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Isotopic and hydrochemical tracing for a Cambrian-Ordovician carbonate aquifer system of the semi-arid Datong area, China
Published in A. Kranjc, Tracer Hydrology 97, 2020
Gu Wei-Zu, Gui-Jim Ye, Lin Zeng-Ping, Chang Guang-Ye, Fu Rong-An, Fei Guang-Chan, Jing Zhi-Mno, Zheng Ping-Sheng
Oxygen and hydrogen isotopes in groundwater of this SMЄO aquifer system with 61 data sets of 1994 - 1995 from 22 boreholes vary in a way that is distinguishable from that of meteoric water (Fig.2). The observed δ 18O values range from -8.12 ‰ to -12.56 ‰. For all data sets it fits δ2D=6.173δ18O−10.656
Palaeoproterozoic magnesite from playa/sabkha environments
Published in Adam Piestrzyński, Mineral Deposits at the Beginning of the 21st Century, 2001
V.A. Melezhik, A.E. Fallick, P.V. Medvedev, V.V. Makarikhin
δ13C and δ18O values range from +9.0 to +11.6‰ (mean +10.1 ± 1.0‰), and from 20.0 to 25.7‰ (mean 22.2 ± 1.7‰), respectively. Overall the magnesites and their host dolostones are rather similar in carbon isotope ratios. One magnesite bed is characterised by slightly elevated δ18O values (25.0‰ on average), compared to the average host dolostone (21.3‰) and intergrown dolomite (21.6‰).
Dominant factors influencing changes in the water quantity and quality in the Dianshi Reservoir, East China
Published in Human and Ecological Risk Assessment: An International Journal, 2022
Fengmei Su, Peiyue Li, Misbah Fida
In addition, stable isotopes, δ2H and δ18O, were used to determine whether the precipitation is the main recharge source for the Dianshi Reservoir. Indeed, the isotopes δ2H and δ18O represent the variation degree of the hydrogen and oxygen isotopic compositions of the sample as compared to that of the standard VSMOW (Vienna Standard Mean Ocean Water) (Zhang et al. 2020). The δ2H and δ18O can be calculated according to the following formulas:where RHsample and RHstandard denote the value of 2H/H in the drinking water sample and VSMOW, respectively; ROsample and ROstandard denote the value of 18O/16O in the drinking water sample and the VSMOW, respectively.
Shift from nival to pluvial recharge of an aquifer-fed lake increases water temperature
Published in Inland Waters, 2019
Giovanna Flaim, Ami Nishri, Federica Camin, Stefano Corradini, Ulrike Obertegger
Water samples for isotope analysis were held in sealed bottles and kept refrigerated until analysis, usually within 24 h. The 18O/16O ratio of water was determined after equilibration of water with CO2 with a known content of 18O (C16O2 + H218O = C16O18O + H216O) using an isotope ratio mass spectrometer (Isoprime, Manchester, UK) interfaced with an online automatic system that allows CO2/H2O equilibration (Multiflow, Isoprime, Manchester, UK). The 18O/16O ratio was expressed as delta per thousand (δ18O‰) as the deviation of the isotope ratio of the sample from the international reference standard (i.e., Vienna Standard Mean Ocean Water, International Atomic Energy Agency [IAEA], Vienna, Austria) on a scale normalized by assigning the consensus value of −55.5‰ to Standard Light Antarctic Precipitation (SLAP; water, IAEA). Analytical uncertainty (1 SD) of δ18O values was <0.2‰.
Assessing moisture sources of precipitation in the Western Pamir Mountains (Tajikistan, Central Asia) using deuterium excess
Published in Tellus B: Chemical and Physical Meteorology, 2019
Tobias R. Juhlke, Christiane Meier, Robert van Geldern, Kim A. Vanselow, Jakob Wernicke, Jamila Baidulloeva, Johannes A.C. Barth, Stephan M. Weise
The results of monthly integrated samples for oxygen and hydrogen stable isotopes are shown in a dual isotope plot of δ2H against δ18O (Fig. 3). Values for δ18O range between –24.4‰ and –2.0‰, whereby minimum values are reached in the cold season (boreal winter), while maximum values were observed during warm season (boreal summer). The Local Meteoric Water Line (LMWL) calculated from the samples (Fig. 3) has the equation which is quite similar to the GMWL (Eq. 1). As outlined in the introduction, several effects occurring during transport of atmospheric moisture and rainout have an impact on the isotopic composition of any precipitation sample. Therefore, we limit the subsequent detailed discussion to the deuterium excess parameter, which should be less affected by these processes and thus a better indicator for moisture transport.