Table 3 Thresholds, and anomalies of the detected hydrothermal alterations (and their intersections), using band ratios of the four utilized datasets.
BR | Mean | Standard deviation | Threshold | Anomalies (km2) | Overestimated area |
|---|---|---|---|---|---|
ASTER 4/7 | 116.73 | 62.20 | 178.93 | 252.1244 | 148.40755 |
ASTER 2/1 | 117.26 | 57.04 | 174.3 | 234.0096 | 183.1392 |
ASTER 4/3 | 132.89 | 57.37 | 190.26 | 217.644 | 150.767575 |
S2 11/12 | 128.86 | 58.06 | 186.92 | 240.2932 | 136.57635 |
S2 4/02 | 86.44 | 44.71 | 131.15 | 209.1736 | 158.30321 |
S2 11/8 | 137.46 | 56.01 | 193.47 | 211.134 | 144.257575 |
L8 6/7 | 111.77 | 55.52 | 167.29 | 219.0264 | 115.30955 |
L8 4/2 | 176.06 | 60.80 | 236.86 | 350.7412 | 299.8708 |
L8 6/5 | 136.79 | 60.80 | 197.59 | 216.6624 | 149.785975 |
ALI 8/9 | 118.64 | 51.40 | 170.04 | 205.8885 | 102.17165 |
ALI 4/1 | 172.55 | 43.08 | 215.63 | 234.5877 | 183.717313 |
ALI 8/6 | 169.39 | 53.55 | 222.94 | 240.5781 | 173.701675 |
Intersections | OH | iron oxides | Ferrous oxides | ||
|---|---|---|---|---|---|
ASTER | 252.1244 | 234.0096 | 217.644 | ||
Sentinel 2 | 240.2932 | 136.57635 | 211.134 | ||
L8 | 219.0264 | 115.30955 | 216.6624 | ||
ALI | 205.8885 | 102.17165 | 240.5781 | ||
ASTER + Sentinel 2 | 146.57486 | 101.63106 | 114.72246 | ||
ASTER + L8 | 135.4027 | 87.13305 | 113.3808 | ||
ASTER + ALI | 144.8665 | 73.12402 | 118.516675 | ||
four | 103.71685 | 50.870387 | 66.876425 |
