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Table 10 Summary of statistical results obtained from the geochemometric evaluation study of gas geothermometers

From: GaS_GeoT: A computer program for an effective use of newly improved gas geothermometers in predicting reliable geothermal reservoir temperatures

Evaluation metrics Geothermal reservoir-typea Gas Geothermometers (new and existingb); NWGDB nw = 265 data (LIQDR: g1 = 178; VAPDR: g2 = 87)
Percent difference   GasG1 GasG2 GasG3 GasG4 GasG5 GasG6 GasG7 GasG8 ND84c AG85b AG85d AG85f
Number of Samples (%—applicability)
Over-estimation (DIFF% ≤ 20%) LIQDR 103(60) 111(63) 99(58) 105(63) 93(55) 101(58) 97(58) 101(58) 70(39) 57(32) 55(31) 67(38)
VAPDR 38(44) 42(52) 43(50) 37(48) 47(54) 51(59) 48(57) 42(48) 27(31) 62(71) 67(77) 69(79)
Under-estimation (DIFF% ≤ 20%) LIQDR 56(32) 56(32) 52(30) 50(30) 57(34) 54(31) 53(31) 56(32) 94(53) 104(58) 117(66) 88(49)
VAPDR 43(49) 32(39) 38(44) 36(47) 34(39) 29(34) 30(35) 39(45) 53(61) 20(23) 16(18) 13(15)
Equal to BHT (DIFF% ≤ 1%) LIQDR 14(8) 8(5) 20(12) 11(7) 19(11) 19(11) 19(11) 18(10) 14(8) 17(10) 6(3) 23(13)
VAPDR 6(7) 7(9) 5(6) 4(5) 6(7) 6(7) 7(8) 6(7) 7(8) 5(6) 4(5) 5(6)
Rankingc   1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th
DIFF% (± 20%)d LIQDR GasG8 GasG3 GasG1 GasG7 GasG4 GasG2 GasG5 GasG6 AG85d AG85b ND84c AG85f
168(96) 164(96) 164(95) 160(95) 157(95) 163(93) 156(92) 159(91) 156(88) 154(87) 152(85) 152(85)
VAPDR A98c GasG3 GasG5 GasG1 ND84c GasG2 GasG4 GasG8 ND84b GasG6 AG85f GasG7
74(85) 73(85) 73(84) 71(82) 71(82) 66(82) 62(81) 70(81) 70(81) 69(80) 69(79) 66(78)
RMSE (°C) LIQDR GasG3 GasG8 GasG5 GasG6 GasG7 GasG1 GasG2 GasG4 AG85b AG85d AG85f ND84c
31.6 31.8 32.6 33.2 33.4 33.5 33.9 34.7 36.9 38.7 38.8 45.2
VAPDR GasG3 GasG1 ND84c A98c GasG2 ND84b AG85f GasG6 GasG8 GasG7 GasG5 GasG4
35.6 38.0 38.9 39.8 39.8 40.1 41.0 41.9 42.1 43.4 44.8 49.0
MAE (°C) LIQDR GasG8 GasG5 GasG3 GasG7 GasG4 GasG1 GasG6 GasG2 AG85f AG85b AG85d ND84c
25.2 25.2 25.3 25.8 26.3 26.5 26.6 27.3 27.7 28.3 30.6 33.9
VAPDR GasG3 GasG1 GasG2 GasG6 GasG5 A98c GasG8 ND84c ND84b GasG7 AG85f GasG4
27.6 29.3 30.2 30.4 31.3 31 32.1 32.7 33.8 33.8 34.0 39.2
MAPE (%) LIQDR GasG5 GasG3 GasG8 GasG7 GasG4 GasG1 GasG6 GasG2 AG85b AG85f AG85d ND84c
9.1 9.1 9.1 9.3 9.4 9.5 9.6 9.8 10.0 10.6 11.3 12.6
VAPDR GasG3 GasG1 GasG2 GasG6 GasG5 A98c GasG8 ND84c GasG7 AG85g ND84b GasG4
10.6 11.2 11.5 11.8 11.9 11.9 12.4 12.7 12.8 12.9 13.1 15.4
Theil's U test LIQDR GasG3 GasG8 GasG5 GasG7 GasG6 GasG1 GasG4 GasG2 AG85b AG85d AG85f ND84c
VAPDR GasG3 GasG1 ND84c A98c ND84b AG85f GasG2 GasG6 GasG8 GasG7 GasG5 GasG4
  1. aType of geothermal reservoir used to calibrate the gas geothermometers
  2. bFor the existing gas geothermometers (literature), we have selected only the best four geothermometers
  3. cThe full ranking can be checked in the Additional file 1: Tables S8 to S13
  4. dWithin the limits of acceptance. The new gas geothermometers were typed in italic font