Resumen
Environmental isotope tracers have been a useful tool in providing new insights into hydrologic processes. In Mexico, there have been several studies reporting different values for d18O and d2H for certain geographical areas. The objective of this study is to achieve the isotopic characterization of rainfall and groundwater and to report the comprehensive understanding of groundwater flow processes around and within the Calera aquifer and, consequently, its potential recharge sites. The samples used for the stable isotope analysis ( d18O,d2H ) were measured using a GV-Isoprime isotope-ratio mass spectrometer at the Isotopy Laboratory of the Water Center for Latin America and the Caribbean. The dD of precipitation ranged between -110.20? and 10.11?, with a mean of -55.67? ± 27.81?. The d18O ranged between -17.80? and 2.74?, with a mean of -9.44? ± 4.74?. The dD of groundwater ranged between -81.92? and -36.45?, with a mean of -66.05? ± 8.58?. The d18O ranged between -18.26? and -8.84?, with a mean of -12.35? ± 2.12?. The local meteoric water line of the Zacatecas state is dD=-2.03+5.68d18O . The groundwater samples were clustered into four groups. The clustering of the samples led to the finding that streamflows play a significant role in the hydrological balance as a source of local recharge to the aquifer.