Skip to main content

Science – Society – Technology

Table 3 Chemical indices calculated for the outcrop and reservoir samples with respect to alteration facies and intensity

From: The impact of hydrothermal alteration on the physiochemical characteristics of reservoir rocks: the case of the Los Humeros geothermal field (Mexico)

Group

CIW

CIA

PIA

CCPI

AI

Outcrop samples:

Teziutlán andesite unit

64.0

59.3

61.0

47.4

33.5

Cuyoaco andesite unit

66.0

61.8

63.5

40.5

26.8

Alteration intensity (reservoir samples):

 Weak

65.2

62.2

63.4

47.3

30.8

 Moderate

67.6

62.2

64.7

42.6

34.9

 Strong

66.3

61.9

63.9

43.4

36.3

Alteration facies (reservoir samples):

 Argillic alteration

66.4

61.9

64.0

43.4

34.0

 Propylitic alteration

66.0

62.7

64.1

49.0

35.6

 Advanced silicification

71.9

64.4

68.6

34.0

42.2

Skarn

60.1

54.5

56.0

24.1

27.4