| he stable isotope compositions (;Subsurface sediment samples from the barrier bar were granulometrically analyzed to determine putative sedimentological and stratigraphic controls on groundwater movement. Although three distinctive facies were identified within the sand deposits, hydraulic differences among the units were minor and unlikely to affect groundwater flow. A fourth facies, consisting of a poorly-sorted clay-rich till, underlies the sands and functions as an aquitard, confining potential groundwater sources to Lake Erie, Point Pelee marsh, and precipitation.;Water samples of Lake Erie, Point Pelee marsh, local precipitation, tap water and groundwater from two transects (one narrow, one wide) across the barrier sand-bar were collected over a period of four years and analyzed for oxygen- and hydrogen-isotope compositions. The isotopic composition of Lake Erie remained relatively constant (;Precipitation samples collected during a 31 month period were used to determine local meteoric water lines at Point Pelee as well as eight other locations in the Great Lakes region. These lines differed from each other and from the Global Meteoric Water Line (GMWL), but were typical for the region. These data define a previously undescribed relationship in... |
