Evaluating groundwater recharge processes using stable isotope signatures—the Nabogo catchment of the White Volta, Ghana

Identifying Groundwater Recharge Sites through Environmental Stable Isotopes in an Alluvial Aquifer

“…Rainwater samples in the study area present suggested d-excess values in the range of −11.81‰ and 35.80‰, with an average of 19.88‰. Of all the samples, 82.75% presented d-excess values higher than 10, which suggests the probable inputs of recycling water vapor and the contribution of possible surface flows to the rain clouds according to Fynn [29], where it was also established that low d-excess values may also have been derived from isolated local moist air masses having those characteristics. The d-excess value is a function of several factors, such as the temperature, humidity, and the isotopic characteristics of the ambient water vapor and the evaporating water.…”

“…The average value of 32.76‰ was different from that of the local meteoric water line, making the evolutionary trend from precipitation in the study area to groundwater unclear. A higher variability of groundwater data was found, according to the research presented by Fynn et al [29], and this variability suggests inputs from various sources and the spatial variability in the nature of the vadose zone. Variable infiltration rates are imposed by the spatial heterogeneity of the material of the vadose zone, leading to variable exposures of the infiltrated water to the effects of fractionation attending evaporation.…”

Assessment on connection between shallow and deep aquifers using isotope analysis of surface water and groundwater in Sunsari and Morang Districts

“…The slope greater than 8 in all samples implies less or no evaporation effect (Clark and Firtz, 1997) and intercept (dexcess) value greater than 10‰ in most of the samples suggests that the probable input to the recharge is recycling water vapor contributed by the possible surface flows (Fynn, 2016). The wide variation in isotopic signature (ä18O: -10.16‰ to -4.74‰) might be the reflection of multiple recharge source (Keesari et al, 2017).…”

Source, Age, and Evolution of Coal Measures Water in Central-South Qinshui Basin, China

“…According to the investigation of chemical reactions controlling the chemistry of groundwater in an isthmus lying between Crystal Lake and Big Muskellunge Lake, Northern Wisconsin, Kim revealed that other reactions or processes such as cation exchange can also regulate groundwater chemistry characteristics besides mineral dissolution. Fynn et al evaluated the source and evolution of groundwater in parts of the Nabogo catchment of the White Volta Basin in Ghana and suggested an evolutionary model and the mode of fluid fluxes. Huang et al studied the sources of groundwater recharge in an arid area in Northwest China, aiding in water resource management and groundwater inrush prevention in the coalfield and at other coal mines.…”

“…Previous research works mainly identified the source, origin, and evolution laws by ion characteristics, stable isotopic features, and hydrogen radioisotope dating, − ,− but these cannot accurately ascertain the origin and age of coal measures water because the half-life of hydrogen radioisotopes is quite short (only 12.43 a). In this study, by combining water types, salinities, and ions with stable isotope characteristics of coal measures water and simultaneously introducing a long half-life radioisotope, 129 I (dating range from 0 to 80 Ma), and a short half-life radioisotope, 14 C (dating range from 0 to 5 × 10 4 a), the source, age, and evolution of coal measures water in the study area were investigated more precisely.…”