Náttúrufræðingurinn - 1981, Blaðsíða 52

TAFLA II
Jöfnur fyrir efnahitamæla, kleyfnistuðul kísilsýru og Na + /H + hlutfall i jarðhitavatni
Equations for chemical geothermometers, the dissocialion constant of silicic acid and Na + /H + ratios in
geothermal waters
Kalsedónhiti (Si02 i ppm) — svið 25— 180°C
Chalcedony temperalure (Si02 in ppm) — range 25—180° C
t°C “ 4.69 - 1032 - logH4Si04 273.15 ('a) Fournier (1977)
t°C _ 4.91 - 1112 - logH4SiO., 273.15 (lb)
t°C 1021 273.15 (lc)
4.69 - - logH4SiO.(«l
t°C ~ 5.32 - 1263 - logH4Si04 273.15 (lb’) eftir gufutap1'1
t°C 1172 273.15 (lc’) eftir gufutap1’1
5.10 - - logH4SiO(o;
Kvarshiti (Si02 i ppm) — svið 180—330°C
Quartz lemperature (Si02in ppm) — range 180—330° C
t°C =^——‘;50S* -,t— - 273.15 (2a)Fournier (1977) (180-250°C)
5.19 — logH4SiO.,
t°C
t°C
1164
4.90 - logH ,Si04
1522
5.75 - logH4Si04
273.15 (2b)
273.15 (2a’) Fournier (1977) eftir gufutapb (180—250°C)
Na-K hiti (Na og K í ppm) — svið 25 —250°C
Na-K temperature (Na and K in ppm) — range 25— 250° C
t°C
t°C
t°C
856
logNa/K + 0.857
933______
logNa/K + 0.993
1171
logNa/K + 1.548
273.15 (3a) Truesdell (1975) (100-275°C)
273.15 (3b)
273.15 (3c) lágalbít-míkróklinO
Kleyfnistuðull kísilsýru — svið 0—350°C
The dissociation constant of silicic acid — range 0— 350°C
l°gKH4Si04 = —2549/T°K - 15.36 • 10-6 • T^ °K (4)+
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