@article{fdi:010073230,
  title = {{E}vidence of a water delta {O}-18 negative shift driven by intensive deep {CO}2 upflow at {S}hiwaga gas field ({R}ungwe, {T}anzania)},
  author = {{B}ergonzini, {L}. and {D}elalande-{L}e {M}ouellic, {M}. and {G}herardi, {F}. and {M}athe, {P}. {E}. and {M}ajule, {A}. and {W}illiamson, {D}avid},
  editor = {},
  language = {{ENG}},
  abstract = {{L}ocated on the flank of {N}gozi volcanoes ({T}anzania), the {S}hiwaga gas field is a spot of intense {CO}2(g) emanations. {P}hysico-chemical measurements on different types of waters (rivers, puddles, and springs) as water and gas sampling were discontinuously performed over 10 years for equilibrated partial {CO}2 pressure calculations and stable isotopic analyses. {T}he most striking result shows that meteoric {H}2{O} and deep originated {CO}2(g) exchanges are responsible for a negative {O}-18-shift of the studied waters in relation with waters electrical conductivity, p{H}, and p{CO}(2)eq changes. {I}n spring waters, a maximum shift of - 11.2a{E}uro degrees in delta {O}-18 was observed and p{CO}(2)eq values up to 1196 mbar were computed. {A}lthough this trend has already been reported around the world, such extended shift is rarely measured and requires an important amount of {CO}2(g), with a {CO}2(g)/{H}2{O} ratio up more than 0.5 mol/mol. {T}his approach is useful to better understand the hydro-geochemical processes involved in such environments. {M}oreover, this study evidences that an inventory as a monitoring of these gas fields are needed for the management of natural hazards and local resources.},
  keywords = {{G}as field ; {S}table isotope hydrology ; {CO}2-{H}2{O} interaction ; {W}ater {O}-18 ; shift ; {E}ast {A}frican {R}ift ; {TANZANIE} ; {SHIWAGA} {VALLEE}},
  booktitle = {},
  journal = {{E}nvironmental {E}arth {S}ciences},
  volume = {77},
  numero = {13},
  pages = {art. 497 [9 p.]},
  ISSN = {1866-6280},
  year = {2018},
  DOI = {10.1007/s12665-018-7665-2},
  URL = {https://www.documentation.ird.fr/hor/fdi:010073230},
}