Radiokrypton unveils dual moisture sources of a deep desert aquifer.

ABSTRACT: In arid regions, groundwater is a vital resource that can also provide a long-term record of the regional water cycle. However, the use of groundwater as a paleoclimate proxy has been limited by the complex hydrology and the lack of appropriate chronometers to determine the recharge time without complication. Applying ⁸¹Kr, a long-lived radioisotope tracer, we investigate the paleohydroclimate and subsurface water storage properties of the Nubian Sandstone Aquifer in the Negev Desert, Israel. Based on the spatial distributions of stable isotopes and the abundance of ⁸¹Kr, we resolve subsurface mixing and identify two distinct moisture sources of the recharge: one recent (<38 ky ago) from the Mediterranean and the other 361 ± 30 ky ago from the tropical Atlantic, both

SUBMITTER: Yokochi R 

PROVIDER: S-EPMC6697870 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature