Assessment of Chaves Low-Temperature CO₂-Rich Geothermal System (N-Portugal) Using an Interdisciplinary Geosciences Approach

Table 3

Representative stable (δ¹⁸O and δ²H) and radioactive (³H) isotopic data of groundwaters from the Chaves region. Table 3 is reproduced from Marques et al. (2006) [under the Creative Commons Attribution License/public domain].

Ref.	Local	Altitude	δ^18O	δ^2H	^3H
ACP1 ()	Vilarelho da Raia	370	−7.71	−53.2
Assureiras ()	Chaves	690	−7.52	−50.7
Castelões ()	Chaves	980	−7.72	−50.1
Campo de futebol ()	Chaves	360	−5.76	−38.5
AC2 ()	Chaves	350	−8.03	−55.9
Nasc. ()	Chaves	350	−7.96	−54.9
Baldio ()	Vidago	510	−6.73	−42.9
N3 ()	Vidago	480	−6.20	−40.8
N6 ()	Vidago	420	−6.42	−41.6
N7 ()	Vidago	580	−6.73	−42.5
AC16 (●)	Vidago	355	−6.63	−48.0
AC18 (●)	Vidago	325	−6.81	−44.5
Areal 3 (●)	Vidago	350	−7.12	−52.2
N1 ()	Pedras Salgadas	660	−6.53	−40.1
N2 ()	Pedras Salgadas	1080	−6.79	−40.0
N5 ()	Pedras Salgadas	885	−7.20	−45.8
AC17 (■)	Pedras Salgadas	580	−7.26	−47.3
AC25 (■)	Pedras Salgadas	560	−7.70	−53.1
AC22 (■)	Pedras Salgadas	570	−8.27	−53.5

Notes: () shallow cold dilute normal groundwaters; () Chaves low-temperature CO₂-rich geothermal waters; cold CO₂-rich mineral waters from () Vilarelho da Raia, (●) Vidago, and (■) Pedras Salgadas. Altitude in m a.s.l.. δ¹⁸O and δ²H in ‰ vs. V-SMOW. ³H in TU.