Environmental isotopes and their application on the groundwater aquifers of Wadi Watir basin, South Sinai, Egypt

Wadi Watir basin (3440 km2) is one of the main hydrographic basins of Gulf of Aqaba drainage system. It is bounded by longitudes 34 deg. 00 min. and 34 deg. 30 min. E and latitudes 29 deg. 20 min. and 29 deg. 20 min. N. Its main channel runs in N-S for about 40 km and then bends slightly NNW-SSE direction for about 25 km, where it debouches its load in the Gulf of Aqaba. The surface of Wadi Watir is covered by sedimentary Paleozoic and Cretaceous rocks particularly in its middle and upper parts while in its down part, it is occupied by highly fractured basement rocks (granites and granodiorite) traversed by some dykes. The alluvial deposits form a delta at its connection with the Gulf of Aqaba. The purpose of this study is to use the environmental isotopes to assess the recharge sources of the aquifers in both Wadi Watir main channel and its delta. Twenty three water samples were collected from piezometers, dug wells and drilled wells, as well as two springs in addition to one sample from Gulf of Aqaba