALUACIóN HIDROGEOLóGICA PRELIMINAR DE LAS UNIDADES GEOLóGICAS DE LA MESA DE LOS SANTOS, SANTANDER

this paper present a preliminary hidrogeological evaluation of la mesa de los santos' lithostratigraphic formations, based on the geological mapping, stratigraphy and inventory of water points. all this is supplemented with the analysis of primary porosity by means of the petrographic study and the secondary porosity related statistically with the quantity of fractures of each formation, as well as opening, interconnection and dip. it is made an approach to hydrogeological potential of the geologic outcropping formations in la mesa de los santos, department of santander, from the stratigraphic and petrographic analysis and the structural features of these formations. the upper member of los santos formation presents the highest potential because of rock's fracturing, continued by the lower member with low primary porosity and half fracturing. silgará formation, granito de pescadero, jordán formation and some sections of the sandy levels of the rosablanca formation presents a lowest potential due to its low porosity and low grade of fracturing. low permeability is presented in the middle member of the los santos formation, paja and tablazo formations, as well as in sectors of the forementioned formations and in the quaternary deposits.