Chemical Geothermometers and Their Application to Formation Waters from Sedimentary Basins

The isotopic and chemical composition of CO2-rich thermal waters in the Mont-Dore region (Massif-Central, France)

“…They can be applied to those fluids that are the most representative of deep fluids with respect to the other cations. The Na/Li geothermometers (Fouillac and Michard, 1981;Kharaka and Mariner, 1989) give temperatures higher than those estimated using other geothermometers. Lithium is usually present as a trace element in minerals, and relationships between the Na/Li ratio and temperature can vary with the nature of the Libearing secondary minerals.…”

“…The Mg/Li geothermometer (Kharaka and Mariner, 1989) was developed for formation waters with much higher salinities than the present ones. It can also be used for low-temperature reservoirs, because of the relatively rapid exchange of Li and Mg with clay Kharaka and Mariner (1989); (6) Mg/K' equation of Giggenbach (1988); (7) '*O isotope geothermometer of Mizutani and Rafter (1969b) SiOs ( 151 152 143 152 152 152 151 148 115 109 113 94 127 112 120 111 138 98 126 173 174 166 174 174 174 173 171 142 136 139 122 151 139 145 247 242 194 233 238 231 ...…”

“…It can also be used for low-temperature reservoirs, because of the relatively rapid exchange of Li and Mg with clay Kharaka and Mariner (1989); (6) Mg/K' equation of Giggenbach (1988); (7) '*O isotope geothermometer of Mizutani and Rafter (1969b) SiOs ( 151 152 143 152 152 152 151 148 115 109 113 94 127 112 120 111 138 98 126 173 174 166 174 174 174 173 171 142 136 139 122 151 139 145 247 242 194 233 238 231 215 240 124 209 188 198 127 136 134 132 105 251 246 201 237 242 236 220 244 135 151 216 112 195 119 205 85 137 126 146 119 144 119 142 158 116 139 88 87 89 87 87 88 83 86 92 91 83 92 90 91 90 86 91 125 132 114 176 110 172 80 98 154 96 98 1...…”

“…Temperatures of fluids emerging at Saint-Nectaire calculated with chemical and isotope geothennometers (1) Quartz geothermometers, (2) Na/K equation of Truesdell (1976); (3) Na/K equation of ; (4) Mg/Li equation of Kharaka and Mariner (1989); (5) Mg/Kz equation of Giggenbach (1988); (6) "0 isotope of Mizutani and Rafter (i969b). minerals (Kharaka and Mariner, 1989), and plausible results have been obtained for it (Land and Macpherson, 1992;Pauwels et al, 1993). When applied to the Moneyron, Choussy and Croizat fluids (Table 6), this geothermometer indicates temperatures between 130 and 16O"C, which are slightly higher than those estimated using Na/K and Mg/K' geothermometers.…”

Lithium isotopes in island arc geothermal systems: Guadeloupe, Martinique (French West Indies) and experimental approach

“…However, the values estimated for such temperatures are not always consistent with each other. The three Na/Li thermometric relationships (Fouillac and Michard, 1981;Kharaka et al, 1982;Kharaka and Mariner, 1989), differ from classical geothermometers in that they associate a major (sodium) and a trace element (lithium), the latter of which giving an additional temperature constraint.…”